/*
* Copyright (c) 2011 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@
*/
/* A pool of threads which attempt to verify multiprocessor TLB coherency.
* Creates -t threads, by default 4
* Creates -s separate mmap(MAP_ANON) R/W mappings, sized at 1 page each but
* alterable via -z <npages>
* Initially read-faults each mapping in, verifying first-word zerofill--
* The kernel typically uses the physical aperture to perform the zerofill
* Writes map_address (page_aligned) | low 12 bits of the PID at the first word
* This can help verify ASID related inconsistencies
* Records a timestamp in a Structure associated with each mapping
* With a custom kernel, it has the option of creating a remapping of the page in
* the kernel's address space to exercise shared kernel mapping coherency.
* Each thread subsequently loops around on the set of mappings. One thread is designated
* the observer thread. The thread acquires a lock on the arena element,
* verifies that the mapping has the expected pattern (Address | PID), if the
* element is in the MAPPED state. Can optionally tell the kernel to check its
* alias as well. If it notices a mismatch, it has the option to issue a syscall
* to stop kernel tracing. If the -f option is supplied, the test is terminated.
* If the page has lingered beyond -l microseconds, non-observer threads will
* unmap the page, optionally calling into the kernel to unmap its alias, and
* repopulate the element.
* After this sequence, the thread will optionally usleep for -p microseconds,
* to allow for idle power management to engage if possible (errata might exist
* in those areas), or context switches to occur.
* Created Derek Kumar, 2011.
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/mman.h>
#include <pthread.h>
#include <string.h>
#include <mach/mach_time.h>
#include <libkern/OSAtomic.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/sysctl.h>
typedef struct {
OSSpinLock tlock;
uintptr_t taddr;
unsigned tstate;
uint64_t tctime;
} cpage;
cpage *parray;
#define ARENASIZE (1024)
#define NTHREADS (4)
#define PAGE_LINGER_TIME (2000000)
#define MAX_THREADS (512)
#define MYSYS (215)
#define CONSISTENCY(...) fprintf(stderr, __VA_ARGS__ );
unsigned arenasize = ARENASIZE, mapping_size;
uint64_t page_linger_time = PAGE_LINGER_TIME;
enum arenastates {MTOUCHED = 1, UNMAPPED = 2, MAPPED = 4, WP =8};
enum syscaction {MDOMAP = 1, MDOUNMAP = 2, MDOCHECK = 4};
enum ttypes {OBSERVER = 1, LOOPER = 2};
bool trymode = true;
bool all_stop = false;
bool stop_on_failure = false;
bool reuse_addrs = true;
bool dosyscall = false;
pid_t cpid;
int sleepus;
pthread_t threads[MAX_THREADS];
uint32_t roles[MAX_THREADS];
void
usage(char **a)
{
exit(1);
}
void
set_enable(int val)
{
int mib[6];
size_t needed;
mib[0] = CTL_KERN;
mib[1] = KERN_KDEBUG;
mib[2] = KERN_KDENABLE;
mib[3] = val;
mib[4] = 0;
mib[5] = 0;
if (sysctl(mib, 4, NULL, &needed, NULL, 0) < 0) {
printf("trace facility failure, KERN_KDENABLE\n");
}
}
void
initialize_arena_element(int i)
{
__unused int sysret;
void *hint = reuse_addrs ? (void *)0x1000 : NULL;
parray[i].taddr = (uintptr_t)mmap(hint, mapping_size, PROT_READ | PROT_WRITE, MAP_ANON | MAP_SHARED, -1, 0);
if (parray[i].taddr == (uintptr_t)MAP_FAILED) {
perror("mmap");
exit(2);
}
#if !defined(__LP64__)
uint32_t pattern = parray[i].taddr;
pattern |= cpid & 0xFFF;
// memset_pattern4((void *)parray[i].taddr, &pattern, PAGE_SIZE); //
// uncomment to fill the whole page, but a sufficiently unique first word
// gets the job done without slowing down the test
#else
uint64_t pattern = parray[i].taddr;
