/*
* Copyright (c) 1998-2022 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
* Copyright (c) 1982, 1986, 1988, 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)uipc_mbuf.c 8.2 (Berkeley) 1/4/94
*/
/*
* NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce
* support for mandatory and extensible security protections. This notice
* is included in support of clause 2.2 (b) of the Apple Public License,
* Version 2.0.
*/
#include <ptrauth.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/syslog.h>
#include <sys/protosw.h>
#include <sys/domain.h>
#include <sys/queue.h>
#include <sys/proc.h>
#include <sys/filedesc.h>
#include <sys/file_internal.h>
#include <vm/vm_kern_xnu.h>
#include <dev/random/randomdev.h>
#include <kern/kern_types.h>
#include <kern/simple_lock.h>
#include <kern/queue.h>
#include <kern/sched_prim.h>
#include <kern/backtrace.h>
#include <kern/percpu.h>
#include <kern/zalloc.h>
#include <libkern/OSDebug.h>
#include <libkern/libkern.h>
#include <os/log.h>
#include <os/ptrtools.h>
#include <IOKit/IOMapper.h>
#include <machine/limits.h>
#include <machine/machine_routines.h>
#include <sys/mcache.h>
#include <net/droptap.h>
#include <netinet/mptcp_var.h>
#include <netinet/tcp_var.h>
#define DUMP_BUF_CHK() { \
clen -= k; \
if (clen < 1) \
goto done; \
c += k; \
}
#if INET
static int
dump_tcp_reass_qlen(char *str, int str_len)
{
char *c = str;
int k, clen = str_len;
if (tcp_reass_total_qlen != 0) {
k = scnprintf(c, clen, "\ntcp reass qlen %d\n", tcp_reass_total_qlen);
DUMP_BUF_CHK();
}
done:
return str_len - clen;
}
#endif /* INET */
#if MPTCP
static int
dump_mptcp_reass_qlen(char *str, int str_len)
{
char *c = str;
int k, clen = str_len;
if (mptcp_reass_total_qlen != 0) {
k = scnprintf(c, clen, "\nmptcp reass qlen %d\n", mptcp_reass_total_qlen);
DUMP_BUF_CHK();
}
done:
return str_len - clen;
}
#endif /* MPTCP */
#if NETWORKING
extern int dlil_dump_top_if_qlen(char *__counted_by(str_len), int str_len);
#endif /* NETWORKING */
/*
* MBUF IMPLEMENTATION NOTES.
*
* There is a total of 5 per-CPU caches:
*
* MC_MBUF:
* This is a cache of rudimentary objects of _MSIZE in size; each
* object represents an mbuf structure. This cache preserves only
* the m_type field of the mbuf during its transactions.
*
* MC_CL:
* This is a cache of rudimentary objects of MCLBYTES in size; each
* object represents a mcluster structure. This cache does not
* preserve the contents of the objects during its transactions.
*
* MC_BIGCL:
* This is a cache of rudimentary objects of MBIGCLBYTES in size; each
* object represents a mbigcluster structure. This cache does not
* preserve the contents of the objects during its transaction.
*
* MC_MBUF_CL:
* This is a cache of mbufs each having a cluster attached to it.
* It is backed by MC_MBUF and MC_CL rudimentary caches. Several
* fields of the mbuf related to the external cluster are preserved
* during transactions.
*
* MC_MBUF_BIGCL:
* This is a cache of mbufs each having a big cluster attached to it.
* It is backed by MC_MBUF and MC_BIGCL rudimentary caches. Several
* fields of the mbuf related to the external cluster are preserved
* during transactions.
*
* OBJECT ALLOCATION:
*
* Allocation requests are handled first at the per-CPU (mcache) layer
* before falling back to the slab layer. Performance is optimal when
* the request is satisfied at the CPU layer because global data/lock
* never gets accessed. When the slab layer is entered for allocation,
* the slab freelist will be checked first for available objects before
* the VM backing store is invoked. Slab layer operations are serialized
* for all of the caches as the mbuf global lock is held most of the time.
* Allocation paths are different depending on the class of objects:
*
* a. Rudimentary object:
*
* { m_get_common(), m_clattach(), m_mclget(),
* m_mclalloc(), m_bigalloc(), m_copym_with_hdrs(),
* composite object allocation }
* | ^
* | |
* | +-----------------------+
* v |
* mcache_alloc/mcache_alloc_ext() mbuf_slab_audit()
* | ^
* v |
* [CPU cache] -------> (found?) -------+
* | |
* v |
* mbuf_slab_alloc() |
* | |
* v |
* +---------> [freelist] -------> (found?) -------+
* | |
* | v
* | m_clalloc()
* | |
* | v
* +---<<---- kmem_mb_alloc()
*
* b. Composite object:
*
* { m_getpackets_internal(), m_allocpacket_internal() }
* | ^
* | |
* | +------ (done) ---------+
* v |
* mcache_alloc/mcache_alloc_ext() mbuf_cslab_audit()
* | ^
* v |
* [CPU cache] -------> (found?) -------+
* | |
* v |
* mbuf_cslab_alloc() |
* | |
* v |
* [freelist] -------> (found?) -------+
* | |
* v |
* (rudimentary object) |
* mcache_alloc/mcache_alloc_ext() ------>>-----+
*
* Auditing notes: If auditing is enabled, buffers will be subjected to
* integrity checks by the audit routine. This is done by verifying their
* contents against DEADBEEF (free) pattern before returning them to caller.
* As part of this step, the routine will also record the transaction and
* pattern-fill the buffers with BADDCAFE (uninitialized) pattern. It will
* also restore any constructed data structure fields if necessary.
*
* OBJECT DEALLOCATION:
*
* Freeing an object simply involves placing it into the CPU cache; this
* pollutes the cache to benefit subsequent allocations. The slab layer
* will only be entered if the object is to be purged out of the cache.
* During normal operations, this happens only when the CPU layer resizes
* its bucket while it's adjusting to the allocation load. Deallocation
* paths are different depending on the class of objects:
*
* a. Rudimentary object:
*
* { m_free(), m_freem_list(), composite object deallocation }
* | ^
* | |
* | +------ (done) ---------+
* v |
* mcache_free/mcache_free_ext() |
* | |
* v |
* mbuf_slab_audit() |
* | |
* v |
* [CPU cache] ---> (not purging?) -----+
* | |
* v |
* mbuf_slab_free() |
* | |
* v |
* [freelist] ----------->>------------+
* (objects get purged to VM only on demand)
*
* b. Composite object:
*
* { m_free(), m_freem_list() }
* | ^
* | |
* | +------ (done) ---------+
* v |
* mcache_free/mcache_free_ext() |
* | |
* v |
* mbuf_cslab_audit() |
* | |
* v |
* [CPU cache] ---> (not purging?) -----+
* | |
* v |
* mbuf_cslab_free() |
* | |
* v |
* [freelist] ---> (not purging?) -----+
* | |
* v |
* (rudimentary object) |
* mcache_free/mcache_free_ext() ------->>------+
*
* Auditing notes: If auditing is enabled, the audit routine will save
* any constructed data structure fields (if necessary) before filling the
* contents of the buffers with DEADBEEF (free) pattern and recording the
* transaction. Buffers that are freed (whether at CPU or slab layer) are
* expected to contain the free pattern.
*
* DEBUGGING:
*
* Debugging can be enabled by adding "mbuf_debug=0x3" to boot-args; this
* translates to the mcache flags (MCF_VERIFY | MCF_AUDIT). Additionally,
* the CPU layer cache can be disabled by setting the MCF_NOCPUCACHE flag,
* i.e. modify the boot argument parameter to "mbuf_debug=0x13". Leak
* detection may also be disabled by setting the MCF_NOLEAKLOG flag, e.g.
* "mbuf_debug=0x113". Note that debugging consumes more CPU and memory.
*
* Each object is associated with exactly one mcache_audit_t structure that
* contains the information related to its last buffer transaction. Given
* an address of an object, the audit structure can be retrieved by finding
* the position of the object relevant to the base address of the cluster:
*
* +------------+ +=============+
* | mbuf addr | | mclaudit[i] |
* +------------+ +=============+
* | | cl_audit[0] |
* i = MTOBG(addr) +-------------+
* | +-----> | cl_audit[1] | -----> mcache_audit_t
* b = BGTOM(i) | +-------------+
* | | | ... |
* x = MCLIDX(b, addr) | +-------------+
* | | | cl_audit[7] |
* +-----------------+ +-------------+
* (e.g. x == 1)
*
* The mclaudit[] array is allocated at initialization time, but its contents
* get populated when the corresponding cluster is created. Because a page
* can be turned into NMBPG number of mbufs, we preserve enough space for the
* mbufs so that there is a 1-to-1 mapping between them. A page that never
* gets (or has not yet) turned into mbufs will use only cl_audit[0] with the
* remaining entries unused. For 16KB cluster, only one entry from the first
* page is allocated and used for the entire object.
*/
extern ppnum_t pmap_find_phys(pmap_t pmap, addr64_t va);
extern vm_map_t mb_map; /* special map */
static uint32_t mb_kmem_contig_failed;
static uint32_t mb_kmem_failed;
static uint32_t mb_kmem_one_failed;
/* Timestamp of allocation failures. */
static uint64_t mb_kmem_contig_failed_ts;
static uint64_t mb_kmem_failed_ts;
static uint64_t mb_kmem_one_failed_ts;
static uint64_t mb_kmem_contig_failed_size;
static uint64_t mb_kmem_failed_size;
static uint32_t mb_kmem_stats[6];
/* Back-end (common) layer */
static uint64_t mb_expand_cnt;
static uint64_t mb_expand_cl_cnt;
static uint64_t mb_expand_cl_total;
static uint64_t mb_expand_bigcl_cnt;
static uint64_t mb_expand_bigcl_total;
static uint64_t mb_expand_16kcl_cnt;
static uint64_t mb_expand_16kcl_total;
static boolean_t mbuf_worker_needs_wakeup; /* wait channel for mbuf worker */
static uint32_t mbuf_worker_run_cnt;
static uint64_t mbuf_worker_last_runtime;
static uint64_t mbuf_drain_last_runtime;
static int mbuf_worker_ready; /* worker thread is runnable */
static unsigned int ncpu; /* number of CPUs */
static ppnum_t *mcl_paddr; /* Array of cluster physical addresses */
static ppnum_t mcl_pages; /* Size of array (# physical pages) */
static ppnum_t mcl_paddr_base; /* Handle returned by IOMapper::iovmAlloc() */
static mcache_t *ref_cache; /* Cache of cluster reference & flags */
static mcache_t *mcl_audit_con_cache; /* Audit contents cache */
unsigned int mbuf_debug; /* patchable mbuf mcache flags */
static unsigned int mb_normalized; /* number of packets "normalized" */
#define MB_GROWTH_AGGRESSIVE 1 /* Threshold: 1/2 of total */
#define MB_GROWTH_NORMAL 2 /* Threshold: 3/4 of total */
#define MBUF_CLASS_VALID(c) \
((int)(c) >= MBUF_CLASS_MIN && (int)(c) <= MBUF_CLASS_MAX)
/*
* mbuf specific mcache allocation request flags.
*/
#define MCR_COMP MCR_USR1 /* for MC_MBUF_{CL,BIGCL,16KCL} caches */
/*
* Per-cluster slab structure.
*
* A slab is a cluster control structure that contains one or more object
* chunks; the available chunks are chained in the slab's freelist (sl_head).
* Each time a chunk is taken out of the slab, the slab's reference count
* gets incremented. When all chunks have been taken out, the empty slab
* gets removed (SLF_DETACHED) from the class's slab list. A chunk that is
* returned to a slab causes the slab's reference count to be decremented;
* it also causes the slab to be reinserted back to class's slab list, if
* it's not already done.
*
* Compartmentalizing of the object chunks into slabs allows us to easily
* merge one or more slabs together when the adjacent slabs are idle, as
* well as to convert or move a slab from one class to another; e.g. the
* mbuf cluster slab can be converted to a regular cluster slab when all
* mbufs in the slab have been freed.
*
* A slab may also span across multiple clusters for chunks larger than
* a cluster's size. In this case, only the slab of the first cluster is
* used. The rest of the slabs are marked with SLF_PARTIAL to indicate
* that they are part of the larger slab.
*
* Each slab controls a page of memory.
*/
typedef struct mcl_slab {
struct mcl_slab *sl_next; /* neighboring slab */
u_int8_t sl_class; /* controlling mbuf class */
int8_t sl_refcnt; /* outstanding allocations */
int8_t sl_chunks; /* chunks (bufs) in this slab */
u_int16_t sl_flags; /* slab flags (see below) */
u_int16_t sl_len; /* slab length */
void *sl_base; /* base of allocated memory */
void *sl_head; /* first free buffer */
TAILQ_ENTRY(mcl_slab) sl_link; /* next/prev slab on freelist */
} mcl_slab_t;
#define SLF_MAPPED 0x0001 /* backed by a mapped page */
#define SLF_PARTIAL 0x0002 /* part of another slab */
#define SLF_DETACHED 0x0004 /* not in slab freelist */
/*
* The array of slabs are broken into groups of arrays per 1MB of kernel
* memory to reduce the footprint. Each group is allocated on demand
* whenever a new piece of memory mapped in from the VM crosses the 1MB
* boundary.
*/
#define NSLABSPMB ((1 << MBSHIFT) >> PAGE_SHIFT)
typedef struct mcl_slabg {
mcl_slab_t *slg_slab; /* group of slabs */
} mcl_slabg_t;
/*
* Number of slabs needed to control a 16KB cluster object.
*/
#define NSLABSP16KB (M16KCLBYTES >> PAGE_SHIFT)
/*
* Per-cluster audit structure.
*/
typedef struct {
mcache_audit_t **cl_audit; /* array of audits */
} mcl_audit_t;
typedef struct {
struct thread *msa_thread; /* thread doing transaction */
struct thread *msa_pthread; /* previous transaction thread */
uint32_t msa_tstamp; /* transaction timestamp (ms) */
uint32_t msa_ptstamp; /* prev transaction timestamp (ms) */
uint16_t msa_depth; /* pc stack depth */
uint16_t msa_pdepth; /* previous transaction pc stack */
void *msa_stack[MCACHE_STACK_DEPTH];
void *msa_pstack[MCACHE_STACK_DEPTH];
} mcl_scratch_audit_t;
typedef struct {
/*
* Size of data from the beginning of an mbuf that covers m_hdr,
* pkthdr and m_ext structures. If auditing is enabled, we allocate
* a shadow mbuf structure of this size inside each audit structure,
* and the contents of the real mbuf gets copied into it when the mbuf
* is freed. This allows us to pattern-fill the mbuf for integrity
* check, and to preserve any constructed mbuf fields (e.g. mbuf +
* cluster cache case). Note that we don't save the contents of
* clusters when they are freed; we simply pattern-fill them.
*/
u_int8_t sc_mbuf[(_MSIZE - _MHLEN) + sizeof(_m_ext_t)];
mcl_scratch_audit_t sc_scratch __attribute__((aligned(8)));
} mcl_saved_contents_t;
#define AUDIT_CONTENTS_SIZE (sizeof (mcl_saved_contents_t))
#define MCA_SAVED_MBUF_PTR(_mca) \
((struct mbuf *)(void *)((mcl_saved_contents_t *) \
(_mca)->mca_contents)->sc_mbuf)
#define MCA_SAVED_MBUF_SIZE \
(sizeof (((mcl_saved_contents_t *)0)->sc_mbuf))
#define MCA_SAVED_SCRATCH_PTR(_mca) \
(&((mcl_saved_contents_t *)(_mca)->mca_contents)->sc_scratch)
/*
* mbuf specific mcache audit flags
*/
#define MB_INUSE 0x01 /* object has not been returned to slab */
#define MB_COMP_INUSE 0x02 /* object has not been returned to cslab */
#define MB_SCVALID 0x04 /* object has valid saved contents */
/*
* Each of the following two arrays hold up to nmbclusters elements.
*/
static mcl_audit_t *mclaudit; /* array of cluster audit information */
static unsigned int maxclaudit; /* max # of entries in audit table */
static mcl_slabg_t **slabstbl; /* cluster slabs table */
static unsigned int maxslabgrp; /* max # of entries in slabs table */
static unsigned int slabgrp; /* # of entries in slabs table */
/* Globals */
unsigned char *mbutl; /* first mapped cluster address */
static unsigned char *embutl; /* ending virtual address of mclusters */
static boolean_t mclverify; /* debug: pattern-checking */
static boolean_t mcltrace; /* debug: stack tracing */
static boolean_t mclfindleak; /* debug: leak detection */
static boolean_t mclexpleak; /* debug: expose leak info to user space */
static struct timeval mb_start; /* beginning of time */
/* mbuf leak detection variables */
static struct mleak_table mleak_table;
static mleak_stat_t *mleak_stat;
#define MLEAK_STAT_SIZE(n) \
__builtin_offsetof(mleak_stat_t, ml_trace[n])
struct mallocation {
mcache_obj_t *element; /* the alloc'ed element, NULL if unused */
u_int32_t trace_index; /* mtrace index for corresponding backtrace */
u_int32_t count; /* How many objects were requested */
u_int64_t hitcount; /* for determining hash effectiveness */
};
struct mtrace {
u_int64_t collisions;
u_int64_t hitcount;
u_int64_t allocs;
u_int64_t depth;
uintptr_t addr[MLEAK_STACK_DEPTH];
};
/* Size must be a power of two for the zhash to be able to just mask off bits */
#define MLEAK_ALLOCATION_MAP_NUM 512
#define MLEAK_TRACE_MAP_NUM 256
/*
* Sample factor for how often to record a trace. This is overwritable
* by the boot-arg mleak_sample_factor.
*/
#define MLEAK_SAMPLE_FACTOR 500
/*
* Number of top leakers recorded.
*/
#define MLEAK_NUM_TRACES 5
#define MB_LEAK_SPACING_64 " "
#define MB_LEAK_SPACING_32 " "
#define MB_LEAK_HDR_32 "\n\
trace [1] trace [2] trace [3] trace [4] trace [5] \n\
---------- ---------- ---------- ---------- ---------- \n\
"
#define MB_LEAK_HDR_64 "\n\
trace [1] trace [2] trace [3] \
trace [4] trace [5] \n\
------------------ ------------------ ------------------ \
------------------ ------------------ \n\
"
static uint32_t mleak_alloc_buckets = MLEAK_ALLOCATION_MAP_NUM;
static uint32_t mleak_trace_buckets = MLEAK_TRACE_MAP_NUM;
/* Hashmaps of allocations and their corresponding traces */
static struct mallocation *mleak_allocations;
static struct mtrace *mleak_traces;
static struct mtrace *mleak_top_trace[MLEAK_NUM_TRACES];
/* Lock to protect mleak tables from concurrent modification */
static LCK_GRP_DECLARE(mleak_lock_grp, "mleak_lock");
static LCK_MTX_DECLARE(mleak_lock_data, &mleak_lock_grp);
static lck_mtx_t *const mleak_lock = &mleak_lock_data;
/* *Failed* large allocations. */
struct mtracelarge {
uint64_t size;
uint64_t depth;
uintptr_t addr[MLEAK_STACK_DEPTH];
};
#define MTRACELARGE_NUM_TRACES 5
static struct mtracelarge mtracelarge_table[MTRACELARGE_NUM_TRACES];
static void mtracelarge_register(size_t size);
/* The minimum number of objects that are allocated, to start. */
#define MINCL 32
#define MINBIGCL (MINCL >> 1)
/* Low watermarks (only map in pages once free counts go below) */
#define MBIGCL_LOWAT MINBIGCL
#define m_cache(c) mbuf_table[c].mtbl_cache
#define m_slablist(c) mbuf_table[c].mtbl_slablist
#define m_cobjlist(c) mbuf_table[c].mtbl_cobjlist
#define m_wantpurge(c) mbuf_table[c].mtbl_wantpurge
#define m_active(c) mbuf_table[c].mtbl_stats->mbcl_active
#define m_slab_cnt(c) mbuf_table[c].mtbl_stats->mbcl_slab_cnt
#define m_alloc_cnt(c) mbuf_table[c].mtbl_stats->mbcl_alloc_cnt
#define m_free_cnt(c) mbuf_table[c].mtbl_stats->mbcl_free_cnt
#define m_notified(c) mbuf_table[c].mtbl_stats->mbcl_notified
#define m_purge_cnt(c) mbuf_table[c].mtbl_stats->mbcl_purge_cnt
#define m_fail_cnt(c) mbuf_table[c].mtbl_stats->mbcl_fail_cnt
#define m_release_cnt(c) mbuf_table[c].mtbl_stats->mbcl_release_cnt
#define m_region_expand(c) mbuf_table[c].mtbl_expand
mbuf_table_t mbuf_table[] = {
/*
* The caches for mbufs, regular clusters and big clusters.
* The average total values were based on data gathered by actual
* usage patterns on iOS.
*/
{ MC_MBUF, NULL, TAILQ_HEAD_INITIALIZER(m_slablist(MC_MBUF)),
NULL, NULL, 0, 0, 0, 0, 3000, 0 },
{ MC_CL, NULL, TAILQ_HEAD_INITIALIZER(m_slablist(MC_CL)),
NULL, NULL, 0, 0, 0, 0, 2000, 0 },
{ MC_BIGCL, NULL, TAILQ_HEAD_INITIALIZER(m_slablist(MC_BIGCL)),
NULL, NULL, 0, 0, 0, 0, 1000, 0 },
{ MC_16KCL, NULL, TAILQ_HEAD_INITIALIZER(m_slablist(MC_16KCL)),
NULL, NULL, 0, 0, 0, 0, 200, 0 },
/*
* The following are special caches; they serve as intermediate
* caches backed by the above rudimentary caches. Each object
* in the cache is an mbuf with a cluster attached to it. Unlike
* the above caches, these intermediate caches do not directly
* deal with the slab structures; instead, the constructed
* cached elements are simply stored in the freelists.
*/
{ MC_MBUF_CL, NULL, { NULL, NULL }, NULL, NULL, 0, 0, 0, 0, 2000, 0 },
{ MC_MBUF_BIGCL, NULL, { NULL, NULL }, NULL, NULL, 0, 0, 0, 0, 1000, 0 },
{ MC_MBUF_16KCL, NULL, { NULL, NULL }, NULL, NULL, 0, 0, 0, 0, 200, 0 },
};
#if SKYWALK
#define MC_THRESHOLD_SCALE_DOWN_FACTOR 2
static unsigned int mc_threshold_scale_down_factor =
MC_THRESHOLD_SCALE_DOWN_FACTOR;
#endif /* SKYWALK */
static uint32_t
m_avgtotal(mbuf_class_t c)
{
#if SKYWALK
return if_is_fsw_transport_netagent_enabled() ?
(mbuf_table[c].mtbl_avgtotal / mc_threshold_scale_down_factor) :
mbuf_table[c].mtbl_avgtotal;
#else /* !SKYWALK */
return mbuf_table[c].mtbl_avgtotal;
#endif /* SKYWALK */
}
static void *mb_waitchan = &mbuf_table; /* wait channel for all caches */
static int mb_waiters; /* number of waiters */
static struct timeval mb_wdtstart; /* watchdog start timestamp */
static char *mbuf_dump_buf;
#define MBUF_DUMP_BUF_SIZE 4096
/*
* mbuf watchdog is enabled by default. It is also toggeable via the
* kern.ipc.mb_watchdog sysctl.
* Garbage collection is enabled by default on embedded platforms.
* mb_drain_maxint controls the amount of time to wait (in seconds) before
* consecutive calls to mbuf_drain().
