diff options
Diffstat (limited to 'compiler-rt/lib/sanitizer_common/sanitizer_thread_registry.cpp')
| -rw-r--r-- | compiler-rt/lib/sanitizer_common/sanitizer_thread_registry.cpp | 351 |
1 files changed, 351 insertions, 0 deletions
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_thread_registry.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_thread_registry.cpp new file mode 100644 index 000000000000..f2c6f2799315 --- /dev/null +++ b/compiler-rt/lib/sanitizer_common/sanitizer_thread_registry.cpp @@ -0,0 +1,351 @@ +//===-- sanitizer_thread_registry.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 shared between sanitizer tools. +// +// General thread bookkeeping functionality. +//===----------------------------------------------------------------------===// + +#include "sanitizer_thread_registry.h" + +namespace __sanitizer { + +ThreadContextBase::ThreadContextBase(u32 tid) + : tid(tid), unique_id(0), reuse_count(), os_id(0), user_id(0), + status(ThreadStatusInvalid), detached(false), + thread_type(ThreadType::Regular), parent_tid(0), next(0) { + name[0] = '\0'; + atomic_store(&thread_destroyed, 0, memory_order_release); +} + +ThreadContextBase::~ThreadContextBase() { + // ThreadContextBase should never be deleted. + CHECK(0); +} + +void ThreadContextBase::SetName(const char *new_name) { + name[0] = '\0'; + if (new_name) { + internal_strncpy(name, new_name, sizeof(name)); + name[sizeof(name) - 1] = '\0'; + } +} + +void ThreadContextBase::SetDead() { + CHECK(status == ThreadStatusRunning || + status == ThreadStatusFinished); + status = ThreadStatusDead; + user_id = 0; + OnDead(); +} + +void ThreadContextBase::SetDestroyed() { + atomic_store(&thread_destroyed, 1, memory_order_release); +} + +bool ThreadContextBase::GetDestroyed() { + return !!atomic_load(&thread_destroyed, memory_order_acquire); +} + +void ThreadContextBase::SetJoined(void *arg) { + // FIXME(dvyukov): print message and continue (it's user error). + CHECK_EQ(false, detached); + CHECK_EQ(ThreadStatusFinished, status); + status = ThreadStatusDead; + user_id = 0; + OnJoined(arg); +} + +void ThreadContextBase::SetFinished() { + // ThreadRegistry::FinishThread calls here in ThreadStatusCreated state + // for a thread that never actually started. In that case the thread + // should go to ThreadStatusFinished regardless of whether it was created + // as detached. + if (!detached || status == ThreadStatusCreated) status = ThreadStatusFinished; + OnFinished(); +} + +void ThreadContextBase::SetStarted(tid_t _os_id, ThreadType _thread_type, + void *arg) { + status = ThreadStatusRunning; + os_id = _os_id; + thread_type = _thread_type; + OnStarted(arg); +} + +void ThreadContextBase::SetCreated(uptr _user_id, u64 _unique_id, + bool _detached, u32 _parent_tid, void *arg) { + status = ThreadStatusCreated; + user_id = _user_id; + unique_id = _unique_id; + detached = _detached; + // Parent tid makes no sense for the main thread. + if (tid != 0) + parent_tid = _parent_tid; + OnCreated(arg); +} + +void ThreadContextBase::Reset() { + status = ThreadStatusInvalid; + SetName(0); + atomic_store(&thread_destroyed, 0, memory_order_release); + OnReset(); +} + +// ThreadRegistry implementation. + +const u32 ThreadRegistry::kUnknownTid = ~0U; + +ThreadRegistry::ThreadRegistry(ThreadContextFactory factory, u32 max_threads, + u32 thread_quarantine_size, u32 