protect buffer pool with a mutex

This commit is contained in:
Yann Collet 2016-12-28 15:31:19 +01:00
parent 3d93f2fce7
commit ce9e1452fd

View File

@ -1,5 +1,5 @@
#include <stdlib.h> /* malloc */
#include <pthread.h>
#include <pthread.h> /* posix only, to be replaced by a more portable version */
#include "zstd_internal.h" /* MIN, ERROR */
#include "zstdmt_compress.h"
@ -39,7 +39,7 @@ static ZSTDMT_dstBufferManager ZSTDMT_createDstBufferManager(void* dst, size_t d
dbm.frameIDToWrite = 0;
pthread_mutex_init(&dbm.frameTable_mutex, NULL);
pthread_mutex_init(&dbm.allFramesWritten_mutex, NULL);
pthread_mutex_lock(&dbm.allFramesWritten_mutex);
pthread_mutex_lock(&dbm.allFramesWritten_mutex); /* maybe could be merged into init ? */
dbm.nbStackedFrames = 0;
return dbm;
}
@ -92,7 +92,7 @@ static size_t ZSTDMT_tryWriteFrame(ZSTDMT_dstBufferManager* dstBufferManager,
pthread_mutex_lock(&dstBufferManager->frameTable_mutex);
if (frameID != dstBufferManager->frameIDToWrite) {
DEBUGLOG(4, "writing frameID %u : not possible, waiting for %u ", frameID, dstBufferManager->frameIDToWrite);
frameToWrite_t frame = { src, srcSize, frameID, isLastFrame };
frameToWrite_t const frame = { src, srcSize, frameID, isLastFrame };
ZSTDMT_stackFrameToWrite(dstBufferManager, frame);
pthread_mutex_unlock(&dstBufferManager->frameTable_mutex);
return 0;
@ -121,9 +121,11 @@ static size_t ZSTDMT_tryWriteFrame(ZSTDMT_dstBufferManager* dstBufferManager,
for (u=0; u<dstBufferManager->nbStackedFrames; u++) {
if (dstBufferManager->stackedFrame[u].frameID == frameID) {
pthread_mutex_unlock(&dstBufferManager->frameTable_mutex);
DEBUGLOG(4, "catch up frame %u ", frameID);
{ size_t const writeError = ZSTDMT_writeFrame(dstBufferManager, u);
if (ZSTD_isError(writeError)) return writeError; }
lastFrameWritten = dstBufferManager->stackedFrame[u].isLastFrame;
dstBufferManager->frameIDToWrite = frameID+1;
/* remove frame from stack */
pthread_mutex_lock(&dstBufferManager->frameTable_mutex);
dstBufferManager->stackedFrame[u] = dstBufferManager->stackedFrame[dstBufferManager->nbStackedFrames-1];
@ -183,20 +185,24 @@ static ZSTDMT_jobDescription ZSTDMT_getjob(ZSTDMT_jobAgency* jobAgency)
#define ZSTDMT_NBBUFFERSPOOLED_MAX ZSTDMT_NBTHREADS_MAX
typedef struct ZSTDMT_bufferPool_s {
pthread_mutex_t bufferPool_mutex;
buffer_t bTable[ZSTDMT_NBBUFFERSPOOLED_MAX];
unsigned nbBuffers;
} ZSTDMT_bufferPool;
static buffer_t ZSTDMT_getBuffer(ZSTDMT_bufferPool* pool, size_t bSize)
{
pthread_mutex_lock(&pool->bufferPool_mutex);
if (pool->nbBuffers) { /* try to use an existing buffer */
pool->nbBuffers--;
buffer_t const buf = pool->bTable[pool->nbBuffers];
pthread_mutex_unlock(&pool->bufferPool_mutex);
size_t const availBufferSize = buf.bufferSize;
if ((availBufferSize >= bSize) & (availBufferSize <= 10*bSize)) /* large enough, but not too much */
return buf;
free(buf.start); /* size conditions not respected : create a new buffer */
}
pthread_mutex_unlock(&pool->bufferPool_mutex);
/* create new buffer */
buffer_t buf;
buf.bufferSize = bSize;
@ -207,11 +213,14 @@ static buffer_t ZSTDMT_getBuffer(ZSTDMT_bufferPool* pool, size_t bSize)
/* effectively store buffer for later re-use, up to pool capacity */
static void ZSTDMT_releaseBuffer(ZSTDMT_bufferPool* pool, buffer_t buf)
{
pthread_mutex_lock(&pool->bufferPool_mutex);
if (pool->nbBuffers >= ZSTDMT_NBBUFFERSPOOLED_MAX) {
pthread_mutex_unlock(&pool->bufferPool_mutex);
free(buf.start);
return;
}
pool->bTable[pool->nbBuffers++] = buf; /* store for later re-use */
pthread_mutex_unlock(&pool->bufferPool_mutex);
}
@ -253,9 +262,12 @@ ZSTDMT_CCtx *ZSTDMT_createCCtx(unsigned nbThreads)
if ((nbThreads < 1) | (nbThreads > ZSTDMT_NBTHREADS_MAX)) return NULL;
ZSTDMT_CCtx* const cctx = (ZSTDMT_CCtx*) calloc(1, sizeof(ZSTDMT_CCtx));
if (!cctx) return NULL;
/* init jobAgency */
pthread_mutex_init(&cctx->jobAgency.jobAnnounce_mutex, NULL); /* check return value ? */
pthread_mutex_init(&cctx->jobAgency.jobApply_mutex, NULL);
pthread_mutex_lock(&cctx->jobAgency.jobAnnounce_mutex); /* no job at beginning */
/* init bufferPool */
pthread_mutex_init(&cctx->bufferPool.bufferPool_mutex, NULL);
/* start all workers */
cctx->nbThreads = nbThreads;
DEBUGLOG(2, "nbThreads : %u \n", nbThreads);