*/
static unsigned int mb_watchdog = 1;
#if !XNU_TARGET_OS_OSX
static unsigned int mb_drain_maxint = 60;
#else /* XNU_TARGET_OS_OSX */
static unsigned int mb_drain_maxint = 0;
#endif /* XNU_TARGET_OS_OSX */
/* The following are used to serialize m_clalloc() */
static boolean_t mb_clalloc_busy;
static void *mb_clalloc_waitchan = &mb_clalloc_busy;
static int mb_clalloc_waiters;
static char *mbuf_dump(void);
static void mbuf_worker_thread_init(void);
static mcache_obj_t *slab_alloc(mbuf_class_t, int);
static void slab_free(mbuf_class_t, mcache_obj_t *);
static unsigned int mbuf_slab_alloc(void *, mcache_obj_t ***,
unsigned int, int);
static void mbuf_slab_free(void *, mcache_obj_t *, int);
static void mbuf_slab_audit(void *, mcache_obj_t *, boolean_t);
static void mbuf_slab_notify(void *, u_int32_t);
static unsigned int cslab_alloc(mbuf_class_t, mcache_obj_t ***,
unsigned int);
static unsigned int cslab_free(mbuf_class_t, mcache_obj_t *, int);
static unsigned int mbuf_cslab_alloc(void *, mcache_obj_t ***,
unsigned int, int);
static void mbuf_cslab_free(void *, mcache_obj_t *, int);
static void mbuf_cslab_audit(void *, mcache_obj_t *, boolean_t);
static int freelist_populate(mbuf_class_t, unsigned int, int);
static void freelist_init(mbuf_class_t);
static boolean_t mbuf_cached_above(mbuf_class_t, int);
static boolean_t mbuf_steal(mbuf_class_t, unsigned int);
static void m_reclaim(mbuf_class_t, unsigned int, boolean_t);
static int m_howmany(int, size_t);
static void mbuf_worker_thread(void);
static void mbuf_watchdog(void);
static boolean_t mbuf_sleep(mbuf_class_t, unsigned int, int);
static void mcl_audit_init(void *, mcache_audit_t **, mcache_obj_t **,
size_t, unsigned int);
static void mcl_audit_free(void *, unsigned int);
static mcache_audit_t *mcl_audit_buf2mca(mbuf_class_t, mcache_obj_t *);
static void mcl_audit_mbuf(mcache_audit_t *, void *, boolean_t, boolean_t);
static void mcl_audit_cluster(mcache_audit_t *, void *, size_t, boolean_t,
boolean_t);
static void mcl_audit_restore_mbuf(struct mbuf *, mcache_audit_t *, boolean_t);
static void mcl_audit_save_mbuf(struct mbuf *, mcache_audit_t *);
static void mcl_audit_scratch(mcache_audit_t *);
static void mcl_audit_mcheck_panic(struct mbuf *);
static void mcl_audit_verify_nextptr(void *, mcache_audit_t *);
static void mleak_activate(void);
static void mleak_logger(u_int32_t, mcache_obj_t *, boolean_t);
static boolean_t mleak_log(uintptr_t *, mcache_obj_t *, uint32_t, int);
static void mleak_free(mcache_obj_t *);
static void mleak_sort_traces(void);
static void mleak_update_stats(void);
static mcl_slab_t *slab_get(void *);
static void slab_init(mcl_slab_t *, mbuf_class_t, u_int32_t,
void *, void *, unsigned int, int, int);
static void slab_insert(mcl_slab_t *, mbuf_class_t);
static void slab_remove(mcl_slab_t *, mbuf_class_t);
static boolean_t slab_inrange(mcl_slab_t *, void *);
static void slab_nextptr_panic(mcl_slab_t *, void *);
static void slab_detach(mcl_slab_t *);
static boolean_t slab_is_detached(mcl_slab_t *);
#if (DEBUG || DEVELOPMENT)
#define mbwdog_logger(fmt, ...) _mbwdog_logger(__func__, __LINE__, fmt, ## __VA_ARGS__)
static void _mbwdog_logger(const char *func, const int line, const char *fmt, ...);
static char *mbwdog_logging;
const unsigned mbwdog_logging_size = 4096;
static size_t mbwdog_logging_used;
#else
#define mbwdog_logger(fmt, ...) do { } while (0)
#endif /* DEBUG || DEVELOPMENT */
static void mbuf_drain_locked(boolean_t);
void
mbuf_mcheck(struct mbuf *m)
{
if (__improbable(m->m_type != MT_FREE && !MBUF_IS_PAIRED(m))) {
if (mclaudit == NULL) {
panic("MCHECK: m_type=%d m=%p",
(u_int16_t)(m)->m_type, m);
} else {
mcl_audit_mcheck_panic(m);
}
}
}
#define MBUF_IN_MAP(addr) \
((unsigned char *)(addr) >= mbutl && \
(unsigned char *)(addr) < embutl)
#define MRANGE(addr) { \
if (!MBUF_IN_MAP(addr)) \
panic("MRANGE: address out of range 0x%p", addr); \
}
/*
* Macros to obtain page index given a base cluster address
*/
#define MTOPG(x) (((unsigned char *)x - mbutl) >> PAGE_SHIFT)
#define PGTOM(x) (mbutl + (x << PAGE_SHIFT))
/*
* Macro to find the mbuf index relative to a base.
*/
#define MBPAGEIDX(c, m) \
(((unsigned char *)(m) - (unsigned char *)(c)) >> _MSIZESHIFT)
/*
* Same thing for 2KB cluster index.
*/
#define CLPAGEIDX(c, m) \
(((unsigned char *)(m) - (unsigned char *)(c)) >> MCLSHIFT)
/*
* Macro to find 4KB cluster index relative to a base
*/
#define BCLPAGEIDX(c, m) \
(((unsigned char *)(m) - (unsigned char *)(c)) >> MBIGCLSHIFT)
/*
* Macro to convert BSD malloc sleep flag to mcache's
*/
#define MSLEEPF(f) ((!((f) & M_DONTWAIT)) ? MCR_SLEEP : MCR_NOSLEEP)
static int
mleak_top_trace_sysctl SYSCTL_HANDLER_ARGS
{
#pragma unused(oidp, arg1, arg2)
int i;
/* Ensure leak tracing turned on */
if (!mclfindleak || !mclexpleak) {
return ENXIO;
}
lck_mtx_lock(mleak_lock);
mleak_update_stats();
i = SYSCTL_OUT(req, mleak_stat, MLEAK_STAT_SIZE(MLEAK_NUM_TRACES));
lck_mtx_unlock(mleak_lock);
return i;
}
static int
mleak_table_sysctl SYSCTL_HANDLER_ARGS
{
#pragma unused(oidp, arg1, arg2)
int i = 0;
/* Ensure leak tracing turned on */
if (!mclfindleak || !mclexpleak) {
return ENXIO;
}
lck_mtx_lock(mleak_lock);
i = SYSCTL_OUT(req, &mleak_table, sizeof(mleak_table));
lck_mtx_unlock(mleak_lock);
return i;
}
void
mbuf_stat_sync(void)
{
mb_class_stat_t *sp;
mcache_cpu_t *ccp;
mcache_t *cp;
int k, m, bktsize;
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
for (k = 0; k < MC_MAX; k++) {
cp = m_cache(k);
ccp = &cp->mc_cpu[0];
bktsize = ccp->cc_bktsize;
sp = mbuf_table[k].mtbl_stats;
if (cp->mc_flags & MCF_NOCPUCACHE) {
sp->mbcl_mc_state = MCS_DISABLED;
} else if (cp->mc_purge_cnt > 0) {
sp->mbcl_mc_state = MCS_PURGING;
} else if (bktsize == 0) {
sp->mbcl_mc_state = MCS_OFFLINE;
} else {
sp->mbcl_mc_state = MCS_ONLINE;
}
sp->mbcl_mc_cached = 0;
for (m = 0; m < ncpu; m++) {
ccp = &cp->mc_cpu[m];
if (ccp->cc_objs > 0) {
sp->mbcl_mc_cached += ccp->cc_objs;
}
if (ccp->cc_pobjs > 0) {
sp->mbcl_mc_cached += ccp->cc_pobjs;
}
}
sp->mbcl_mc_cached += (cp->mc_full.bl_total * bktsize);
sp->mbcl_active = sp->mbcl_total - sp->mbcl_mc_cached -
sp->mbcl_infree;
sp->mbcl_mc_waiter_cnt = cp->mc_waiter_cnt;
sp->mbcl_mc_wretry_cnt = cp->mc_wretry_cnt;
sp->mbcl_mc_nwretry_cnt = cp->mc_nwretry_cnt;
/* Calculate total count specific to each class */
sp->mbcl_ctotal = sp->mbcl_total;
switch (m_class(k)) {
case MC_MBUF:
/* Deduct mbufs used in composite caches */
sp->mbcl_ctotal -= (m_total(MC_MBUF_CL) +
m_total(MC_MBUF_BIGCL) - m_total(MC_MBUF_16KCL));
break;
case MC_CL:
/* Deduct clusters used in composite cache */
sp->mbcl_ctotal -= m_total(MC_MBUF_CL);
break;
case MC_BIGCL:
/* Deduct clusters used in composite cache */
sp->mbcl_ctotal -= m_total(MC_MBUF_BIGCL);
break;
case MC_16KCL:
/* Deduct clusters used in composite cache */
sp->mbcl_ctotal -= m_total(MC_MBUF_16KCL);
break;
default:
break;
}
}
}
bool
mbuf_class_under_pressure(struct mbuf *m)
{
int mclass = mbuf_get_class(m);
if (m_total(mclass) - m_infree(mclass) >= (m_maxlimit(mclass) * mb_memory_pressure_percentage) / 100) {
/*
* The above computation does not include the per-CPU cached objects.
* As a fast-path check this is good-enough. But now we do
* the "slower" count of the cached objects to know exactly the
* number of active mbufs in use.
*
* We do not take the mbuf_lock here to avoid lock-contention. Numbers
* might be slightly off but we don't try to be 100% accurate.
* At worst, we drop a packet that we shouldn't have dropped or
* we might go slightly above our memory-pressure threshold.
*/
mcache_t *cp = m_cache(mclass);
mcache_cpu_t *ccp = &cp->mc_cpu[0];
int bktsize = os_access_once(ccp->cc_bktsize);
uint32_t bl_total = os_access_once(cp->mc_full.bl_total);
uint32_t cached = 0;
int i;
for (i = 0; i < ncpu; i++) {
ccp = &cp->mc_cpu[i];
int cc_objs = os_access_once(ccp->cc_objs);
if (cc_objs > 0) {
cached += cc_objs;
}
int cc_pobjs = os_access_once(ccp->cc_pobjs);
if (cc_pobjs > 0) {
cached += cc_pobjs;
}
}
cached += (bl_total * bktsize);
if (m_total(mclass) - m_infree(mclass) - cached >= (m_maxlimit(mclass) * mb_memory_pressure_percentage) / 100) {
os_log(OS_LOG_DEFAULT,
"%s memory-pressure on mbuf due to class %u, total %u free %u cached %u max %u",
__func__, mclass, m_total(mclass), m_infree(mclass), cached, m_maxlimit(mclass));
return true;
}
}
return false;
}
__private_extern__ void
mbinit(void)
{
unsigned int m;
unsigned int initmcl = 0;
thread_t thread = THREAD_NULL;
microuptime(&mb_start);
/*
* These MBUF_ values must be equal to their private counterparts.
*/
static_assert(MBUF_EXT == M_EXT);
static_assert(MBUF_PKTHDR == M_PKTHDR);
static_assert(MBUF_EOR == M_EOR);
static_assert(MBUF_LOOP == M_LOOP);
static_assert(MBUF_BCAST == M_BCAST);
static_assert(MBUF_MCAST == M_MCAST);
static_assert(MBUF_FRAG == M_FRAG);
static_assert(MBUF_FIRSTFRAG == M_FIRSTFRAG);
static_assert(MBUF_LASTFRAG == M_LASTFRAG);
static_assert(MBUF_PROMISC == M_PROMISC);
static_assert(MBUF_HASFCS == M_HASFCS);
static_assert(MBUF_TYPE_FREE == MT_FREE);
static_assert(MBUF_TYPE_DATA == MT_DATA);
static_assert(MBUF_TYPE_HEADER == MT_HEADER);
static_assert(MBUF_TYPE_SOCKET == MT_SOCKET);
static_assert(MBUF_TYPE_PCB == MT_PCB);
static_assert(MBUF_TYPE_RTABLE == MT_RTABLE);
static_assert(MBUF_TYPE_HTABLE == MT_HTABLE);
static_assert(MBUF_TYPE_ATABLE == MT_ATABLE);
static_assert(MBUF_TYPE_SONAME == MT_SONAME);
static_assert(MBUF_TYPE_SOOPTS == MT_SOOPTS);
static_assert(MBUF_TYPE_FTABLE == MT_FTABLE);
static_assert(MBUF_TYPE_RIGHTS == MT_RIGHTS);
static_assert(MBUF_TYPE_IFADDR == MT_IFADDR);
static_assert(MBUF_TYPE_CONTROL == MT_CONTROL);
static_assert(MBUF_TYPE_OOBDATA == MT_OOBDATA);
static_assert(MBUF_TSO_IPV4 == CSUM_TSO_IPV4);
static_assert(MBUF_TSO_IPV6 == CSUM_TSO_IPV6);
static_assert(MBUF_CSUM_REQ_SUM16 == CSUM_PARTIAL);
static_assert(MBUF_CSUM_TCP_SUM16 == MBUF_CSUM_REQ_SUM16);
static_assert(MBUF_CSUM_REQ_ZERO_INVERT == CSUM_ZERO_INVERT);
static_assert(MBUF_CSUM_REQ_IP == CSUM_IP);
static_assert(MBUF_CSUM_REQ_TCP == CSUM_TCP);
static_assert(MBUF_CSUM_REQ_UDP == CSUM_UDP);
static_assert(MBUF_CSUM_REQ_TCPIPV6 == CSUM_TCPIPV6);
static_assert(MBUF_CSUM_REQ_UDPIPV6 == CSUM_UDPIPV6);
static_assert(MBUF_CSUM_DID_IP == CSUM_IP_CHECKED);
static_assert(MBUF_CSUM_IP_GOOD == CSUM_IP_VALID);
static_assert(MBUF_CSUM_DID_DATA == CSUM_DATA_VALID);
static_assert(MBUF_CSUM_PSEUDO_HDR == CSUM_PSEUDO_HDR);
static_assert(MBUF_WAITOK == M_WAIT);
static_assert(MBUF_DONTWAIT == M_DONTWAIT);
static_assert(MBUF_COPYALL == M_COPYALL);
static_assert(MBUF_SC2TC(MBUF_SC_BK_SYS) == MBUF_TC_BK);
static_assert(MBUF_SC2TC(MBUF_SC_BK) == MBUF_TC_BK);
static_assert(MBUF_SC2TC(MBUF_SC_BE) == MBUF_TC_BE);
static_assert(MBUF_SC2TC(MBUF_SC_RD) == MBUF_TC_BE);
static_assert(MBUF_SC2TC(MBUF_SC_OAM) == MBUF_TC_BE);
static_assert(MBUF_SC2TC(MBUF_SC_AV) == MBUF_TC_VI);
static_assert(MBUF_SC2TC(MBUF_SC_RV) == MBUF_TC_VI);
static_assert(MBUF_SC2TC(MBUF_SC_VI) == MBUF_TC_VI);
static_assert(MBUF_SC2TC(MBUF_SC_SIG) == MBUF_TC_VI);
static_assert(MBUF_SC2TC(MBUF_SC_VO) == MBUF_TC_VO);
static_assert(MBUF_SC2TC(MBUF_SC_CTL) == MBUF_TC_VO);
static_assert(MBUF_TC2SCVAL(MBUF_TC_BK) == SCVAL_BK);
static_assert(MBUF_TC2SCVAL(MBUF_TC_BE) == SCVAL_BE);
static_assert(MBUF_TC2SCVAL(MBUF_TC_VI) == SCVAL_VI);
static_assert(MBUF_TC2SCVAL(MBUF_TC_VO) == SCVAL_VO);
/* Module specific scratch space (32-bit alignment requirement) */
static_assert(!(offsetof(struct mbuf, m_pkthdr.pkt_mpriv) % sizeof(uint32_t)));
/* Make sure we don't save more than we should */
static_assert(MCA_SAVED_MBUF_SIZE <= sizeof(struct mbuf));
if (nmbclusters == 0) {
nmbclusters = NMBCLUSTERS;
}
/* This should be a sane (at least even) value by now */
VERIFY(nmbclusters != 0 && !(nmbclusters & 0x1));
/* Setup the mbuf table */
mbuf_table_init();
static_assert(sizeof(struct mbuf) == _MSIZE);
/*
* Allocate cluster slabs table:
*
* maxslabgrp = (N * 2048) / (1024 * 1024)
*
* Where N is nmbclusters rounded up to the nearest 512. This yields
* mcl_slab_g_t units, each one representing a MB of memory.
*/
maxslabgrp =
(P2ROUNDUP(nmbclusters, (MBSIZE >> MCLSHIFT)) << MCLSHIFT) >> MBSHIFT;
slabstbl = zalloc_permanent(maxslabgrp * sizeof(mcl_slabg_t *),
ZALIGN(mcl_slabg_t));
/*
* Allocate audit structures, if needed:
*
* maxclaudit = (maxslabgrp * 1024 * 1024) / PAGE_SIZE
*
* This yields mcl_audit_t units, each one representing a page.
*/
PE_parse_boot_argn("mbuf_debug", &mbuf_debug, sizeof(mbuf_debug));
mbuf_debug |= mcache_getflags();
if (mbuf_debug & MCF_DEBUG) {
int l;
mcl_audit_t *mclad;
maxclaudit = ((maxslabgrp << MBSHIFT) >> PAGE_SHIFT);
mclaudit = zalloc_permanent(maxclaudit * sizeof(*mclaudit),
ZALIGN(mcl_audit_t));
for (l = 0, mclad = mclaudit; l < maxclaudit; l++) {
mclad[l].cl_audit = zalloc_permanent(NMBPG * sizeof(mcache_audit_t *),
ZALIGN_PTR);
}
mcl_audit_con_cache = mcache_create("mcl_audit_contents",
AUDIT_CONTENTS_SIZE, sizeof(u_int64_t), 0, MCR_SLEEP);
VERIFY(mcl_audit_con_cache != NULL);
}
mclverify = (mbuf_debug & MCF_VERIFY);
mcltrace = (mbuf_debug & MCF_TRACE);
mclfindleak = !(mbuf_debug & MCF_NOLEAKLOG);
mclexpleak = mclfindleak && (mbuf_debug & MCF_EXPLEAKLOG);
/* Enable mbuf leak logging, with a lock to protect the tables */
mleak_activate();
/*
* Allocate structure for per-CPU statistics that's aligned
* on the CPU cache boundary; this code assumes that we never
* uninitialize this framework, since the original address
* before alignment is not saved.
*/
ncpu = ml_wait_max_cpus();
/* Calculate the number of pages assigned to the cluster pool */
mcl_pages = (nmbclusters << MCLSHIFT) / PAGE_SIZE;
mcl_paddr = zalloc_permanent(mcl_pages * sizeof(ppnum_t),
ZALIGN(ppnum_t));
/* Register with the I/O Bus mapper */
mcl_paddr_base = IOMapperIOVMAlloc(mcl_pages);
embutl = (mbutl + (nmbclusters * MCLBYTES));
VERIFY(((embutl - mbutl) % MBIGCLBYTES) == 0);
/* Prime up the freelist */
PE_parse_boot_argn("initmcl", &initmcl, sizeof(initmcl));
if (initmcl != 0) {
initmcl >>= NCLPBGSHIFT; /* become a 4K unit */
if (initmcl > m_maxlimit(MC_BIGCL)) {
initmcl = m_maxlimit(MC_BIGCL);
}
}
if (initmcl < m_minlimit(MC_BIGCL)) {
initmcl = m_minlimit(MC_BIGCL);
}
lck_mtx_lock(mbuf_mlock);
/*
* For classes with non-zero minimum limits, populate their freelists
* so that m_total(class) is at least m_minlimit(class).
*/
VERIFY(m_total(MC_BIGCL) == 0 && m_minlimit(MC_BIGCL) != 0);
freelist_populate(m_class(MC_BIGCL), initmcl, M_WAIT);
VERIFY(m_total(MC_BIGCL) >= m_minlimit(MC_BIGCL));
freelist_init(m_class(MC_CL));
for (m = 0; m < MC_MAX; m++) {
/* Make sure we didn't miss any */
VERIFY(m_minlimit(m_class(m)) == 0 ||
m_total(m_class(m)) >= m_minlimit(m_class(m)));
}
lck_mtx_unlock(mbuf_mlock);
(void) kernel_thread_start((thread_continue_t)mbuf_worker_thread_init,
NULL, &thread);
thread_deallocate(thread);
ref_cache = mcache_create("mext_ref", sizeof(struct ext_ref),
0, 0, MCR_SLEEP);
/* Create the cache for each class */
for (m = 0; m < MC_MAX; m++) {
void *allocfunc, *freefunc, *auditfunc, *logfunc;
u_int32_t flags;
flags = mbuf_debug;
if (m_class(m) == MC_MBUF_CL || m_class(m) == MC_MBUF_BIGCL ||
m_class(m) == MC_MBUF_16KCL) {
allocfunc = mbuf_cslab_alloc;
freefunc = mbuf_cslab_free;
auditfunc = mbuf_cslab_audit;
logfunc = mleak_logger;
} else {
allocfunc = mbuf_slab_alloc;
freefunc = mbuf_slab_free;
auditfunc = mbuf_slab_audit;
logfunc = mleak_logger;
}
if (!mclfindleak) {
flags |= MCF_NOLEAKLOG;
}
m_cache(m) = mcache_create_ext(m_cname(m), m_maxsize(m),
allocfunc, freefunc, auditfunc, logfunc, mbuf_slab_notify,
(void *)(uintptr_t)m, flags, MCR_SLEEP);
}
/*
* Set the max limit on sb_max to be 1/16 th of the size of
* memory allocated for mbuf clusters.
*/
high_sb_max = (nmbclusters << (MCLSHIFT - 4));
if (high_sb_max < sb_max) {
/* sb_max is too large for this configuration, scale it down */
if (high_sb_max > (1 << MBSHIFT)) {
/* We have atleast 16 M of mbuf pool */
sb_max = high_sb_max;
} else if ((nmbclusters << MCLSHIFT) > (1 << MBSHIFT)) {
/*
* If we have more than 1M of mbufpool, cap the size of
* max sock buf at 1M
*/
sb_max = high_sb_max = (1 << MBSHIFT);
} else {
sb_max = high_sb_max;
}
}
/* allocate space for mbuf_dump_buf */
mbuf_dump_buf = zalloc_permanent(MBUF_DUMP_BUF_SIZE, ZALIGN_NONE);
if (mbuf_debug & MCF_DEBUG) {
printf("%s: MLEN %d, MHLEN %d\n", __func__,
(int)_MLEN, (int)_MHLEN);
}
printf("%s: done [%d MB total pool size, (%d/%d) split]\n", __func__,
(nmbclusters << MCLSHIFT) >> MBSHIFT,
(nclusters << MCLSHIFT) >> MBSHIFT,
(njcl << MCLSHIFT) >> MBSHIFT);
}
/*
* Obtain a slab of object(s) from the class's freelist.
*/
static mcache_obj_t *
slab_alloc(mbuf_class_t class, int wait)
{
mcl_slab_t *sp;
mcache_obj_t *buf;
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
/* This should always be NULL for us */
VERIFY(m_cobjlist(class) == NULL);
/*
* Treat composite objects as having longer lifespan by using
* a slab from the reverse direction, in hoping that this could
* reduce the probability of fragmentation for slabs that hold
* more than one buffer chunks (e.g. mbuf slabs). For other
* slabs, this probably doesn't make much of a difference.
*/
if ((class == MC_MBUF || class == MC_CL || class == MC_BIGCL)
&& (wait & MCR_COMP)) {
sp = (mcl_slab_t *)TAILQ_LAST(&m_slablist(class), mcl_slhead);
} else {
sp = (mcl_slab_t *)TAILQ_FIRST(&m_slablist(class));
}
if (sp == NULL) {
VERIFY(m_infree(class) == 0 && m_slab_cnt(class) == 0);
/* The slab list for this class is empty */
return NULL;
}
VERIFY(m_infree(class) > 0);
VERIFY(!slab_is_detached(sp));
VERIFY(sp->sl_class == class &&
(sp->sl_flags & (SLF_MAPPED | SLF_PARTIAL)) == SLF_MAPPED);
buf = sp->sl_head;
VERIFY(slab_inrange(sp, buf) && sp == slab_get(buf));
sp->sl_head = buf->obj_next;
/* Increment slab reference */
sp->sl_refcnt++;
VERIFY(sp->sl_head != NULL || sp->sl_refcnt == sp->sl_chunks);
if (sp->sl_head != NULL && !slab_inrange(sp, sp->sl_head)) {
slab_nextptr_panic(sp, sp->sl_head);
/* In case sl_head is in the map but not in the slab */
VERIFY(slab_inrange(sp, sp->sl_head));
/* NOTREACHED */
}
if (mclaudit != NULL) {
mcache_audit_t *mca = mcl_audit_buf2mca(class, buf);
mca->mca_uflags = 0;
/* Save contents on mbuf objects only */
if (class == MC_MBUF) {
mca->mca_uflags |= MB_SCVALID;
}
}
if (class == MC_CL) {
mbstat.m_clfree = (--m_infree(MC_CL)) + m_infree(MC_MBUF_CL);
/*
* A 2K cluster slab can have at most NCLPG references.
*/
VERIFY(sp->sl_refcnt >= 1 && sp->sl_refcnt <= NCLPG &&
sp->sl_chunks == NCLPG && sp->sl_len == PAGE_SIZE);
VERIFY(sp->sl_refcnt < NCLPG || sp->sl_head == NULL);
} else if (class == MC_BIGCL) {
mbstat.m_bigclfree = (--m_infree(MC_BIGCL)) +
m_infree(MC_MBUF_BIGCL);
/*
* A 4K cluster slab can have NBCLPG references.
*/
VERIFY(sp->sl_refcnt >= 1 && sp->sl_chunks == NBCLPG &&
sp->sl_len == PAGE_SIZE &&
(sp->sl_refcnt < NBCLPG || sp->sl_head == NULL));
} else if (class == MC_16KCL) {
mcl_slab_t *nsp;
int k;
--m_infree(MC_16KCL);
VERIFY(sp->sl_refcnt == 1 && sp->sl_chunks == 1 &&
sp->sl_len == m_maxsize(class) && sp->sl_head == NULL);
/*
* Increment 2nd-Nth slab reference, where N is NSLABSP16KB.
* A 16KB big cluster takes NSLABSP16KB slabs, each having at
* most 1 reference.
*/
for (nsp = sp, k = 1; k < NSLABSP16KB; k++) {
nsp = nsp->sl_next;
/* Next slab must already be present */
VERIFY(nsp != NULL);
nsp->sl_refcnt++;
VERIFY(!slab_is_detached(nsp));
VERIFY(nsp->sl_class == MC_16KCL &&
nsp->sl_flags == (SLF_MAPPED | SLF_PARTIAL) &&
nsp->sl_refcnt == 1 && nsp->sl_chunks == 0 &&
nsp->sl_len == 0 && nsp->sl_base == sp->sl_base &&
nsp->sl_head == NULL);
}
} else {
VERIFY(class == MC_MBUF);
--m_infree(MC_MBUF);
/*
* If auditing is turned on, this check is
* deferred until later in mbuf_slab_audit().
