summaryrefslogtreecommitdiff
path: root/vendor/github.com/DataDog/zstd/pool.c
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/github.com/DataDog/zstd/pool.c')
-rw-r--r--vendor/github.com/DataDog/zstd/pool.c340
1 files changed, 0 insertions, 340 deletions
diff --git a/vendor/github.com/DataDog/zstd/pool.c b/vendor/github.com/DataDog/zstd/pool.c
deleted file mode 100644
index 7a8294543..000000000
--- a/vendor/github.com/DataDog/zstd/pool.c
+++ /dev/null
@@ -1,340 +0,0 @@
-/*
- * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
- * All rights reserved.
- *
- * This source code is licensed under both the BSD-style license (found in the
- * LICENSE file in the root directory of this source tree) and the GPLv2 (found
- * in the COPYING file in the root directory of this source tree).
- * You may select, at your option, one of the above-listed licenses.
- */
-
-
-/* ====== Dependencies ======= */
-#include <stddef.h> /* size_t */
-#include "debug.h" /* assert */
-#include "zstd_internal.h" /* ZSTD_malloc, ZSTD_free */
-#include "pool.h"
-
-/* ====== Compiler specifics ====== */
-#if defined(_MSC_VER)
-# pragma warning(disable : 4204) /* disable: C4204: non-constant aggregate initializer */
-#endif
-
-
-#ifdef ZSTD_MULTITHREAD
-
-#include "threading.h" /* pthread adaptation */
-
-/* A job is a function and an opaque argument */
-typedef struct POOL_job_s {
- POOL_function function;
- void *opaque;
-} POOL_job;
-
-struct POOL_ctx_s {
- ZSTD_customMem customMem;
- /* Keep track of the threads */
- ZSTD_pthread_t* threads;
- size_t threadCapacity;
- size_t threadLimit;
-
- /* The queue is a circular buffer */
- POOL_job *queue;
- size_t queueHead;
- size_t queueTail;
- size_t queueSize;
-
- /* The number of threads working on jobs */
- size_t numThreadsBusy;
- /* Indicates if the queue is empty */
- int queueEmpty;
-
- /* The mutex protects the queue */
- ZSTD_pthread_mutex_t queueMutex;
- /* Condition variable for pushers to wait on when the queue is full */
- ZSTD_pthread_cond_t queuePushCond;
- /* Condition variables for poppers to wait on when the queue is empty */
- ZSTD_pthread_cond_t queuePopCond;
- /* Indicates if the queue is shutting down */
- int shutdown;
-};
-
-/* POOL_thread() :
- * Work thread for the thread pool.
- * Waits for jobs and executes them.
- * @returns : NULL on failure else non-null.
- */
-static void* POOL_thread(void* opaque) {
- POOL_ctx* const ctx = (POOL_ctx*)opaque;
- if (!ctx) { return NULL; }
- for (;;) {
- /* Lock the mutex and wait for a non-empty queue or until shutdown */
- ZSTD_pthread_mutex_lock(&ctx->queueMutex);
-
- while ( ctx->queueEmpty
- || (ctx->numThreadsBusy >= ctx->threadLimit) ) {
- if (ctx->shutdown) {
- /* even if !queueEmpty, (possible if numThreadsBusy >= threadLimit),
- * a few threads will be shutdown while !queueEmpty,
- * but enough threads will remain active to finish the queue */
- ZSTD_pthread_mutex_unlock(&ctx->queueMutex);
- return opaque;
- }
- ZSTD_pthread_cond_wait(&ctx->queuePopCond, &ctx->queueMutex);
- }
- /* Pop a job off the queue */
- { POOL_job const job = ctx->queue[ctx->queueHead];
- ctx->queueHead = (ctx->queueHead + 1) % ctx->queueSize;
- ctx->numThreadsBusy++;
- ctx->queueEmpty = ctx->queueHead == ctx->queueTail;
- /* Unlock the mutex, signal a pusher, and run the job */
- ZSTD_pthread_cond_signal(&ctx->queuePushCond);
- ZSTD_pthread_mutex_unlock(&ctx->queueMutex);
-
- job.function(job.opaque);
-
- /* If the intended queue size was 0, signal after finishing job */
- ZSTD_pthread_mutex_lock(&ctx->queueMutex);
- ctx->numThreadsBusy--;
- if (ctx->queueSize == 1) {
- ZSTD_pthread_cond_signal(&ctx->queuePushCond);
- }
- ZSTD_pthread_mutex_unlock(&ctx->queueMutex);
- }
- } /* for (;;) */
- assert(0); /* Unreachable */
-}
-
-POOL_ctx* POOL_create(size_t numThreads, size_t queueSize) {
- return POOL_create_advanced(numThreads, queueSize, ZSTD_defaultCMem);
-}
-
-POOL_ctx* POOL_create_advanced(size_t numThreads, size_t queueSize,
- ZSTD_customMem customMem) {
- POOL_ctx* ctx;
- /* Check parameters */
- if (!numThreads) { return NULL; }
- /* Allocate the context and zero initialize */
- ctx = (POOL_ctx*)ZSTD_calloc(sizeof(POOL_ctx), customMem);
- if (!ctx) { return NULL; }
- /* Initialize the job queue.