max_reuse) + : context_factory_(factory), + max_threads_(max_threads), + thread_quarantine_size_(thread_quarantine_size), + max_reuse_(max_reuse), + mtx_(), + n_contexts_(0), + total_threads_(0), + alive_threads_(0), + max_alive_threads_(0), + running_threads_(0) { + threads_ = (ThreadContextBase **)MmapOrDie(max_threads_ * sizeof(threads_[0]), + "ThreadRegistry"); + dead_threads_.clear(); + invalid_threads_.clear(); +} + +void ThreadRegistry::GetNumberOfThreads(uptr *total, uptr *running, + uptr *alive) { + BlockingMutexLock l(&mtx_); + if (total) *total = n_contexts_; + if (running) *running = running_threads_; + if (alive) *alive = alive_threads_; +} + +uptr ThreadRegistry::GetMaxAliveThreads() { + BlockingMutexLock l(&mtx_); + return max_alive_threads_; +} + +u32 ThreadRegistry::CreateThread(uptr user_id, bool detached, u32 parent_tid, + void *arg) { + BlockingMutexLock l(&mtx_); + u32 tid = kUnknownTid; + ThreadContextBase *tctx = QuarantinePop(); + if (tctx) { + tid = tctx->tid; + } else if (n_contexts_ < max_threads_) { + // Allocate new thread context and tid. + tid = n_contexts_++; + tctx = context_factory_(tid); + threads_[tid] = tctx; + } else { +#if !SANITIZER_GO + Report("%s: Thread limit (%u threads) exceeded. Dying.\n", + SanitizerToolName, max_threads_); +#else + Printf("race: limit on %u simultaneously alive goroutines is exceeded," + " dying\n", max_threads_); +#endif + Die(); + } + CHECK_NE(tctx, 0); + CHECK_NE(tid, kUnknownTid); + CHECK_LT(tid, max_threads_); + CHECK_EQ(tctx->status, ThreadStatusInvalid); + alive_threads_++; + if (max_alive_threads_ < alive_threads_) { + max_alive_threads_++; + CHECK_EQ(alive_threads_, max_alive_threads_); + } + tctx->SetCreated(user_id, total_threads_++, detached, + parent_tid, arg); + return tid; +} + +void ThreadRegistry::RunCallbackForEachThreadLocked(ThreadCallback cb, + void *arg) { + CheckLocked(); + for (u32 tid = 0; tid < n_contexts_; tid++) { + ThreadContextBase *tctx = threads_[tid]; + if (tctx == 0) + continue; + cb(tctx, arg); + } +} + +u32 ThreadRegistry::FindThread(FindThreadCallback cb, void *arg) { + BlockingMutexLock l(&mtx_); + for (u32 tid = 0; tid < n_contexts_; tid++) { + ThreadContextBase *tctx = threads_[tid]; + if (tctx != 0 && cb(tctx, arg)) + return tctx->tid; + } + return kUnknownTid; +} + +ThreadContextBase * +ThreadRegistry::FindThreadContextLocked(FindThreadCallback cb, void *arg) { + CheckLocked(); + for (u32 tid = 0; tid < n_contexts_; tid++) { + ThreadContextBase *tctx = threads_[tid]; + if (tctx != 0 && cb(tctx, arg)) + return tctx; + } + return 0; +} + +static bool FindThreadContextByOsIdCallback(ThreadContextBase *tctx, + void *arg) { + return (tctx->os_id == (uptr)arg && tctx->status != ThreadStatusInvalid && + tctx->status != ThreadStatusDead); +} + +ThreadContextBase *ThreadRegistry::FindThreadContextByOsIDLocked(tid_t os_id) { + return FindThreadContextLocked(FindThreadContextByOsIdCallback, + (void *)os_id); +} + +void ThreadRegistry::SetThreadName(u32 tid, const char *name) { + BlockingMutexLock l(&mtx_); + CHECK_LT(tid, n_contexts_); + ThreadContextBase *tctx = threads_[tid]; + CHECK_NE(tctx, 0); + CHECK_EQ(SANITIZER_FUCHSIA ? ThreadStatusCreated : ThreadStatusRunning, + tctx->status); + tctx->SetName(name); +} + +void ThreadRegistry::SetThreadNameByUserId(uptr user_id, const char *name) { + BlockingMutexLock l(&mtx_); + for (u32 tid = 0; tid < n_contexts_; tid++) { + ThreadContextBase *tctx = threads_[tid]; + if (tctx != 0 && tctx->user_id == user_id && + tctx->status != ThreadStatusInvalid) { + tctx->SetName(name); + return; + } + } +} + +void ThreadRegistry::DetachThread(u32 tid, void *arg) { + BlockingMutexLock l(&mtx_); + CHECK_LT(tid, n_contexts_); + ThreadContextBase *tctx = threads_[tid]; + CHECK_NE(tctx, 0); + if (tctx->status == ThreadStatusInvalid) { + Report("%s: Detach of non-existent thread\n", SanitizerToolName); + return; + } + tctx->OnDetached(arg); + if (tctx->status == ThreadStatusFinished) { + tctx->SetDead(); + QuarantinePush(tctx); + } else { + tctx->detached = true; + } +} + +void ThreadRegistry::JoinThread(u32 tid, void *arg) { + bool destroyed = false; + do { + { + BlockingMutexLock l(&mtx_); + CHECK_LT(tid, n_contexts_); + ThreadContextBase *tctx = threads_[tid]; + CHECK_NE(tctx, 0); + if (tctx->status == ThreadStatusInvalid) { + Report("%s: Join of non-existent thread\n", SanitizerToolName); + return; + } + if ((destroyed = tctx->GetDestroyed())) { + tctx->SetJoined(arg); + QuarantinePush(tctx); + } + } + if (!destroyed) + internal_sched_yield(); + } while (!destroyed); +} + +// Normally this is called when the thread is about to exit. If +// called in ThreadStatusCreated state, then this thread was never +// really started. We just did CreateThread for a prospective new +// thread before trying to create it, and then failed to actually +// create it, and so never called StartThread. +void ThreadRegistry::FinishThread(u32 tid) { + BlockingMutexLock l(&mtx_); + CHECK_GT(alive_threads_, 0); + alive_threads_--; + CHECK_LT(tid, n_contexts_); + ThreadContextBase *tctx = threads_[tid]; + CHECK_NE(tctx, 0); + bool dead = tctx->detached; + if (tctx->status == ThreadStatusRunning) { + CHECK_GT(running_threads_, 0); + running_threads_--; + } else { + // The thread never really existed. + CHECK_EQ(tctx->status, ThreadStatusCreated); + dead = true; + } + tctx->SetFinished(); + if (dead) { + tctx->SetDead(); + QuarantinePush(tctx); + } + tctx->SetDestroyed(); +} + +void ThreadRegistry::StartThread(u32 tid, tid_t os_id, ThreadType thread_type, + void *arg) { + BlockingMutexLock l(&mtx_); + running_threads_++; + CHECK_LT(tid, n_contexts_); + ThreadContextBase *tctx = threads_[tid]; + CHECK_NE(tctx, 0); + CHECK_EQ(ThreadStatusCreated, tctx->status); + tctx->SetStarted(os_id, thread_type, arg); +} + +void ThreadRegistry::QuarantinePush(ThreadContextBase *tctx) { + if (tctx->tid == 0) + return; // Don't reuse the main thread. It's a special snowflake. + dead_threads_.push_back(tctx); + if (dead_threads_.size() <= thread_quarantine_size_) + return; + tctx = dead_threads_.front(); + dead_threads_.pop_front(); + CHECK_EQ(tctx->status, ThreadStatusDead); + tctx->Reset(); + tctx->reuse_count++; + if (max_reuse_ > 0 && tctx->reuse_count >= max_reuse_) + return; + invalid_threads_.push_back(tctx); +} + +ThreadContextBase *ThreadRegistry::QuarantinePop() { + if (invalid_threads_.size() == 0) + return 0; + ThreadContextBase *tctx = invalid_threads_.front(); + invalid_threads_.pop_front(); + return tctx; +} + +void ThreadRegistry::SetThreadUserId(u32 tid, uptr user_id) { + BlockingMutexLock l(&mtx_); + CHECK_LT(tid, n_contexts_); + ThreadContextBase *tctx = threads_[tid]; + CHECK_NE(tctx, 0); + CHECK_NE(tctx->status, ThreadStatusInvalid); + CHECK_NE(tctx->status, ThreadStatusDead); + CHECK_EQ(tctx->user_id, 0); + tctx->user_id = user_id; +} + +} // namespace __sanitizer |