*/
if (mclaudit == NULL) {
mbuf_mcheck((struct mbuf *)buf);
}
/*
* Since we have incremented the reference count above,
* an mbuf slab (formerly a 4KB cluster slab that was cut
* up into mbufs) must have a reference count between 1
* and NMBPG at this point.
*/
VERIFY(sp->sl_refcnt >= 1 && sp->sl_refcnt <= NMBPG &&
sp->sl_chunks == NMBPG &&
sp->sl_len == PAGE_SIZE);
VERIFY(sp->sl_refcnt < NMBPG || sp->sl_head == NULL);
}
/* If empty, remove this slab from the class's freelist */
if (sp->sl_head == NULL) {
VERIFY(class != MC_MBUF || sp->sl_refcnt == NMBPG);
VERIFY(class != MC_CL || sp->sl_refcnt == NCLPG);
VERIFY(class != MC_BIGCL || sp->sl_refcnt == NBCLPG);
slab_remove(sp, class);
}
return buf;
}
/*
* Place a slab of object(s) back into a class's slab list.
*/
static void
slab_free(mbuf_class_t class, mcache_obj_t *buf)
{
mcl_slab_t *sp;
boolean_t reinit_supercl = false;
mbuf_class_t super_class;
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
VERIFY(buf->obj_next == NULL);
/*
* Synchronizing with m_clalloc, as it reads m_total, while we here
* are modifying m_total.
*/
while (mb_clalloc_busy) {
mb_clalloc_waiters++;
(void) msleep(mb_clalloc_waitchan, mbuf_mlock,
(PZERO - 1), "m_clalloc", NULL);
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
}
/* We are busy now; tell everyone else to go away */
mb_clalloc_busy = TRUE;
sp = slab_get(buf);
VERIFY(sp->sl_class == class && slab_inrange(sp, buf) &&
(sp->sl_flags & (SLF_MAPPED | SLF_PARTIAL)) == SLF_MAPPED);
/* Decrement slab reference */
sp->sl_refcnt--;
if (class == MC_CL) {
VERIFY(IS_P2ALIGNED(buf, MCLBYTES));
/*
* A slab that has been splitted for 2KB clusters can have
* at most 1 outstanding reference at this point.
*/
VERIFY(sp->sl_refcnt >= 0 && sp->sl_refcnt <= (NCLPG - 1) &&
sp->sl_chunks == NCLPG && sp->sl_len == PAGE_SIZE);
VERIFY(sp->sl_refcnt < (NCLPG - 1) ||
(slab_is_detached(sp) && sp->sl_head == NULL));
} else if (class == MC_BIGCL) {
VERIFY(IS_P2ALIGNED(buf, MBIGCLBYTES));
/* A 4KB cluster slab can have NBCLPG references at most */
VERIFY(sp->sl_refcnt >= 0 && sp->sl_chunks == NBCLPG);
VERIFY(sp->sl_refcnt < (NBCLPG - 1) ||
(slab_is_detached(sp) && sp->sl_head == NULL));
} else if (class == MC_16KCL) {
mcl_slab_t *nsp;
int k;
/*
* A 16KB cluster takes NSLABSP16KB slabs, all must
* now have 0 reference.
*/
VERIFY(IS_P2ALIGNED(buf, PAGE_SIZE));
VERIFY(sp->sl_refcnt == 0 && sp->sl_chunks == 1 &&
sp->sl_len == m_maxsize(class) && sp->sl_head == NULL);
VERIFY(slab_is_detached(sp));
for (nsp = sp, k = 1; k < NSLABSP16KB; k++) {
nsp = nsp->sl_next;
/* Next slab must already be present */
VERIFY(nsp != NULL);
nsp->sl_refcnt--;
VERIFY(slab_is_detached(nsp));
VERIFY(nsp->sl_class == MC_16KCL &&
(nsp->sl_flags & (SLF_MAPPED | SLF_PARTIAL)) &&
nsp->sl_refcnt == 0 && nsp->sl_chunks == 0 &&
nsp->sl_len == 0 && nsp->sl_base == sp->sl_base &&
nsp->sl_head == NULL);
}
} else {
/*
* A slab that has been splitted for mbufs has at most
* NMBPG reference counts. Since we have decremented
* one reference above, it must now be between 0 and
* NMBPG-1.
*/
VERIFY(class == MC_MBUF);
VERIFY(sp->sl_refcnt >= 0 &&
sp->sl_refcnt <= (NMBPG - 1) &&
sp->sl_chunks == NMBPG &&
sp->sl_len == PAGE_SIZE);
VERIFY(sp->sl_refcnt < (NMBPG - 1) ||
(slab_is_detached(sp) && sp->sl_head == NULL));
}
/*
* When auditing is enabled, ensure that the buffer still
* contains the free pattern. Otherwise it got corrupted
* while at the CPU cache layer.
*/
if (mclaudit != NULL) {
mcache_audit_t *mca = mcl_audit_buf2mca(class, buf);
if (mclverify) {
mcache_audit_free_verify(mca, buf, 0,
m_maxsize(class));
}
mca->mca_uflags &= ~MB_SCVALID;
}
if (class == MC_CL) {
mbstat.m_clfree = (++m_infree(MC_CL)) + m_infree(MC_MBUF_CL);
buf->obj_next = sp->sl_head;
} else if (class == MC_BIGCL) {
mbstat.m_bigclfree = (++m_infree(MC_BIGCL)) +
m_infree(MC_MBUF_BIGCL);
buf->obj_next = sp->sl_head;
} else if (class == MC_16KCL) {
++m_infree(MC_16KCL);
} else {
++m_infree(MC_MBUF);
buf->obj_next = sp->sl_head;
}
sp->sl_head = buf;
/*
* If a slab has been split to either one which holds 2KB clusters,
* or one which holds mbufs, turn it back to one which holds a
* 4 or 16 KB cluster depending on the page size.
*/
if (m_maxsize(MC_BIGCL) == PAGE_SIZE) {
super_class = MC_BIGCL;
} else {
VERIFY(PAGE_SIZE == m_maxsize(MC_16KCL));
super_class = MC_16KCL;
}
if (class == MC_MBUF && sp->sl_refcnt == 0 &&
m_total(class) >= (m_minlimit(class) + NMBPG) &&
m_total(super_class) < m_maxlimit(super_class)) {
int i = NMBPG;
m_total(MC_MBUF) -= NMBPG;
mbstat.m_mbufs = m_total(MC_MBUF);
m_infree(MC_MBUF) -= NMBPG;
mtype_stat_add(MT_FREE, -((unsigned)NMBPG));
while (i--) {
struct mbuf *m = sp->sl_head;
VERIFY(m != NULL);
sp->sl_head = m->m_next;
m->m_next = NULL;
}
reinit_supercl = true;
} else if (class == MC_CL && sp->sl_refcnt == 0 &&
m_total(class) >= (m_minlimit(class) + NCLPG) &&
m_total(super_class) < m_maxlimit(super_class)) {
int i = NCLPG;
m_total(MC_CL) -= NCLPG;
mbstat.m_clusters = m_total(MC_CL);
m_infree(MC_CL) -= NCLPG;
while (i--) {
union mcluster *c = sp->sl_head;
VERIFY(c != NULL);
sp->sl_head = c->mcl_next;
c->mcl_next = NULL;
}
reinit_supercl = true;
} else if (class == MC_BIGCL && super_class != MC_BIGCL &&
sp->sl_refcnt == 0 &&
m_total(class) >= (m_minlimit(class) + NBCLPG) &&
m_total(super_class) < m_maxlimit(super_class)) {
int i = NBCLPG;
VERIFY(super_class == MC_16KCL);
m_total(MC_BIGCL) -= NBCLPG;
mbstat.m_bigclusters = m_total(MC_BIGCL);
m_infree(MC_BIGCL) -= NBCLPG;
while (i--) {
union mbigcluster *bc = sp->sl_head;
VERIFY(bc != NULL);
sp->sl_head = bc->mbc_next;
bc->mbc_next = NULL;
}
reinit_supercl = true;
}
if (reinit_supercl) {
VERIFY(sp->sl_head == NULL);
VERIFY(m_total(class) >= m_minlimit(class));
slab_remove(sp, class);
/* Reinitialize it as a cluster for the super class */
m_total(super_class)++;
m_infree(super_class)++;
VERIFY(sp->sl_flags == (SLF_MAPPED | SLF_DETACHED) &&
sp->sl_len == PAGE_SIZE && sp->sl_refcnt == 0);
slab_init(sp, super_class, SLF_MAPPED, sp->sl_base,
sp->sl_base, PAGE_SIZE, 0, 1);
if (mclverify) {
mcache_set_pattern(MCACHE_FREE_PATTERN,
(caddr_t)sp->sl_base, sp->sl_len);
}
((mcache_obj_t *)(sp->sl_base))->obj_next = NULL;
if (super_class == MC_BIGCL) {
mbstat.m_bigclusters = m_total(MC_BIGCL);
mbstat.m_bigclfree = m_infree(MC_BIGCL) +
m_infree(MC_MBUF_BIGCL);
}
VERIFY(slab_is_detached(sp));
VERIFY(m_total(super_class) <= m_maxlimit(super_class));
/* And finally switch class */
class = super_class;
}
/* Reinsert the slab to the class's slab list */
if (slab_is_detached(sp)) {
slab_insert(sp, class);
}
/* We're done; let others enter */
mb_clalloc_busy = FALSE;
if (mb_clalloc_waiters > 0) {
mb_clalloc_waiters = 0;
wakeup(mb_clalloc_waitchan);
}
}
/*
* Common allocator for rudimentary objects called by the CPU cache layer
* during an allocation request whenever there is no available element in the
* bucket layer. It returns one or more elements from the appropriate global
* freelist. If the freelist is empty, it will attempt to populate it and
* retry the allocation.
*/
static unsigned int
mbuf_slab_alloc(void *arg, mcache_obj_t ***plist, unsigned int num, int wait)
{
mbuf_class_t class = (mbuf_class_t)arg;
unsigned int need = num;
mcache_obj_t **list = *plist;
ASSERT(MBUF_CLASS_VALID(class) && !MBUF_CLASS_COMPOSITE(class));
ASSERT(need > 0);
lck_mtx_lock(mbuf_mlock);
for (;;) {
if ((*list = slab_alloc(class, wait)) != NULL) {
(*list)->obj_next = NULL;
list = *plist = &(*list)->obj_next;
if (--need == 0) {
/*
* If the number of elements in freelist has
* dropped below low watermark, asynchronously
* populate the freelist now rather than doing
* it later when we run out of elements.
*/
if (!mbuf_cached_above(class, wait) &&
m_infree(class) < (m_total(class) >> 5)) {
(void) freelist_populate(class, 1,
M_DONTWAIT);
}
break;
}
} else {
VERIFY(m_infree(class) == 0 || class == MC_CL);
(void) freelist_populate(class, 1,
(wait & MCR_NOSLEEP) ? M_DONTWAIT : M_WAIT);
if (m_infree(class) > 0) {
continue;
}
/* Check if there's anything at the cache layer */
if (mbuf_cached_above(class, wait)) {
break;
}
/* watchdog checkpoint */
mbuf_watchdog();
/* We have nothing and cannot block; give up */
if (wait & MCR_NOSLEEP) {
if (!(wait & MCR_TRYHARD)) {
m_fail_cnt(class)++;
mbstat.m_drops++;
break;
}
}
/*
* If the freelist is still empty and the caller is
* willing to be blocked, sleep on the wait channel
* until an element is available. Otherwise, if
* MCR_TRYHARD is set, do our best to satisfy the
* request without having to go to sleep.
*/
if (mbuf_worker_ready &&
mbuf_sleep(class, need, wait)) {
break;
}
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
}
}
m_alloc_cnt(class) += num - need;
lck_mtx_unlock(mbuf_mlock);
return num - need;
}
/*
* Common de-allocator for rudimentary objects called by the CPU cache
* layer when one or more elements need to be returned to the appropriate
* global freelist.
*/
static void
mbuf_slab_free(void *arg, mcache_obj_t *list, __unused int purged)
{
mbuf_class_t class = (mbuf_class_t)arg;
mcache_obj_t *nlist;
unsigned int num = 0;
int w;
ASSERT(MBUF_CLASS_VALID(class) && !MBUF_CLASS_COMPOSITE(class));
lck_mtx_lock(mbuf_mlock);
for (;;) {
nlist = list->obj_next;
list->obj_next = NULL;
slab_free(class, list);
++num;
if ((list = nlist) == NULL) {
break;
}
}
m_free_cnt(class) += num;
if ((w = mb_waiters) > 0) {
mb_waiters = 0;
}
if (w) {
mbwdog_logger("waking up all threads");
}
lck_mtx_unlock(mbuf_mlock);
if (w != 0) {
wakeup(mb_waitchan);
}
}
/*
* Common auditor for rudimentary objects called by the CPU cache layer
* during an allocation or free request. For the former, this is called
* after the objects are obtained from either the bucket or slab layer
* and before they are returned to the caller. For the latter, this is
* called immediately during free and before placing the objects into
* the bucket or slab layer.
*/
static void
mbuf_slab_audit(void *arg, mcache_obj_t *list, boolean_t alloc)
{
mbuf_class_t class = (mbuf_class_t)arg;
mcache_audit_t *mca;
ASSERT(MBUF_CLASS_VALID(class) && !MBUF_CLASS_COMPOSITE(class));
while (list != NULL) {
lck_mtx_lock(mbuf_mlock);
mca = mcl_audit_buf2mca(class, list);
/* Do the sanity checks */
if (class == MC_MBUF) {
mcl_audit_mbuf(mca, list, FALSE, alloc);
ASSERT(mca->mca_uflags & MB_SCVALID);
} else {
mcl_audit_cluster(mca, list, m_maxsize(class),
alloc, TRUE);
ASSERT(!(mca->mca_uflags & MB_SCVALID));
}
/* Record this transaction */
if (mcltrace) {
mcache_buffer_log(mca, list, m_cache(class), &mb_start);
}
if (alloc) {
mca->mca_uflags |= MB_INUSE;
} else {
mca->mca_uflags &= ~MB_INUSE;
}
/* Unpair the object (unconditionally) */
mca->mca_uptr = NULL;
lck_mtx_unlock(mbuf_mlock);
list = list->obj_next;
}
}
/*
* Common notify routine for all caches. It is called by mcache when
* one or more objects get freed. We use this indication to trigger
* the wakeup of any sleeping threads so that they can retry their
* allocation requests.
*/
static void
mbuf_slab_notify(void *arg, u_int32_t reason)
{
mbuf_class_t class = (mbuf_class_t)arg;
int w;
ASSERT(MBUF_CLASS_VALID(class));
if (reason != MCN_RETRYALLOC) {
return;
}
lck_mtx_lock(mbuf_mlock);
if ((w = mb_waiters) > 0) {
m_notified(class)++;
mb_waiters = 0;
}
if (w) {
mbwdog_logger("waking up all threads");
}
lck_mtx_unlock(mbuf_mlock);
if (w != 0) {
wakeup(mb_waitchan);
}
}
/*
* Obtain object(s) from the composite class's freelist.
*/
static unsigned int
cslab_alloc(mbuf_class_t class, mcache_obj_t ***plist, unsigned int num)
{
unsigned int need = num;
mcl_slab_t *sp, *clsp, *nsp;
struct mbuf *m;
mcache_obj_t **list = *plist;
void *cl;
VERIFY(need > 0);
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
/* Get what we can from the freelist */
while ((*list = m_cobjlist(class)) != NULL) {
MRANGE(*list);
m = (struct mbuf *)*list;
sp = slab_get(m);
cl = m->m_ext.ext_buf;
clsp = slab_get(cl);
VERIFY(m->m_flags == M_EXT && cl != NULL);
VERIFY(m_get_rfa(m) != NULL && MBUF_IS_COMPOSITE(m));
if (class == MC_MBUF_CL) {
VERIFY(clsp->sl_refcnt >= 1 &&
clsp->sl_refcnt <= NCLPG);
} else {
VERIFY(clsp->sl_refcnt >= 1 &&
clsp->sl_refcnt <= NBCLPG);
}
if (class == MC_MBUF_16KCL) {
int k;
for (nsp = clsp, k = 1; k < NSLABSP16KB; k++) {
nsp = nsp->sl_next;
/* Next slab must already be present */
VERIFY(nsp != NULL);
VERIFY(nsp->sl_refcnt == 1);
}
}
if ((m_cobjlist(class) = (*list)->obj_next) != NULL &&
!MBUF_IN_MAP(m_cobjlist(class))) {
slab_nextptr_panic(sp, m_cobjlist(class));
/* NOTREACHED */
}
(*list)->obj_next = NULL;
list = *plist = &(*list)->obj_next;
if (--need == 0) {
break;
}
}
m_infree(class) -= (num - need);
return num - need;
}
/*
* Place object(s) back into a composite class's freelist.
*/
static unsigned int
cslab_free(mbuf_class_t class, mcache_obj_t *list, int purged)
{
mcache_obj_t *o, *tail;
unsigned int num = 0;
struct mbuf *m, *ms;
mcache_audit_t *mca = NULL;
mcache_obj_t *ref_list = NULL;
mcl_slab_t *clsp, *nsp;
void *cl;
mbuf_class_t cl_class;
ASSERT(MBUF_CLASS_VALID(class) && MBUF_CLASS_COMPOSITE(class));
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
if (class == MC_MBUF_CL) {
cl_class = MC_CL;
} else if (class == MC_MBUF_BIGCL) {
cl_class = MC_BIGCL;
} else {
VERIFY(class == MC_MBUF_16KCL);
cl_class = MC_16KCL;
}
o = tail = list;
while ((m = ms = (struct mbuf *)o) != NULL) {
mcache_obj_t *rfa, *nexto = o->obj_next;
/* Do the mbuf sanity checks */
if (mclaudit != NULL) {
mca = mcl_audit_buf2mca(MC_MBUF, (mcache_obj_t *)m);
if (mclverify) {
mcache_audit_free_verify(mca, m, 0,
m_maxsize(MC_MBUF));
}
ms = MCA_SAVED_MBUF_PTR(mca);
}
/* Do the cluster sanity checks */
cl = ms->m_ext.ext_buf;
clsp = slab_get(cl);
if (mclverify) {
size_t size = m_maxsize(cl_class);
mcache_audit_free_verify(mcl_audit_buf2mca(cl_class,
(mcache_obj_t *)cl), cl, 0, size);
}
VERIFY(ms->m_type == MT_FREE);
VERIFY(ms->m_flags == M_EXT);
VERIFY(m_get_rfa(ms) != NULL && MBUF_IS_COMPOSITE(ms));
if (cl_class == MC_CL) {
VERIFY(clsp->sl_refcnt >= 1 &&
clsp->sl_refcnt <= NCLPG);
} else {
VERIFY(clsp->sl_refcnt >= 1 &&
clsp->sl_refcnt <= NBCLPG);
}
if (cl_class == MC_16KCL) {
int k;
for (nsp = clsp, k = 1; k < NSLABSP16KB; k++) {
nsp = nsp->sl_next;
/* Next slab must already be present */
VERIFY(nsp != NULL);
VERIFY(nsp->sl_refcnt == 1);
}
}
/*
* If we're asked to purge, restore the actual mbuf using
* contents of the shadow structure (if auditing is enabled)
* and clear EXTF_COMPOSITE flag from the mbuf, as we are
* about to free it and the attached cluster into their caches.
*/
if (purged) {
/* Restore constructed mbuf fields */
if (mclaudit != NULL) {
mcl_audit_restore_mbuf(m, mca, TRUE);
}
MEXT_MINREF(m) = 0;
MEXT_REF(m) = 0;
MEXT_PREF(m) = 0;
MEXT_FLAGS(m) = 0;
MEXT_PRIV(m) = 0;
MEXT_PMBUF(m) = NULL;
rfa = (mcache_obj_t *)(void *)m_get_rfa(m);
m_set_ext(m, NULL, NULL, NULL);
rfa->obj_next = ref_list;
ref_list = rfa;
m->m_type = MT_FREE;
m->m_flags = m->m_len = 0;
m->m_next = m->m_nextpkt = NULL;
/* Save mbuf fields and make auditing happy */
if (mclaudit != NULL) {
mcl_audit_mbuf(mca, o, FALSE, FALSE);
}
VERIFY(m_total(class) > 0);
m_total(class)--;
/* Free the mbuf */
o->obj_next = NULL;
slab_free(MC_MBUF, o);
/* And free the cluster */
((mcache_obj_t *)cl)->obj_next = NULL;
if (class == MC_MBUF_CL) {
slab_free(MC_CL, cl);
} else if (class == MC_MBUF_BIGCL) {
slab_free(MC_BIGCL, cl);
} else {
slab_free(MC_16KCL, cl);
}
}
++num;
tail = o;
o = nexto;
}
if (!purged) {
tail->obj_next = m_cobjlist(class);
m_cobjlist(class) = list;
m_infree(class) += num;
} else if (ref_list != NULL) {
mcache_free_ext(ref_cache, ref_list);
}
return num;
}
/*
* Common allocator for composite objects called by the CPU cache layer
* during an allocation request whenever there is no available element in
* the bucket layer. It returns one or more composite elements from the
* appropriate global freelist. If the freelist is empty, it will attempt
* to obtain the rudimentary objects from their caches and construct them
* into composite mbuf + cluster objects.
*/
static unsigned int
mbuf_cslab_alloc(void *arg, mcache_obj_t ***plist, unsigned int needed,
int wait)
{
mbuf_class_t class = (mbuf_class_t)arg;
mbuf_class_t cl_class = 0;
unsigned int num = 0, cnum = 0, want = needed;
mcache_obj_t *ref_list = NULL;
mcache_obj_t *mp_list = NULL;
mcache_obj_t *clp_list = NULL;
mcache_obj_t **list;
struct ext_ref *rfa;
struct mbuf *m;
void *cl;
ASSERT(MBUF_CLASS_VALID(class) && MBUF_CLASS_COMPOSITE(class));
ASSERT(needed > 0);
/* There should not be any slab for this class */
VERIFY(m_slab_cnt(class) == 0 &&
m_slablist(class).tqh_first == NULL &&
m_slablist(class).tqh_last == NULL);
lck_mtx_lock(mbuf_mlock);
/* Try using the freelist first */
num = cslab_alloc(class, plist, needed);
list = *plist;
if (num == needed) {
m_alloc_cnt(class) += num;
lck_mtx_unlock(mbuf_mlock);
return needed;
}
lck_mtx_unlock(mbuf_mlock);
/*
* We could not satisfy the request using the freelist alone;
* allocate from the appropriate rudimentary caches and use
* whatever we can get to construct the composite objects.
*/
needed -= num;
/*
* Mark these allocation requests as coming from a composite cache.
* Also, if the caller is willing to be blocked, mark the request
* with MCR_FAILOK such that we don't end up sleeping at the mbuf
* slab layer waiting for the individual object when one or more
* of the already-constructed composite objects are available.
*/
wait |= MCR_COMP;
if (!(wait & MCR_NOSLEEP)) {
wait |= MCR_FAILOK;
}
/* allocate mbufs */
needed = mcache_alloc_ext(m_cache(MC_MBUF), &mp_list, needed, wait);
if (needed == 0) {
ASSERT(mp_list == NULL);
goto fail;
}
/* allocate clusters */
if (class == MC_MBUF_CL) {
cl_class = MC_CL;
} else if (class == MC_MBUF_BIGCL) {
cl_class = MC_BIGCL;
} else {
VERIFY(class == MC_MBUF_16KCL);
cl_class = MC_16KCL;
}
needed = mcache_alloc_ext(m_cache(cl_class), &clp_list, needed, wait);
if (needed == 0) {
ASSERT(clp_list == NULL);
goto fail;
}
needed = mcache_alloc_ext(ref_cache, &ref_list, needed, wait);
if (needed == 0) {
ASSERT(ref_list == NULL);
goto fail;
}
/*
* By this time "needed" is MIN(mbuf, cluster, ref). Any left
* overs will get freed accordingly before we return to caller.
*/
for (cnum = 0; cnum < needed; cnum++) {
struct mbuf *ms;
m = ms = (struct mbuf *)mp_list;
mp_list = mp_list->obj_next;
cl = clp_list;
clp_list = clp_list->obj_next;
((mcache_obj_t *)cl)->obj_next = NULL;
rfa = (struct ext_ref *)ref_list;
ref_list = ref_list->obj_next;
((mcache_obj_t *)(void *)rfa)->obj_next = NULL;
/*
* If auditing is enabled, construct the shadow mbuf
* in the audit structure instead of in the actual one.
* mbuf_cslab_audit() will take care of restoring the
* contents after the integrity check.
*/
if (mclaudit != NULL) {
mcache_audit_t *mca, *cl_mca;
lck_mtx_lock(mbuf_mlock);
mca = mcl_audit_buf2mca(MC_MBUF, (mcache_obj_t *)m);
ms = MCA_SAVED_MBUF_PTR(mca);
cl_mca = mcl_audit_buf2mca(cl_class,
(mcache_obj_t *)cl);
/*
* Pair them up. Note that this is done at the time
* the mbuf+cluster objects are constructed. This
* information should be treated as "best effort"
* debugging hint since more than one mbufs can refer
* to a cluster. In that case, the cluster might not
* be freed along with the mbuf it was paired with.
