zig/lib/tsan/tsan_rtl_mutex.cpp

548 lines
19 KiB
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//===-- tsan_rtl_mutex.cpp ------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file is a part of ThreadSanitizer (TSan), a race detector.
//
//===----------------------------------------------------------------------===//
#include <sanitizer_common/sanitizer_deadlock_detector_interface.h>
#include <sanitizer_common/sanitizer_stackdepot.h>
#include "tsan_rtl.h"
#include "tsan_flags.h"
#include "tsan_sync.h"
#include "tsan_report.h"
#include "tsan_symbolize.h"
#include "tsan_platform.h"
namespace __tsan {
void ReportDeadlock(ThreadState *thr, uptr pc, DDReport *r);
struct Callback final : public DDCallback {
ThreadState *thr;
uptr pc;
Callback(ThreadState *thr, uptr pc)
: thr(thr)
, pc(pc) {
DDCallback::pt = thr->proc()->dd_pt;
DDCallback::lt = thr->dd_lt;
}
u32 Unwind() override { return CurrentStackId(thr, pc); }
int UniqueTid() override { return thr->unique_id; }
};
void DDMutexInit(ThreadState *thr, uptr pc, SyncVar *s) {
Callback cb(thr, pc);
ctx->dd->MutexInit(&cb, &s->dd);
s->dd.ctx = s->GetId();
}
static void ReportMutexMisuse(ThreadState *thr, uptr pc, ReportType typ,
uptr addr, u64 mid) {
// In Go, these misuses are either impossible, or detected by std lib,
// or false positives (e.g. unlock in a different thread).
if (SANITIZER_GO)
return;
if (!ShouldReport(thr, typ))
return;
ThreadRegistryLock l(ctx->thread_registry);
ScopedReport rep(typ);
rep.AddMutex(mid);
VarSizeStackTrace trace;
ObtainCurrentStack(thr, pc, &trace);
rep.AddStack(trace, true);
rep.AddLocation(addr, 1);
OutputReport(thr, rep);
}
void MutexCreate(ThreadState *thr, uptr pc, uptr addr, u32 flagz) NO_THREAD_SAFETY_ANALYSIS {
DPrintf("#%d: MutexCreate %zx flagz=0x%x\n", thr->tid, addr, flagz);
if (!(flagz & MutexFlagLinkerInit) && IsAppMem(addr)) {
CHECK(!thr->is_freeing);
thr->is_freeing = true;
MemoryWrite(thr, pc, addr, kSizeLog1);
thr->is_freeing = false;
}
SyncVar *s = ctx->metamap.GetOrCreateAndLock(thr, pc, addr, true);
s->SetFlags(flagz & MutexCreationFlagMask);
if (!SANITIZER_GO && s->creation_stack_id == 0)
s->creation_stack_id = CurrentStackId(thr, pc);
s->mtx.Unlock();
}
void MutexDestroy(ThreadState *thr, uptr pc, uptr addr, u32 flagz) NO_THREAD_SAFETY_ANALYSIS {
DPrintf("#%d: MutexDestroy %zx\n", thr->tid, addr);
SyncVar *s = ctx->metamap.GetIfExistsAndLock(addr, true);
if (s == 0)
return;
if ((flagz & MutexFlagLinkerInit)
|| s->IsFlagSet(MutexFlagLinkerInit)
|| ((flagz & MutexFlagNotStatic) && !s->IsFlagSet(MutexFlagNotStatic))) {
// Destroy is no-op for linker-initialized mutexes.
