From d4d03e36e5990c8cb51eb759821c3f447af79c9f Mon Sep 17 00:00:00 2001
From: Mark Valence <mrv@openldap.org>
Date: Tue, 4 Jul 2000 19:24:13 +0000
Subject: [PATCH] Added "threads" config to slapd.conf.

---
 include/ldap_pvt_thread.h   |  7 ++++++-
 libraries/libldap_r/tpool.c | 34 ++++++++++++++++++++++++++++++++--
 servers/slapd/config.c      | 21 +++++++++++++++++++++
 servers/slapd/init.c        |  2 +-
 servers/slapd/slap.h        |  2 ++
 5 files changed, 62 insertions(+), 4 deletions(-)

diff --git a/include/ldap_pvt_thread.h b/include/ldap_pvt_thread.h
index 5b65406731..da0a3fcdf0 100644
--- a/include/ldap_pvt_thread.h
+++ b/include/ldap_pvt_thread.h
@@ -138,7 +138,7 @@ typedef ldap_int_thread_pool_t ldap_pvt_thread_pool_t;
 LDAP_F( int )
 ldap_pvt_thread_pool_init LDAP_P((
 	ldap_pvt_thread_pool_t *pool_out,
-	int max_concurrency,
+	int max_threads,
 	int max_pending ));
 
 LDAP_F( int )
@@ -147,6 +147,11 @@ ldap_pvt_thread_pool_submit LDAP_P((
 	void *(*start_routine)( void * ),
 	void *arg ));
 
+LDAP_F( int )
+ldap_pvt_thread_pool_maxthreads LDAP_P((
+	ldap_pvt_thread_pool_t *pool,
+	int max_threads ));
+
 LDAP_F( int )
 ldap_pvt_thread_pool_backload LDAP_P((
 	ldap_pvt_thread_pool_t *pool ));
diff --git a/libraries/libldap_r/tpool.c b/libraries/libldap_r/tpool.c
index ba44fb22cc..c99450c320 100644
--- a/libraries/libldap_r/tpool.c
+++ b/libraries/libldap_r/tpool.c
@@ -85,7 +85,7 @@ ldap_int_thread_pool_shutdown ( void )
 int
 ldap_pvt_thread_pool_init (
 	ldap_pvt_thread_pool_t *tpool,
-	int max_concurrency,
+	int max_threads,
 	int max_pending )
 {
 	ldap_pvt_thread_pool_t pool;
@@ -104,7 +104,7 @@ ldap_pvt_thread_pool_init (
 	if (rc != 0)
 		return(rc);
 	pool->ltp_state = LDAP_INT_THREAD_POOL_RUNNING;
-	pool->ltp_max_count = max_concurrency;
+	pool->ltp_max_count = max_threads;
 	pool->ltp_max_pending = max_pending;
 	ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
 	ldap_int_thread_enlist(&ldap_int_thread_pool_list, pool);
@@ -235,6 +235,25 @@ ldap_pvt_thread_pool_submit (
 	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 )
 {
@@ -325,6 +344,17 @@ ldap_int_thread_pool_wrapper (
 		if (ctx == NULL) {
 			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.,
diff --git a/servers/slapd/config.c b/servers/slapd/config.c
index f5041fe007..e031402ec8 100644
--- a/servers/slapd/config.c
+++ b/servers/slapd/config.c
@@ -161,6 +161,27 @@ read_config( const char *fname )
 
 			ldap_pvt_thread_set_concurrency( c );
 
+		/* set maximum threads in thread pool */
+		} else if ( strcasecmp( cargv[0], "threads" ) == 0 ) {
+			int c;
+			if ( cargc < 2 ) {
+				Debug( LDAP_DEBUG_ANY,
+	    "%s: line %d: missing count in \"threads <count>\" line\n",
+				    fname, lineno, 0 );
+				return( 1 );
+			}
+
+			c = atoi( cargv[1] );
+
+			if( c < 0 ) {
+				Debug( LDAP_DEBUG_ANY,
+	    "%s: line %d: invalid level (%d) in \"threads <count>\" line\n",
+				    fname, lineno, c );
+				return( 1 );
+			}
+
+			ldap_pvt_thread_pool_maxthreads( &connection_pool, c );
+
 		/* get pid file name */
 		} else if ( strcasecmp( cargv[0], "pidfile" ) == 0 ) {
 			if ( cargc < 2 ) {
diff --git a/servers/slapd/init.c b/servers/slapd/init.c
index cda4397d1a..2e25add973 100644
--- a/servers/slapd/init.c
+++ b/servers/slapd/init.c
@@ -94,7 +94,7 @@ slap_init( int mode, const char *name )
 	
 			(void) ldap_pvt_thread_initialize();
 
-			ldap_pvt_thread_pool_init(&connection_pool, 0, 0);
+			ldap_pvt_thread_pool_init(&connection_pool, SLAP_MAX_WORKER_THREADS, 0);
 
 			ldap_pvt_thread_mutex_init( &currenttime_mutex );
 			ldap_pvt_thread_mutex_init( &entry2str_mutex );
diff --git a/servers/slapd/slap.h b/servers/slapd/slap.h
index e2ddbacca3..c55f231966 100644
--- a/servers/slapd/slap.h
+++ b/servers/slapd/slap.h
@@ -62,6 +62,8 @@ LDAP_BEGIN_DECL
 
 #define MAXREMATCHES 10
 
+#define SLAP_MAX_WORKER_THREADS		32
+
 
 /* psuedo error code indicating abandoned operation */
 #define SLAPD_ABANDON (-1)
-- 
2.39.5