- * It needs one extra space since one space is wasted to differentiate
- * empty and full queues.
- */
- ctx->queueSize = queueSize + 1;
- ctx->queue = (POOL_job*)ZSTD_malloc(ctx->queueSize * sizeof(POOL_job), customMem);
- ctx->queueHead = 0;
- ctx->queueTail = 0;
- ctx->numThreadsBusy = 0;
- ctx->queueEmpty = 1;
- (void)ZSTD_pthread_mutex_init(&ctx->queueMutex, NULL);
- (void)ZSTD_pthread_cond_init(&ctx->queuePushCond, NULL);
- (void)ZSTD_pthread_cond_init(&ctx->queuePopCond, NULL);
- ctx->shutdown = 0;
- /* Allocate space for the thread handles */
- ctx->threads = (ZSTD_pthread_t*)ZSTD_malloc(numThreads * sizeof(ZSTD_pthread_t), customMem);
- ctx->threadCapacity = 0;
- ctx->customMem = customMem;
- /* Check for errors */
- if (!ctx->threads || !ctx->queue) { POOL_free(ctx); return NULL; }
- /* Initialize the threads */
- { size_t i;
- for (i = 0; i < numThreads; ++i) {
- if (ZSTD_pthread_create(&ctx->threads[i], NULL, &POOL_thread, ctx)) {
- ctx->threadCapacity = i;
- POOL_free(ctx);
- return NULL;
- } }
- ctx->threadCapacity = numThreads;
- ctx->threadLimit = numThreads;
- }
- return ctx;
-}
-
-/*! POOL_join() :
- Shutdown the queue, wake any sleeping threads, and join all of the threads.
-*/
-static void POOL_join(POOL_ctx* ctx) {
- /* Shut down the queue */
- ZSTD_pthread_mutex_lock(&ctx->queueMutex);
- ctx->shutdown = 1;
- ZSTD_pthread_mutex_unlock(&ctx->queueMutex);
- /* Wake up sleeping threads */
- ZSTD_pthread_cond_broadcast(&ctx->queuePushCond);
- ZSTD_pthread_cond_broadcast(&ctx->queuePopCond);
- /* Join all of the threads */
- { size_t i;
- for (i = 0; i < ctx->threadCapacity; ++i) {
- ZSTD_pthread_join(ctx->threads[i], NULL); /* note : could fail */
- } }
-}
-
-void POOL_free(POOL_ctx *ctx) {
- if (!ctx) { return; }
- POOL_join(ctx);
- ZSTD_pthread_mutex_destroy(&ctx->queueMutex);
- ZSTD_pthread_cond_destroy(&ctx->queuePushCond);
- ZSTD_pthread_cond_destroy(&ctx->queuePopCond);
- ZSTD_free(ctx->queue, ctx->customMem);
- ZSTD_free(ctx->threads, ctx->customMem);
- ZSTD_free(ctx, ctx->customMem);
-}
-
-
-
-size_t POOL_sizeof(POOL_ctx *ctx) {
- if (ctx==NULL) return 0; /* supports sizeof NULL */
- return sizeof(*ctx)
- + ctx->queueSize * sizeof(POOL_job)
- + ctx->threadCapacity * sizeof(ZSTD_pthread_t);
-}
-
-
-/* @return : 0 on success, 1 on error */
-static int POOL_resize_internal(POOL_ctx* ctx, size_t numThreads)
-{
- if (numThreads <= ctx->threadCapacity) {
- if (!numThreads) return 1;
- ctx->threadLimit = numThreads;
- return 0;
- }
- /* numThreads > threadCapacity */
- { ZSTD_pthread_t* const threadPool = (ZSTD_pthread_t*)ZSTD_malloc(numThreads * sizeof(ZSTD_pthread_t), ctx->customMem);
- if (!threadPool) return 1;
- /* replace existing thread pool */
- memcpy(threadPool, ctx->threads, ctx->threadCapacity * sizeof(*threadPool));
- ZSTD_free(ctx->threads, ctx->customMem);
- ctx->threads = threadPool;
- /* Initialize additional threads */
- { size_t threadId;
- for (threadId = ctx->threadCapacity; threadId < numThreads; ++threadId) {
- if (ZSTD_pthread_create(&threadPool[threadId], NULL, &POOL_thread, ctx)) {
- ctx->threadCapacity = threadId;
- return 1;
- } }
- } }
- /* successfully expanded */
- ctx->threadCapacity = numThreads;
- ctx->threadLimit = numThreads;
- return 0;
-}
-
-/* @return : 0 on success, 1 on error */
-int POOL_resize(POOL_ctx* ctx, size_t numThreads)
-{
- int result;
- if (ctx==NULL) return 1;
- ZSTD_pthread_mutex_lock(&ctx->queueMutex);
- result = POOL_resize_internal(ctx, numThreads);
- ZSTD_pthread_cond_broadcast(&ctx->queuePopCond);
- ZSTD_pthread_mutex_unlock(&ctx->queueMutex);
- return result;
-}
-
-/**
- * Returns 1 if the queue is full and 0 otherwise.