s->mtx.Unlock();
return;
}
if (common_flags()->detect_deadlocks) {
Callback cb(thr, pc);
ctx->dd->MutexDestroy(&cb, &s->dd);
ctx->dd->MutexInit(&cb, &s->dd);
}
bool unlock_locked = false;
if (flags()->report_destroy_locked && s->owner_tid != kInvalidTid &&
!s->IsFlagSet(MutexFlagBroken)) {
s->SetFlags(MutexFlagBroken);
unlock_locked = true;
}
u64 mid = s->GetId();
u64 last_lock = s->last_lock;
if (!unlock_locked)
s->Reset(thr->proc()); // must not reset it before the report is printed
s->mtx.Unlock();
if (unlock_locked && ShouldReport(thr, ReportTypeMutexDestroyLocked)) {
ThreadRegistryLock l(ctx->thread_registry);
ScopedReport rep(ReportTypeMutexDestroyLocked);
rep.AddMutex(mid);
VarSizeStackTrace trace;
ObtainCurrentStack(thr, pc, &trace);
rep.AddStack(trace, true);
FastState last(last_lock);
RestoreStack(last.tid(), last.epoch(), &trace, 0);
rep.AddStack(trace, true);
rep.AddLocation(addr, 1);
OutputReport(thr, rep);
SyncVar *s = ctx->metamap.GetIfExistsAndLock(addr, true);
if (s != 0) {
s->Reset(thr->proc());
s->mtx.Unlock();
}
}
thr->mset.Remove(mid);
// Imitate a memory write to catch unlock-destroy races.
// Do this outside of sync mutex, because it can report a race which locks
// sync mutexes.
if (IsAppMem(addr)) {
CHECK(!thr->is_freeing);
thr->is_freeing = true;
MemoryWrite(thr, pc, addr, kSizeLog1);
thr->is_freeing = false;
}
// s will be destroyed and freed in MetaMap::FreeBlock.
}
void MutexPreLock(ThreadState *thr, uptr pc, uptr addr, u32 flagz) NO_THREAD_SAFETY_ANALYSIS {
DPrintf("#%d: MutexPreLock %zx flagz=0x%x\n", thr->tid, addr, flagz);
if (!(flagz & MutexFlagTryLock) && common_flags()->detect_deadlocks) {
SyncVar *s = ctx->metamap.GetOrCreateAndLock(thr, pc, addr, false);
s->UpdateFlags(flagz);
if (s->owner_tid != thr->tid) {
Callback cb(thr, pc);
ctx->dd->MutexBeforeLock(&cb, &s->dd, true);
s->mtx.ReadUnlock();
ReportDeadlock(thr, pc, ctx->dd->GetReport(&cb));
} else {
s->mtx.ReadUnlock();
}
}
}
void MutexPostLock(ThreadState *thr, uptr pc, uptr addr, u32 flagz,
int rec) NO_THREAD_SAFETY_ANALYSIS {
DPrintf("#%d: MutexPostLock %zx flag=0x%x rec=%d\n",
thr->tid, addr, flagz, rec);
if (flagz & MutexFlagRecursiveLock)
CHECK_GT(rec, 0);
else
rec = 1;
if (IsAppMem(addr))
MemoryReadAtomic(thr, pc, addr, kSizeLog1);
SyncVar *s = ctx->metamap.GetOrCreateAndLock(thr, pc, addr, true);
s->UpdateFlags(flagz);
thr->fast_state.IncrementEpoch();
TraceAddEvent(thr, thr->fast_state, EventTypeLock, s->GetId());
bool report_double_lock = false;
if (s->owner_tid == kInvalidTid) {
CHECK_EQ(s->recursion, 0);
s->owner_tid = thr->tid;
s->last_lock = thr->fast_state.raw();
} else if (s->owner_tid == thr->tid) {
CHECK_GT(s->recursion, 0);
} else if (flags()->report_mutex_bugs && !s->IsFlagSet(MutexFlagBroken)) {
s->SetFlags(MutexFlagBroken);
report_double_lock = true;
}
const bool first = s->recursion == 0;
s->recursion += rec;
if (first) {
AcquireImpl(thr, pc, &s->clock);
AcquireImpl(thr, pc, &s->read_clock);
} else if (!s->IsFlagSet(MutexFlagWriteReentrant)) {
}
thr->mset.Add(s->GetId(), true, thr->fast_state.epoch());
bool pre_lock = false;
if (first && common_flags()->detect_deadlocks) {
pre_lock = (flagz & MutexFlagDoPreLockOnPostLock) &&
!(flagz & MutexFlagTryLock);
Callback cb(thr, pc);
if (pre_lock)
ctx->dd->MutexBeforeLock(&cb, &s->dd, true);
ctx->dd->MutexAfterLock(&cb, &s->dd, true, flagz & MutexFlagTryLock);
}
u64 mid = s->GetId();
s->mtx.Unlock();
// Can't touch s after this point.
