mirror of
https://git.openldap.org/openldap/openldap.git
synced 2024-12-21 03:10:25 +08:00
563 lines
14 KiB
C
563 lines
14 KiB
C
/* $OpenLDAP$ */
|
|
/*
|
|
* Copyright 1998-2003 The OpenLDAP Foundation, Redwood City, California, USA
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms are permitted only
|
|
* as authorized by the OpenLDAP Public License. A copy of this
|
|
* license is available at http://www.OpenLDAP.org/license.html or
|
|
* in file LICENSE in the top-level directory of the distribution.
|
|
*/
|
|
|
|
#include "portable.h"
|
|
|
|
#include <stdio.h>
|
|
|
|
#include <ac/stdarg.h>
|
|
#include <ac/stdlib.h>
|
|
#include <ac/string.h>
|
|
#include <ac/time.h>
|
|
#include <ac/errno.h>
|
|
|
|
#include "ldap-int.h"
|
|
#include "ldap_pvt_thread.h"
|
|
#include "ldap_queue.h"
|
|
|
|
#ifndef LDAP_THREAD_HAVE_TPOOL
|
|
|
|
enum ldap_int_thread_pool_state {
|
|
LDAP_INT_THREAD_POOL_RUNNING,
|
|
LDAP_INT_THREAD_POOL_FINISHING,
|
|
LDAP_INT_THREAD_POOL_STOPPING
|
|
};
|
|
|
|
typedef struct ldap_int_thread_key_s {
|
|
void *ltk_key;
|
|
void *ltk_data;
|
|
ldap_pvt_thread_pool_keyfree_t *ltk_free;
|
|
} ldap_int_thread_key_t;
|
|
|
|
/* Max number of thread-specific keys we store per thread.
|
|
* We don't expect to use many...
|
|
*/
|
|
#define MAXKEYS 32
|
|
#define MAXTHREADS 1024 /* must be a power of 2 */
|
|
|
|
static ldap_pvt_thread_t tid_zero;
|
|
|
|
#ifdef HAVE_PTHREADS
|
|
#define TID_EQ(a,b) pthread_equal((a),(b))
|
|
#else
|
|
#define TID_EQ(a,b) ((a) == (b))
|
|
#endif
|
|
static struct {
|
|
ldap_pvt_thread_t id;
|
|
ldap_int_thread_key_t *ctx;
|
|
} thread_keys[MAXTHREADS];
|
|
|
|
|
|
typedef struct ldap_int_thread_ctx_s {
|
|
union {
|
|
LDAP_STAILQ_ENTRY(ldap_int_thread_ctx_s) q;
|
|
LDAP_SLIST_ENTRY(ldap_int_thread_ctx_s) l;
|
|
LDAP_SLIST_ENTRY(ldap_int_thread_ctx_s) al;
|
|
} ltc_next;
|
|
ldap_pvt_thread_start_t *ltc_start_routine;
|
|
void *ltc_arg;
|
|
} ldap_int_thread_ctx_t;
|
|
|
|
struct ldap_int_thread_pool_s {
|
|
LDAP_STAILQ_ENTRY(ldap_int_thread_pool_s) ltp_next;
|
|
ldap_pvt_thread_mutex_t ltp_mutex;
|
|
ldap_pvt_thread_cond_t ltp_cond;
|
|
LDAP_STAILQ_HEAD(tcq, ldap_int_thread_ctx_s) ltp_pending_list;
|
|
LDAP_SLIST_HEAD(tcl, ldap_int_thread_ctx_s) ltp_free_list;
|
|
LDAP_SLIST_HEAD(tclq, ldap_int_thread_ctx_s) ltp_active_list;
|
|
long ltp_state;
|
|
long ltp_max_count;
|
|
long ltp_max_pending;
|
|
long ltp_pending_count;
|
|
long ltp_active_count;
|
|
long ltp_open_count;
|
|
long ltp_starting;
|
|
};
|
|
|
|
static LDAP_STAILQ_HEAD(tpq, ldap_int_thread_pool_s)
|
|
ldap_int_thread_pool_list =
|
|
LDAP_STAILQ_HEAD_INITIALIZER(ldap_int_thread_pool_list);
|
|
|
|
static ldap_pvt_thread_mutex_t ldap_pvt_thread_pool_mutex;
|
|
|
|
static void *ldap_int_thread_pool_wrapper( void *pool );
|
|
|
|
int
|
|
ldap_int_thread_pool_startup ( void )
|
|
{
|
|
return ldap_pvt_thread_mutex_init(&ldap_pvt_thread_pool_mutex);
|
|
}
|
|
|
|
int
|
|
