X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;f=libraries%2Flibldap_r%2Ftpool.c;h=e23f9ad09cf8b252c31e89308af11490431b2a41;hb=78a9d66e53923e399978e8af066e3f085ca39b53;hp=440b5a75e50084021643b9c35b76aedb7b0bfe64;hpb=f07015dad2d6ccdbe5b8360bfbc601b13baae894;p=openldap
diff --git a/libraries/libldap_r/tpool.c b/libraries/libldap_r/tpool.c
index 440b5a75e5..e23f9ad09c 100644
--- a/libraries/libldap_r/tpool.c
+++ b/libraries/libldap_r/tpool.c
@@ -1,7 +1,7 @@
/* $OpenLDAP$ */
/* This work is part of OpenLDAP Software .
*
- * Copyright 1998-2005 The OpenLDAP Foundation.
+ * Copyright 1998-2006 The OpenLDAP Foundation.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
@@ -24,17 +24,19 @@
#include
#include "ldap-int.h"
-#include "ldap_pvt_thread.h"
+#include "ldap_pvt_thread.h" /* Get the thread interface */
#include "ldap_queue.h"
+#define LDAP_THREAD_POOL_IMPLEMENTATION
+#include "ldap_thr_debug.h" /* May rename symbols defined below */
#ifndef LDAP_THREAD_HAVE_TPOOL
-enum ldap_int_thread_pool_state {
+typedef enum ldap_int_thread_pool_state_e {
LDAP_INT_THREAD_POOL_RUNNING,
LDAP_INT_THREAD_POOL_FINISHING,
LDAP_INT_THREAD_POOL_STOPPING,
LDAP_INT_THREAD_POOL_PAUSING
-};
+} ldap_int_thread_pool_state_t;
typedef struct ldap_int_thread_key_s {
void *ltk_key;
@@ -50,11 +52,6 @@ typedef struct ldap_int_thread_key_s {
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;
@@ -79,7 +76,7 @@ struct ldap_int_thread_pool_s {
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;
+ ldap_int_thread_pool_state_t ltp_state;
long ltp_max_count;
long ltp_max_pending;
long ltp_pending_count;
@@ -115,12 +112,137 @@ ldap_int_thread_pool_shutdown ( void )
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_pool_destroy)(&pool, 0); /* ignore thr_debug macro */
}
ldap_pvt_thread_mutex_destroy(&ldap_pvt_thread_pool_mutex);
return(0);
}
+typedef struct ldap_lazy_sem_t {
+ ldap_pvt_thread_mutex_t ls_mutex;
+ ldap_pvt_thread_cond_t ls_cond;
+ int ls_sem_value;
+ /*
+ * when more than ls_lazy_count number of resources
+ * becmoes available, the thread wating for the resources will
+ * be waken up in order to prevent frequent blocking/waking-up
+ */
+ unsigned int ls_lazy_count;
+ /*
+ * only one thread(listener) will wait on this semaphore
+ * using a flag instead of a list
+ */
+ int ls_wait;
+} ldap_lazy_sem_t;
+
+ldap_lazy_sem_t* thread_pool_sem = NULL;
+
+int
+ldap_lazy_sem_init( unsigned int value, unsigned int lazyness )
+{
+ thread_pool_sem = (ldap_lazy_sem_t*) LDAP_CALLOC(1,
+ sizeof( ldap_lazy_sem_t ));
+
+ if( thread_pool_sem == NULL ) return -1;
+
+ ldap_pvt_thread_mutex_init( &thread_pool_sem->ls_mutex );
+ ldap_pvt_thread_cond_init( &thread_pool_sem->ls_cond );
+ thread_pool_sem->ls_sem_value = value;
+ thread_pool_sem->ls_lazy_count = lazyness;
+ thread_pool_sem->ls_wait = 0;
+
+ return 0;
+}
+
+/* FIXME: move to some approprite header */
+int ldap_lazy_sem_dec( ldap_lazy_sem_t* ls );
+int ldap_lazy_sem_wait ( ldap_lazy_sem_t* ls );
+
+/*
+ * ldap_lazy_sem_wait is used if a caller is blockable(listener).