*/
mca->mca_uptr = cl_mca;
cl_mca->mca_uptr = mca;
ASSERT(mca->mca_uflags & MB_SCVALID);
ASSERT(!(cl_mca->mca_uflags & MB_SCVALID));
lck_mtx_unlock(mbuf_mlock);
/* Technically, they are in the freelist */
if (mclverify) {
size_t size;
mcache_set_pattern(MCACHE_FREE_PATTERN, m,
m_maxsize(MC_MBUF));
if (class == MC_MBUF_CL) {
size = m_maxsize(MC_CL);
} else if (class == MC_MBUF_BIGCL) {
size = m_maxsize(MC_BIGCL);
} else {
size = m_maxsize(MC_16KCL);
}
mcache_set_pattern(MCACHE_FREE_PATTERN, cl,
size);
}
}
mbuf_init(ms, 0, MT_FREE);
if (class == MC_MBUF_16KCL) {
MBUF_16KCL_INIT(ms, cl, rfa, 0, EXTF_COMPOSITE);
} else if (class == MC_MBUF_BIGCL) {
MBUF_BIGCL_INIT(ms, cl, rfa, 0, EXTF_COMPOSITE);
} else {
MBUF_CL_INIT(ms, cl, rfa, 0, EXTF_COMPOSITE);
}
VERIFY(ms->m_flags == M_EXT);
VERIFY(m_get_rfa(ms) != NULL && MBUF_IS_COMPOSITE(ms));
*list = (mcache_obj_t *)m;
(*list)->obj_next = NULL;
list = *plist = &(*list)->obj_next;
}
fail:
/*
* Free up what's left of the above.
*/
if (mp_list != NULL) {
mcache_free_ext(m_cache(MC_MBUF), mp_list);
}
if (clp_list != NULL) {
mcache_free_ext(m_cache(cl_class), clp_list);
}
if (ref_list != NULL) {
mcache_free_ext(ref_cache, ref_list);
}
lck_mtx_lock(mbuf_mlock);
if (num > 0 || cnum > 0) {
m_total(class) += cnum;
VERIFY(m_total(class) <= m_maxlimit(class));
m_alloc_cnt(class) += num + cnum;
}
if ((num + cnum) < want) {
m_fail_cnt(class) += (want - (num + cnum));
}
lck_mtx_unlock(mbuf_mlock);
return num + cnum;
}
/*
* Common de-allocator for composite objects called by the CPU cache
* layer when one or more elements need to be returned to the appropriate
* global freelist.
*/
static void
mbuf_cslab_free(void *arg, mcache_obj_t *list, int purged)
{
mbuf_class_t class = (mbuf_class_t)arg;
unsigned int num;
int w;
ASSERT(MBUF_CLASS_VALID(class) && MBUF_CLASS_COMPOSITE(class));
lck_mtx_lock(mbuf_mlock);
num = cslab_free(class, list, purged);
m_free_cnt(class) += num;
if ((w = mb_waiters) > 0) {
mb_waiters = 0;
}
if (w) {
mbwdog_logger("waking up all threads");
}
lck_mtx_unlock(mbuf_mlock);
if (w != 0) {
wakeup(mb_waitchan);
}
}
/*
* Common auditor for composite objects called by the CPU cache layer
* during an allocation or free request. For the former, this is called
* after the objects are obtained from either the bucket or slab layer
* and before they are returned to the caller. For the latter, this is
* called immediately during free and before placing the objects into
* the bucket or slab layer.
*/
static void
mbuf_cslab_audit(void *arg, mcache_obj_t *list, boolean_t alloc)
{
mbuf_class_t class = (mbuf_class_t)arg, cl_class;
mcache_audit_t *mca;
struct mbuf *m, *ms;
mcl_slab_t *clsp, *nsp;
size_t cl_size;
void *cl;
ASSERT(MBUF_CLASS_VALID(class) && MBUF_CLASS_COMPOSITE(class));
if (class == MC_MBUF_CL) {
cl_class = MC_CL;
} else if (class == MC_MBUF_BIGCL) {
cl_class = MC_BIGCL;
} else {
cl_class = MC_16KCL;
}
cl_size = m_maxsize(cl_class);
while ((m = ms = (struct mbuf *)list) != NULL) {
lck_mtx_lock(mbuf_mlock);
/* Do the mbuf sanity checks and record its transaction */
mca = mcl_audit_buf2mca(MC_MBUF, (mcache_obj_t *)m);
mcl_audit_mbuf(mca, m, TRUE, alloc);
if (mcltrace) {
mcache_buffer_log(mca, m, m_cache(class), &mb_start);
}
if (alloc) {
mca->mca_uflags |= MB_COMP_INUSE;
} else {
mca->mca_uflags &= ~MB_COMP_INUSE;
}
/*
* Use the shadow mbuf in the audit structure if we are
* freeing, since the contents of the actual mbuf has been
* pattern-filled by the above call to mcl_audit_mbuf().
*/
if (!alloc && mclverify) {
ms = MCA_SAVED_MBUF_PTR(mca);
}
/* Do the cluster sanity checks and record its transaction */
cl = ms->m_ext.ext_buf;
clsp = slab_get(cl);
VERIFY(ms->m_flags == M_EXT && cl != NULL);
VERIFY(m_get_rfa(ms) != NULL && MBUF_IS_COMPOSITE(ms));
if (class == MC_MBUF_CL) {
VERIFY(clsp->sl_refcnt >= 1 &&
clsp->sl_refcnt <= NCLPG);
} else {
VERIFY(clsp->sl_refcnt >= 1 &&
clsp->sl_refcnt <= NBCLPG);
}
if (class == MC_MBUF_16KCL) {
int k;
for (nsp = clsp, k = 1; k < NSLABSP16KB; k++) {
nsp = nsp->sl_next;
/* Next slab must already be present */
VERIFY(nsp != NULL);
VERIFY(nsp->sl_refcnt == 1);
}
}
mca = mcl_audit_buf2mca(cl_class, cl);
mcl_audit_cluster(mca, cl, cl_size, alloc, FALSE);
if (mcltrace) {
mcache_buffer_log(mca, cl, m_cache(class), &mb_start);
}
if (alloc) {
mca->mca_uflags |= MB_COMP_INUSE;
} else {
mca->mca_uflags &= ~MB_COMP_INUSE;
}
lck_mtx_unlock(mbuf_mlock);
list = list->obj_next;
}
}
static void
m_vm_error_stats(uint32_t *cnt, uint64_t *ts, uint64_t *size,
uint64_t alloc_size, kern_return_t error)
{
*cnt = *cnt + 1;
*ts = net_uptime();
if (size) {
*size = alloc_size;
}
switch (error) {
case KERN_SUCCESS:
break;
case KERN_INVALID_ARGUMENT:
mb_kmem_stats[0]++;
break;
case KERN_INVALID_ADDRESS:
mb_kmem_stats[1]++;
break;
case KERN_RESOURCE_SHORTAGE:
mb_kmem_stats[2]++;
break;
case KERN_NO_SPACE:
mb_kmem_stats[3]++;
break;
case KERN_FAILURE:
mb_kmem_stats[4]++;
break;
default:
mb_kmem_stats[5]++;
break;
}
}
static vm_offset_t
kmem_mb_alloc(vm_map_t mbmap, int size, int physContig, kern_return_t *err)
{
vm_offset_t addr = 0;
kern_return_t kr = KERN_SUCCESS;
if (!physContig) {
kr = kmem_alloc(mbmap, &addr, size,
KMA_KOBJECT | KMA_LOMEM, VM_KERN_MEMORY_MBUF);
} else {
kr = kmem_alloc_contig(mbmap, &addr, size, PAGE_MASK, 0xfffff,
0, KMA_KOBJECT | KMA_LOMEM, VM_KERN_MEMORY_MBUF);
}
if (kr != KERN_SUCCESS) {
addr = 0;
}
if (err) {
*err = kr;
}
return addr;
}
/*
* Allocate some number of mbuf clusters and place on cluster freelist.
*/
static int
m_clalloc(const u_int32_t num, const int wait, const u_int32_t bufsize)
{
int i, count = 0;
vm_size_t size = 0;
int numpages = 0, large_buffer;
vm_offset_t page = 0;
mcache_audit_t *mca_list = NULL;
mcache_obj_t *con_list = NULL;
mcl_slab_t *sp;
mbuf_class_t class;
kern_return_t error;
/* Set if a buffer allocation needs allocation of multiple pages */
large_buffer = ((bufsize == m_maxsize(MC_16KCL)) &&
PAGE_SIZE < M16KCLBYTES);
VERIFY(bufsize == m_maxsize(MC_BIGCL) ||
bufsize == m_maxsize(MC_16KCL));
VERIFY((bufsize == PAGE_SIZE) ||
(bufsize > PAGE_SIZE && bufsize == m_maxsize(MC_16KCL)));
if (bufsize == m_size(MC_BIGCL)) {
class = MC_BIGCL;
} else {
class = MC_16KCL;
}
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
/*
* Multiple threads may attempt to populate the cluster map one
* after another. Since we drop the lock below prior to acquiring
* the physical page(s), our view of the cluster map may no longer
* be accurate, and we could end up over-committing the pages beyond
* the maximum allowed for each class. To prevent it, this entire
* operation (including the page mapping) is serialized.
*/
while (mb_clalloc_busy) {
mb_clalloc_waiters++;
(void) msleep(mb_clalloc_waitchan, mbuf_mlock,
(PZERO - 1), "m_clalloc", NULL);
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
}
/* We are busy now; tell everyone else to go away */
mb_clalloc_busy = TRUE;
/*
* Honor the caller's wish to block or not block. We have a way
* to grow the pool asynchronously using the mbuf worker thread.
*/
i = m_howmany(num, bufsize);
if (i <= 0 || (wait & M_DONTWAIT)) {
goto out;
}
lck_mtx_unlock(mbuf_mlock);
size = round_page(i * bufsize);
page = kmem_mb_alloc(mb_map, size, large_buffer, &error);
/*
* If we did ask for "n" 16KB physically contiguous chunks
* and didn't get them, then please try again without this
* restriction.
*/
net_update_uptime();
if (large_buffer && page == 0) {
m_vm_error_stats(&mb_kmem_contig_failed,
&mb_kmem_contig_failed_ts,
&mb_kmem_contig_failed_size,
size, error);
page = kmem_mb_alloc(mb_map, size, 0, &error);
}
if (page == 0) {
m_vm_error_stats(&mb_kmem_failed,
&mb_kmem_failed_ts,
&mb_kmem_failed_size,
size, error);
#if PAGE_SIZE == 4096
if (bufsize == m_maxsize(MC_BIGCL)) {
#else
if (bufsize >= m_maxsize(MC_BIGCL)) {
#endif
/* Try for 1 page if failed */
size = PAGE_SIZE;
page = kmem_mb_alloc(mb_map, size, 0, &error);
if (page == 0) {
m_vm_error_stats(&mb_kmem_one_failed,
&mb_kmem_one_failed_ts,
NULL, size, error);
}
}
if (page == 0) {
lck_mtx_lock(mbuf_mlock);
goto out;
}
}
VERIFY(IS_P2ALIGNED(page, PAGE_SIZE));
numpages = size / PAGE_SIZE;
/* If auditing is enabled, allocate the audit structures now */
if (mclaudit != NULL) {
int needed;
/*
* Yes, I realize this is a waste of memory for clusters
* that never get transformed into mbufs, as we may end
* up with NMBPG-1 unused audit structures per cluster.
* But doing so tremendously simplifies the allocation
* strategy, since at this point we are not holding the
* mbuf lock and the caller is okay to be blocked.
*/
if (bufsize == PAGE_SIZE) {
needed = numpages * NMBPG;
i = mcache_alloc_ext(mcl_audit_con_cache,
&con_list, needed, MCR_SLEEP);
VERIFY(con_list != NULL && i == needed);
} else {
/*
* if multiple 4K pages are being used for a
* 16K cluster
*/
needed = numpages / NSLABSP16KB;
}
i = mcache_alloc_ext(mcache_audit_cache,
(mcache_obj_t **)&mca_list, needed, MCR_SLEEP);
VERIFY(mca_list != NULL && i == needed);
}
lck_mtx_lock(mbuf_mlock);
for (i = 0; i < numpages; i++, page += PAGE_SIZE) {
ppnum_t offset =
((unsigned char *)page - mbutl) >> PAGE_SHIFT;
ppnum_t new_page = pmap_find_phys(kernel_pmap, page);
/*
* If there is a mapper the appropriate I/O page is
* returned; zero out the page to discard its past
* contents to prevent exposing leftover kernel memory.
*/
VERIFY(offset < mcl_pages);
if (mcl_paddr_base != 0) {
bzero((void *)(uintptr_t) page, PAGE_SIZE);
new_page = IOMapperInsertPage(mcl_paddr_base,
offset, new_page);
}
mcl_paddr[offset] = new_page;
/* Pattern-fill this fresh page */
if (mclverify) {
mcache_set_pattern(MCACHE_FREE_PATTERN,
(caddr_t)page, PAGE_SIZE);
}
if (bufsize == PAGE_SIZE) {
mcache_obj_t *buf;
/* One for the entire page */
sp = slab_get((void *)page);
if (mclaudit != NULL) {
mcl_audit_init((void *)page,
&mca_list, &con_list,
AUDIT_CONTENTS_SIZE, NMBPG);
}
VERIFY(sp->sl_refcnt == 0 && sp->sl_flags == 0);
slab_init(sp, class, SLF_MAPPED, (void *)page,
(void *)page, PAGE_SIZE, 0, 1);
buf = (mcache_obj_t *)page;
buf->obj_next = NULL;
/* Insert this slab */
slab_insert(sp, class);
/* Update stats now since slab_get drops the lock */
++m_infree(class);
++m_total(class);
VERIFY(m_total(class) <= m_maxlimit(class));
if (class == MC_BIGCL) {
mbstat.m_bigclfree = m_infree(MC_BIGCL) +
m_infree(MC_MBUF_BIGCL);
mbstat.m_bigclusters = m_total(MC_BIGCL);
}
++count;
} else if ((bufsize > PAGE_SIZE) &&
(i % NSLABSP16KB) == 0) {
union m16kcluster *m16kcl = (union m16kcluster *)page;
mcl_slab_t *nsp;
int k;
/* One for the entire 16KB */
sp = slab_get(m16kcl);
if (mclaudit != NULL) {
mcl_audit_init(m16kcl, &mca_list, NULL, 0, 1);
}
VERIFY(sp->sl_refcnt == 0 && sp->sl_flags == 0);
slab_init(sp, MC_16KCL, SLF_MAPPED,
m16kcl, m16kcl, bufsize, 0, 1);
m16kcl->m16kcl_next = NULL;
/*
* 2nd-Nth page's slab is part of the first one,
* where N is NSLABSP16KB.
*/
for (k = 1; k < NSLABSP16KB; k++) {
nsp = slab_get(((union mbigcluster *)page) + k);
VERIFY(nsp->sl_refcnt == 0 &&
nsp->sl_flags == 0);
slab_init(nsp, MC_16KCL,
SLF_MAPPED | SLF_PARTIAL,
m16kcl, NULL, 0, 0, 0);
}
/* Insert this slab */
slab_insert(sp, MC_16KCL);
/* Update stats now since slab_get drops the lock */
++m_infree(MC_16KCL);
++m_total(MC_16KCL);
VERIFY(m_total(MC_16KCL) <= m_maxlimit(MC_16KCL));
++count;
}
}
VERIFY(mca_list == NULL && con_list == NULL);
/* We're done; let others enter */
mb_clalloc_busy = FALSE;
if (mb_clalloc_waiters > 0) {
mb_clalloc_waiters = 0;
wakeup(mb_clalloc_waitchan);
}
return count;
out:
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
mtracelarge_register(size);
/* We're done; let others enter */
mb_clalloc_busy = FALSE;
if (mb_clalloc_waiters > 0) {
mb_clalloc_waiters = 0;
wakeup(mb_clalloc_waitchan);
}
/*
* When non-blocking we kick a thread if we have to grow the
* pool or if the number of free clusters is less than requested.
*/
if (i > 0 && mbuf_worker_ready && mbuf_worker_needs_wakeup) {
mbwdog_logger("waking up the worker thread to to grow %s by %d",
m_cname(class), i);
wakeup((caddr_t)&mbuf_worker_needs_wakeup);
mbuf_worker_needs_wakeup = FALSE;
}
if (class == MC_BIGCL) {
if (i > 0) {
/*
* Remember total number of 4KB clusters needed
* at this time.
*/
i += m_total(MC_BIGCL);
if (i > m_region_expand(MC_BIGCL)) {
m_region_expand(MC_BIGCL) = i;
}
}
if (m_infree(MC_BIGCL) >= num) {
return 1;
}
} else {
if (i > 0) {
/*
* Remember total number of 16KB clusters needed
* at this time.
*/
i += m_total(MC_16KCL);
if (i > m_region_expand(MC_16KCL)) {
m_region_expand(MC_16KCL) = i;
}
}
if (m_infree(MC_16KCL) >= num) {
return 1;
}
}
return 0;
}
/*
* Populate the global freelist of the corresponding buffer class.
*/
static int
freelist_populate(mbuf_class_t class, unsigned int num, int wait)
{
mcache_obj_t *o = NULL;
int i, numpages = 0, count;
mbuf_class_t super_class;
VERIFY(class == MC_MBUF || class == MC_CL || class == MC_BIGCL ||
class == MC_16KCL);
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
VERIFY(PAGE_SIZE == m_maxsize(MC_BIGCL) ||
PAGE_SIZE == m_maxsize(MC_16KCL));
if (m_maxsize(class) >= PAGE_SIZE) {
return m_clalloc(num, wait, m_maxsize(class)) != 0;
}
/*
* The rest of the function will allocate pages and will slice
* them up into the right size
*/
numpages = (num * m_size(class) + PAGE_SIZE - 1) / PAGE_SIZE;
/* Currently assume that pages are 4K or 16K */
if (PAGE_SIZE == m_maxsize(MC_BIGCL)) {
super_class = MC_BIGCL;
} else {
super_class = MC_16KCL;
}
i = m_clalloc(numpages, wait, m_maxsize(super_class));
/* how many objects will we cut the page into? */
int numobj = PAGE_SIZE / m_maxsize(class);
for (count = 0; count < numpages; count++) {
/* respect totals, minlimit, maxlimit */
if (m_total(super_class) <= m_minlimit(super_class) ||
m_total(class) >= m_maxlimit(class)) {
break;
}
if ((o = slab_alloc(super_class, wait)) == NULL) {
break;
}
struct mbuf *m = (struct mbuf *)o;
union mcluster *c = (union mcluster *)o;
union mbigcluster *mbc = (union mbigcluster *)o;
mcl_slab_t *sp = slab_get(o);
mcache_audit_t *mca = NULL;
/*
* since one full page will be converted to MC_MBUF or
* MC_CL, verify that the reference count will match that
* assumption
*/
VERIFY(sp->sl_refcnt == 1 && slab_is_detached(sp));
VERIFY((sp->sl_flags & (SLF_MAPPED | SLF_PARTIAL)) == SLF_MAPPED);
/*
* Make sure that the cluster is unmolested
* while in freelist
*/
if (mclverify) {
mca = mcl_audit_buf2mca(super_class,
(mcache_obj_t *)o);
mcache_audit_free_verify(mca,
(mcache_obj_t *)o, 0, m_maxsize(super_class));
}
/* Reinitialize it as an mbuf or 2K or 4K slab */
slab_init(sp, class, sp->sl_flags,
sp->sl_base, NULL, PAGE_SIZE, 0, numobj);
VERIFY(sp->sl_head == NULL);
VERIFY(m_total(super_class) >= 1);
m_total(super_class)--;
if (super_class == MC_BIGCL) {
mbstat.m_bigclusters = m_total(MC_BIGCL);
}
m_total(class) += numobj;
VERIFY(m_total(class) <= m_maxlimit(class));
m_infree(class) += numobj;
i = numobj;
if (class == MC_MBUF) {
mbstat.m_mbufs = m_total(MC_MBUF);
mtype_stat_add(MT_FREE, NMBPG);
while (i--) {
/*
* If auditing is enabled, construct the
* shadow mbuf in the audit structure
* instead of the actual one.
* mbuf_slab_audit() will take care of
* restoring the contents after the
* integrity check.
*/
if (mclaudit != NULL) {
struct mbuf *ms;
mca = mcl_audit_buf2mca(MC_MBUF,
(mcache_obj_t *)m);
ms = MCA_SAVED_MBUF_PTR(mca);
ms->m_type = MT_FREE;
} else {
m->m_type = MT_FREE;
}
m->m_next = sp->sl_head;
sp->sl_head = (void *)m++;
}
} else if (class == MC_CL) { /* MC_CL */
mbstat.m_clfree =
m_infree(MC_CL) + m_infree(MC_MBUF_CL);
mbstat.m_clusters = m_total(MC_CL);
while (i--) {
c->mcl_next = sp->sl_head;
sp->sl_head = (void *)c++;
}
} else {
VERIFY(class == MC_BIGCL);
mbstat.m_bigclusters = m_total(MC_BIGCL);
mbstat.m_bigclfree = m_infree(MC_BIGCL) +
m_infree(MC_MBUF_BIGCL);
while (i--) {
mbc->mbc_next = sp->sl_head;
sp->sl_head = (void *)mbc++;
}
}
/* Insert into the mbuf or 2k or 4k slab list */
slab_insert(sp, class);
if ((i = mb_waiters) > 0) {
mb_waiters = 0;
}
if (i != 0) {
mbwdog_logger("waking up all threads");
wakeup(mb_waitchan);
}
}
return count != 0;
}
/*
* For each class, initialize the freelist to hold m_minlimit() objects.
*/
static void
freelist_init(mbuf_class_t class)
{
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
VERIFY(class == MC_CL || class == MC_BIGCL);
VERIFY(m_total(class) == 0);
VERIFY(m_minlimit(class) > 0);
while (m_total(class) < m_minlimit(class)) {
(void) freelist_populate(class, m_minlimit(class), M_WAIT);
}
VERIFY(m_total(class) >= m_minlimit(class));
}
/*
* (Inaccurately) check if it might be worth a trip back to the
* mcache layer due the availability of objects there. We'll
* end up back here if there's nothing up there.
*/
static boolean_t
mbuf_cached_above(mbuf_class_t class, int wait)
{
switch (class) {
case MC_MBUF:
if (wait & MCR_COMP) {
return !mcache_bkt_isempty(m_cache(MC_MBUF_CL)) ||
!mcache_bkt_isempty(m_cache(MC_MBUF_BIGCL));
}
break;
case MC_CL:
if (wait & MCR_COMP) {
return !mcache_bkt_isempty(m_cache(MC_MBUF_CL));
}
break;
case MC_BIGCL:
if (wait & MCR_COMP) {
return !mcache_bkt_isempty(m_cache(MC_MBUF_BIGCL));
}
break;
case MC_16KCL:
if (wait & MCR_COMP) {
return !mcache_bkt_isempty(m_cache(MC_MBUF_16KCL));
}
break;
case MC_MBUF_CL:
case MC_MBUF_BIGCL:
case MC_MBUF_16KCL:
break;
default:
VERIFY(0);
/* NOTREACHED */
}
return !mcache_bkt_isempty(m_cache(class));
}
/*
* If possible, convert constructed objects to raw ones.
*/
static boolean_t
mbuf_steal(mbuf_class_t class, unsigned int num)
{
mcache_obj_t *top = NULL;
mcache_obj_t **list = ⊤
unsigned int tot = 0;
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
switch (class) {
case MC_MBUF:
case MC_CL:
case MC_BIGCL:
case MC_16KCL:
return FALSE;
case MC_MBUF_CL:
case MC_MBUF_BIGCL:
case MC_MBUF_16KCL:
/* Get the required number of constructed objects if possible */
if (m_infree(class) > m_minlimit(class)) {
tot = cslab_alloc(class, &list,
MIN(num, m_infree(class)));
}
/* And destroy them to get back the raw objects */
if (top != NULL) {
(void) cslab_free(class, top, 1);
}
break;
default:
VERIFY(0);
/* NOTREACHED */
}
return tot == num;
}
static void
m_reclaim(mbuf_class_t class, unsigned int num, boolean_t comp)
{
int m, bmap = 0;
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
VERIFY(m_total(MC_CL) <= m_maxlimit(MC_CL));
VERIFY(m_total(MC_BIGCL) <= m_maxlimit(MC_BIGCL));
VERIFY(m_total(MC_16KCL) <= m_maxlimit(MC_16KCL));
/*
* This logic can be made smarter; for now, simply mark
* all other related classes as potential victims.
*/
switch (class) {
case MC_MBUF:
m_wantpurge(MC_CL)++;
m_wantpurge(MC_BIGCL)++;
m_wantpurge(MC_MBUF_CL)++;
m_wantpurge(MC_MBUF_BIGCL)++;
break;
case MC_CL:
m_wantpurge(MC_MBUF)++;
m_wantpurge(MC_BIGCL)++;
m_wantpurge(MC_MBUF_BIGCL)++;
if (!comp) {
m_wantpurge(MC_MBUF_CL)++;
}
break;
case MC_BIGCL:
m_wantpurge(MC_MBUF)++;
m_wantpurge(MC_CL)++;
m_wantpurge(MC_MBUF_CL)++;
if (!comp) {
m_wantpurge(MC_MBUF_BIGCL)++;
}
break;
case MC_16KCL:
if (!comp) {
m_wantpurge(MC_MBUF_16KCL)++;
}
break;
default:
VERIFY(0);
/* NOTREACHED */
}
/*
* Run through each marked class and check if we really need to
* purge (and therefore temporarily disable) the per-CPU caches
* layer used by the class. If so, remember the classes since
* we are going to drop the lock below prior to purging.