ldap_int_thread_pool_shutdown ( void )
|
|
{
|
|
struct ldap_int_thread_pool_s *pool;
|
|
|
|
while ((pool = LDAP_STAILQ_FIRST(&ldap_int_thread_pool_list)) != NULL) {
|
|
LDAP_STAILQ_REMOVE_HEAD(&ldap_int_thread_pool_list, ltp_next);
|
|
ldap_pvt_thread_pool_destroy( &pool, 0);
|
|
}
|
|
ldap_pvt_thread_mutex_destroy(&ldap_pvt_thread_pool_mutex);
|
|
return(0);
|
|
}
|
|
|
|
int
|
|
ldap_pvt_thread_pool_init (
|
|
ldap_pvt_thread_pool_t *tpool,
|
|
int max_threads,
|
|
int max_pending )
|
|
{
|
|
ldap_pvt_thread_pool_t pool;
|
|
int rc;
|
|
|
|
*tpool = NULL;
|
|
pool = (ldap_pvt_thread_pool_t) LDAP_CALLOC(1,
|
|
sizeof(struct ldap_int_thread_pool_s));
|
|
|
|
if (pool == NULL) return(-1);
|
|
|
|
rc = ldap_pvt_thread_mutex_init(&pool->ltp_mutex);
|
|
if (rc != 0)
|
|
return(rc);
|
|
rc = ldap_pvt_thread_cond_init(&pool->ltp_cond);
|
|
if (rc != 0)
|
|
return(rc);
|
|
pool->ltp_state = LDAP_INT_THREAD_POOL_RUNNING;
|
|
pool->ltp_max_count = max_threads;
|
|
pool->ltp_max_pending = max_pending;
|
|
LDAP_STAILQ_INIT(&pool->ltp_pending_list);
|
|
LDAP_SLIST_INIT(&pool->ltp_free_list);
|
|
LDAP_SLIST_INIT(&pool->ltp_active_list);
|
|
ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
|
|
LDAP_STAILQ_INSERT_TAIL(&ldap_int_thread_pool_list, pool, ltp_next);
|
|
ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
|
|
|
|
#if 0
|
|
/* THIS WILL NOT WORK on some systems. If the process
|
|
* forks after starting a thread, there is no guarantee
|
|
* that the thread will survive the fork. For example,
|
|
* slapd forks in order to daemonize, and does so after
|
|
* calling ldap_pvt_thread_pool_init. On some systems,
|
|
* this initial thread does not run in the child process,
|
|
* but ltp_open_count == 1, so two things happen:
|
|
* 1) the first client connection fails, and 2) when
|
|
* slapd is kill'ed, it never terminates since it waits
|
|
* for all worker threads to exit. */
|
|
|
|
/* start up one thread, just so there is one. no need to
|
|
* lock the mutex right now, since no threads are running.
|
|
*/
|
|
pool->ltp_open_count++;
|
|
|
|
ldap_pvt_thread_t thr;
|
|
rc = ldap_pvt_thread_create( &thr, 1, ldap_int_thread_pool_wrapper, pool );
|
|
|
|
if( rc != 0) {
|
|
/* couldn't start one? then don't start any */
|
|
ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
|
|
LDAP_STAILQ_REMOVE(ldap_int_thread_pool_list, pool,
|
|
ldap_int_thread_pool_s, ltp_next);
|
|
ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
|
|
ldap_pvt_thread_cond_destroy(&pool->ltp_cond);
|
|
ldap_pvt_thread_mutex_destroy(&pool->ltp_mutex);
|
|
LDAP_FREE(pool);
|
|
return(-1);
|
|
}
|
|
#endif
|
|
|
|
*tpool = pool;
|
|
return(0);
|
|
}
|
|
|
|
#define TID_HASH(tid, hash) do { int i; \
|
|
unsigned char *ptr = (unsigned char *)&(tid); \
|
|
for (i=0, hash=0; i<sizeof(tid); i++) hash += ptr[i]; } while(0)
|
|
|
|
int
|
|
ldap_pvt_thread_pool_submit (
|
|
ldap_pvt_thread_pool_t *tpool,
|
|
ldap_pvt_thread_start_t *start_routine, void *arg )