s = 0;
if (report_double_lock)
ReportMutexMisuse(thr, pc, ReportTypeMutexDoubleLock, addr, mid);
if (first && pre_lock && common_flags()->detect_deadlocks) {
Callback cb(thr, pc);
ReportDeadlock(thr, pc, ctx->dd->GetReport(&cb));
}
}
int MutexUnlock(ThreadState *thr, uptr pc, uptr addr, u32 flagz) NO_THREAD_SAFETY_ANALYSIS {
DPrintf("#%d: MutexUnlock %zx flagz=0x%x\n", thr->tid, addr, flagz);
if (IsAppMem(addr))
MemoryReadAtomic(thr, pc, addr, kSizeLog1);
SyncVar *s = ctx->metamap.GetOrCreateAndLock(thr, pc, addr, true);
thr->fast_state.IncrementEpoch();
TraceAddEvent(thr, thr->fast_state, EventTypeUnlock, s->GetId());
int rec = 0;
bool report_bad_unlock = false;
if (!SANITIZER_GO && (s->recursion == 0 || s->owner_tid != thr->tid)) {
if (flags()->report_mutex_bugs && !s->IsFlagSet(MutexFlagBroken)) {
s->SetFlags(MutexFlagBroken);
report_bad_unlock = true;
}
} else {
rec = (flagz & MutexFlagRecursiveUnlock) ? s->recursion : 1;
s->recursion -= rec;
if (s->recursion == 0) {
s->owner_tid = kInvalidTid;
ReleaseStoreImpl(thr, pc, &s->clock);
} else {
}
}
thr->mset.Del(s->GetId(), true);
if (common_flags()->detect_deadlocks && s->recursion == 0 &&
!report_bad_unlock) {
Callback cb(thr, pc);
ctx->dd->MutexBeforeUnlock(&cb, &s->dd, true);
}
u64 mid = s->GetId();
s->mtx.Unlock();
// Can't touch s after this point.
if (report_bad_unlock)
ReportMutexMisuse(thr, pc, ReportTypeMutexBadUnlock, addr, mid);
if (common_flags()->detect_deadlocks && !report_bad_unlock) {
Callback cb(thr, pc);
ReportDeadlock(thr, pc, ctx->dd->GetReport(&cb));
}
return rec;
}
void MutexPreReadLock(ThreadState *thr, uptr pc, uptr addr, u32 flagz) NO_THREAD_SAFETY_ANALYSIS {
DPrintf("#%d: MutexPreReadLock %zx flagz=0x%x\n", thr->tid, addr, flagz);
if (!(flagz & MutexFlagTryLock) && common_flags()->detect_deadlocks) {
SyncVar *s = ctx->metamap.GetOrCreateAndLock(thr, pc, addr, false);
s->UpdateFlags(flagz);
Callback cb(thr, pc);
ctx->dd->MutexBeforeLock(&cb, &s->dd, false);
s->mtx.ReadUnlock();
ReportDeadlock(thr, pc, ctx->dd->GetReport(&cb));
}
}
void MutexPostReadLock(ThreadState *thr, uptr pc, uptr addr, u32 flagz) NO_THREAD_SAFETY_ANALYSIS {
DPrintf("#%d: MutexPostReadLock %zx flagz=0x%x\n", thr->tid, addr, flagz);
if (IsAppMem(addr))
MemoryReadAtomic(thr, pc, addr, kSizeLog1);
SyncVar *s = ctx->metamap.GetOrCreateAndLock(thr, pc, addr, false);
s->UpdateFlags(flagz);
thr->fast_state.IncrementEpoch();
TraceAddEvent(thr, thr->fast_state, EventTypeRLock, s->GetId());
bool report_bad_lock = false;
if (s->owner_tid != kInvalidTid) {
if (flags()->report_mutex_bugs && !s->IsFlagSet(MutexFlagBroken)) {
s->SetFlags(MutexFlagBroken);
report_bad_lock = true;
}
}
AcquireImpl(thr, pc, &s->clock);
s->last_lock = thr->fast_state.raw();
thr->mset.Add(s->GetId(), false, thr->fast_state.epoch());
bool pre_lock = false;
if (common_flags()->detect_deadlocks) {
pre_lock = (flagz & MutexFlagDoPreLockOnPostLock) &&
!(flagz & MutexFlagTryLock);
Callback cb(thr, pc);
if (pre_lock)
ctx->dd->MutexBeforeLock(&cb, &s->dd, false);
ctx->dd->MutexAfterLock(&cb, &s->dd, false, flagz & MutexFlagTryLock);
}
u64 mid = s->GetId();
s->mtx.ReadUnlock();
// Can't touch s after this point.