*/
for (m = 0; m < MC_MAX; m++) {
if (m_wantpurge(m) > 0) {
m_wantpurge(m) = 0;
/*
* Try hard to steal the required number of objects
* from the freelist of other mbuf classes. Only
* purge and disable the per-CPU caches layer when
* we don't have enough; it's the last resort.
*/
if (!mbuf_steal(m, num)) {
bmap |= (1 << m);
}
}
}
lck_mtx_unlock(mbuf_mlock);
if (bmap != 0) {
/* signal the domains to drain */
net_drain_domains();
/* Sigh; we have no other choices but to ask mcache to purge */
for (m = 0; m < MC_MAX; m++) {
if ((bmap & (1 << m)) &&
mcache_purge_cache(m_cache(m), TRUE)) {
lck_mtx_lock(mbuf_mlock);
m_purge_cnt(m)++;
mbstat.m_drain++;
lck_mtx_unlock(mbuf_mlock);
}
}
} else {
/*
* Request mcache to reap extra elements from all of its caches;
* note that all reaps are serialized and happen only at a fixed
* interval.
*/
mcache_reap();
}
lck_mtx_lock(mbuf_mlock);
}
struct mbuf *
m_get_common(int wait, short type, int hdr)
{
struct mbuf *m;
int mcflags = MSLEEPF(wait);
/* Is this due to a non-blocking retry? If so, then try harder */
if (mcflags & MCR_NOSLEEP) {
mcflags |= MCR_TRYHARD;
}
m = mcache_alloc(m_cache(MC_MBUF), mcflags);
if (m != NULL) {
mbuf_init(m, hdr, type);
mtype_stat_inc(type);
mtype_stat_dec(MT_FREE);
}
return m;
}
/*
* Space allocation routines; these are also available as macros
* for critical paths.
*/
#define _M_GETHDR(wait, type) m_get_common(wait, type, 1)
struct mbuf *
m_free(struct mbuf *m)
{
struct mbuf *n = m->m_next;
if (m->m_type == MT_FREE) {
panic("m_free: freeing an already freed mbuf");
}
if (m->m_flags & M_PKTHDR) {
/* Free the aux data and tags if there is any */
m_tag_delete_chain(m);
m_do_tx_compl_callback(m, NULL);
}
if (m->m_flags & M_EXT) {
if (MBUF_IS_PAIRED(m) && m_free_paired(m)) {
return n;
}
/*
* Make sure that we don't touch any ext_ref
* member after we decrement the reference count
* since that may lead to use-after-free
* when we do not hold the last reference.
*/
const bool composite = !!(MEXT_FLAGS(m) & EXTF_COMPOSITE);
const m_ext_free_func_t m_free_func = m_get_ext_free(m);
const uint16_t minref = MEXT_MINREF(m);
const uint16_t refcnt = m_decref(m);
if (refcnt == minref && !composite) {
if (m_free_func == NULL) {
mcache_free(m_cache(MC_CL), m->m_ext.ext_buf);
} else if (m_free_func == m_bigfree) {
mcache_free(m_cache(MC_BIGCL),
m->m_ext.ext_buf);
} else if (m_free_func == m_16kfree) {
mcache_free(m_cache(MC_16KCL),
m->m_ext.ext_buf);
} else {
(*m_free_func)(m->m_ext.ext_buf,
m->m_ext.ext_size, m_get_ext_arg(m));
}
mcache_free(ref_cache, m_get_rfa(m));
m_set_ext(m, NULL, NULL, NULL);
} else if (refcnt == minref && composite) {
VERIFY(!(MEXT_FLAGS(m) & EXTF_PAIRED));
mtype_stat_dec(m->m_type);
mtype_stat_inc(MT_FREE);
m->m_type = MT_FREE;
m->m_flags = M_EXT;
m->m_len = 0;
m->m_next = m->m_nextpkt = NULL;
/*
* MEXT_FLAGS is safe to access here
* since we are now sure that we held
* the last reference to ext_ref.
*/
MEXT_FLAGS(m) &= ~EXTF_READONLY;
/* "Free" into the intermediate cache */
if (m_free_func == NULL) {
mcache_free(m_cache(MC_MBUF_CL), m);
} else if (m_free_func == m_bigfree) {
mcache_free(m_cache(MC_MBUF_BIGCL), m);
} else {
VERIFY(m_free_func == m_16kfree);
mcache_free(m_cache(MC_MBUF_16KCL), m);
}
return n;
}
}
mtype_stat_dec(m->m_type);
mtype_stat_inc(MT_FREE);
m->m_type = MT_FREE;
m->m_flags = m->m_len = 0;
m->m_next = m->m_nextpkt = NULL;
mcache_free(m_cache(MC_MBUF), m);
return n;
}
__private_extern__ struct mbuf *
m_clattach(struct mbuf *m, int type, caddr_t extbuf,
void (*extfree)(caddr_t, u_int, caddr_t), size_t extsize, caddr_t extarg,
int wait, int pair)
{
struct ext_ref *rfa = NULL;
/*
* If pairing is requested and an existing mbuf is provided, reject
* it if it's already been paired to another cluster. Otherwise,
* allocate a new one or free any existing below.
*/
if ((m != NULL && MBUF_IS_PAIRED(m)) ||
(m == NULL && (m = _M_GETHDR(wait, type)) == NULL)) {
return NULL;
}
if (m->m_flags & M_EXT) {
/*
* Make sure that we don't touch any ext_ref
* member after we decrement the reference count
* since that may lead to use-after-free
* when we do not hold the last reference.
*/
const bool composite = !!(MEXT_FLAGS(m) & EXTF_COMPOSITE);
VERIFY(!(MEXT_FLAGS(m) & EXTF_PAIRED) && MEXT_PMBUF(m) == NULL);
const m_ext_free_func_t m_free_func = m_get_ext_free(m);
const uint16_t minref = MEXT_MINREF(m);
const uint16_t refcnt = m_decref(m);
if (refcnt == minref && !composite) {
if (m_free_func == NULL) {
mcache_free(m_cache(MC_CL), m->m_ext.ext_buf);
} else if (m_free_func == m_bigfree) {
mcache_free(m_cache(MC_BIGCL),
m->m_ext.ext_buf);
} else if (m_free_func == m_16kfree) {
mcache_free(m_cache(MC_16KCL),
m->m_ext.ext_buf);
} else {
(*m_free_func)(m->m_ext.ext_buf,
m->m_ext.ext_size, m_get_ext_arg(m));
}
/* Re-use the reference structure */
rfa = m_get_rfa(m);
} else if (refcnt == minref && composite) {
VERIFY(m->m_type != MT_FREE);
mtype_stat_dec(m->m_type);
mtype_stat_inc(MT_FREE);
m->m_type = MT_FREE;
m->m_flags = M_EXT;
m->m_len = 0;
m->m_next = m->m_nextpkt = NULL;
/*
* MEXT_FLAGS is safe to access here
* since we are now sure that we held
* the last reference to ext_ref.
*/
MEXT_FLAGS(m) &= ~EXTF_READONLY;
/* "Free" into the intermediate cache */
if (m_free_func == NULL) {
mcache_free(m_cache(MC_MBUF_CL), m);
} else if (m_free_func == m_bigfree) {
mcache_free(m_cache(MC_MBUF_BIGCL), m);
} else {
VERIFY(m_free_func == m_16kfree);
mcache_free(m_cache(MC_MBUF_16KCL), m);
}
/*
* Allocate a new mbuf, since we didn't divorce
* the composite mbuf + cluster pair above.
*/
if ((m = _M_GETHDR(wait, type)) == NULL) {
return NULL;
}
}
}
if (rfa == NULL &&
(rfa = mcache_alloc(ref_cache, MSLEEPF(wait))) == NULL) {
m_free(m);
return NULL;
}
if (!pair) {
mext_init(m, extbuf, extsize, extfree, extarg, rfa,
0, 1, 0, 0, 0, NULL);
} else {
mext_init(m, extbuf, extsize, extfree, (caddr_t)m, rfa,
1, 1, 1, EXTF_PAIRED, 0, m);
}
return m;
}
/*
* Perform `fast' allocation mbuf clusters from a cache of recently-freed
* clusters. (If the cache is empty, new clusters are allocated en-masse.)
*/
struct mbuf *
m_getcl(int wait, int type, int flags)
{
struct mbuf *m = NULL;
int hdr = (flags & M_PKTHDR);
int mcflags = MSLEEPF(wait);
/* Is this due to a non-blocking retry? If so, then try harder */
if (mcflags & MCR_NOSLEEP) {
mcflags |= MCR_TRYHARD;
}
m = mcache_alloc(m_cache(MC_MBUF_CL), mcflags);
if (m != NULL) {
u_int16_t flag;
struct ext_ref *rfa;
void *cl;
VERIFY(m->m_type == MT_FREE && m->m_flags == M_EXT);
cl = m->m_ext.ext_buf;
rfa = m_get_rfa(m);
ASSERT(cl != NULL && rfa != NULL);
VERIFY(MBUF_IS_COMPOSITE(m) && m_get_ext_free(m) == NULL);
flag = MEXT_FLAGS(m);
mbuf_init(m, hdr, type);
MBUF_CL_INIT(m, cl, rfa, 1, flag);
mtype_stat_inc(type);
mtype_stat_dec(MT_FREE);
}
return m;
}
/* m_mclget() add an mbuf cluster to a normal mbuf */
struct mbuf *
m_mclget(struct mbuf *m, int wait)
{
struct ext_ref *rfa = NULL;
if ((rfa = mcache_alloc(ref_cache, MSLEEPF(wait))) == NULL) {
return m;
}
m->m_ext.ext_buf = m_mclalloc(wait);
if (m->m_ext.ext_buf != NULL) {
MBUF_CL_INIT(m, m->m_ext.ext_buf, rfa, 1, 0);
} else {
mcache_free(ref_cache, rfa);
}
return m;
}
/* Allocate an mbuf cluster */
caddr_t
m_mclalloc(int wait)
{
int mcflags = MSLEEPF(wait);
/* Is this due to a non-blocking retry? If so, then try harder */
if (mcflags & MCR_NOSLEEP) {
mcflags |= MCR_TRYHARD;
}
return mcache_alloc(m_cache(MC_CL), mcflags);
}
/* Free an mbuf cluster */
void
m_mclfree(caddr_t p)
{
mcache_free(m_cache(MC_CL), p);
}
__private_extern__ caddr_t
m_bigalloc(int wait)
{
int mcflags = MSLEEPF(wait);
/* Is this due to a non-blocking retry? If so, then try harder */
if (mcflags & MCR_NOSLEEP) {
mcflags |= MCR_TRYHARD;
}
return mcache_alloc(m_cache(MC_BIGCL), mcflags);
}
__private_extern__ void
m_bigfree(caddr_t p, __unused u_int size, __unused caddr_t arg)
{
mcache_free(m_cache(MC_BIGCL), p);
}
/* m_mbigget() add an 4KB mbuf cluster to a normal mbuf */
__private_extern__ struct mbuf *
m_mbigget(struct mbuf *m, int wait)
{
struct ext_ref *rfa = NULL;
if ((rfa = mcache_alloc(ref_cache, MSLEEPF(wait))) == NULL) {
return m;
}
m->m_ext.ext_buf = m_bigalloc(wait);
if (m->m_ext.ext_buf != NULL) {
MBUF_BIGCL_INIT(m, m->m_ext.ext_buf, rfa, 1, 0);
} else {
mcache_free(ref_cache, rfa);
}
return m;
}
__private_extern__ caddr_t
m_16kalloc(int wait)
{
int mcflags = MSLEEPF(wait);
/* Is this due to a non-blocking retry? If so, then try harder */
if (mcflags & MCR_NOSLEEP) {
mcflags |= MCR_TRYHARD;
}
return mcache_alloc(m_cache(MC_16KCL), mcflags);
}
__private_extern__ void
m_16kfree(caddr_t p, __unused u_int size, __unused caddr_t arg)
{
mcache_free(m_cache(MC_16KCL), p);
}
/* m_m16kget() add a 16KB mbuf cluster to a normal mbuf */
__private_extern__ struct mbuf *
m_m16kget(struct mbuf *m, int wait)
{
struct ext_ref *rfa = NULL;
if ((rfa = mcache_alloc(ref_cache, MSLEEPF(wait))) == NULL) {
return m;
}
m->m_ext.ext_buf = m_16kalloc(wait);
if (m->m_ext.ext_buf != NULL) {
MBUF_16KCL_INIT(m, m->m_ext.ext_buf, rfa, 1, 0);
} else {
mcache_free(ref_cache, rfa);
}
return m;
}
/*
* Return a list of mbuf hdrs that point to clusters. Try for num_needed;
* if wantall is not set, return whatever number were available. Set up the
* first num_with_pkthdrs with mbuf hdrs configured as packet headers; these
* are chained on the m_nextpkt field. Any packets requested beyond this
* are chained onto the last packet header's m_next field. The size of
* the cluster is controlled by the parameter bufsize.
*/
__private_extern__ struct mbuf *
m_getpackets_internal(unsigned int *num_needed, int num_with_pkthdrs,
int wait, int wantall, size_t bufsize)
{
struct mbuf *m = NULL;
struct mbuf **np, *top;
unsigned int pnum, needed = *num_needed;
mcache_obj_t *mp_list = NULL;
int mcflags = MSLEEPF(wait);
mcache_t *cp;
u_int16_t flag;
struct ext_ref *rfa;
void *cl;
ASSERT(bufsize == m_maxsize(MC_CL) ||
bufsize == m_maxsize(MC_BIGCL) ||
bufsize == m_maxsize(MC_16KCL));
top = NULL;
np = ⊤
pnum = 0;
/*
* The caller doesn't want all the requested buffers; only some.
* Try hard to get what we can, but don't block. This effectively
* overrides MCR_SLEEP, since this thread will not go to sleep
* if we can't get all the buffers.
*/
if (!wantall || (mcflags & MCR_NOSLEEP)) {
mcflags |= MCR_TRYHARD;
}
/* Allocate the composite mbuf + cluster elements from the cache */
if (bufsize == m_maxsize(MC_CL)) {
cp = m_cache(MC_MBUF_CL);
} else if (bufsize == m_maxsize(MC_BIGCL)) {
cp = m_cache(MC_MBUF_BIGCL);
} else {
cp = m_cache(MC_MBUF_16KCL);
}
needed = mcache_alloc_ext(cp, &mp_list, needed, mcflags);
for (pnum = 0; pnum < needed; pnum++) {
m = (struct mbuf *)mp_list;
mp_list = mp_list->obj_next;
VERIFY(m->m_type == MT_FREE && m->m_flags == M_EXT);
cl = m->m_ext.ext_buf;
rfa = m_get_rfa(m);
ASSERT(cl != NULL && rfa != NULL);
VERIFY(MBUF_IS_COMPOSITE(m));
flag = MEXT_FLAGS(m);
mbuf_init(m, num_with_pkthdrs, MT_DATA);
if (bufsize == m_maxsize(MC_16KCL)) {
MBUF_16KCL_INIT(m, cl, rfa, 1, flag);
} else if (bufsize == m_maxsize(MC_BIGCL)) {
MBUF_BIGCL_INIT(m, cl, rfa, 1, flag);
} else {
MBUF_CL_INIT(m, cl, rfa, 1, flag);
}
if (num_with_pkthdrs > 0) {
--num_with_pkthdrs;
}
*np = m;
if (num_with_pkthdrs > 0) {
np = &m->m_nextpkt;
} else {
np = &m->m_next;
}
}
ASSERT(pnum != *num_needed || mp_list == NULL);
if (mp_list != NULL) {
mcache_free_ext(cp, mp_list);
}
if (pnum > 0) {
mtype_stat_add(MT_DATA, pnum);
mtype_stat_sub(MT_FREE, pnum);
}
if (wantall && (pnum != *num_needed)) {
if (top != NULL) {
m_freem_list(top);
}
return NULL;
}
if (pnum > *num_needed) {
printf("%s: File a radar related to <rdar://10146739>. \
needed = %u, pnum = %u, num_needed = %u \n",
__func__, needed, pnum, *num_needed);
}
*num_needed = pnum;
return top;
}
/*
* Return list of mbuf linked by m_nextpkt. Try for numlist, and if
* wantall is not set, return whatever number were available. The size of
* each mbuf in the list is controlled by the parameter packetlen. Each
* mbuf of the list may have a chain of mbufs linked by m_next. Each mbuf
* in the chain is called a segment. If maxsegments is not null and the
* value pointed to is not null, this specify the maximum number of segments
* for a chain of mbufs. If maxsegments is zero or the value pointed to
* is zero the caller does not have any restriction on the number of segments.
* The actual number of segments of a mbuf chain is return in the value
* pointed to by maxsegments.
*/
__private_extern__ struct mbuf *
m_allocpacket_internal(unsigned int *numlist, size_t packetlen,
unsigned int *maxsegments, int wait, int wantall, size_t wantsize)
{
struct mbuf **np, *top, *first = NULL;
size_t bufsize, r_bufsize;
unsigned int num = 0;
unsigned int nsegs = 0;
unsigned int needed = 0, resid;
int mcflags = MSLEEPF(wait);
mcache_obj_t *mp_list = NULL, *rmp_list = NULL;
mcache_t *cp = NULL, *rcp = NULL;
if (*numlist == 0) {
os_log(OS_LOG_DEFAULT, "m_allocpacket_internal *numlist is 0");
return NULL;
}
top = NULL;
np = ⊤
if (wantsize == 0) {
if (packetlen <= MINCLSIZE) {
bufsize = packetlen;
} else if (packetlen > m_maxsize(MC_CL)) {
/* Use 4KB if jumbo cluster pool isn't available */
if (packetlen <= m_maxsize(MC_BIGCL)) {
bufsize = m_maxsize(MC_BIGCL);
} else {
bufsize = m_maxsize(MC_16KCL);
}
} else {
bufsize = m_maxsize(MC_CL);
}
} else if (wantsize == m_maxsize(MC_CL) ||
wantsize == m_maxsize(MC_BIGCL) ||
wantsize == m_maxsize(MC_16KCL)) {
bufsize = wantsize;
} else {
*numlist = 0;
os_log(OS_LOG_DEFAULT, "m_allocpacket_internal wantsize unsupported");
return NULL;
}
if (bufsize <= MHLEN) {
nsegs = 1;
} else if (bufsize <= MINCLSIZE) {
if (maxsegments != NULL && *maxsegments == 1) {
bufsize = m_maxsize(MC_CL);
nsegs = 1;
} else {
nsegs = 2;
}
} else if (bufsize == m_maxsize(MC_16KCL)) {
nsegs = ((packetlen - 1) >> M16KCLSHIFT) + 1;
} else if (bufsize == m_maxsize(MC_BIGCL)) {
nsegs = ((packetlen - 1) >> MBIGCLSHIFT) + 1;
} else {
nsegs = ((packetlen - 1) >> MCLSHIFT) + 1;
}
if (maxsegments != NULL) {
if (*maxsegments && nsegs > *maxsegments) {
*maxsegments = nsegs;
*numlist = 0;
os_log(OS_LOG_DEFAULT, "m_allocpacket_internal nsegs > *maxsegments");
return NULL;
}
*maxsegments = nsegs;
}
/*
* The caller doesn't want all the requested buffers; only some.
* Try hard to get what we can, but don't block. This effectively
* overrides MCR_SLEEP, since this thread will not go to sleep
* if we can't get all the buffers.
*/
if (!wantall || (mcflags & MCR_NOSLEEP)) {
mcflags |= MCR_TRYHARD;
}
/*
* Simple case where all elements in the lists/chains are mbufs.
* Unless bufsize is greater than MHLEN, each segment chain is made
* up of exactly 1 mbuf. Otherwise, each segment chain is made up
* of 2 mbufs; the second one is used for the residual data, i.e.
* the remaining data that cannot fit into the first mbuf.
*/
if (bufsize <= MINCLSIZE) {
/* Allocate the elements in one shot from the mbuf cache */
ASSERT(bufsize <= MHLEN || nsegs == 2);
cp = m_cache(MC_MBUF);
needed = mcache_alloc_ext(cp, &mp_list,
(*numlist) * nsegs, mcflags);
/*
* The number of elements must be even if we are to use an
* mbuf (instead of a cluster) to store the residual data.
* If we couldn't allocate the requested number of mbufs,
* trim the number down (if it's odd) in order to avoid
* creating a partial segment chain.
*/
if (bufsize > MHLEN && (needed & 0x1)) {
needed--;
}
while (num < needed) {
struct mbuf *m = NULL;
m = (struct mbuf *)mp_list;
mp_list = mp_list->obj_next;
ASSERT(m != NULL);
mbuf_init(m, 1, MT_DATA);
num++;
if (bufsize > MHLEN) {
/* A second mbuf for this segment chain */
m->m_next = (struct mbuf *)mp_list;
mp_list = mp_list->obj_next;
ASSERT(m->m_next != NULL);
mbuf_init(m->m_next, 0, MT_DATA);
num++;
}
*np = m;
np = &m->m_nextpkt;
}
ASSERT(num != *numlist || mp_list == NULL);
if (num > 0) {
mtype_stat_add(MT_DATA, num);
mtype_stat_sub(MT_FREE, num);
}
num /= nsegs;
/* We've got them all; return to caller */
if (num == *numlist) {
return top;
}
goto fail;
}
/*
* Complex cases where elements are made up of one or more composite
* mbufs + cluster, depending on packetlen. Each N-segment chain can
* be illustrated as follows:
*
* [mbuf + cluster 1] [mbuf + cluster 2] ... [mbuf + cluster N]
*
* Every composite mbuf + cluster element comes from the intermediate
* cache (either MC_MBUF_CL or MC_MBUF_BIGCL). For space efficiency,
* the last composite element will come from the MC_MBUF_CL cache,
* unless the residual data is larger than 2KB where we use the
* big cluster composite cache (MC_MBUF_BIGCL) instead. Residual
* data is defined as extra data beyond the first element that cannot
* fit into the previous element, i.e. there is no residual data if
* the chain only has 1 segment.
*/
r_bufsize = bufsize;
resid = packetlen > bufsize ? packetlen % bufsize : 0;
if (resid > 0) {
/* There is residual data; figure out the cluster size */
if (wantsize == 0 && packetlen > MINCLSIZE) {
/*
* Caller didn't request that all of the segments
* in the chain use the same cluster size; use the
* smaller of the cluster sizes.
*/
if (resid > m_maxsize(MC_BIGCL)) {
r_bufsize = m_maxsize(MC_16KCL);
} else if (resid > m_maxsize(MC_CL)) {
r_bufsize = m_maxsize(MC_BIGCL);
} else {
r_bufsize = m_maxsize(MC_CL);
}
} else {
/* Use the same cluster size as the other segments */
resid = 0;
}
}
needed = *numlist;
if (resid > 0) {
/*
* Attempt to allocate composite mbuf + cluster elements for
* the residual data in each chain; record the number of such
* elements that can be allocated so that we know how many
* segment chains we can afford to create.
*/
if (r_bufsize <= m_maxsize(MC_CL)) {
rcp = m_cache(MC_MBUF_CL);
} else if (r_bufsize <= m_maxsize(MC_BIGCL)) {
rcp = m_cache(MC_MBUF_BIGCL);
} else {
rcp = m_cache(MC_MBUF_16KCL);
}
needed = mcache_alloc_ext(rcp, &rmp_list, *numlist, mcflags);
if (needed == 0) {
goto fail;
}
/* This is temporarily reduced for calculation */
ASSERT(nsegs > 1);
nsegs--;
}
/*
* Attempt to allocate the rest of the composite mbuf + cluster
* elements for the number of segment chains that we need.
*/
if (bufsize <= m_maxsize(MC_CL)) {
cp = m_cache(MC_MBUF_CL);
} else if (bufsize <= m_maxsize(MC_BIGCL)) {
cp = m_cache(MC_MBUF_BIGCL);
} else {
cp = m_cache(MC_MBUF_16KCL);
}
needed = mcache_alloc_ext(cp, &mp_list, needed * nsegs, mcflags);
/* Round it down to avoid creating a partial segment chain */
needed = (needed / nsegs) * nsegs;
if (needed == 0) {
goto fail;
}
if (resid > 0) {
/*
* We're about to construct the chain(s); take into account
* the number of segments we have created above to hold the
* residual data for each chain, as well as restore the
* original count of segments per chain.
*/
ASSERT(nsegs > 0);
needed += needed / nsegs;
nsegs++;
}
for (;;) {
struct mbuf *m = NULL;
u_int16_t flag;
struct ext_ref *rfa;
void *cl;
int pkthdr;
m_ext_free_func_t m_free_func;
++num;
if (nsegs == 1 || (num % nsegs) != 0 || resid == 0) {
m = (struct mbuf *)mp_list;
mp_list = mp_list->obj_next;
} else {
m = (struct mbuf *)rmp_list;
rmp_list = rmp_list->obj_next;
}
m_free_func = m_get_ext_free(m);
ASSERT(m != NULL);
VERIFY(m->m_type == MT_FREE && m->m_flags == M_EXT);
VERIFY(m_free_func == NULL || m_free_func == m_bigfree ||
m_free_func == m_16kfree);
cl = m->m_ext.ext_buf;
rfa = m_get_rfa(m);
ASSERT(cl != NULL && rfa != NULL);
VERIFY(MBUF_IS_COMPOSITE(m));
flag = MEXT_FLAGS(m);
pkthdr = (nsegs == 1 || (num % nsegs) == 1);
if (pkthdr) {
first = m;
}
mbuf_init(m, pkthdr, MT_DATA);
if (m_free_func == m_16kfree) {
MBUF_16KCL_INIT(m, cl, rfa, 1, flag);
} else if (m_free_func == m_bigfree) {
MBUF_BIGCL_INIT(m, cl, rfa, 1, flag);
} else {
MBUF_CL_INIT(m, cl, rfa, 1, flag);
}
*np = m;
if ((num % nsegs) == 0) {
np = &first->m_nextpkt;
} else {
np = &m->m_next;
}
if (num == needed) {
break;
}
}
if (num > 0) {
mtype_stat_add(MT_DATA, num);
mtype_stat_sub(MT_FREE, num);
}
num /= nsegs;
/* We've got them all; return to caller */
if (num == *numlist) {
ASSERT(mp_list == NULL && rmp_list == NULL);
return top;
}
fail:
/* Free up what's left of the above */
if (mp_list != NULL) {
mcache_free_ext(cp, mp_list);
}
if (rmp_list != NULL) {
mcache_free_ext(rcp, rmp_list);
}
if (wantall && top != NULL) {
m_freem_list(top);
*numlist = 0;
return NULL;
}
*numlist = num;
return top;
}
/*
* Free an mbuf list (m_nextpkt) while following m_next. Returns the count
* for mbufs packets freed. Used by the drivers.