- *
- * When queueSize is 1 (pool was created with an intended queueSize of 0),
- * then a queue is empty if there is a thread free _and_ no job is waiting.
- */
-static int isQueueFull(POOL_ctx const* ctx) {
- if (ctx->queueSize > 1) {
- return ctx->queueHead == ((ctx->queueTail + 1) % ctx->queueSize);
- } else {
- return (ctx->numThreadsBusy == ctx->threadLimit) ||
- !ctx->queueEmpty;
- }
-}
-
-
-static void POOL_add_internal(POOL_ctx* ctx, POOL_function function, void *opaque)
-{
- POOL_job const job = {function, opaque};
- assert(ctx != NULL);
- if (ctx->shutdown) return;
-
- ctx->queueEmpty = 0;
- ctx->queue[ctx->queueTail] = job;
- ctx->queueTail = (ctx->queueTail + 1) % ctx->queueSize;
- ZSTD_pthread_cond_signal(&ctx->queuePopCond);
-}
-
-void POOL_add(POOL_ctx* ctx, POOL_function function, void* opaque)
-{
- assert(ctx != NULL);
- ZSTD_pthread_mutex_lock(&ctx->queueMutex);
- /* Wait until there is space in the queue for the new job */
- while (isQueueFull(ctx) && (!ctx->shutdown)) {
- ZSTD_pthread_cond_wait(&ctx->queuePushCond, &ctx->queueMutex);
- }
- POOL_add_internal(ctx, function, opaque);
- ZSTD_pthread_mutex_unlock(&ctx->queueMutex);
-}
-
-
-int POOL_tryAdd(POOL_ctx* ctx, POOL_function function, void* opaque)
-{
- assert(ctx != NULL);
- ZSTD_pthread_mutex_lock(&ctx->queueMutex);
- if (isQueueFull(ctx)) {
- ZSTD_pthread_mutex_unlock(&ctx->queueMutex);
- return 0;
- }
- POOL_add_internal(ctx, function, opaque);
- ZSTD_pthread_mutex_unlock(&ctx->queueMutex);
- return 1;
-}
-
-
-#else /* ZSTD_MULTITHREAD not defined */
-
-/* ========================== */
-/* No multi-threading support */
-/* ========================== */
-
-
-/* We don't need any data, but if it is empty, malloc() might return NULL. */
-struct POOL_ctx_s {
- int dummy;
-};
-static POOL_ctx g_ctx;
-
-POOL_ctx* POOL_create(size_t numThreads, size_t queueSize) {
- return POOL_create_advanced(numThreads, queueSize, ZSTD_defaultCMem);
-}
-
-POOL_ctx* POOL_create_advanced(size_t numThreads, size_t queueSize, ZSTD_customMem customMem) {
- (void)numThreads;
- (void)queueSize;
- (void)customMem;
- return &g_ctx;
-}
-
-void POOL_free(POOL_ctx* ctx) {
- assert(!ctx || ctx == &g_ctx);
- (void)ctx;
-}
-
-int POOL_resize(POOL_ctx* ctx, size_t numThreads) {
- (void)ctx; (void)numThreads;
- return 0;
-}
-
-void POOL_add(POOL_ctx* ctx, POOL_function function, void* opaque) {
- (void)ctx;
- function(opaque);
-}
-
-int POOL_tryAdd(POOL_ctx* ctx, POOL_function function, void* opaque) {
- (void)ctx;
- function(opaque);
- return 1;
-}
-
-size_t POOL_sizeof(POOL_ctx* ctx) {
- if (ctx==NULL) return 0; /* supports sizeof NULL */
- assert(ctx == &g_ctx);
- return sizeof(*ctx);
-}
-
-#endif /* ZSTD_MULTITHREAD */