s = 0;
if (report_bad_lock)
ReportMutexMisuse(thr, pc, ReportTypeMutexBadReadLock, addr, mid);
if (pre_lock && common_flags()->detect_deadlocks) {
Callback cb(thr, pc);
ReportDeadlock(thr, pc, ctx->dd->GetReport(&cb));
}
}
void MutexReadUnlock(ThreadState *thr, uptr pc, uptr addr) NO_THREAD_SAFETY_ANALYSIS {
DPrintf("#%d: MutexReadUnlock %zx\n", thr->tid, addr);
if (IsAppMem(addr))
MemoryReadAtomic(thr, pc, addr, kSizeLog1);
SyncVar *s = ctx->metamap.GetOrCreateAndLock(thr, pc, addr, true);
thr->fast_state.IncrementEpoch();
TraceAddEvent(thr, thr->fast_state, EventTypeRUnlock, s->GetId());
bool report_bad_unlock = false;
if (s->owner_tid != kInvalidTid) {
if (flags()->report_mutex_bugs && !s->IsFlagSet(MutexFlagBroken)) {
s->SetFlags(MutexFlagBroken);
report_bad_unlock = true;
}
}
ReleaseImpl(thr, pc, &s->read_clock);
if (common_flags()->detect_deadlocks && s->recursion == 0) {
Callback cb(thr, pc);
ctx->dd->MutexBeforeUnlock(&cb, &s->dd, false);
}
u64 mid = s->GetId();
s->mtx.Unlock();
// Can't touch s after this point.
thr->mset.Del(mid, false);
if (report_bad_unlock)
ReportMutexMisuse(thr, pc, ReportTypeMutexBadReadUnlock, addr, mid);
if (common_flags()->detect_deadlocks) {
Callback cb(thr, pc);
ReportDeadlock(thr, pc, ctx->dd->GetReport(&cb));
}
}
void MutexReadOrWriteUnlock(ThreadState *thr, uptr pc, uptr addr) NO_THREAD_SAFETY_ANALYSIS {
DPrintf("#%d: MutexReadOrWriteUnlock %zx\n", thr->tid, addr);
if (IsAppMem(addr))
MemoryReadAtomic(thr, pc, addr, kSizeLog1);
SyncVar *s = ctx->metamap.GetOrCreateAndLock(thr, pc, addr, true);
bool write = true;
bool report_bad_unlock = false;
if (s->owner_tid == kInvalidTid) {
// Seems to be read unlock.
write = false;
thr->fast_state.IncrementEpoch();
TraceAddEvent(thr, thr->fast_state, EventTypeRUnlock, s->GetId());
ReleaseImpl(thr, pc, &s->read_clock);
} else if (s->owner_tid == thr->tid) {
// Seems to be write unlock.
thr->fast_state.IncrementEpoch();
TraceAddEvent(thr, thr->fast_state, EventTypeUnlock, s->GetId());
CHECK_GT(s->recursion, 0);
s->recursion--;
if (s->recursion == 0) {
s->owner_tid = kInvalidTid;
ReleaseStoreImpl(thr, pc, &s->clock);
} else {
}
} else if (!s->IsFlagSet(MutexFlagBroken)) {
s->SetFlags(MutexFlagBroken);
report_bad_unlock = true;
}
thr->mset.Del(s->GetId(), write);
if (common_flags()->detect_deadlocks && s->recursion == 0) {
Callback cb(thr, pc);
ctx->dd->MutexBeforeUnlock(&cb, &s->dd, write);
}
u64 mid = s->GetId();
s->mtx.Unlock();
// Can't touch s after this point.