*/
int
m_freem_list(struct mbuf *m)
{
struct mbuf *nextpkt;
mcache_obj_t *mp_list = NULL;
mcache_obj_t *mcl_list = NULL;
mcache_obj_t *mbc_list = NULL;
mcache_obj_t *m16k_list = NULL;
mcache_obj_t *m_mcl_list = NULL;
mcache_obj_t *m_mbc_list = NULL;
mcache_obj_t *m_m16k_list = NULL;
mcache_obj_t *ref_list = NULL;
int pktcount = 0;
int mt_free = 0, mt_data = 0, mt_header = 0, mt_soname = 0, mt_tag = 0;
while (m != NULL) {
pktcount++;
nextpkt = m->m_nextpkt;
m->m_nextpkt = NULL;
while (m != NULL) {
struct mbuf *next = m->m_next;
mcache_obj_t *o, *rfa;
if (m->m_type == MT_FREE) {
panic("m_free: freeing an already freed mbuf");
}
if (m->m_flags & M_PKTHDR) {
/* Free the aux data and tags if there is any */
m_tag_delete_chain(m);
m_do_tx_compl_callback(m, NULL);
}
if (!(m->m_flags & M_EXT)) {
mt_free++;
goto simple_free;
}
if (MBUF_IS_PAIRED(m) && m_free_paired(m)) {
m = next;
continue;
}
mt_free++;
o = (mcache_obj_t *)(void *)m->m_ext.ext_buf;
/*
* Make sure that we don't touch any ext_ref
* member after we decrement the reference count
* since that may lead to use-after-free
* when we do not hold the last reference.
*/
const bool composite = !!(MEXT_FLAGS(m) & EXTF_COMPOSITE);
const m_ext_free_func_t m_free_func = m_get_ext_free(m);
const uint16_t minref = MEXT_MINREF(m);
const uint16_t refcnt = m_decref(m);
if (refcnt == minref && !composite) {
if (m_free_func == NULL) {
o->obj_next = mcl_list;
mcl_list = o;
} else if (m_free_func == m_bigfree) {
o->obj_next = mbc_list;
mbc_list = o;
} else if (m_free_func == m_16kfree) {
o->obj_next = m16k_list;
m16k_list = o;
} else {
(*(m_free_func))((caddr_t)o,
m->m_ext.ext_size,
m_get_ext_arg(m));
}
rfa = (mcache_obj_t *)(void *)m_get_rfa(m);
rfa->obj_next = ref_list;
ref_list = rfa;
m_set_ext(m, NULL, NULL, NULL);
} else if (refcnt == minref && composite) {
VERIFY(!(MEXT_FLAGS(m) & EXTF_PAIRED));
/*
* Amortize the costs of atomic operations
* by doing them at the end, if possible.
*/
if (m->m_type == MT_DATA) {
mt_data++;
} else if (m->m_type == MT_HEADER) {
mt_header++;
} else if (m->m_type == MT_SONAME) {
mt_soname++;
} else if (m->m_type == MT_TAG) {
mt_tag++;
} else {
mtype_stat_dec(m->m_type);
}
m->m_type = MT_FREE;
m->m_flags = M_EXT;
m->m_len = 0;
m->m_next = m->m_nextpkt = NULL;
/*
* MEXT_FLAGS is safe to access here
* since we are now sure that we held
* the last reference to ext_ref.
*/
MEXT_FLAGS(m) &= ~EXTF_READONLY;
/* "Free" into the intermediate cache */
o = (mcache_obj_t *)m;
if (m_free_func == NULL) {
o->obj_next = m_mcl_list;
m_mcl_list = o;
} else if (m_free_func == m_bigfree) {
o->obj_next = m_mbc_list;
m_mbc_list = o;
} else {
VERIFY(m_free_func == m_16kfree);
o->obj_next = m_m16k_list;
m_m16k_list = o;
}
m = next;
continue;
}
simple_free:
/*
* Amortize the costs of atomic operations
* by doing them at the end, if possible.
*/
if (m->m_type == MT_DATA) {
mt_data++;
} else if (m->m_type == MT_HEADER) {
mt_header++;
} else if (m->m_type == MT_SONAME) {
mt_soname++;
} else if (m->m_type == MT_TAG) {
mt_tag++;
} else if (m->m_type != MT_FREE) {
mtype_stat_dec(m->m_type);
}
m->m_type = MT_FREE;
m->m_flags = m->m_len = 0;
m->m_next = m->m_nextpkt = NULL;
((mcache_obj_t *)m)->obj_next = mp_list;
mp_list = (mcache_obj_t *)m;
m = next;
}
m = nextpkt;
}
if (mt_free > 0) {
mtype_stat_add(MT_FREE, mt_free);
}
if (mt_data > 0) {
mtype_stat_sub(MT_DATA, mt_data);
}
if (mt_header > 0) {
mtype_stat_sub(MT_HEADER, mt_header);
}
if (mt_soname > 0) {
mtype_stat_sub(MT_SONAME, mt_soname);
}
if (mt_tag > 0) {
mtype_stat_sub(MT_TAG, mt_tag);
}
if (mp_list != NULL) {
mcache_free_ext(m_cache(MC_MBUF), mp_list);
}
if (mcl_list != NULL) {
mcache_free_ext(m_cache(MC_CL), mcl_list);
}
if (mbc_list != NULL) {
mcache_free_ext(m_cache(MC_BIGCL), mbc_list);
}
if (m16k_list != NULL) {
mcache_free_ext(m_cache(MC_16KCL), m16k_list);
}
if (m_mcl_list != NULL) {
mcache_free_ext(m_cache(MC_MBUF_CL), m_mcl_list);
}
if (m_mbc_list != NULL) {
mcache_free_ext(m_cache(MC_MBUF_BIGCL), m_mbc_list);
}
if (m_m16k_list != NULL) {
mcache_free_ext(m_cache(MC_MBUF_16KCL), m_m16k_list);
}
if (ref_list != NULL) {
mcache_free_ext(ref_cache, ref_list);
}
return pktcount;
}
/*
* Equivalent to m_copym except that all necessary mbuf hdrs are allocated
* within this routine also.
*
* The last mbuf and offset accessed are passed in and adjusted on return to
* avoid having to iterate over the entire mbuf chain each time.
*/
struct mbuf *
m_copym_with_hdrs(struct mbuf *m0, int off0, int len0, int wait,
struct mbuf **m_lastm, int *m_off, uint32_t mode)
{
struct mbuf *m = m0, *n, **np = NULL;
int off = off0, len = len0;
struct mbuf *top = NULL;
int mcflags = MSLEEPF(wait);
mcache_obj_t *list = NULL;
int copyhdr = 0;
int type = 0;
int needed = 0;
if (off == 0 && (m->m_flags & M_PKTHDR)) {
copyhdr = 1;
}
if (m_lastm != NULL && *m_lastm != NULL) {
if (off0 >= *m_off) {
m = *m_lastm;
off = off0 - *m_off;
}
}
while (off >= m->m_len) {
off -= m->m_len;
m = m->m_next;
}
n = m;
while (len > 0) {
needed++;
len -= MIN(len, (n->m_len - ((needed == 1) ? off : 0)));
n = n->m_next;
}
needed++;
len = len0;
/*
* If the caller doesn't want to be put to sleep, mark it with
* MCR_TRYHARD so that we may reclaim buffers from other places
* before giving up.
*/
if (mcflags & MCR_NOSLEEP) {
mcflags |= MCR_TRYHARD;
}
if (mcache_alloc_ext(m_cache(MC_MBUF), &list, needed,
mcflags) != needed) {
goto nospace;
}
needed = 0;
while (len > 0) {
n = (struct mbuf *)list;
list = list->obj_next;
ASSERT(n != NULL && m != NULL);
type = (top == NULL) ? MT_HEADER : m->m_type;
mbuf_init(n, (top == NULL), type);
if (top == NULL) {
top = n;
np = &top->m_next;
continue;
} else {
needed++;
*np = n;
}
if (copyhdr) {
if ((mode == M_COPYM_MOVE_HDR) ||
(mode == M_COPYM_MUST_MOVE_HDR)) {
M_COPY_PKTHDR(n, m);
} else if ((mode == M_COPYM_COPY_HDR) ||
(mode == M_COPYM_MUST_COPY_HDR)) {
if (m_dup_pkthdr(n, m, wait) == 0) {
goto nospace;
}
}
n->m_pkthdr.len = len;
copyhdr = 0;
}
n->m_len = MIN(len, (m->m_len - off));
if (m->m_flags & M_EXT) {
n->m_ext = m->m_ext;
m_incref(m);
n->m_data = m->m_data + off;
n->m_flags |= M_EXT;
} else {
if (m_mtod_end(n) > m_mtod_upper_bound(n)) {
panic("%s n %p copy overflow",
__func__, n);
}
bcopy(mtod(m, caddr_t) + off, mtod(n, caddr_t),
(unsigned)n->m_len);
}
len -= n->m_len;
if (len == 0) {
if (m_lastm != NULL) {
*m_lastm = m;
*m_off = off0 + len0 - (off + n->m_len);
}
break;
}
off = 0;
m = m->m_next;
np = &n->m_next;
}
mtype_stat_inc(MT_HEADER);
mtype_stat_add(type, needed);
mtype_stat_sub(MT_FREE, needed + 1);
ASSERT(list == NULL);
return top;
nospace:
if (list != NULL) {
mcache_free_ext(m_cache(MC_MBUF), list);
}
if (top != NULL) {
m_freem(top);
}
return NULL;
}
#ifndef MBUF_GROWTH_NORMAL_THRESH
#define MBUF_GROWTH_NORMAL_THRESH 25
#endif
/*
* Cluster freelist allocation check.
*/
static int
m_howmany(int num, size_t bufsize)
{
int i = 0, j = 0;
u_int32_t m_mbclusters, m_clusters, m_bigclusters, m_16kclusters;
u_int32_t m_mbfree, m_clfree, m_bigclfree, m_16kclfree;
u_int32_t sumclusters, freeclusters;
u_int32_t percent_pool, percent_kmem;
u_int32_t mb_growth, mb_growth_thresh;
VERIFY(bufsize == m_maxsize(MC_BIGCL) ||
bufsize == m_maxsize(MC_16KCL));
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
/* Numbers in 2K cluster units */
m_mbclusters = m_total(MC_MBUF) >> NMBPCLSHIFT;
m_clusters = m_total(MC_CL);
m_bigclusters = m_total(MC_BIGCL) << NCLPBGSHIFT;
m_16kclusters = m_total(MC_16KCL);
sumclusters = m_mbclusters + m_clusters + m_bigclusters;
m_mbfree = m_infree(MC_MBUF) >> NMBPCLSHIFT;
m_clfree = m_infree(MC_CL);
m_bigclfree = m_infree(MC_BIGCL) << NCLPBGSHIFT;
m_16kclfree = m_infree(MC_16KCL);
freeclusters = m_mbfree + m_clfree + m_bigclfree;
/* Bail if we've maxed out the mbuf memory map */
if ((bufsize == m_maxsize(MC_BIGCL) && sumclusters >= nclusters) ||
(bufsize == m_maxsize(MC_16KCL) &&
(m_16kclusters << NCLPJCLSHIFT) >= njcl)) {
mbwdog_logger("maxed out nclusters (%u >= %u) or njcl (%u >= %u)",
sumclusters, nclusters,
(m_16kclusters << NCLPJCLSHIFT), njcl);
return 0;
}
if (bufsize == m_maxsize(MC_BIGCL)) {
/* Under minimum */
if (m_bigclusters < m_minlimit(MC_BIGCL)) {
return m_minlimit(MC_BIGCL) - m_bigclusters;
}
percent_pool =
((sumclusters - freeclusters) * 100) / sumclusters;
percent_kmem = (sumclusters * 100) / nclusters;
/*
* If a light/normal user, grow conservatively (75%)
* If a heavy user, grow aggressively (50%)
*/
if (percent_kmem < MBUF_GROWTH_NORMAL_THRESH) {
mb_growth = MB_GROWTH_NORMAL;
} else {
mb_growth = MB_GROWTH_AGGRESSIVE;
}
if (percent_kmem < 5) {
/* For initial allocations */
i = num;
} else {
/* Return if >= MBIGCL_LOWAT clusters available */
if (m_infree(MC_BIGCL) >= MBIGCL_LOWAT &&
m_total(MC_BIGCL) >=
MBIGCL_LOWAT + m_minlimit(MC_BIGCL)) {
return 0;
}
/* Ensure at least num clusters are accessible */
if (num >= m_infree(MC_BIGCL)) {
i = num - m_infree(MC_BIGCL);
}
if (num > m_total(MC_BIGCL) - m_minlimit(MC_BIGCL)) {
j = num - (m_total(MC_BIGCL) -
m_minlimit(MC_BIGCL));
}
i = MAX(i, j);
/*
* Grow pool if percent_pool > 75 (normal growth)
* or percent_pool > 50 (aggressive growth).
*/
mb_growth_thresh = 100 - (100 / (1 << mb_growth));
if (percent_pool > mb_growth_thresh) {
j = ((sumclusters + num) >> mb_growth) -
freeclusters;
}
i = MAX(i, j);
}
/* Check to ensure we didn't go over limits */
if (i + m_bigclusters >= m_maxlimit(MC_BIGCL)) {
i = m_maxlimit(MC_BIGCL) - m_bigclusters;
}
if ((i << 1) + sumclusters >= nclusters) {
i = (nclusters - sumclusters) >> 1;
}
VERIFY((m_total(MC_BIGCL) + i) <= m_maxlimit(MC_BIGCL));
VERIFY(sumclusters + (i << 1) <= nclusters);
} else { /* 16K CL */
/* Ensure at least num clusters are available */
if (num >= m_16kclfree) {
i = num - m_16kclfree;
}
/* Always grow 16KCL pool aggressively */
if (((m_16kclusters + num) >> 1) > m_16kclfree) {
j = ((m_16kclusters + num) >> 1) - m_16kclfree;
}
i = MAX(i, j);
/* Check to ensure we don't go over limit */
if ((i + m_total(MC_16KCL)) >= m_maxlimit(MC_16KCL)) {
i = m_maxlimit(MC_16KCL) - m_total(MC_16KCL);
}
}
return i;
}
uint64_t
mcl_to_paddr(char *addr)
{
vm_offset_t base_phys;
if (!MBUF_IN_MAP(addr)) {
return 0;
}
base_phys = mcl_paddr[atop_64(addr - (char *)mbutl)];
if (base_phys == 0) {
return 0;
}
return (uint64_t)(ptoa_64(base_phys) | ((uint64_t)addr & PAGE_MASK));
}
/*
* Inform the corresponding mcache(s) that there's a waiter below.
*/
static void
mbuf_waiter_inc(mbuf_class_t class, boolean_t comp)
{
mcache_waiter_inc(m_cache(class));
if (comp) {
if (class == MC_CL) {
mcache_waiter_inc(m_cache(MC_MBUF_CL));
} else if (class == MC_BIGCL) {
mcache_waiter_inc(m_cache(MC_MBUF_BIGCL));
} else if (class == MC_16KCL) {
mcache_waiter_inc(m_cache(MC_MBUF_16KCL));
} else {
mcache_waiter_inc(m_cache(MC_MBUF_CL));
mcache_waiter_inc(m_cache(MC_MBUF_BIGCL));
}
}
}
/*
* Inform the corresponding mcache(s) that there's no more waiter below.
*/
static void
mbuf_waiter_dec(mbuf_class_t class, boolean_t comp)
{
mcache_waiter_dec(m_cache(class));
if (comp) {
if (class == MC_CL) {
mcache_waiter_dec(m_cache(MC_MBUF_CL));
} else if (class == MC_BIGCL) {
mcache_waiter_dec(m_cache(MC_MBUF_BIGCL));
} else if (class == MC_16KCL) {
mcache_waiter_dec(m_cache(MC_MBUF_16KCL));
} else {
mcache_waiter_dec(m_cache(MC_MBUF_CL));
mcache_waiter_dec(m_cache(MC_MBUF_BIGCL));
}
}
}
static bool mbuf_watchdog_defunct_active = false;
struct mbuf_watchdog_defunct_args {
struct proc *top_app;
uint32_t top_app_space_used;
bool non_blocking;
};
extern const char *proc_name_address(void *p);
static void
mbuf_watchdog_defunct(thread_call_param_t arg0, thread_call_param_t arg1)
{
#pragma unused(arg0, arg1)
struct mbuf_watchdog_defunct_args args = {};
struct fileproc *fp = NULL;
args.non_blocking = false;
proc_iterate(PROC_ALLPROCLIST,
mbuf_watchdog_defunct_iterate, &args, NULL, NULL);
/*
* Defunct all sockets from this app.
*/
if (args.top_app != NULL) {
/* Restart the watchdog count. */
lck_mtx_lock(mbuf_mlock);
microuptime(&mb_wdtstart);
lck_mtx_unlock(mbuf_mlock);
os_log(OS_LOG_DEFAULT, "%s: defuncting all sockets from %s.%d",
__func__,
proc_name_address(args.top_app),
proc_pid(args.top_app));
proc_fdlock(args.top_app);
fdt_foreach(fp, args.top_app) {
struct fileglob *fg = fp->fp_glob;
struct socket *so = NULL;
if (FILEGLOB_DTYPE(fg) != DTYPE_SOCKET) {
continue;
}
so = (struct socket *)fp_get_data(fp);
if (!socket_try_lock(so)) {
continue;
}
if (sosetdefunct(args.top_app, so,
SHUTDOWN_SOCKET_LEVEL_DISCONNECT_ALL,
TRUE) == 0) {
sodefunct(args.top_app, so,
SHUTDOWN_SOCKET_LEVEL_DISCONNECT_ALL);
}
socket_unlock(so, 0);
}
proc_fdunlock(args.top_app);
proc_rele(args.top_app);
mbstat.m_forcedefunct++;
}
mbuf_watchdog_defunct_active = false;
}
/*
* Called during slab (blocking and non-blocking) allocation. If there
* is at least one waiter, and the time since the first waiter is blocked
* is greater than the watchdog timeout, panic the system.
*/
static void
mbuf_watchdog(void)
{
struct timeval now;
unsigned int since;
static thread_call_t defunct_tcall = NULL;
if (mb_waiters == 0 || !mb_watchdog) {
return;
}
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
microuptime(&now);
since = now.tv_sec - mb_wdtstart.tv_sec;
if (mbuf_watchdog_defunct_active) {
/*
* Don't panic the system while we are trying
* to find sockets to defunct.
*/
return;
}
if (since >= MB_WDT_MAXTIME) {
panic_plain("%s: %d waiters stuck for %u secs\n%s", __func__,
mb_waiters, since, mbuf_dump());
/* NOTREACHED */
}
/*
* Check if we are about to panic the system due
* to lack of mbufs and start defuncting sockets
* from processes that use too many sockets.
*
* We're always called with the mbuf_mlock held,
* so that also protects mbuf_watchdog_defunct_active.
*/
if (since >= MB_WDT_MAXTIME / 2) {
/*
* Start a thread to defunct sockets
* from apps that are over-using their socket
* buffers.
*/
if (defunct_tcall == NULL) {
defunct_tcall =
thread_call_allocate_with_options(mbuf_watchdog_defunct,
NULL,
THREAD_CALL_PRIORITY_KERNEL,
THREAD_CALL_OPTIONS_ONCE);
}
if (defunct_tcall != NULL) {
mbuf_watchdog_defunct_active = true;
thread_call_enter(defunct_tcall);
}
}
}
/*
* Called during blocking allocation. Returns TRUE if one or more objects
* are available at the per-CPU caches layer and that allocation should be
* retried at that level.
*/
static boolean_t
mbuf_sleep(mbuf_class_t class, unsigned int num, int wait)
{
boolean_t mcache_retry = FALSE;
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
/* Check if there's anything at the cache layer */
if (mbuf_cached_above(class, wait)) {
mcache_retry = TRUE;
goto done;
}
/* Nothing? Then try hard to get it from somewhere */
m_reclaim(class, num, (wait & MCR_COMP));
/* We tried hard and got something? */
if (m_infree(class) > 0) {
mbstat.m_wait++;
goto done;
} else if (mbuf_cached_above(class, wait)) {
mbstat.m_wait++;
mcache_retry = TRUE;
goto done;
} else if (wait & MCR_TRYHARD) {
mcache_retry = TRUE;
goto done;
}
/*
* There's really nothing for us right now; inform the
* cache(s) that there is a waiter below and go to sleep.
*/
mbuf_waiter_inc(class, (wait & MCR_COMP));
VERIFY(!(wait & MCR_NOSLEEP));
/*
* If this is the first waiter, arm the watchdog timer. Otherwise
* check if we need to panic the system due to watchdog timeout.
*/
if (mb_waiters == 0) {
microuptime(&mb_wdtstart);
} else {
mbuf_watchdog();
}
mb_waiters++;
m_region_expand(class) += m_total(class) + num;
/* wake up the worker thread */
if (mbuf_worker_ready &&
mbuf_worker_needs_wakeup) {
wakeup((caddr_t)&mbuf_worker_needs_wakeup);
mbuf_worker_needs_wakeup = FALSE;
}
mbwdog_logger("waiting (%d mbufs in class %s)", num, m_cname(class));
(void) msleep(mb_waitchan, mbuf_mlock, (PZERO - 1), m_cname(class), NULL);
mbwdog_logger("woke up (%d mbufs in class %s) ", num, m_cname(class));
/* We are now up; stop getting notified until next round */
mbuf_waiter_dec(class, (wait & MCR_COMP));
/* We waited and got something */
if (m_infree(class) > 0) {
mbstat.m_wait++;
goto done;
} else if (mbuf_cached_above(class, wait)) {
mbstat.m_wait++;
mcache_retry = TRUE;
}
done:
return mcache_retry;
}
__attribute__((noreturn))
static void
mbuf_worker_thread(void)
{
int mbuf_expand;
while (1) {
lck_mtx_lock(mbuf_mlock);
mbwdog_logger("worker thread running");
mbuf_worker_run_cnt++;
mbuf_expand = 0;
/*
* Allocations are based on page size, so if we have depleted
* the reserved spaces, try to free mbufs from the major classes.
*/
#if PAGE_SIZE == 4096
uint32_t m_mbclusters = m_total(MC_MBUF) >> NMBPCLSHIFT;
uint32_t m_clusters = m_total(MC_CL);
uint32_t m_bigclusters = m_total(MC_BIGCL) << NCLPBGSHIFT;
uint32_t sumclusters = m_mbclusters + m_clusters + m_bigclusters;
if (sumclusters >= nclusters) {
mbwdog_logger("reclaiming bigcl");
mbuf_drain_locked(TRUE);
m_reclaim(MC_BIGCL, 4, FALSE);
}
#else
uint32_t m_16kclusters = m_total(MC_16KCL);
if ((m_16kclusters << NCLPJCLSHIFT) >= njcl) {
mbwdog_logger("reclaiming 16kcl");
mbuf_drain_locked(TRUE);
m_reclaim(MC_16KCL, 4, FALSE);
}
#endif
if (m_region_expand(MC_CL) > 0) {
int n;
mb_expand_cl_cnt++;
/* Adjust to current number of cluster in use */
n = m_region_expand(MC_CL) -
(m_total(MC_CL) - m_infree(MC_CL));
if ((n + m_total(MC_CL)) > m_maxlimit(MC_CL)) {
n = m_maxlimit(MC_CL) - m_total(MC_CL);
}
if (n > 0) {
mb_expand_cl_total += n;
}
m_region_expand(MC_CL) = 0;
if (n > 0) {
mbwdog_logger("expanding MC_CL by %d", n);
freelist_populate(MC_CL, n, M_WAIT);
}
}
if (m_region_expand(MC_BIGCL) > 0) {
int n;
mb_expand_bigcl_cnt++;
/* Adjust to current number of 4 KB cluster in use */
n = m_region_expand(MC_BIGCL) -
(m_total(MC_BIGCL) - m_infree(MC_BIGCL));
if ((n + m_total(MC_BIGCL)) > m_maxlimit(MC_BIGCL)) {
n = m_maxlimit(MC_BIGCL) - m_total(MC_BIGCL);
}
if (n > 0) {
mb_expand_bigcl_total += n;
}
m_region_expand(MC_BIGCL) = 0;
if (n > 0) {
mbwdog_logger("expanding MC_BIGCL by %d", n);
freelist_populate(MC_BIGCL, n, M_WAIT);
}
}
if (m_region_expand(MC_16KCL) > 0) {
int n;
mb_expand_16kcl_cnt++;
/* Adjust to current number of 16 KB cluster in use */
n = m_region_expand(MC_16KCL) -
(m_total(MC_16KCL) - m_infree(MC_16KCL));
if ((n + m_total(MC_16KCL)) > m_maxlimit(MC_16KCL)) {
n = m_maxlimit(MC_16KCL) - m_total(MC_16KCL);
}
if (n > 0) {
mb_expand_16kcl_total += n;
}
m_region_expand(MC_16KCL) = 0;
if (n > 0) {
mbwdog_logger("expanding MC_16KCL by %d", n);
(void) freelist_populate(MC_16KCL, n, M_WAIT);
}
}
/*
* Because we can run out of memory before filling the mbuf
* map, we should not allocate more clusters than they are
* mbufs -- otherwise we could have a large number of useless
* clusters allocated.