|
|
{
|
|
struct ldap_int_thread_pool_s *pool;
|
|
ldap_int_thread_ctx_t *ctx;
|
|
int need_thread = 0;
|
|
ldap_pvt_thread_t thr;
|
|
|
|
if (tpool == NULL)
|
|
return(-1);
|
|
|
|
pool = *tpool;
|
|
|
|
if (pool == NULL)
|
|
return(-1);
|
|
|
|
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
|
|
if (pool->ltp_state != LDAP_INT_THREAD_POOL_RUNNING
|
|
|| (pool->ltp_max_pending > 0
|
|
&& pool->ltp_pending_count >= pool->ltp_max_pending))
|
|
{
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
return(-1);
|
|
}
|
|
ctx = LDAP_SLIST_FIRST(&pool->ltp_free_list);
|
|
if (ctx) {
|
|
LDAP_SLIST_REMOVE_HEAD(&pool->ltp_free_list, ltc_next.l);
|
|
} else {
|
|
int i;
|
|
ctx = (ldap_int_thread_ctx_t *) LDAP_MALLOC(
|
|
sizeof(ldap_int_thread_ctx_t));
|
|
if (ctx == NULL) {
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
return(-1);
|
|
}
|
|
}
|
|
|
|
ctx->ltc_start_routine = start_routine;
|
|
ctx->ltc_arg = arg;
|
|
|
|
pool->ltp_pending_count++;
|
|
LDAP_STAILQ_INSERT_TAIL(&pool->ltp_pending_list, ctx, ltc_next.q);
|
|
ldap_pvt_thread_cond_signal(&pool->ltp_cond);
|
|
if ((pool->ltp_open_count <= 0
|
|
#if 0
|
|
|| pool->ltp_pending_count > 1
|
|
#endif
|
|
|| pool->ltp_open_count == pool->ltp_active_count)
|
|
&& (pool->ltp_max_count <= 0
|
|
|| pool->ltp_open_count < pool->ltp_max_count))
|
|
{
|
|
pool->ltp_open_count++;
|
|
pool->ltp_starting++;
|
|
need_thread = 1;
|
|
}
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
|
|
if (need_thread) {
|
|
int rc;
|
|
|
|
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
|
|
|
|
rc = ldap_pvt_thread_create( &thr, 1,
|
|
ldap_int_thread_pool_wrapper, pool );
|
|
if (rc == 0) {
|
|
int hash;
|
|
pool->ltp_starting--;
|
|
|
|
/* assign this thread ID to a key slot; start
|
|
* at the thread ID itself (mod MAXTHREADS) and
|
|
* look for an empty slot.
|
|
*/
|
|
TID_HASH(thr, hash);
|
|
for (rc = hash & (MAXTHREADS-1);
|
|
!TID_EQ(thread_keys[rc].id, tid_zero);
|
|
rc = (rc+1) & (MAXTHREADS-1));
|
|
thread_keys[rc].id = thr;
|
|
} else {
|
|
/* couldn't create thread. back out of
|
|
* ltp_open_count and check for even worse things.
|
|
*/
|
|
pool->ltp_open_count--;
|
|
pool->ltp_starting--;
|
|
if (pool->ltp_open_count == 0) {
|
|
/* no open threads at all?!?
|
|
*/
|
|
ldap_int_thread_ctx_t *ptr;
|
|
LDAP_STAILQ_FOREACH(ptr, &pool->ltp_pending_list, ltc_next.q)
|
|
if (ptr == ctx) break;
|
|
if (ptr == ctx) {
|
|
/* no open threads, context not handled, so
|
|
* back out of ltp_pending_count, free the context,
|
|
* report the error.
|
|
*/
|
|
LDAP_STAILQ_REMOVE(&pool->ltp_pending_list, ctx,
|
|
ldap_int_thread_ctx_s, ltc_next.q);
|
|
pool->ltp_pending_count++;
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
LDAP_FREE(ctx);
|
|
return(-1);
|
|
}
|
|
}
|
|
/* there is another open thread, so this
|
|
* context will be handled eventually.
|
|
* continue on and signal that the context
|
|
* is waiting.