if (report_bad_unlock)
ReportMutexMisuse(thr, pc, ReportTypeMutexBadUnlock, addr, mid);
if (common_flags()->detect_deadlocks) {
Callback cb(thr, pc);
ReportDeadlock(thr, pc, ctx->dd->GetReport(&cb));
}
}
void MutexRepair(ThreadState *thr, uptr pc, uptr addr) NO_THREAD_SAFETY_ANALYSIS {
DPrintf("#%d: MutexRepair %zx\n", thr->tid, addr);
SyncVar *s = ctx->metamap.GetOrCreateAndLock(thr, pc, addr, true);
s->owner_tid = kInvalidTid;
s->recursion = 0;
s->mtx.Unlock();
}
void MutexInvalidAccess(ThreadState *thr, uptr pc, uptr addr) NO_THREAD_SAFETY_ANALYSIS {
DPrintf("#%d: MutexInvalidAccess %zx\n", thr->tid, addr);
SyncVar *s = ctx->metamap.GetOrCreateAndLock(thr, pc, addr, true);
u64 mid = s->GetId();
s->mtx.Unlock();
ReportMutexMisuse(thr, pc, ReportTypeMutexInvalidAccess, addr, mid);
}
void Acquire(ThreadState *thr, uptr pc, uptr addr) NO_THREAD_SAFETY_ANALYSIS {
DPrintf("#%d: Acquire %zx\n", thr->tid, addr);
if (thr->ignore_sync)
return;
SyncVar *s = ctx->metamap.GetIfExistsAndLock(addr, false);
if (!s)
return;
AcquireImpl(thr, pc, &s->clock);
s->mtx.ReadUnlock();
}
static void UpdateClockCallback(ThreadContextBase *tctx_base, void *arg) {
ThreadState *thr = reinterpret_cast<ThreadState*>(arg);
ThreadContext *tctx = static_cast<ThreadContext*>(tctx_base);
u64 epoch = tctx->epoch1;
if (tctx->status == ThreadStatusRunning) {
epoch = tctx->thr->fast_state.epoch();
tctx->thr->clock.NoteGlobalAcquire(epoch);
}
thr->clock.set(&thr->proc()->clock_cache, tctx->tid, epoch);
}
void AcquireGlobal(ThreadState *thr, uptr pc) {
DPrintf("#%d: AcquireGlobal\n", thr->tid);
if (thr->ignore_sync)
return;
ThreadRegistryLock l(ctx->thread_registry);
ctx->thread_registry->RunCallbackForEachThreadLocked(
UpdateClockCallback, thr);
}
void ReleaseStoreAcquire(ThreadState *thr, uptr pc, uptr addr) NO_THREAD_SAFETY_ANALYSIS {
DPrintf("#%d: ReleaseStoreAcquire %zx\n", thr->tid, addr);
if (thr->ignore_sync)
return;
SyncVar *s = ctx->metamap.GetOrCreateAndLock(thr, pc, addr, true);
thr->fast_state.IncrementEpoch();
// Can't increment epoch w/o writing to the trace as well.
TraceAddEvent(thr, thr->fast_state, EventTypeMop, 0);
ReleaseStoreAcquireImpl(thr, pc, &s->clock);
s->mtx.Unlock();
}
void Release(ThreadState *thr, uptr pc, uptr addr) NO_THREAD_SAFETY_ANALYSIS {
DPrintf("#%d: Release %zx\n", thr->tid, addr);
if (thr->ignore_sync)
return;
SyncVar *s = ctx->metamap.GetOrCreateAndLock(thr, pc, addr, true);
thr->fast_state.IncrementEpoch();
// Can't increment epoch w/o writing to the trace as well.
TraceAddEvent(thr, thr->fast_state, EventTypeMop, 0);
ReleaseImpl(thr, pc, &s->clock);
s->mtx.Unlock();
}
void ReleaseStore(ThreadState *thr, uptr pc, uptr addr) NO_THREAD_SAFETY_ANALYSIS {
DPrintf("#%d: ReleaseStore %zx\n", thr->tid, addr);
if (thr->ignore_sync)
return;
SyncVar *s = ctx->metamap.GetOrCreateAndLock(thr, pc, addr, true);
thr->fast_state.IncrementEpoch();
// Can't increment epoch w/o writing to the trace as well.
