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Diffstat (limited to '')
| -rw-r--r-- | third_party/aom/aom_util/aom_thread.c | 240 |
1 files changed, 240 insertions, 0 deletions
diff --git a/third_party/aom/aom_util/aom_thread.c b/third_party/aom/aom_util/aom_thread.c new file mode 100644 index 0000000000..fa3b0a25e4 --- /dev/null +++ b/third_party/aom/aom_util/aom_thread.c @@ -0,0 +1,240 @@ +/* + * Copyright (c) 2016, Alliance for Open Media. All rights reserved + * + * This source code is subject to the terms of the BSD 2 Clause License and + * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License + * was not distributed with this source code in the LICENSE file, you can + * obtain it at www.aomedia.org/license/software. If the Alliance for Open + * Media Patent License 1.0 was not distributed with this source code in the + * PATENTS file, you can obtain it at www.aomedia.org/license/patent. + */ +// +// Multi-threaded worker +// +// Original source: +// https://chromium.googlesource.com/webm/libwebp + +// Enable GNU extensions in glibc so that we can call pthread_setname_np(). +// This must be before any #include statements. +#ifndef _GNU_SOURCE +#define _GNU_SOURCE +#endif + +#include <assert.h> +#include <string.h> // for memset() + +#include "aom_mem/aom_mem.h" +#include "aom_ports/sanitizer.h" +#include "aom_util/aom_thread.h" + +#if CONFIG_MULTITHREAD + +struct AVxWorkerImpl { + pthread_mutex_t mutex_; + pthread_cond_t condition_; + pthread_t thread_; +}; + +//------------------------------------------------------------------------------ + +static void execute(AVxWorker *const worker); // Forward declaration. + +static THREADFN thread_loop(void *ptr) { + AVxWorker *const worker = (AVxWorker *)ptr; +#ifdef __APPLE__ + if (worker->thread_name != NULL) { + // Apple's version of pthread_setname_np takes one argument and operates on + // the current thread only. The maximum size of the thread_name buffer was + // noted in the Chromium source code and was confirmed by experiments. If + // thread_name is too long, pthread_setname_np returns -1 with errno + // ENAMETOOLONG (63). + char thread_name[64]; + strncpy(thread_name, worker->thread_name, sizeof(thread_name) - 1); + thread_name[sizeof(thread_name) - 1] = '\0'; + pthread_setname_np(thread_name); + } +#elif (defined(__GLIBC__) && !defined(__GNU__)) || defined(__BIONIC__) + if (worker->thread_name != NULL) { + // Linux and Android require names (with nul) fit in 16 chars, otherwise + // pthread_setname_np() returns ERANGE (34). + char thread_name[16]; + strncpy(thread_name, worker->thread_name, sizeof(thread_name) - 1); + thread_name[sizeof(thread_name) - 1] = '\0'; + pthread_setname_np(pthread_self(), thread_name); + } +#endif + pthread_mutex_lock(&worker->impl_->mutex_); + for (;;) { + while (worker->status_ == OK) { // wait in idling mode + pthread_cond_wait(&worker->impl_->condition_, &worker->impl_->mutex_); + } + if (worker->status_ == WORK) { + // When worker->status_ is WORK, the main thread doesn't change + // worker->status_ and will wait until the worker changes worker->status_ + // to OK. See change_state(). So the worker can safely call execute() + // without holding worker->impl_->mutex_. When the worker reacquires + // worker->impl_->mutex_, worker->status_ must still be WORK. + pthread_mutex_unlock(&worker->impl_->mutex_); + execute(worker); + pthread_mutex_lock(&worker->impl_->mutex_); + assert(worker->status_ == WORK); + worker->status_ = OK; + // signal to the main thread that we're done (for sync()) + pthread_cond_signal(&worker->impl_->condition_); + } else { + assert(worker->status_ == NOT_OK); // finish the worker + break; + } + } + pthread_mutex_unlock(&worker->impl_->mutex_); + return THREAD_RETURN(NULL); // Thread is finished +} + +// main thread state control +static void change_state(AVxWorker *const worker, AVxWorkerStatus new_status) { + // No-op when attempting to change state on a thread that didn't come up. + // Checking status_ without acquiring the lock first would