pattern |= (cpid & 0xFFF);
// memset_pattern8(parray[i].taddr, &pattern, PAGE_SIZE);
#endif
uint64_t val = (*(uintptr_t *)parray[i].taddr);
if (val != 0) {
CONSISTENCY("Mismatch, actual: 0x%llx, expected: 0x%llx\n", (unsigned long long)val, 0ULL);
if (stop_on_failure) {
set_enable(0);
exit(5);
}
}
for (int k = 0; k < (mapping_size >> PAGE_SHIFT); k++) {
*(uintptr_t *)(parray[i].taddr + k * PAGE_SIZE) = pattern;
}
parray[i].tctime = mach_absolute_time();
parray[i].tstate = MTOUCHED;
if (dosyscall) {
sysret = syscall(MYSYS, MDOMAP, parray[i].taddr, pattern, i, mapping_size);
}
}
void
initialize_arena(void)
{
for (int i = 0; i < arenasize; i++) {
initialize_arena_element(i);
}
}
void *
tlbexerciser(void *targs)
{
uint32_t role = *(uint32_t *)targs;
__unused int sysret;
printf("Starting thread %p, role: %u\n", pthread_self(), role);
for (;;) {
for (int i = 0; i < arenasize; i++) {
if (all_stop) {
return NULL;
}
if (trymode) {
if (OSSpinLockTry(&parray[i].tlock) == false) {
continue;
}
} else {
OSSpinLockLock(&parray[i].tlock);
}
if (parray[i].tstate != UNMAPPED) {
uintptr_t ad;
ad = parray[i].taddr | (cpid & 0xFFF);
uintptr_t val = *(uintptr_t *)parray[i].taddr;
if (val != ad) {
if (stop_on_failure) {
all_stop = true;
}
syscall(180, 0x71BC0000, (ad >> 32), (ad & ~0), 0, 0, 0);
CONSISTENCY("Mismatch, actual: 0x%llx, expected: 0x%llx\n", (unsigned long long)val, (unsigned long long)ad);
if (stop_on_failure) {
set_enable(0);
exit(5);
}
}
if (dosyscall) {
sysret = syscall(MYSYS, MDOCHECK, parray[i].taddr, ad, i, 0);
}
if ((role != OBSERVER) && ((mach_absolute_time() - parray[i].tctime) > page_linger_time)) {
parray[i].tstate = UNMAPPED;
if (munmap((void *)parray[i].taddr, mapping_size) != 0) {
perror("munmap");
}
if (dosyscall) {
sysret = syscall(MYSYS, MDOUNMAP, parray[i].taddr, ad, i, mapping_size);
}
}
} else {
if (role != OBSERVER) {
initialize_arena_element(i);
}
}
parray[i].tlock = 0; //unlock
if (sleepus) {
usleep(sleepus);
}
}
}
return NULL;
}
int
main(int argc, char **argv)
{
extern char *optarg;
int arg;
unsigned nthreads = NTHREADS;
mapping_size = PAGE_SIZE;
while ((arg = getopt(argc, argv, "l:t:h:s:p:z:fry")) != -1) {
switch (arg) {
case 'l':
page_linger_time = strtoull(optarg, NULL, 0);
break;
case 't':
nthreads = atoi(optarg);
break;
case 's':
arenasize = atoi(optarg); // we typically want this to
// be sized < 2nd level TLB
break;
case 'f':
stop_on_failure = true;
break;
case 'r':
reuse_addrs = false;
break;
case 'p':
sleepus = atoi(optarg);
break;
case 'y':
dosyscall = true;
break;
case 'z':
mapping_size = atoi(optarg) * PAGE_SIZE;
break;
case 'h':
usage(argv);
}
}
if (optind != argc) {
usage(argv);
}
printf("page_linger_time: 0x%llx, nthreads: %u, arenasize: %u sleepus: %d reuse_addrs: %u, stop_on_failure: %u, dosyscall: %u, mappingsize: 0x%x\n", page_linger_time, nthreads, arenasize, sleepus, reuse_addrs, (unsigned) stop_on_failure, dosyscall, mapping_size);
parray = calloc(arenasize, sizeof(cpage));
cpid = getpid();
initialize_arena();
for (int dex = 0; dex < nthreads; dex++) {
roles[dex] = LOOPER;
if (dex == 0) {
roles[dex] = OBSERVER;
}
int result = pthread_create(&threads[dex], NULL, tlbexerciser, &roles[dex]);
if (result) {
printf("pthread_create: %d starting worker thread; aborting.\n", result);
return result;
}
}
for (int dex = 0; dex < nthreads; dex++) {
void *rtn;
int result = pthread_join(threads[dex], &rtn);
if (result) {
printf("pthread_join(): %d, aborting\n", result);
return result;
}
if (rtn) {
printf("***Aborting on worker error\n");
exit(1);
}
}
return 0;
}