Viewing file:  tsan_rtl_thread.cpp (10.82 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
//===-- tsan_rtl_thread.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_placement_new.h"
#include "tsan_rtl.h"
#include "tsan_mman.h"
#include "tsan_platform.h"
#include "tsan_report.h"
#include "tsan_sync.h"
namespace __tsan {
// ThreadContext implementation.
ThreadContext::ThreadContext(Tid tid)
: ThreadContextBase(tid), thr(), sync(), epoch0(), epoch1() {}
#if !SANITIZER_GO
ThreadContext::~ThreadContext() {
}
#endif
void ThreadContext::OnReset() {
CHECK_EQ(sync.size(), 0);
uptr trace_p = GetThreadTrace(tid);
ReleaseMemoryPagesToOS(trace_p, trace_p + TraceSize() * sizeof(Event));
//!!! ReleaseMemoryToOS(GetThreadTraceHeader(tid), sizeof(Trace));
}
#if !SANITIZER_GO
struct ThreadLeak {
ThreadContext *tctx;
int count;
};
static void CollectThreadLeaks(ThreadContextBase *tctx_base, void *arg) {
auto &leaks = *static_cast<Vector<ThreadLeak> *>(arg);
auto *tctx = static_cast<ThreadContext *>(tctx_base);
if (tctx->detached || tctx->status != ThreadStatusFinished)
return;
for (uptr i = 0; i < leaks.Size(); i++) {
if (leaks[i].tctx->creation_stack_id == tctx->creation_stack_id) {
leaks[i].count++;
return;
}
}
leaks.PushBack({tctx, 1});
}
#endif
#if !SANITIZER_GO
static void ReportIgnoresEnabled(ThreadContext *tctx, IgnoreSet *set) {
if (tctx->tid == kMainTid) {
Printf("ThreadSanitizer: main thread finished with ignores enabled\n");
} else {
Printf("ThreadSanitizer: thread T%d %s finished with ignores enabled,"
" created at:\n", tctx->tid, tctx->name);
PrintStack(SymbolizeStackId(tctx->creation_stack_id));
}
Printf(" One of the following ignores was not ended"
" (in order of probability)\n");
for (uptr i = 0; i < set->Size(); i++) {
Printf(" Ignore was enabled at:\n");
PrintStack(SymbolizeStackId(set->At(i)));
}
Die();
}
static void ThreadCheckIgnore(ThreadState *thr) {
if (ctx->after_multithreaded_fork)
return;
if (thr->ignore_reads_and_writes)
ReportIgnoresEnabled(thr->tctx, &thr->mop_ignore_set);
if (thr->ignore_sync)
ReportIgnoresEnabled(thr->tctx, &thr->sync_ignore_set);
}
#else
static void ThreadCheckIgnore(ThreadState *thr) {}
#endif
void ThreadFinalize(ThreadState *thr) {
ThreadCheckIgnore(thr);
#if !SANITIZER_GO
if (!ShouldReport(thr, ReportTypeThreadLeak))
return;
ThreadRegistryLock l(&ctx->thread_registry);
Vector<ThreadLeak> leaks;
ctx->thread_registry.RunCallbackForEachThreadLocked(CollectThreadLeaks,
&leaks);
for (uptr i = 0; i < leaks.Size(); i++) {
ScopedReport rep(ReportTypeThreadLeak);
rep.AddThread(leaks[i].tctx, true);
rep.SetCount(leaks[i].count);
OutputReport(thr, rep);
}
#endif
}
int ThreadCount(ThreadState *thr) {
uptr result;
ctx->thread_registry.GetNumberOfThreads(0, 0, &result);
return (int)result;
}
struct OnCreatedArgs {
ThreadState *thr;
uptr pc;
};
Tid ThreadCreate(ThreadState *thr, uptr pc, uptr uid, bool detached) {
OnCreatedArgs args = { thr, pc };
u32 parent_tid = thr ? thr->tid : kInvalidTid; // No parent for GCD workers.
Tid tid = ctx->thread_registry.CreateThread(uid, detached, parent_tid, &args);
DPrintf("#%d: ThreadCreate tid=%d uid=%zu\n", parent_tid, tid, uid);
return tid;
}
void ThreadContext::OnCreated(void *arg) {
thr = 0;
if (tid == kMainTid)
return;
OnCreatedArgs *args = static_cast<OnCreatedArgs *>(arg);
if (!args->thr) // GCD workers don't have a parent thread.
return;
args->thr->fast_state.IncrementEpoch();
// Can't increment epoch w/o writing to the trace as well.