*/
mbwdog_logger("totals: MC_MBUF %d MC_BIGCL %d MC_CL %d MC_16KCL %d",
m_total(MC_MBUF), m_total(MC_BIGCL), m_total(MC_CL),
m_total(MC_16KCL));
uint32_t total_mbufs = m_total(MC_MBUF);
uint32_t total_clusters = m_total(MC_BIGCL) + m_total(MC_CL) +
m_total(MC_16KCL);
if (total_mbufs < total_clusters) {
mbwdog_logger("expanding MC_MBUF by %d",
total_clusters - total_mbufs);
}
while (total_mbufs < total_clusters) {
mb_expand_cnt++;
if (freelist_populate(MC_MBUF, 1, M_WAIT) == 0) {
break;
}
total_mbufs = m_total(MC_MBUF);
total_clusters = m_total(MC_BIGCL) + m_total(MC_CL) +
m_total(MC_16KCL);
}
mbuf_worker_needs_wakeup = TRUE;
/*
* If there's a deadlock and we're not sending / receiving
* packets, net_uptime() won't be updated. Update it here
* so we are sure it's correct.
*/
net_update_uptime();
mbuf_worker_last_runtime = net_uptime();
assert_wait((caddr_t)&mbuf_worker_needs_wakeup,
THREAD_UNINT);
mbwdog_logger("worker thread sleeping");
lck_mtx_unlock(mbuf_mlock);
(void) thread_block((thread_continue_t)mbuf_worker_thread);
}
}
__attribute__((noreturn))
static void
mbuf_worker_thread_init(void)
{
mbuf_worker_ready++;
mbuf_worker_thread();
}
static mcl_slab_t *
slab_get(void *buf)
{
mcl_slabg_t *slg;
unsigned int ix, k;
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
VERIFY(MBUF_IN_MAP(buf));
ix = ((unsigned char *)buf - mbutl) >> MBSHIFT;
VERIFY(ix < maxslabgrp);
if ((slg = slabstbl[ix]) == NULL) {
/*
* In the current implementation, we never shrink the slabs
* table; if we attempt to reallocate a cluster group when
* it's already allocated, panic since this is a sign of a
* memory corruption (slabstbl[ix] got nullified).
*/
++slabgrp;
VERIFY(ix < slabgrp);
/*
* Slabs expansion can only be done single threaded; when
* we get here, it must be as a result of m_clalloc() which
* is serialized and therefore mb_clalloc_busy must be set.
*/
VERIFY(mb_clalloc_busy);
lck_mtx_unlock(mbuf_mlock);
/* This is a new buffer; create the slabs group for it */
slg = zalloc_permanent_type(mcl_slabg_t);
slg->slg_slab = zalloc_permanent(sizeof(mcl_slab_t) * NSLABSPMB,
ZALIGN(mcl_slab_t));
lck_mtx_lock(mbuf_mlock);
/*
* No other thread could have gone into m_clalloc() after
* we dropped the lock above, so verify that it's true.
*/
VERIFY(mb_clalloc_busy);
slabstbl[ix] = slg;
/* Chain each slab in the group to its forward neighbor */
for (k = 1; k < NSLABSPMB; k++) {
slg->slg_slab[k - 1].sl_next = &slg->slg_slab[k];
}
VERIFY(slg->slg_slab[NSLABSPMB - 1].sl_next == NULL);
/* And chain the last slab in the previous group to this */
if (ix > 0) {
VERIFY(slabstbl[ix - 1]->
slg_slab[NSLABSPMB - 1].sl_next == NULL);
slabstbl[ix - 1]->slg_slab[NSLABSPMB - 1].sl_next =
&slg->slg_slab[0];
}
}
ix = MTOPG(buf) % NSLABSPMB;
VERIFY(ix < NSLABSPMB);
return &slg->slg_slab[ix];
}
static void
slab_init(mcl_slab_t *sp, mbuf_class_t class, u_int32_t flags,
void *base, void *head, unsigned int len, int refcnt, int chunks)
{
sp->sl_class = class;
sp->sl_flags = flags;
sp->sl_base = base;
sp->sl_head = head;
sp->sl_len = len;
sp->sl_refcnt = refcnt;
sp->sl_chunks = chunks;
slab_detach(sp);
}
static void
slab_insert(mcl_slab_t *sp, mbuf_class_t class)
{
VERIFY(slab_is_detached(sp));
m_slab_cnt(class)++;
TAILQ_INSERT_TAIL(&m_slablist(class), sp, sl_link);
sp->sl_flags &= ~SLF_DETACHED;
/*
* If a buffer spans multiple contiguous pages then mark them as
* detached too
*/
if (class == MC_16KCL) {
int k;
for (k = 1; k < NSLABSP16KB; k++) {
sp = sp->sl_next;
/* Next slab must already be present */
VERIFY(sp != NULL && slab_is_detached(sp));
sp->sl_flags &= ~SLF_DETACHED;
}
}
}
static void
slab_remove(mcl_slab_t *sp, mbuf_class_t class)
{
int k;
VERIFY(!slab_is_detached(sp));
VERIFY(m_slab_cnt(class) > 0);
m_slab_cnt(class)--;
TAILQ_REMOVE(&m_slablist(class), sp, sl_link);
slab_detach(sp);
if (class == MC_16KCL) {
for (k = 1; k < NSLABSP16KB; k++) {
sp = sp->sl_next;
/* Next slab must already be present */
VERIFY(sp != NULL);
VERIFY(!slab_is_detached(sp));
slab_detach(sp);
}
}
}
static boolean_t
slab_inrange(mcl_slab_t *sp, void *buf)
{
return (uintptr_t)buf >= (uintptr_t)sp->sl_base &&
(uintptr_t)buf < ((uintptr_t)sp->sl_base + sp->sl_len);
}
#undef panic
static void
slab_nextptr_panic(mcl_slab_t *sp, void *addr)
{
int i;
unsigned int chunk_len = sp->sl_len / sp->sl_chunks;
uintptr_t buf = (uintptr_t)sp->sl_base;
for (i = 0; i < sp->sl_chunks; i++, buf += chunk_len) {
void *next = ((mcache_obj_t *)buf)->obj_next;
if (next != addr) {
continue;
}
if (!mclverify) {
if (next != NULL && !MBUF_IN_MAP(next)) {
mcache_t *cp = m_cache(sp->sl_class);
panic("%s: %s buffer %p in slab %p modified "
"after free at offset 0: %p out of range "
"[%p-%p)\n", __func__, cp->mc_name,
(void *)buf, sp, next, mbutl, embutl);
/* NOTREACHED */
}
} else {
mcache_audit_t *mca = mcl_audit_buf2mca(sp->sl_class,
(mcache_obj_t *)buf);
mcl_audit_verify_nextptr(next, mca);
}
}
}
static void
slab_detach(mcl_slab_t *sp)
{
sp->sl_link.tqe_next = (mcl_slab_t *)-1;
sp->sl_link.tqe_prev = (mcl_slab_t **)-1;
sp->sl_flags |= SLF_DETACHED;
}
static boolean_t
slab_is_detached(mcl_slab_t *sp)
{
return (intptr_t)sp->sl_link.tqe_next == -1 &&
(intptr_t)sp->sl_link.tqe_prev == -1 &&
(sp->sl_flags & SLF_DETACHED);
}
static void
mcl_audit_init(void *buf, mcache_audit_t **mca_list,
mcache_obj_t **con_list, size_t con_size, unsigned int num)
{
mcache_audit_t *mca, *mca_tail;
mcache_obj_t *con = NULL;
boolean_t save_contents = (con_list != NULL);
unsigned int i, ix;
ASSERT(num <= NMBPG);
ASSERT(con_list == NULL || con_size != 0);
ix = MTOPG(buf);
VERIFY(ix < maxclaudit);
/* Make sure we haven't been here before */
for (i = 0; i < num; i++) {
VERIFY(mclaudit[ix].cl_audit[i] == NULL);
}
mca = mca_tail = *mca_list;
if (save_contents) {
con = *con_list;
}
for (i = 0; i < num; i++) {
mcache_audit_t *next;
next = mca->mca_next;
bzero(mca, sizeof(*mca));
mca->mca_next = next;
mclaudit[ix].cl_audit[i] = mca;
/* Attach the contents buffer if requested */
if (save_contents) {
mcl_saved_contents_t *msc =
(mcl_saved_contents_t *)(void *)con;
VERIFY(msc != NULL);
VERIFY(IS_P2ALIGNED(msc, sizeof(u_int64_t)));
VERIFY(con_size == sizeof(*msc));
mca->mca_contents_size = con_size;
mca->mca_contents = msc;
con = con->obj_next;
bzero(mca->mca_contents, mca->mca_contents_size);
}
mca_tail = mca;
mca = mca->mca_next;
}
if (save_contents) {
*con_list = con;
}
*mca_list = mca_tail->mca_next;
mca_tail->mca_next = NULL;
}
static void
mcl_audit_free(void *buf, unsigned int num)
{
unsigned int i, ix;
mcache_audit_t *mca, *mca_list;
ix = MTOPG(buf);
VERIFY(ix < maxclaudit);
if (mclaudit[ix].cl_audit[0] != NULL) {
mca_list = mclaudit[ix].cl_audit[0];
for (i = 0; i < num; i++) {
mca = mclaudit[ix].cl_audit[i];
mclaudit[ix].cl_audit[i] = NULL;
if (mca->mca_contents) {
mcache_free(mcl_audit_con_cache,
mca->mca_contents);
}
}
mcache_free_ext(mcache_audit_cache,
(mcache_obj_t *)mca_list);
}
}
/*
* Given an address of a buffer (mbuf/2KB/4KB/16KB), return
* the corresponding audit structure for that buffer.
*/
static mcache_audit_t *
mcl_audit_buf2mca(mbuf_class_t class, mcache_obj_t *mobj)
{
mcache_audit_t *mca = NULL;
int ix = MTOPG(mobj), m_idx = 0;
unsigned char *page_addr;
VERIFY(ix < maxclaudit);
VERIFY(IS_P2ALIGNED(mobj, MIN(m_maxsize(class), PAGE_SIZE)));
page_addr = PGTOM(ix);
switch (class) {
case MC_MBUF:
/*
* For the mbuf case, find the index of the page
* used by the mbuf and use that index to locate the
* base address of the page. Then find out the
* mbuf index relative to the page base and use
* it to locate the audit structure.
*/
m_idx = MBPAGEIDX(page_addr, mobj);
VERIFY(m_idx < (int)NMBPG);
mca = mclaudit[ix].cl_audit[m_idx];
break;
case MC_CL:
/*
* Same thing as above, but for 2KB clusters in a page.
*/
m_idx = CLPAGEIDX(page_addr, mobj);
VERIFY(m_idx < (int)NCLPG);
mca = mclaudit[ix].cl_audit[m_idx];
break;
case MC_BIGCL:
m_idx = BCLPAGEIDX(page_addr, mobj);
VERIFY(m_idx < (int)NBCLPG);
mca = mclaudit[ix].cl_audit[m_idx];
break;
case MC_16KCL:
/*
* Same as above, but only return the first element.
*/
mca = mclaudit[ix].cl_audit[0];
break;
default:
VERIFY(0);
/* NOTREACHED */
}
return mca;
}
static void
mcl_audit_mbuf(mcache_audit_t *mca, void *addr, boolean_t composite,
boolean_t alloc)
{
struct mbuf *m = addr;
mcache_obj_t *next = ((mcache_obj_t *)m)->obj_next;
VERIFY(mca->mca_contents != NULL &&
mca->mca_contents_size == AUDIT_CONTENTS_SIZE);
if (mclverify) {
mcl_audit_verify_nextptr(next, mca);
}
if (!alloc) {
/* Save constructed mbuf fields */
mcl_audit_save_mbuf(m, mca);
if (mclverify) {
mcache_set_pattern(MCACHE_FREE_PATTERN, m,
m_maxsize(MC_MBUF));
}
((mcache_obj_t *)m)->obj_next = next;
return;
}
/* Check if the buffer has been corrupted while in freelist */
if (mclverify) {
mcache_audit_free_verify_set(mca, addr, 0, m_maxsize(MC_MBUF));
}
/* Restore constructed mbuf fields */
mcl_audit_restore_mbuf(m, mca, composite);
}
static void
mcl_audit_restore_mbuf(struct mbuf *m, mcache_audit_t *mca, boolean_t composite)
{
struct mbuf *ms = MCA_SAVED_MBUF_PTR(mca);
if (composite) {
struct mbuf *next = m->m_next;
VERIFY(ms->m_flags == M_EXT && m_get_rfa(ms) != NULL &&
MBUF_IS_COMPOSITE(ms));
VERIFY(mca->mca_contents_size == AUDIT_CONTENTS_SIZE);
/*
* We could have hand-picked the mbuf fields and restore
* them individually, but that will be a maintenance
* headache. Instead, restore everything that was saved;
* the mbuf layer will recheck and reinitialize anyway.
*/
bcopy(ms, m, MCA_SAVED_MBUF_SIZE);
m->m_next = next;
} else {
/*
* For a regular mbuf (no cluster attached) there's nothing
* to restore other than the type field, which is expected
* to be MT_FREE.
*/
m->m_type = ms->m_type;
}
mbuf_mcheck(m);
}
static void
mcl_audit_save_mbuf(struct mbuf *m, mcache_audit_t *mca)
{
VERIFY(mca->mca_contents_size == AUDIT_CONTENTS_SIZE);
mbuf_mcheck(m);
bcopy(m, MCA_SAVED_MBUF_PTR(mca), MCA_SAVED_MBUF_SIZE);
}
static void
mcl_audit_cluster(mcache_audit_t *mca, void *addr, size_t size, boolean_t alloc,
boolean_t save_next)
{
mcache_obj_t *next = ((mcache_obj_t *)addr)->obj_next;
if (!alloc) {
if (mclverify) {
mcache_set_pattern(MCACHE_FREE_PATTERN, addr, size);
}
if (save_next) {
mcl_audit_verify_nextptr(next, mca);
((mcache_obj_t *)addr)->obj_next = next;
}
} else if (mclverify) {
/* Check if the buffer has been corrupted while in freelist */
mcl_audit_verify_nextptr(next, mca);
mcache_audit_free_verify_set(mca, addr, 0, size);
}
}
static void
mcl_audit_scratch(mcache_audit_t *mca)
{
void *stack[MCACHE_STACK_DEPTH + 1];
mcl_scratch_audit_t *msa;
struct timeval now;
VERIFY(mca->mca_contents != NULL);
msa = MCA_SAVED_SCRATCH_PTR(mca);
msa->msa_pthread = msa->msa_thread;
msa->msa_thread = current_thread();
bcopy(msa->msa_stack, msa->msa_pstack, sizeof(msa->msa_pstack));
msa->msa_pdepth = msa->msa_depth;
bzero(stack, sizeof(stack));
msa->msa_depth = OSBacktrace(stack, MCACHE_STACK_DEPTH + 1) - 1;
bcopy(&stack[1], msa->msa_stack, sizeof(msa->msa_stack));
msa->msa_ptstamp = msa->msa_tstamp;
microuptime(&now);
/* tstamp is in ms relative to base_ts */
msa->msa_tstamp = ((now.tv_usec - mb_start.tv_usec) / 1000);
if ((now.tv_sec - mb_start.tv_sec) > 0) {
msa->msa_tstamp += ((now.tv_sec - mb_start.tv_sec) * 1000);
}
}
__abortlike
static void
mcl_audit_mcheck_panic(struct mbuf *m)
{
char buf[DUMP_MCA_BUF_SIZE];
mcache_audit_t *mca;
MRANGE(m);
mca = mcl_audit_buf2mca(MC_MBUF, (mcache_obj_t *)m);
panic("mcl_audit: freed mbuf %p with type 0x%x (instead of 0x%x)\n%s",
m, (u_int16_t)m->m_type, MT_FREE, mcache_dump_mca(buf, mca));
/* NOTREACHED */
}
__abortlike
static void
mcl_audit_verify_nextptr_panic(void *next, mcache_audit_t *mca)
{
char buf[DUMP_MCA_BUF_SIZE];
panic("mcl_audit: buffer %p modified after free at offset 0: "
"%p out of range [%p-%p)\n%s\n",
mca->mca_addr, next, mbutl, embutl, mcache_dump_mca(buf, mca));
/* NOTREACHED */
}
static void
mcl_audit_verify_nextptr(void *next, mcache_audit_t *mca)
{
if (next != NULL && !MBUF_IN_MAP(next) &&
(next != (void *)MCACHE_FREE_PATTERN || !mclverify)) {
mcl_audit_verify_nextptr_panic(next, mca);
}
}
static uintptr_t
hash_mix(uintptr_t x)
{
#ifndef __LP64__
x += ~(x << 15);
x ^= (x >> 10);
x += (x << 3);
x ^= (x >> 6);
x += ~(x << 11);
x ^= (x >> 16);
#else
x += ~(x << 32);
x ^= (x >> 22);
x += ~(x << 13);
x ^= (x >> 8);
x += (x << 3);
x ^= (x >> 15);
x += ~(x << 27);
x ^= (x >> 31);
#endif
return x;
}
static uint32_t
hashbacktrace(uintptr_t* bt, uint32_t depth, uint32_t max_size)
{
uintptr_t hash = 0;
uintptr_t mask = max_size - 1;
while (depth) {
hash += bt[--depth];
}
hash = hash_mix(hash) & mask;
assert(hash < max_size);
return (uint32_t) hash;
}
static uint32_t
hashaddr(uintptr_t pt, uint32_t max_size)
{
uintptr_t hash = 0;
uintptr_t mask = max_size - 1;
hash = hash_mix(pt) & mask;
assert(hash < max_size);
return (uint32_t) hash;
}
/* This function turns on mbuf leak detection */
static void
mleak_activate(void)
{
mleak_table.mleak_sample_factor = MLEAK_SAMPLE_FACTOR;
PE_parse_boot_argn("mleak_sample_factor",
&mleak_table.mleak_sample_factor,
sizeof(mleak_table.mleak_sample_factor));
if (mleak_table.mleak_sample_factor == 0) {
mclfindleak = 0;
}
if (mclfindleak == 0) {
return;
}
vm_size_t alloc_size =
mleak_alloc_buckets * sizeof(struct mallocation);
vm_size_t trace_size = mleak_trace_buckets * sizeof(struct mtrace);
mleak_allocations = zalloc_permanent(alloc_size, ZALIGN(struct mallocation));
mleak_traces = zalloc_permanent(trace_size, ZALIGN(struct mtrace));
mleak_stat = zalloc_permanent(MLEAK_STAT_SIZE(MLEAK_NUM_TRACES),
ZALIGN(mleak_stat_t));
mleak_stat->ml_cnt = MLEAK_NUM_TRACES;
#ifdef __LP64__
mleak_stat->ml_isaddr64 = 1;
#endif /* __LP64__ */
}
static void
mleak_logger(u_int32_t num, mcache_obj_t *addr, boolean_t alloc)
{
int temp;
if (mclfindleak == 0) {
return;
}
if (!alloc) {
return mleak_free(addr);
}
temp = os_atomic_inc_orig(&mleak_table.mleak_capture, relaxed);
if ((temp % mleak_table.mleak_sample_factor) == 0 && addr != NULL) {
uintptr_t bt[MLEAK_STACK_DEPTH];
unsigned int logged = backtrace(bt, MLEAK_STACK_DEPTH, NULL, NULL);
mleak_log(bt, addr, logged, num);
}
}
/*
* This function records the allocation in the mleak_allocations table
* and the backtrace in the mleak_traces table; if allocation slot is in use,
* replace old allocation with new one if the trace slot is in use, return
* (or increment refcount if same trace).
*/
static boolean_t
mleak_log(uintptr_t *bt, mcache_obj_t *addr, uint32_t depth, int num)
{
struct mallocation *allocation;
struct mtrace *trace;
uint32_t trace_index;
/* Quit if someone else modifying the tables */
if (!lck_mtx_try_lock_spin(mleak_lock)) {
mleak_table.total_conflicts++;
return FALSE;
}
allocation = &mleak_allocations[hashaddr((uintptr_t)addr,
mleak_alloc_buckets)];
trace_index = hashbacktrace(bt, depth, mleak_trace_buckets);
trace = &mleak_traces[trace_index];
VERIFY(allocation <= &mleak_allocations[mleak_alloc_buckets - 1]);
VERIFY(trace <= &mleak_traces[mleak_trace_buckets - 1]);
allocation->hitcount++;
trace->hitcount++;
/*
* If the allocation bucket we want is occupied
* and the occupier has the same trace, just bail.
*/
if (allocation->element != NULL &&
trace_index == allocation->trace_index) {
mleak_table.alloc_collisions++;
lck_mtx_unlock(mleak_lock);
return TRUE;
}
/*
* Store the backtrace in the traces array;
* Size of zero = trace bucket is free.
*/
if (trace->allocs > 0 &&
bcmp(trace->addr, bt, (depth * sizeof(uintptr_t))) != 0) {
/* Different, unique trace, but the same hash! Bail out. */
trace->collisions++;
mleak_table.trace_collisions++;
lck_mtx_unlock(mleak_lock);
return TRUE;
} else if (trace->allocs > 0) {
/* Same trace, already added, so increment refcount */
trace->allocs++;
} else {
/* Found an unused trace bucket, so record the trace here */
if (trace->depth != 0) {
/* this slot previously used but not currently in use */
mleak_table.trace_overwrites++;
}
mleak_table.trace_recorded++;
trace->allocs = 1;
memcpy(trace->addr, bt, (depth * sizeof(uintptr_t)));
trace->depth = depth;
trace->collisions = 0;
}
/* Step 2: Store the allocation record in the allocations array */
if (allocation->element != NULL) {
/*
* Replace an existing allocation. No need to preserve
* because only a subset of the allocations are being
* recorded anyway.