+ * Otherwise use ldap_lazy_sem_dec (worker)
+ */
+int
+ldap_lazy_sem_op_submit( ldap_lazy_sem_t* ls )
+{
+ if ( ls == NULL ) return -1;
+
+ /* only worker thread has its thread ctx */
+ if ( ldap_pvt_thread_pool_context() ) {
+ /* worker thread */
+ return ldap_lazy_sem_dec( ls );
+ } else {
+ /* listener */
+ return ldap_lazy_sem_wait( ls );
+ }
+}
+
+/*
+ * test if given semaphore's count is zero.
+ * If 0, the caller is blocked
+ * If not, the count is decremented.
+ */
+int
+ldap_lazy_sem_wait ( ldap_lazy_sem_t* ls )
+{
+ ldap_pvt_thread_mutex_lock( &ls->ls_mutex );
+
+lazy_sem_retry:
+ if ( ls->ls_sem_value <= 0 ) {
+ /* no more avaliable resources */
+ ls->ls_wait = 1;
+ ldap_pvt_thread_cond_wait( &ls->ls_cond, &ls->ls_mutex );
+ goto lazy_sem_retry;
+ } else {
+ /* avaliable resources */
+ ls->ls_sem_value--;
+ }
+
+ ldap_pvt_thread_mutex_unlock( &ls->ls_mutex );
+
+ return 0;
+}
+
+/*
+ * decrement the count without blocking
+ * even when the count becomes less than or equal to 0
+ */
+int
+ldap_lazy_sem_dec( ldap_lazy_sem_t* ls )
+{
+ ldap_pvt_thread_mutex_lock( &ls->ls_mutex );
+
+ ls->ls_sem_value--;
+
+ ldap_pvt_thread_mutex_unlock( &ls->ls_mutex );
+
+ return 0;
+}
+
+/*
+ * Increment the count by one and test if it is greater or
+ * equal to lazyness. If it is, wake up a blocked thread.
+ */
+int
+ldap_lazy_sem_post( ldap_lazy_sem_t* ls )
+{
+ if( ls == NULL ) return (-1);
+
+ ldap_pvt_thread_mutex_lock( &ls->ls_mutex );
+
+ ls->ls_sem_value++;
+ if ( ls->ls_wait ) {
+ if ( ls->ls_sem_value >= ls->ls_lazy_count ) {
+ ls->ls_wait = 0;
+ ldap_pvt_thread_cond_signal( &ls->ls_cond );
+ }
+ }
+
+ ldap_pvt_thread_mutex_unlock( &ls->ls_mutex );
+
+ return 0;
+}
+
int
ldap_pvt_thread_pool_init (
ldap_pvt_thread_pool_t *tpool,
@@ -193,7 +315,7 @@ ldap_pvt_thread_pool_init (
return(0);
}
-#define TID_HASH(tid, hash) do { int i; \
+#define TID_HASH(tid, hash) do { unsigned i; \
unsigned char *ptr = (unsigned char *)&(tid); \
for (i=0, hash=0; iltp_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))
+ if (pool->ltp_open_count < pool->ltp_active_count + pool->ltp_pending_count
+ && (pool->ltp_open_count < pool->ltp_max_count ||
+ pool->ltp_max_count <= 0 ))
{
pool->ltp_open_count++;
pool->ltp_starting++;
@@ -260,6 +378,10 @@ ldap_pvt_thread_pool_submit (
}
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
+#ifdef LDAP_PVT_THREAD_POOL_SEM_LOAD_CONTROL
+ ldap_lazy_sem_op_submit( thread_pool_sem );
+#endif
+
if (need_thread) {
int rc;
@@ -277,7 +399,7 @@ ldap_pvt_thread_pool_submit (
*/
TID_HASH(thr, hash);
for (rc = hash & (LDAP_MAXTHR-1);
- !TID_EQ(thread_keys[rc].id, tid_zero);
+ !ldap_pvt_thread_equal(thread_keys[rc].id, tid_zero);