result in a data + // race. + if (worker->impl_ == NULL) return; + + pthread_mutex_lock(&worker->impl_->mutex_); + if (worker->status_ >= OK) { + // wait for the worker to finish + while (worker->status_ != OK) { + pthread_cond_wait(&worker->impl_->condition_, &worker->impl_->mutex_); + } + // assign new status and release the working thread if needed + if (new_status != OK) { + worker->status_ = new_status; + pthread_cond_signal(&worker->impl_->condition_); + } + } + pthread_mutex_unlock(&worker->impl_->mutex_); +} + +#endif // CONFIG_MULTITHREAD + +//------------------------------------------------------------------------------ + +static void init(AVxWorker *const worker) { + memset(worker, 0, sizeof(*worker)); + worker->status_ = NOT_OK; +} + +static int sync(AVxWorker *const worker) { +#if CONFIG_MULTITHREAD + change_state(worker, OK); +#endif + assert(worker->status_ <= OK); + return !worker->had_error; +} + +static int reset(AVxWorker *const worker) { + int ok = 1; + worker->had_error = 0; + if (worker->status_ < OK) { +#if CONFIG_MULTITHREAD + worker->impl_ = (AVxWorkerImpl *)aom_calloc(1, sizeof(*worker->impl_)); + if (worker->impl_ == NULL) { + return 0; + } + if (pthread_mutex_init(&worker->impl_->mutex_, NULL)) { + goto Error; + } + if (pthread_cond_init(&worker->impl_->condition_, NULL)) { + pthread_mutex_destroy(&worker->impl_->mutex_); + goto Error; + } + pthread_attr_t attr; + if (pthread_attr_init(&attr)) goto Error2; + // Debug ASan builds require at least ~1MiB of stack; prevents + // failures on macOS arm64 where the default is 512KiB. + // See: https://crbug.com/aomedia/3379 +#if defined(AOM_ADDRESS_SANITIZER) && defined(__APPLE__) && AOM_ARCH_ARM && \ + !defined(NDEBUG) + size_t stacksize; + if (!pthread_attr_getstacksize(&attr, &stacksize)) { + const size_t kMinStackSize = 1 << 20; // 1 MiB + if (stacksize < kMinStackSize && + pthread_attr_setstacksize(&attr, kMinStackSize)) { + pthread_attr_destroy(&attr); + goto Error2; + } + } +#endif + pthread_mutex_lock(&worker->impl_->mutex_); + ok = !pthread_create(&worker->impl_->thread_, &attr, thread_loop, worker); + if (ok) worker->status_ = OK; + pthread_mutex_unlock(&worker->impl_->mutex_); + pthread_attr_destroy(&attr); + if (!ok) { + Error2: + pthread_mutex_destroy(&worker->impl_->mutex_); + pthread_cond_destroy(&worker->impl_->condition_); + Error: + aom_free(worker->impl_); + worker->impl_ = NULL; + return 0; + } +#else + worker->status_ = OK; +#endif + } else if (worker->status_ > OK) { + ok = sync(worker); + } + assert(!ok || (worker->status_ == OK)); + return ok; +} + +static void execute(AVxWorker *const worker) { + if (worker->hook != NULL) { + worker->had_error |= !worker->hook(worker->data1, worker->data2); + } +} + +static void launch(AVxWorker *const worker) { +#if CONFIG_MULTITHREAD + change_state(worker, WORK); +#else + execute(worker); +#endif +} + +static void end(AVxWorker *const worker) { +#if CONFIG_MULTITHREAD + if (worker->impl_ != NULL) { + change_state(worker, NOT_OK); + pthread_join(worker->impl_->thread_, NULL); + pthread_mutex_destroy(&worker->impl_->mutex_); + pthread_cond_destroy(&worker->impl_->condition_); + aom_free(worker->impl_); + worker->impl_ = NULL; + } +#else + worker->status_ = NOT_OK; + assert(worker->impl_ == NULL); +#endif + assert(worker->status_ == NOT_OK); +} + +//------------------------------------------------------------------------------ + +static AVxWorkerInterface g_worker_interface = { init, reset, sync, + launch, execute, end }; + +int aom_set_worker_interface(const AVxWorkerInterface *const winterface) { + if (winterface == NULL || winterface->init == NULL || + winterface->reset == NULL || winterface->sync == NULL || + winterface->launch == NULL || winterface->execute == NULL || + winterface->end == NULL) { + return 0; + } + g_worker_interface = *winterface; + return 1; +} + +const AVxWorkerInterface *aom_get_worker_interface(void) { + return &g_worker_interface; +} + +//------------------------------------------------------------------------------ |