|
|
*/
|
|
}
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
}
|
|
|
|
return(0);
|
|
}
|
|
|
|
int
|
|
ldap_pvt_thread_pool_maxthreads ( ldap_pvt_thread_pool_t *tpool, int max_threads )
|
|
{
|
|
struct ldap_int_thread_pool_s *pool;
|
|
|
|
if (tpool == NULL)
|
|
return(-1);
|
|
|
|
pool = *tpool;
|
|
|
|
if (pool == NULL)
|
|
return(-1);
|
|
|
|
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
|
|
pool->ltp_max_count = max_threads;
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
return(0);
|
|
}
|
|
|
|
int
|
|
ldap_pvt_thread_pool_backload ( ldap_pvt_thread_pool_t *tpool )
|
|
{
|
|
struct ldap_int_thread_pool_s *pool;
|
|
int count;
|
|
|
|
if (tpool == NULL)
|
|
return(-1);
|
|
|
|
pool = *tpool;
|
|
|
|
if (pool == NULL)
|
|
return(0);
|
|
|
|
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
|
|
count = pool->ltp_pending_count + pool->ltp_active_count;
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
return(count);
|
|
}
|
|
|
|
int
|
|
ldap_pvt_thread_pool_destroy ( ldap_pvt_thread_pool_t *tpool, int run_pending )
|
|
{
|
|
struct ldap_int_thread_pool_s *pool, *pptr;
|
|
long waiting;
|
|
ldap_int_thread_ctx_t *ctx;
|
|
|
|
if (tpool == NULL)
|
|
return(-1);
|
|
|
|
pool = *tpool;
|
|
|
|
if (pool == NULL) return(-1);
|
|
|
|
ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
|
|
LDAP_STAILQ_FOREACH(pptr, &ldap_int_thread_pool_list, ltp_next)
|
|
if (pptr == pool) break;
|
|
if (pptr == pool)
|
|
LDAP_STAILQ_REMOVE(&ldap_int_thread_pool_list, pool,
|
|
ldap_int_thread_pool_s, ltp_next);
|
|
ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
|
|
|
|
if (pool != pptr) return(-1);
|
|
|
|
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
|
|
pool->ltp_state = run_pending
|
|
? LDAP_INT_THREAD_POOL_FINISHING
|
|
: LDAP_INT_THREAD_POOL_STOPPING;
|
|
|
|
ldap_pvt_thread_cond_broadcast(&pool->ltp_cond);
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
|
|
do {
|
|
ldap_pvt_thread_yield();
|
|
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
|
|
waiting = pool->ltp_open_count;
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
} while (waiting > 0);
|
|
|
|
while ((ctx = LDAP_STAILQ_FIRST(&pool->ltp_pending_list)) != NULL)
|
|
{
|
|
LDAP_STAILQ_REMOVE_HEAD(&pool->ltp_pending_list, ltc_next.q);
|
|
LDAP_FREE(ctx);
|
|
}
|
|
|
|
while ((ctx = LDAP_SLIST_FIRST(&pool->ltp_free_list)) != NULL)
|
|
{
|
|
LDAP_SLIST_REMOVE_HEAD(&pool->ltp_free_list, ltc_next.l);
|
|
LDAP_FREE(ctx);
|
|
}
|
|
|
|
ldap_pvt_thread_cond_destroy(&pool->ltp_cond);
|
|
ldap_pvt_thread_mutex_destroy(&pool->ltp_mutex);
|
|
LDAP_FREE(pool);
|
|
return(0);
|
|
}
|
|
|
|
static void *
|
|
ldap_int_thread_pool_wrapper (
|
|
void *xpool )
|
|
{
|
|
struct ldap_int_thread_pool_s *pool = xpool;
|
|
ldap_int_thread_ctx_t *ctx;
|
|
ldap_int_thread_key_t ltc_key[MAXKEYS];
|
|
ldap_pvt_thread_t tid;
|
|
int i, keyslot, hash;
|
|
|
|
if (pool == NULL)
|
|
return NULL;
|
|
|
|
for ( i=0; i<MAXKEYS; i++ ) {
|
|
ltc_key[i].ltk_key = NULL;
|
|
}
|
|
|
|
tid = ldap_pvt_thread_self();
|
|
|
|
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
|
|
|
|
/* store pointer to our keys */
|
|
TID_HASH(tid, hash);
|
|
for (i = hash & (MAXTHREADS-1); !TID_EQ(thread_keys[i].id, tid);
|
|
i = (i+1) & (MAXTHREADS-1));
|
|
thread_keys[i].ctx = ltc_key;
|
|
keyslot = i;
|
|
|
|
while (pool->ltp_state != LDAP_INT_THREAD_POOL_STOPPING) {
|
|
ctx = LDAP_STAILQ_FIRST(&pool->ltp_pending_list);
|
|
if (ctx) {
|
|
LDAP_STAILQ_REMOVE_HEAD(&pool->ltp_pending_list, ltc_next.q);
|
|
} else {
|
|
if (pool->ltp_state == LDAP_INT_THREAD_POOL_FINISHING)
|
|
break;
|
|
if (pool->ltp_max_count > 0
|
|
&& pool->ltp_open_count > pool->ltp_max_count)
|
|
{
|
|
/* too many threads running (can happen if the
|
|
* maximum threads value is set during ongoing
|
|
* operation using ldap_pvt_thread_pool_maxthreads)
|
|
* so let this thread die.
|
|
*/
|
|
break;
|
|
}
|
|
|
|
/* we could check an idle timer here, and let the
|
|
* thread die if it has been inactive for a while.
