chromium/third_party/pthreadpool/src/src/pthreads.c

/* Standard C headers */
#include <assert.h>
#include <limits.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>

/* Configuration header */
#include "threadpool-common.h"

/* POSIX headers */
#include <pthread.h>
#include <unistd.h>

/* Futex-specific headers */
#if PTHREADPOOL_USE_FUTEX
	#if defined(__linux__)
		#include <sys/syscall.h>
		#include <linux/futex.h>

		/* Old Android NDKs do not define SYS_futex and FUTEX_PRIVATE_FLAG */
		#ifndef SYS_futex
			#define SYS_futex …
		#endif
		#ifndef FUTEX_PRIVATE_FLAG
			#define FUTEX_PRIVATE_FLAG …
		#endif
	#elif defined(__EMSCRIPTEN__)
		/* math.h for INFINITY constant */
		#include <math.h>

		#include <emscripten/threading.h>
	#else
		#error "Platform-specific implementation of futex_wait and futex_wake_all required"
	#endif
#endif

/* Windows-specific headers */
#ifdef _WIN32
	#include <sysinfoapi.h>
#endif

/* Dependencies */
#if PTHREADPOOL_USE_CPUINFO
	#include <cpuinfo.h>
#endif

/* Public library header */
#include <pthreadpool.h>

/* Internal library headers */
#include "threadpool-atomics.h"
#include "threadpool-object.h"
#include "threadpool-utils.h"


#if PTHREADPOOL_USE_FUTEX
	#if defined(__linux__)
		static int futex_wait(pthreadpool_atomic_uint32_t* address, uint32_t value) { … }

		static int futex_wake_all(pthreadpool_atomic_uint32_t* address) { … }
	#elif defined(__EMSCRIPTEN__)
		static int futex_wait(pthreadpool_atomic_uint32_t* address, uint32_t value) {
			return emscripten_futex_wait((volatile void*) address, value, INFINITY);
		}

		static int futex_wake_all(pthreadpool_atomic_uint32_t* address) {
			return emscripten_futex_wake((volatile void*) address, INT_MAX);
		}
	#else
		#error "Platform-specific implementation of futex_wait and futex_wake_all required"
	#endif
#endif

static void checkin_worker_thread(struct pthreadpool* threadpool) { … }

static void wait_worker_threads(struct pthreadpool* threadpool) { … }

static uint32_t wait_for_new_command(
	struct pthreadpool* threadpool,
	uint32_t last_command,
	uint32_t last_flags)
{ … }

static void* thread_main(void* arg) { … }

struct pthreadpool* pthreadpool_create(size_t threads_count) { … }

PTHREADPOOL_INTERNAL void pthreadpool_parallelize(
	struct pthreadpool* threadpool,
	thread_function_t thread_function,
	const void* params,
	size_t params_size,
	void* task,
	void* context,
	size_t linear_range,
	uint32_t flags)
{ … }

void pthreadpool_destroy(struct pthreadpool* threadpool) { … }