TraceAddEvent(args->thr, args->thr->fast_state, EventTypeMop, 0);
ReleaseImpl(args->thr, 0, &sync);
creation_stack_id = CurrentStackId(args->thr, args->pc);
}
extern "C" void __tsan_stack_initialization() {}
struct OnStartedArgs {
ThreadState *thr;
uptr stk_addr;
uptr stk_size;
uptr tls_addr;
uptr tls_size;
};
void ThreadStart(ThreadState *thr, Tid tid, tid_t os_id,
ThreadType thread_type) {
uptr stk_addr = 0;
uptr stk_size = 0;
uptr tls_addr = 0;
uptr tls_size = 0;
#if !SANITIZER_GO
if (thread_type != ThreadType::Fiber)
GetThreadStackAndTls(tid == kMainTid, &stk_addr, &stk_size, &tls_addr,
&tls_size);
#endif
ThreadRegistry *tr = &ctx->thread_registry;
OnStartedArgs args = { thr, stk_addr, stk_size, tls_addr, tls_size };
tr->StartThread(tid, os_id, thread_type, &args);
while (!thr->tctx->trace.parts.Empty()) thr->tctx->trace.parts.PopBack();
#if !SANITIZER_GO
if (ctx->after_multithreaded_fork) {
thr->ignore_interceptors++;
ThreadIgnoreBegin(thr, 0);
ThreadIgnoreSyncBegin(thr, 0);
}
#endif
#if !SANITIZER_GO
// Don't imitate stack/TLS writes for the main thread,
// because its initialization is synchronized with all
// subsequent threads anyway.
if (tid != kMainTid) {
if (stk_addr && stk_size) {
const uptr pc = StackTrace::GetNextInstructionPc(
reinterpret_cast<uptr>(__tsan_stack_initialization));
MemoryRangeImitateWrite(thr, pc, stk_addr, stk_size);
}
if (tls_addr && tls_size)
ImitateTlsWrite(thr, tls_addr, tls_size);
}
#endif
}
void ThreadContext::OnStarted(void *arg) {
OnStartedArgs *args = static_cast<OnStartedArgs *>(arg);
thr = args->thr;
// RoundUp so that one trace part does not contain events
// from different threads.
epoch0 = RoundUp(epoch1 + 1, kTracePartSize);
epoch1 = (u64)-1;
new (thr)
ThreadState(ctx, tid, unique_id, epoch0, reuse_count, args->stk_addr,
args->stk_size, args->tls_addr, args->tls_size);
if (common_flags()->detect_deadlocks)
thr->dd_lt = ctx->dd->CreateLogicalThread(unique_id);
thr->fast_state.SetHistorySize(flags()->history_size);
// Commit switch to the new part of the trace.
// TraceAddEvent will reset stack0/mset0 in the new part for us.
TraceAddEvent(thr, thr->fast_state, EventTypeMop, 0);
thr->fast_synch_epoch = epoch0;
AcquireImpl(thr, 0, &sync);
sync.Reset(&thr->proc()->clock_cache);
thr->tctx = this;
thr->is_inited = true;
DPrintf(
"#%d: ThreadStart epoch=%zu stk_addr=%zx stk_size=%zx "
"tls_addr=%zx tls_size=%zx\n",
tid, (uptr)epoch0, args->stk_addr, args->stk_size, args->tls_addr,
args->tls_size);
}
void ThreadFinish(ThreadState *thr) {
ThreadCheckIgnore(thr);
if (thr->stk_addr && thr->stk_size)
DontNeedShadowFor(thr->stk_addr, thr->stk_size);
if (thr->tls_addr && thr->tls_size)
DontNeedShadowFor(thr->tls_addr, thr->tls_size);
thr->is_dead = true;
ctx->thread_registry.FinishThread(thr->tid);
}
void ThreadContext::OnFinished() {
#if SANITIZER_GO
Free(thr->shadow_stack);
thr->shadow_stack_pos = nullptr;
thr->shadow_stack_end = nullptr;
#endif
if (!detached) {
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, 0, &sync);
}
epoch1 = thr->fast_state.epoch();
if (common_flags()->detect_deadlocks)
ctx->dd->DestroyLogicalThread(thr->dd_lt);
thr->clock.ResetCached(&thr->proc()->clock_cache);
#if !SANITIZER_GO
thr->last_sleep_clock.ResetCached(&thr->proc()->clock_cache);
#endif
#if !SANITIZER_GO
PlatformCleanUpThreadState(thr);
#endif
thr->~ThreadState();
thr = 0;
}
struct ConsumeThreadContext {
uptr uid;
ThreadContextBase *tctx;
};
static bool ConsumeThreadByUid(ThreadContextBase *tctx, void *arg) {
ConsumeThreadContext *findCtx = (ConsumeThreadContext *)arg;
if (tctx->user_id == findCtx->uid && tctx->status != ThreadStatusInvalid) {
if (findCtx->tctx) {
// Ensure that user_id is unique. If it's not the case we are screwed.