TraceAddEvent(thr, thr->fast_state, EventTypeMop, 0);
ReleaseStoreImpl(thr, pc, &s->clock);
s->mtx.Unlock();
}
#if !SANITIZER_GO
static void UpdateSleepClockCallback(ThreadContextBase *tctx_base, void *arg) {
ThreadState *thr = reinterpret_cast<ThreadState*>(arg);
ThreadContext *tctx = static_cast<ThreadContext*>(tctx_base);
u64 epoch = tctx->epoch1;
if (tctx->status == ThreadStatusRunning)
epoch = tctx->thr->fast_state.epoch();
thr->last_sleep_clock.set(&thr->proc()->clock_cache, tctx->tid, epoch);
}
void AfterSleep(ThreadState *thr, uptr pc) {
DPrintf("#%d: AfterSleep %zx\n", thr->tid);
if (thr->ignore_sync)
return;
thr->last_sleep_stack_id = CurrentStackId(thr, pc);
ThreadRegistryLock l(ctx->thread_registry);
ctx->thread_registry->RunCallbackForEachThreadLocked(
UpdateSleepClockCallback, thr);
}
#endif
void AcquireImpl(ThreadState *thr, uptr pc, SyncClock *c) {
if (thr->ignore_sync)
return;
thr->clock.set(thr->fast_state.epoch());
thr->clock.acquire(&thr->proc()->clock_cache, c);
}
void ReleaseStoreAcquireImpl(ThreadState *thr, uptr pc, SyncClock *c) {
if (thr->ignore_sync)
return;
thr->clock.set(thr->fast_state.epoch());
thr->fast_synch_epoch = thr->fast_state.epoch();
thr->clock.releaseStoreAcquire(&thr->proc()->clock_cache, c);
}
void ReleaseImpl(ThreadState *thr, uptr pc, SyncClock *c) {
if (thr->ignore_sync)
return;
thr->clock.set(thr->fast_state.epoch());
thr->fast_synch_epoch = thr->fast_state.epoch();
thr->clock.release(&thr->proc()->clock_cache, c);
}
void ReleaseStoreImpl(ThreadState *thr, uptr pc, SyncClock *c) {
if (thr->ignore_sync)
return;
thr->clock.set(thr->fast_state.epoch());
thr->fast_synch_epoch = thr->fast_state.epoch();
thr->clock.ReleaseStore(&thr->proc()->clock_cache, c);
}
void AcquireReleaseImpl(ThreadState *thr, uptr pc, SyncClock *c) {
if (thr->ignore_sync)
return;
thr->clock.set(thr->fast_state.epoch());
thr->fast_synch_epoch = thr->fast_state.epoch();
thr->clock.acq_rel(&thr->proc()->clock_cache, c);
}
void ReportDeadlock(ThreadState *thr, uptr pc, DDReport *r) {
if (r == 0 || !ShouldReport(thr, ReportTypeDeadlock))
return;
ThreadRegistryLock l(ctx->thread_registry);
ScopedReport rep(ReportTypeDeadlock);
for (int i = 0; i < r->n; i++) {
rep.AddMutex(r->loop[i].mtx_ctx0);
rep.AddUniqueTid((int)r->loop[i].thr_ctx);
rep.AddThread((int)r->loop[i].thr_ctx);
}
uptr dummy_pc = 0x42;
for (int i = 0; i < r->n; i++) {
for (int j = 0; j < (flags()->second_deadlock_stack ? 2 : 1); j++) {
u32 stk = r->loop[i].stk[j];
if (stk && stk != 0xffffffff) {
rep.AddStack(StackDepotGet(stk), true);
} else {
// Sometimes we fail to extract the stack trace (FIXME: investigate),
// but we should still produce some stack trace in the report.
rep.AddStack(StackTrace(&dummy_pc, 1), true);
}
}
}
OutputReport(thr, rep);
}
} // namespace __tsan