*/
mleak_table.alloc_collisions++;
} else if (allocation->trace_index != 0) {
mleak_table.alloc_overwrites++;
}
allocation->element = addr;
allocation->trace_index = trace_index;
allocation->count = num;
mleak_table.alloc_recorded++;
mleak_table.outstanding_allocs++;
lck_mtx_unlock(mleak_lock);
return TRUE;
}
static void
mleak_free(mcache_obj_t *addr)
{
while (addr != NULL) {
struct mallocation *allocation = &mleak_allocations
[hashaddr((uintptr_t)addr, mleak_alloc_buckets)];
if (allocation->element == addr &&
allocation->trace_index < mleak_trace_buckets) {
lck_mtx_lock_spin(mleak_lock);
if (allocation->element == addr &&
allocation->trace_index < mleak_trace_buckets) {
struct mtrace *trace;
trace = &mleak_traces[allocation->trace_index];
/* allocs = 0 means trace bucket is unused */
if (trace->allocs > 0) {
trace->allocs--;
}
if (trace->allocs == 0) {
trace->depth = 0;
}
/* NULL element means alloc bucket is unused */
allocation->element = NULL;
mleak_table.outstanding_allocs--;
}
lck_mtx_unlock(mleak_lock);
}
addr = addr->obj_next;
}
}
static void
mleak_sort_traces()
{
int i, j, k;
struct mtrace *swap;
for (i = 0; i < MLEAK_NUM_TRACES; i++) {
mleak_top_trace[i] = NULL;
}
for (i = 0, j = 0; j < MLEAK_NUM_TRACES && i < mleak_trace_buckets; i++) {
if (mleak_traces[i].allocs <= 0) {
continue;
}
mleak_top_trace[j] = &mleak_traces[i];
for (k = j; k > 0; k--) {
if (mleak_top_trace[k]->allocs <=
mleak_top_trace[k - 1]->allocs) {
break;
}
swap = mleak_top_trace[k - 1];
mleak_top_trace[k - 1] = mleak_top_trace[k];
mleak_top_trace[k] = swap;
}
j++;
}
j--;
for (; i < mleak_trace_buckets; i++) {
if (mleak_traces[i].allocs <= mleak_top_trace[j]->allocs) {
continue;
}
mleak_top_trace[j] = &mleak_traces[i];
for (k = j; k > 0; k--) {
if (mleak_top_trace[k]->allocs <=
mleak_top_trace[k - 1]->allocs) {
break;
}
swap = mleak_top_trace[k - 1];
mleak_top_trace[k - 1] = mleak_top_trace[k];
mleak_top_trace[k] = swap;
}
}
}
static void
mleak_update_stats()
{
mleak_trace_stat_t *mltr;
int i;
VERIFY(mleak_stat != NULL);
#ifdef __LP64__
VERIFY(mleak_stat->ml_isaddr64);
#else
VERIFY(!mleak_stat->ml_isaddr64);
#endif /* !__LP64__ */
VERIFY(mleak_stat->ml_cnt == MLEAK_NUM_TRACES);
mleak_sort_traces();
mltr = &mleak_stat->ml_trace[0];
bzero(mltr, sizeof(*mltr) * MLEAK_NUM_TRACES);
for (i = 0; i < MLEAK_NUM_TRACES; i++) {
int j;
if (mleak_top_trace[i] == NULL ||
mleak_top_trace[i]->allocs == 0) {
continue;
}
mltr->mltr_collisions = mleak_top_trace[i]->collisions;
mltr->mltr_hitcount = mleak_top_trace[i]->hitcount;
mltr->mltr_allocs = mleak_top_trace[i]->allocs;
mltr->mltr_depth = mleak_top_trace[i]->depth;
VERIFY(mltr->mltr_depth <= MLEAK_STACK_DEPTH);
for (j = 0; j < mltr->mltr_depth; j++) {
mltr->mltr_addr[j] = mleak_top_trace[i]->addr[j];
}
mltr++;
}
}
static struct mbtypes {
int mt_type;
const char *mt_name;
} mbtypes[] = {
{ MT_DATA, "data" },
{ MT_OOBDATA, "oob data" },
{ MT_CONTROL, "ancillary data" },
{ MT_HEADER, "packet headers" },
{ MT_SOCKET, "socket structures" },
{ MT_PCB, "protocol control blocks" },
{ MT_RTABLE, "routing table entries" },
{ MT_HTABLE, "IMP host table entries" },
{ MT_ATABLE, "address resolution tables" },
{ MT_FTABLE, "fragment reassembly queue headers" },
{ MT_SONAME, "socket names and addresses" },
{ MT_SOOPTS, "socket options" },
{ MT_RIGHTS, "access rights" },
{ MT_IFADDR, "interface addresses" },
{ MT_TAG, "packet tags" },
{ 0, NULL }
};
#define MBUF_DUMP_BUF_CHK() { \
clen -= k; \
if (clen < 1) \
goto done; \
c += k; \
}
static char *
mbuf_dump(void)
{
unsigned long totmem = 0, totfree = 0, totmbufs, totused, totpct,
totreturned = 0;
u_int32_t m_mbufs = 0, m_clfree = 0, m_bigclfree = 0;
u_int32_t m_mbufclfree = 0, m_mbufbigclfree = 0;
u_int32_t m_16kclusters = 0, m_16kclfree = 0, m_mbuf16kclfree = 0;
int nmbtypes = sizeof(mbstat.m_mtypes) / sizeof(short);
uint8_t seen[256];
struct mbtypes *mp;
mb_class_stat_t *sp;
mleak_trace_stat_t *mltr;
char *c = mbuf_dump_buf;
int i, j, k, clen = MBUF_DUMP_BUF_SIZE;
struct mbuf_watchdog_defunct_args args = {};
mbuf_dump_buf[0] = '\0';
/* synchronize all statistics in the mbuf table */
mbuf_stat_sync();
mbuf_mtypes_sync();
sp = &mb_stat->mbs_class[0];
for (i = 0; i < mb_stat->mbs_cnt; i++, sp++) {
u_int32_t mem;
if (m_class(i) == MC_MBUF) {
m_mbufs = sp->mbcl_active;
} else if (m_class(i) == MC_CL) {
m_clfree = sp->mbcl_total - sp->mbcl_active;
} else if (m_class(i) == MC_BIGCL) {
m_bigclfree = sp->mbcl_total - sp->mbcl_active;
} else if (m_class(i) == MC_16KCL) {
m_16kclfree = sp->mbcl_total - sp->mbcl_active;
m_16kclusters = sp->mbcl_total;
} else if (m_class(i) == MC_MBUF_CL) {
m_mbufclfree = sp->mbcl_total - sp->mbcl_active;
} else if (m_class(i) == MC_MBUF_BIGCL) {
m_mbufbigclfree = sp->mbcl_total - sp->mbcl_active;
} else if (m_class(i) == MC_MBUF_16KCL) {
m_mbuf16kclfree = sp->mbcl_total - sp->mbcl_active;
}
mem = sp->mbcl_ctotal * sp->mbcl_size;
totmem += mem;
totfree += (sp->mbcl_mc_cached + sp->mbcl_infree) *
sp->mbcl_size;
totreturned += sp->mbcl_release_cnt;
}
/* adjust free counts to include composite caches */
m_clfree += m_mbufclfree;
m_bigclfree += m_mbufbigclfree;
m_16kclfree += m_mbuf16kclfree;
totmbufs = 0;
for (mp = mbtypes; mp->mt_name != NULL; mp++) {
totmbufs += mbstat.m_mtypes[mp->mt_type];
}
if (totmbufs > m_mbufs) {
totmbufs = m_mbufs;
}
k = scnprintf(c, clen, "%lu/%u mbufs in use:\n", totmbufs, m_mbufs);
MBUF_DUMP_BUF_CHK();
bzero(&seen, sizeof(seen));
for (mp = mbtypes; mp->mt_name != NULL; mp++) {
if (mbstat.m_mtypes[mp->mt_type] != 0) {
seen[mp->mt_type] = 1;
k = scnprintf(c, clen, "\t%u mbufs allocated to %s\n",
mbstat.m_mtypes[mp->mt_type], mp->mt_name);
MBUF_DUMP_BUF_CHK();
}
}
seen[MT_FREE] = 1;
for (i = 0; i < nmbtypes; i++) {
if (!seen[i] && mbstat.m_mtypes[i] != 0) {
k = scnprintf(c, clen, "\t%u mbufs allocated to "
"<mbuf type %d>\n", mbstat.m_mtypes[i], i);
MBUF_DUMP_BUF_CHK();
}
}
if ((m_mbufs - totmbufs) > 0) {
k = scnprintf(c, clen, "\t%lu mbufs allocated to caches\n",
m_mbufs - totmbufs);
MBUF_DUMP_BUF_CHK();
}
k = scnprintf(c, clen, "%u/%u mbuf 2KB clusters in use\n"
"%u/%u mbuf 4KB clusters in use\n",
(unsigned int)(mbstat.m_clusters - m_clfree),
(unsigned int)mbstat.m_clusters,
(unsigned int)(mbstat.m_bigclusters - m_bigclfree),
(unsigned int)mbstat.m_bigclusters);
MBUF_DUMP_BUF_CHK();
k = scnprintf(c, clen, "%u/%u mbuf %uKB clusters in use\n",
m_16kclusters - m_16kclfree, m_16kclusters,
njclbytes / 1024);
MBUF_DUMP_BUF_CHK();
totused = totmem - totfree;
if (totmem == 0) {
totpct = 0;
} else if (totused < (ULONG_MAX / 100)) {
totpct = (totused * 100) / totmem;
} else {
u_long totmem1 = totmem / 100;
u_long totused1 = totused / 100;
totpct = (totused1 * 100) / totmem1;
}
k = scnprintf(c, clen, "%lu KB allocated to network (approx. %lu%% "
"in use)\n", totmem / 1024, totpct);
MBUF_DUMP_BUF_CHK();
k = scnprintf(c, clen, "%lu KB returned to the system\n",
totreturned / 1024);
MBUF_DUMP_BUF_CHK();
net_update_uptime();
k = scnprintf(c, clen,
"worker thread runs: %u, expansions: %llu, cl %llu/%llu, "
"bigcl %llu/%llu, 16k %llu/%llu\n", mbuf_worker_run_cnt,
mb_expand_cnt, mb_expand_cl_cnt, mb_expand_cl_total,
mb_expand_bigcl_cnt, mb_expand_bigcl_total, mb_expand_16kcl_cnt,
mb_expand_16kcl_total);
MBUF_DUMP_BUF_CHK();
if (mbuf_worker_last_runtime != 0) {
k = scnprintf(c, clen, "worker thread last run time: "
"%llu (%llu seconds ago)\n",
mbuf_worker_last_runtime,
net_uptime() - mbuf_worker_last_runtime);
MBUF_DUMP_BUF_CHK();
}
if (mbuf_drain_last_runtime != 0) {
k = scnprintf(c, clen, "drain routine last run time: "
"%llu (%llu seconds ago)\n",
mbuf_drain_last_runtime,
net_uptime() - mbuf_drain_last_runtime);
MBUF_DUMP_BUF_CHK();
}
/*
* Log where the most mbufs have accumulated:
* - Process socket buffers
* - TCP reassembly queue
* - Interface AQM queue (output) and DLIL input queue
*/
args.non_blocking = true;
proc_iterate(PROC_ALLPROCLIST,
mbuf_watchdog_defunct_iterate, &args, NULL, NULL);
if (args.top_app != NULL) {
k = scnprintf(c, clen, "\ntop proc mbuf space %u bytes by %s:%d\n",
args.top_app_space_used,
proc_name_address(args.top_app),
proc_pid(args.top_app));
proc_rele(args.top_app);
}
MBUF_DUMP_BUF_CHK();
#if INET
k = dump_tcp_reass_qlen(c, clen);
MBUF_DUMP_BUF_CHK();
#endif /* INET */
#if MPTCP
k = dump_mptcp_reass_qlen(c, clen);
MBUF_DUMP_BUF_CHK();
#endif /* MPTCP */
#if NETWORKING
k = dlil_dump_top_if_qlen(c, clen);
MBUF_DUMP_BUF_CHK();
#endif /* NETWORKING */
/* mbuf leak detection statistics */
mleak_update_stats();
k = scnprintf(c, clen, "\nmbuf leak detection table:\n");
MBUF_DUMP_BUF_CHK();
k = scnprintf(c, clen, "\ttotal captured: %u (one per %u)\n",
mleak_table.mleak_capture / mleak_table.mleak_sample_factor,
mleak_table.mleak_sample_factor);
MBUF_DUMP_BUF_CHK();
k = scnprintf(c, clen, "\ttotal allocs outstanding: %llu\n",
mleak_table.outstanding_allocs);
MBUF_DUMP_BUF_CHK();
k = scnprintf(c, clen, "\tnew hash recorded: %llu allocs, %llu traces\n",
mleak_table.alloc_recorded, mleak_table.trace_recorded);
MBUF_DUMP_BUF_CHK();
k = scnprintf(c, clen, "\thash collisions: %llu allocs, %llu traces\n",
mleak_table.alloc_collisions, mleak_table.trace_collisions);
MBUF_DUMP_BUF_CHK();
k = scnprintf(c, clen, "\toverwrites: %llu allocs, %llu traces\n",
mleak_table.alloc_overwrites, mleak_table.trace_overwrites);
MBUF_DUMP_BUF_CHK();
k = scnprintf(c, clen, "\tlock conflicts: %llu\n\n",
mleak_table.total_conflicts);
MBUF_DUMP_BUF_CHK();
k = scnprintf(c, clen, "top %d outstanding traces:\n",
mleak_stat->ml_cnt);
MBUF_DUMP_BUF_CHK();
for (i = 0; i < mleak_stat->ml_cnt; i++) {
mltr = &mleak_stat->ml_trace[i];
k = scnprintf(c, clen, "[%d] %llu outstanding alloc(s), "
"%llu hit(s), %llu collision(s)\n", (i + 1),
mltr->mltr_allocs, mltr->mltr_hitcount,
mltr->mltr_collisions);
MBUF_DUMP_BUF_CHK();
}
if (mleak_stat->ml_isaddr64) {
k = scnprintf(c, clen, MB_LEAK_HDR_64);
} else {
k = scnprintf(c, clen, MB_LEAK_HDR_32);
}
MBUF_DUMP_BUF_CHK();
for (i = 0; i < MLEAK_STACK_DEPTH; i++) {
k = scnprintf(c, clen, "%2d: ", (i + 1));
MBUF_DUMP_BUF_CHK();
for (j = 0; j < mleak_stat->ml_cnt; j++) {
mltr = &mleak_stat->ml_trace[j];
if (i < mltr->mltr_depth) {
if (mleak_stat->ml_isaddr64) {
k = scnprintf(c, clen, "0x%0llx ",
(uint64_t)VM_KERNEL_UNSLIDE(
mltr->mltr_addr[i]));
} else {
k = scnprintf(c, clen,
"0x%08x ",
(uint32_t)VM_KERNEL_UNSLIDE(
mltr->mltr_addr[i]));
}
} else {
if (mleak_stat->ml_isaddr64) {
k = scnprintf(c, clen,
MB_LEAK_SPACING_64);
} else {
k = scnprintf(c, clen,
MB_LEAK_SPACING_32);
}
}
MBUF_DUMP_BUF_CHK();
}
k = scnprintf(c, clen, "\n");
MBUF_DUMP_BUF_CHK();
}
done:
return mbuf_dump_buf;
}
#undef MBUF_DUMP_BUF_CHK
/*
* This routine is reserved for mbuf_get_driver_scratch(); clients inside
* xnu that intend on utilizing the module-private area should directly
* refer to the pkt_mpriv structure in the pkthdr. They are also expected
* to set and clear PKTF_PRIV_GUARDED, while owning the packet and prior
* to handing it off to another module, respectively.
*/
u_int32_t
m_scratch_get(struct mbuf *m, u_int8_t **p)
{
struct pkthdr *pkt = &m->m_pkthdr;
VERIFY(m->m_flags & M_PKTHDR);
/* See comments in <rdar://problem/14040693> */
if (pkt->pkt_flags & PKTF_PRIV_GUARDED) {
panic_plain("Invalid attempt to access guarded module-private "
"area: mbuf %p, pkt_flags 0x%x\n", m, pkt->pkt_flags);
/* NOTREACHED */
}
if (mcltrace) {
mcache_audit_t *mca;
lck_mtx_lock(mbuf_mlock);
mca = mcl_audit_buf2mca(MC_MBUF, (mcache_obj_t *)m);
if (mca->mca_uflags & MB_SCVALID) {
mcl_audit_scratch(mca);
}
lck_mtx_unlock(mbuf_mlock);
}
*p = (u_int8_t *)&pkt->pkt_mpriv;
return sizeof(pkt->pkt_mpriv);
}
/*
* Simple routine to avoid taking the lock when we can't run the
* mbuf drain.
*/
static int
mbuf_drain_checks(boolean_t ignore_waiters)
{
if (mb_drain_maxint == 0) {
return 0;
}
if (!ignore_waiters && mb_waiters != 0) {
return 0;
}
return 1;
}
/*
* Called by the VM when there's memory pressure or when we exhausted
* the 4k/16k reserved space.
*/
static void
mbuf_drain_locked(boolean_t ignore_waiters)
{
mbuf_class_t mc;
mcl_slab_t *sp, *sp_tmp, *nsp;
unsigned int num, k, interval, released = 0;
unsigned long total_mem = 0, use_mem = 0;
boolean_t ret, purge_caches = FALSE;
ppnum_t offset;
mcache_obj_t *obj;
unsigned long per;
static unsigned char scratch[32];
static ppnum_t scratch_pa = 0;
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
if (!mbuf_drain_checks(ignore_waiters)) {
return;
}
if (scratch_pa == 0) {
bzero(scratch, sizeof(scratch));
scratch_pa = pmap_find_phys(kernel_pmap, (addr64_t)scratch);
VERIFY(scratch_pa);
} else if (mclverify) {
/*
* Panic if a driver wrote to our scratch memory.
*/
for (k = 0; k < sizeof(scratch); k++) {
if (scratch[k]) {
panic("suspect DMA to freed address");
}
}
}
/*
* Don't free memory too often as that could cause excessive
* waiting times for mbufs. Purge caches if we were asked to drain
* in the last 5 minutes.
*/
if (mbuf_drain_last_runtime != 0) {
interval = net_uptime() - mbuf_drain_last_runtime;
if (interval <= mb_drain_maxint) {
return;
}
if (interval <= mb_drain_maxint * 5) {
purge_caches = TRUE;
}
}
mbuf_drain_last_runtime = net_uptime();
/*
* Don't free any memory if we're using 60% or more.
*/
for (mc = 0; mc < MC_MAX; mc++) {
total_mem += m_total(mc) * m_maxsize(mc);
use_mem += m_active(mc) * m_maxsize(mc);
}
per = (use_mem * 100) / total_mem;
if (per >= 60) {
return;
}
/*
* Purge all the caches. This effectively disables
* caching for a few seconds, but the mbuf worker thread will
* re-enable them again.
*/
if (purge_caches == TRUE) {
for (mc = 0; mc < MC_MAX; mc++) {
if (m_total(mc) < m_avgtotal(mc)) {
continue;
}
lck_mtx_unlock(mbuf_mlock);
ret = mcache_purge_cache(m_cache(mc), FALSE);
lck_mtx_lock(mbuf_mlock);
if (ret == TRUE) {
m_purge_cnt(mc)++;
}
}
}
/*
* Move the objects from the composite class freelist to
* the rudimentary slabs list, but keep at least 10% of the average
* total in the freelist.
*/
for (mc = 0; mc < MC_MAX; mc++) {
while (m_cobjlist(mc) &&
m_total(mc) < m_avgtotal(mc) &&
m_infree(mc) > 0.1 * m_avgtotal(mc) + m_minlimit(mc)) {
obj = m_cobjlist(mc);
m_cobjlist(mc) = obj->obj_next;
obj->obj_next = NULL;
num = cslab_free(mc, obj, 1);
VERIFY(num == 1);
m_free_cnt(mc)++;
m_infree(mc)--;
/* cslab_free() handles m_total */
}
}
/*
* Free the buffers present in the slab list up to 10% of the total
* average per class.
*
* We walk the list backwards in an attempt to reduce fragmentation.
*/
for (mc = MC_MAX - 1; (int)mc >= 0; mc--) {
TAILQ_FOREACH_SAFE(sp, &m_slablist(mc), sl_link, sp_tmp) {
/*
* Process only unused slabs occupying memory.
*/
if (sp->sl_refcnt != 0 || sp->sl_len == 0 ||
sp->sl_base == NULL) {
continue;
}
if (m_total(mc) < m_avgtotal(mc) ||
m_infree(mc) < 0.1 * m_avgtotal(mc) + m_minlimit(mc)) {
break;
}
slab_remove(sp, mc);
switch (mc) {
case MC_MBUF:
m_infree(mc) -= NMBPG;
m_total(mc) -= NMBPG;
if (mclaudit != NULL) {
mcl_audit_free(sp->sl_base, NMBPG);
}
break;
case MC_CL:
m_infree(mc) -= NCLPG;
m_total(mc) -= NCLPG;
if (mclaudit != NULL) {
mcl_audit_free(sp->sl_base, NMBPG);
}
break;
case MC_BIGCL:
{
m_infree(mc) -= NBCLPG;
m_total(mc) -= NBCLPG;
if (mclaudit != NULL) {
mcl_audit_free(sp->sl_base, NMBPG);
}
break;
}
case MC_16KCL:
m_infree(mc)--;
m_total(mc)--;
for (nsp = sp, k = 1; k < NSLABSP16KB; k++) {
nsp = nsp->sl_next;
VERIFY(nsp->sl_refcnt == 0 &&
nsp->sl_base != NULL &&
nsp->sl_len == 0);
slab_init(nsp, 0, 0, NULL, NULL, 0, 0,
0);
nsp->sl_flags = 0;
}
if (mclaudit != NULL) {
if (sp->sl_len == PAGE_SIZE) {
mcl_audit_free(sp->sl_base,
NMBPG);
} else {
mcl_audit_free(sp->sl_base, 1);
}
}
break;
default:
/*
* The composite classes have their own
* freelist (m_cobjlist), so we only
* process rudimentary classes here.
*/
VERIFY(0);
}
m_release_cnt(mc) += m_size(mc);
released += m_size(mc);
VERIFY(sp->sl_base != NULL &&
sp->sl_len >= PAGE_SIZE);
offset = MTOPG(sp->sl_base);
/*
* Make sure the IOMapper points to a valid, but
* bogus, address. This should prevent further DMA
* accesses to freed memory.
*/
IOMapperInsertPage(mcl_paddr_base, offset, scratch_pa);
mcl_paddr[offset] = 0;
kmem_free(mb_map, (vm_offset_t)sp->sl_base,
sp->sl_len);
slab_init(sp, 0, 0, NULL, NULL, 0, 0, 0);
sp->sl_flags = 0;
}
}
mbstat.m_drain++;
mbstat.m_bigclusters = m_total(MC_BIGCL);
mbstat.m_clusters = m_total(MC_CL);
mbstat.m_mbufs = m_total(MC_MBUF);
mbuf_stat_sync();
mbuf_mtypes_sync();
}
__private_extern__ void
mbuf_drain(boolean_t ignore_waiters)
{
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_NOTOWNED);
if (!mbuf_drain_checks(ignore_waiters)) {
return;
}
lck_mtx_lock(mbuf_mlock);
mbuf_drain_locked(ignore_waiters);
lck_mtx_unlock(mbuf_mlock);
}
static int
m_drain_force_sysctl SYSCTL_HANDLER_ARGS
{
#pragma unused(arg1, arg2)
int val = 0, err;
err = sysctl_handle_int(oidp, &val, 0, req);
if (err != 0 || req->newptr == USER_ADDR_NULL) {
return err;
}
if (val) {
mbuf_drain(TRUE);
}
return err;
}
#if DEBUG || DEVELOPMENT
__printflike(3, 4)
static void
_mbwdog_logger(const char *func, const int line, const char *fmt, ...)
{
va_list ap;
struct timeval now;
char str[384], p[256];
int len;
LCK_MTX_ASSERT(mbuf_mlock, LCK_MTX_ASSERT_OWNED);
if (mbwdog_logging == NULL) {
/*
* This might block under a mutex, which isn't really great,
* but this happens once, so we'll live.
*/
mbwdog_logging = zalloc_permanent(mbwdog_logging_size,
ZALIGN_NONE);
}
va_start(ap, fmt);
vsnprintf(p, sizeof(p), fmt, ap);
va_end(ap);
microuptime(&now);
len = scnprintf(str, sizeof(str),
"\n%ld.%d (%d/%llx) %s:%d %s",
now.tv_sec, now.tv_usec,
proc_getpid(current_proc()),
(uint64_t)VM_KERNEL_ADDRPERM(current_thread()),
func, line, p);
if (len < 0) {
return;
}
if (mbwdog_logging_used + len > mbwdog_logging_size) {
mbwdog_logging_used = mbwdog_logging_used / 2;
memmove(mbwdog_logging, mbwdog_logging + mbwdog_logging_used,
mbwdog_logging_size - mbwdog_logging_used);
mbwdog_logging[mbwdog_logging_used] = 0;
}
strlcat(mbwdog_logging, str, mbwdog_logging_size);
mbwdog_logging_used += len;
}
#endif // DEBUG || DEVELOPMENT
static void
mtracelarge_register(size_t size)
{
int i;
struct mtracelarge *trace;
uintptr_t bt[MLEAK_STACK_DEPTH];
unsigned int depth;
depth = backtrace(bt, MLEAK_STACK_DEPTH, NULL, NULL);
/* Check if this entry is already on the list. */
for (i = 0; i < MTRACELARGE_NUM_TRACES; i++) {
trace = &mtracelarge_table[i];
if (trace->size == size && trace->depth == depth &&
memcmp(bt, trace->addr, depth * sizeof(uintptr_t)) == 0) {
return;
}
}
for (i = 0; i < MTRACELARGE_NUM_TRACES; i++) {
trace = &mtracelarge_table[i];
if (size > trace->size) {
trace->depth = depth;
memcpy(trace->addr, bt, depth * sizeof(uintptr_t));
trace->size = size;
break;
}
}
}
#if DEBUG || DEVELOPMENT
static int
mbuf_wd_dump_sysctl SYSCTL_HANDLER_ARGS
{
char *str;
ifnet_head_lock_shared();
lck_mtx_lock(mbuf_mlock);
str = mbuf_dump();
lck_mtx_unlock(mbuf_mlock);
ifnet_head_done();
return sysctl_io_string(req, str, 0, 0, NULL);
}
#endif /* DEBUG || DEVELOPMENT */
SYSCTL_DECL(_kern_ipc);
#if DEBUG || DEVELOPMENT
#if SKYWALK
SYSCTL_UINT(_kern_ipc, OID_AUTO, mc_threshold_scale_factor,
CTLFLAG_RW | CTLFLAG_LOCKED, &mc_threshold_scale_down_factor,
MC_THRESHOLD_SCALE_DOWN_FACTOR,
"scale down factor for mbuf cache thresholds");
#endif /* SKYWALK */
SYSCTL_PROC(_kern_ipc, OID_AUTO, mb_wd_dump,
CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_LOCKED,
0, 0, mbuf_wd_dump_sysctl, "A", "mbuf watchdog dump");
#endif /* DEBUG || DEVELOPMENT */
SYSCTL_PROC(_kern_ipc, OID_AUTO, mleak_top_trace,
CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED,
0, 0, mleak_top_trace_sysctl, "S,mb_top_trace", "");
SYSCTL_PROC(_kern_ipc, OID_AUTO, mleak_table,
CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED,
0, 0, mleak_table_sysctl, "S,mleak_table", "");
SYSCTL_INT(_kern_ipc, OID_AUTO, mleak_sample_factor,
CTLFLAG_RW | CTLFLAG_LOCKED, &mleak_table.mleak_sample_factor, 0, "");
SYSCTL_INT(_kern_ipc, OID_AUTO, mb_normalized,
CTLFLAG_RD | CTLFLAG_LOCKED, &mb_normalized, 0, "");
SYSCTL_INT(_kern_ipc, OID_AUTO, mb_watchdog,
CTLFLAG_RW | CTLFLAG_LOCKED, &mb_watchdog, 0, "");
SYSCTL_PROC(_kern_ipc, OID_AUTO, mb_drain_force,
CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, NULL, 0,
m_drain_force_sysctl, "I",
"Forces the mbuf garbage collection to run");
SYSCTL_INT(_kern_ipc, OID_AUTO, mb_drain_maxint,
CTLFLAG_RW | CTLFLAG_LOCKED, &mb_drain_maxint, 0,
"Minimum time interval between garbage collection");