// Something went wrong before, but now there is no way to recover.
// Returning a wrong thread is not an option, it may lead to very hard
// to debug false positives (e.g. if we join a wrong thread).
Report("ThreadSanitizer: dup thread with used id 0x%zx\n", findCtx->uid);
Die();
}
findCtx->tctx = tctx;
tctx->user_id = 0;
}
return false;
}
Tid ThreadConsumeTid(ThreadState *thr, uptr pc, uptr uid) {
ConsumeThreadContext findCtx = {uid, nullptr};
ctx->thread_registry.FindThread(ConsumeThreadByUid, &findCtx);
Tid tid = findCtx.tctx ? findCtx.tctx->tid : kInvalidTid;
DPrintf("#%d: ThreadTid uid=%zu tid=%d\n", thr->tid, uid, tid);
return tid;
}
void ThreadJoin(ThreadState *thr, uptr pc, Tid tid) {
CHECK_GT(tid, 0);
CHECK_LT(tid, kMaxTid);
DPrintf("#%d: ThreadJoin tid=%d\n", thr->tid, tid);
ctx->thread_registry.JoinThread(tid, thr);
}
void ThreadContext::OnJoined(void *arg) {
ThreadState *caller_thr = static_cast<ThreadState *>(arg);
AcquireImpl(caller_thr, 0, &sync);
sync.Reset(&caller_thr->proc()->clock_cache);
}
void ThreadContext::OnDead() { CHECK_EQ(sync.size(), 0); }
void ThreadDetach(ThreadState *thr, uptr pc, Tid tid) {
CHECK_GT(tid, 0);
CHECK_LT(tid, kMaxTid);
ctx->thread_registry.DetachThread(tid, thr);
}
void ThreadContext::OnDetached(void *arg) {
ThreadState *thr1 = static_cast<ThreadState *>(arg);
sync.Reset(&thr1->proc()->clock_cache);
}
void ThreadNotJoined(ThreadState *thr, uptr pc, Tid tid, uptr uid) {
CHECK_GT(tid, 0);
CHECK_LT(tid, kMaxTid);
ctx->thread_registry.SetThreadUserId(tid, uid);
}
void ThreadSetName(ThreadState *thr, const char *name) {
ctx->thread_registry.SetThreadName(thr->tid, name);
}
#if !SANITIZER_GO
void FiberSwitchImpl(ThreadState *from, ThreadState *to) {
Processor *proc = from->proc();
ProcUnwire(proc, from);
ProcWire(proc, to);
set_cur_thread(to);
}
ThreadState *FiberCreate(ThreadState *thr, uptr pc, unsigned flags) {
void *mem = Alloc(sizeof(ThreadState));
ThreadState *fiber = static_cast<ThreadState *>(mem);
internal_memset(fiber, 0, sizeof(*fiber));
Tid tid = ThreadCreate(thr, pc, 0, true);
FiberSwitchImpl(thr, fiber);
ThreadStart(fiber, tid, 0, ThreadType::Fiber);
FiberSwitchImpl(fiber, thr);
return fiber;
}
void FiberDestroy(ThreadState *thr, uptr pc, ThreadState *fiber) {
FiberSwitchImpl(thr, fiber);
ThreadFinish(fiber);
FiberSwitchImpl(fiber, thr);
Free(fiber);
}
void FiberSwitch(ThreadState *thr, uptr pc,
ThreadState *fiber, unsigned flags) {
if (!(flags & FiberSwitchFlagNoSync))
Release(thr, pc, (uptr)fiber);
FiberSwitchImpl(thr, fiber);
if (!(flags & FiberSwitchFlagNoSync))
Acquire(fiber, pc, (uptr)fiber);
}
#endif
} // namespace __tsan
|