|
|
* only die if there are other open threads (i.e.,
|
|
* always have at least one thread open). the check
|
|
* should be like this:
|
|
* if (pool->ltp_open_count > 1 && pool->ltp_starting == 0)
|
|
* check timer, leave thread (break;)
|
|
*/
|
|
|
|
if (pool->ltp_state == LDAP_INT_THREAD_POOL_RUNNING)
|
|
ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex);
|
|
|
|
continue;
|
|
}
|
|
|
|
pool->ltp_pending_count--;
|
|
|
|
LDAP_SLIST_INSERT_HEAD(&pool->ltp_active_list, ctx, ltc_next.al);
|
|
pool->ltp_active_count++;
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
|
|
ctx->ltc_start_routine(ltc_key, ctx->ltc_arg);
|
|
|
|
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
|
|
LDAP_SLIST_REMOVE(&pool->ltp_active_list, ctx,
|
|
ldap_int_thread_ctx_s, ltc_next.al);
|
|
LDAP_SLIST_INSERT_HEAD(&pool->ltp_free_list, ctx, ltc_next.l);
|
|
pool->ltp_active_count--;
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
|
|
ldap_pvt_thread_yield();
|
|
|
|
/* if we use an idle timer, here's
|
|
* a good place to update it
|
|
*/
|
|
|
|
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
|
|
}
|
|
|
|
for ( i=0; i<MAXKEYS && ltc_key[i].ltk_key; i++ ) {
|
|
if (ltc_key[i].ltk_free)
|
|
ltc_key[i].ltk_free(
|
|
ltc_key[i].ltk_key,
|
|
ltc_key[i].ltk_data );
|
|
}
|
|
|
|
thread_keys[keyslot].ctx = NULL;
|
|
thread_keys[keyslot].id = tid_zero;
|
|
|
|
pool->ltp_open_count--;
|
|
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
|
|
|
|
ldap_pvt_thread_exit(NULL);
|
|
return(NULL);
|
|
}
|
|
|
|
int ldap_pvt_thread_pool_getkey(
|
|
void *xctx,
|
|
void *key,
|
|
void **data,
|
|
ldap_pvt_thread_pool_keyfree_t **kfree )
|
|
{
|
|
ldap_int_thread_key_t *ctx = xctx;
|
|
int i;
|
|
|
|
if ( !ctx || !data ) return EINVAL;
|
|
|
|
for ( i=0; i<MAXKEYS && ctx[i].ltk_key; i++ ) {
|
|
if ( ctx[i].ltk_key == key ) {
|
|
*data = ctx[i].ltk_data;
|
|
if ( kfree ) *kfree = ctx[i].ltk_free;
|
|
return 0;
|
|
}
|
|
}
|
|
return ENOENT;
|
|
}
|
|
|
|
int ldap_pvt_thread_pool_setkey(
|
|
void *xctx,
|
|
void *key,
|
|
void *data,
|
|
ldap_pvt_thread_pool_keyfree_t *kfree )
|
|
{
|
|
ldap_int_thread_key_t *ctx = xctx;
|
|
int i;
|
|
|
|
if ( !ctx || !key ) return EINVAL;
|
|
|
|
for ( i=0; i<MAXKEYS; i++ ) {
|
|
if ( !ctx[i].ltk_key || ctx[i].ltk_key == key ) {
|
|
ctx[i].ltk_key = key;
|
|
ctx[i].ltk_data = data;
|
|
ctx[i].ltk_free = kfree;
|
|
return 0;
|
|
}
|
|
}
|
|
return ENOMEM;
|
|
}
|
|
|
|
/*
|
|
* This is necessary if the caller does not have access to the
|
|
* thread context handle (for example, a slapd plugin calling
|
|
* slapi_search_internal()). No doubt it is more efficient to
|
|
* for the application to keep track of the thread context
|
|
* handles itself.
|
|
*/
|
|
void *ldap_pvt_thread_pool_context( )
|
|
{
|
|
ldap_pvt_thread_t tid;
|
|
int i, hash;
|
|
|
|
tid = ldap_pvt_thread_self();
|
|
|
|
TID_HASH( tid, hash );
|
|
for (i = hash & (MAXTHREADS-1); !TID_EQ(thread_keys[i].id, tid_zero) &&
|
|
!TID_EQ(thread_keys[i].id, tid); i = (i+1) & (MAXTHREADS-1));
|
|
|
|
return thread_keys[i].ctx;
|
|
}
|
|
|
|
#endif /* LDAP_HAVE_THREAD_POOL */
|