rc = (rc+1) & (LDAP_MAXTHR-1));
thread_keys[rc].id = thr;
} else {
@@ -411,6 +533,11 @@ ldap_pvt_thread_pool_destroy ( ldap_pvt_thread_pool_t *tpool, int run_pending )
ldap_pvt_thread_cond_destroy(&pool->ltp_cond);
ldap_pvt_thread_mutex_destroy(&pool->ltp_mutex);
LDAP_FREE(pool);
+#ifdef LDAP_PVT_THREAD_POOL_SEM_LOAD_CONTROL
+ if ( thread_pool_sem ) {
+ LDAP_FREE( thread_pool_sem );
+ }
+#endif
return(0);
}
@@ -437,7 +564,8 @@ ldap_int_thread_pool_wrapper (
/* store pointer to our keys */
TID_HASH(tid, hash);
- for (i = hash & (LDAP_MAXTHR-1); !TID_EQ(thread_keys[i].id, tid);
+ for (i = hash & (LDAP_MAXTHR-1);
+ !ldap_pvt_thread_equal(thread_keys[i].id, tid);
i = (i+1) & (LDAP_MAXTHR-1));
thread_keys[i].ctx = ltc_key;
keyslot = i;
@@ -467,10 +595,16 @@ ldap_int_thread_pool_wrapper (
* should be like this:
* if (pool->ltp_open_count > 1 && pool->ltp_starting == 0)
* check timer, leave thread (break;)
+ *
+ * Just use pthread_cond_timedwait if we want to
+ * check idle time.
*/
- if (pool->ltp_state == LDAP_INT_THREAD_POOL_RUNNING)
+ if (pool->ltp_state == LDAP_INT_THREAD_POOL_RUNNING
+ || pool->ltp_state == LDAP_INT_THREAD_POOL_PAUSING)
+ {
ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex);
+ }
continue;
}
@@ -483,6 +617,9 @@ ldap_int_thread_pool_wrapper (
ctx->ltc_start_routine(ltc_key, ctx->ltc_arg);
+#ifdef LDAP_PVT_THREAD_POOL_SEM_LOAD_CONTROL
+ ldap_lazy_sem_post( thread_pool_sem );
+#endif
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
LDAP_SLIST_REMOVE(&pool->ltp_active_list, ctx,
ldap_int_thread_ctx_s, ltc_next.al);
@@ -495,15 +632,6 @@ ldap_int_thread_pool_wrapper (
}
ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex);
}
- 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; iltp_mutex);
/* If someone else has already requested a pause, we have to wait */
- if (pool->ltp_state == LDAP_INT_THREAD_POOL_PAUSING) {
+ while (pool->ltp_state == LDAP_INT_THREAD_POOL_PAUSING) {
pool->ltp_pending_count++;
pool->ltp_active_count--;
ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex);
@@ -658,12 +786,14 @@ void *ldap_pvt_thread_pool_context( )
int i, hash;
tid = ldap_pvt_thread_self();
- if ( TID_EQ( tid, ldap_int_main_tid ))
+ if ( ldap_pvt_thread_equal( tid, ldap_int_main_tid ))
return ldap_int_main_thrctx;
TID_HASH( tid, hash );
- for (i = hash & (LDAP_MAXTHR-1); !TID_EQ(thread_keys[i].id, tid_zero) &&
- !TID_EQ(thread_keys[i].id, tid); i = (i+1) & (LDAP_MAXTHR-1));
+ for (i = hash & (LDAP_MAXTHR-1);
+ !ldap_pvt_thread_equal(thread_keys[i].id, tid_zero) &&
+ !ldap_pvt_thread_equal(thread_keys[i].id, tid);
+ i = (i+1) & (LDAP_MAXTHR-1));
return thread_keys[i].ctx;
}