} ldap_int_thread_pool_state_t;
/* Thread-specific key with data and optional free function */
-typedef struct ldap_int_thread_key_s {
+typedef struct ldap_int_tpool_key_s {
void *ltk_key;
void *ltk_data;
ldap_pvt_thread_pool_keyfree_t *ltk_free;
-} ldap_int_thread_key_t;
+} ldap_int_tpool_key_t;
/* Max number of thread-specific keys we store per thread.
* We don't expect to use many...
*/
#define MAXKEYS 32
+
+/* Max number of threads */
#define LDAP_MAXTHR 1024 /* must be a power of 2 */
-/* User context: thread ID and thread-specific key/data pairs */
+/* Context: thread ID and thread-specific key/data pairs */
typedef struct ldap_int_thread_userctx_s {
ldap_pvt_thread_t ltu_id;
- ldap_int_thread_key_t ltu_key[MAXKEYS];
+ ldap_int_tpool_key_t ltu_key[MAXKEYS];
} ldap_int_thread_userctx_t;
-/* Simple {thread ID -> user context} hash table; key=ctx->ltu_id.
+/* Simple {thread ID -> context} hash table; key=ctx->ltu_id.
* Protected by ldap_pvt_thread_pool_mutex except during pauses,
* when it is read-only (used by pool_purgekey and pool_context).
+ * Protected by tpool->ltp_mutex during pauses.
*/
static struct {
ldap_int_thread_userctx_t *ctx;
} while(0)
-/* Thread context: operation to perform */
-typedef struct ldap_int_thread_ctx_s {
+/* Task for a thread to perform */
+typedef struct ldap_int_thread_task_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;
+ LDAP_STAILQ_ENTRY(ldap_int_thread_task_s) q;
+ LDAP_SLIST_ENTRY(ldap_int_thread_task_s) l;
+ } ltt_next;
+ ldap_pvt_thread_start_t *ltt_start_routine;
+ void *ltt_arg;
+} ldap_int_thread_task_t;
struct ldap_int_thread_pool_s {
LDAP_STAILQ_ENTRY(ldap_int_thread_pool_s) ltp_next;
- /* protect members below */
+ /* protect members below, and protect thread_keys[] during pauses */
ldap_pvt_thread_mutex_t ltp_mutex;
/* not paused and something to do for pool_<wrapper/pause/destroy>() */
/* ltp_active_count <= 1 && ltp_pause */
ldap_pvt_thread_cond_t ltp_pcond;
- LDAP_STAILQ_HEAD(tcq, ldap_int_thread_ctx_s) ltp_pending_list;
- LDAP_SLIST_HEAD(tcl, ldap_int_thread_ctx_s) ltp_free_list;
+ /* pending tasks, and unused task objects */
+ LDAP_STAILQ_HEAD(tcq, ldap_int_thread_task_s) ltp_pending_list;
+ LDAP_SLIST_HEAD(tcl, ldap_int_thread_task_s) ltp_free_list;
ldap_int_thread_pool_state_t ltp_state;
/* some active request needs to be the sole active request */
int ltp_pause;
- long ltp_max_count; /* max number of threads in pool */
- long ltp_max_pending; /* max pending or paused requests */
+ long ltp_max_count; /* max number of threads in pool, or 0 */
+ long ltp_max_pending; /* max pending or paused requests, or 0 */
long ltp_pending_count; /* pending or paused requests */
long ltp_active_count; /* active, not paused requests */
long ltp_open_count; /* number of threads */
static void *ldap_int_thread_pool_wrapper( void *pool );
-/* user context of the main thread */
+static ldap_pvt_thread_key_t ldap_tpool_key;
+
+/* Context of the main thread */
static ldap_int_thread_userctx_t ldap_int_main_thrctx;
int
ldap_int_thread_pool_startup ( void )
{
ldap_int_main_thrctx.ltu_id = ldap_pvt_thread_self();
+ ldap_pvt_thread_key_create( &ldap_tpool_key );
return ldap_pvt_thread_mutex_init(&ldap_pvt_thread_pool_mutex);
}
(ldap_pvt_thread_pool_destroy)(&pool, 0); /* ignore thr_debug macro */
}
ldap_pvt_thread_mutex_destroy(&ldap_pvt_thread_pool_mutex);
+ ldap_pvt_thread_key_destroy( ldap_tpool_key );
return(0);
}
if (! (0 <= max_threads && max_threads <= LDAP_MAXTHR))
max_threads = 0;
+ if (max_pending < 0)
+ max_pending = 0;
*tpool = NULL;
pool = (ldap_pvt_thread_pool_t) LDAP_CALLOC(1,
}
-/* Submit one operation to be performed by the thread pool */
+/* Submit a task to be performed by the thread pool */
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;
+ ldap_int_thread_task_t *task;
ldap_pvt_thread_t thr;
if (tpool == NULL)
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
if (pool->ltp_state != LDAP_INT_THREAD_POOL_RUNNING
- || (pool->ltp_max_pending > 0
+ || (pool->ltp_max_pending
&& 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);
+ task = LDAP_SLIST_FIRST(&pool->ltp_free_list);
+ if (task) {
+ LDAP_SLIST_REMOVE_HEAD(&pool->ltp_free_list, ltt_next.l);
} else {
- ctx = (ldap_int_thread_ctx_t *) LDAP_MALLOC(
- sizeof(ldap_int_thread_ctx_t));
- if (ctx == NULL) {
+ task = (ldap_int_thread_task_t *) LDAP_MALLOC(sizeof(*task));
+ if (task == NULL) {
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
return(-1);
}
}
- ctx->ltc_start_routine = start_routine;
- ctx->ltc_arg = arg;
+ task->ltt_start_routine = start_routine;
+ task->ltt_arg = arg;
pool->ltp_pending_count++;
- LDAP_STAILQ_INSERT_TAIL(&pool->ltp_pending_list, ctx, ltc_next.q);
+ LDAP_STAILQ_INSERT_TAIL(&pool->ltp_pending_list, task, ltt_next.q);
if (pool->ltp_pause) {
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
return(0);
if (pool->ltp_open_count == 0) {
/* no open threads at all?!?
*/
- ldap_int_thread_ctx_t *ptr;
+ ldap_int_thread_task_t *ptr;
/* let pool_destroy know there are no more threads */
ldap_pvt_thread_cond_signal(&pool->ltp_cond);
- 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,
+ LDAP_STAILQ_FOREACH(ptr, &pool->ltp_pending_list, ltt_next.q)
+ if (ptr == task) break;
+ if (ptr == task) {
+ /* no open threads, task not handled, so
+ * back out of ltp_pending_count, free the task,
* report the error.
*/
- LDAP_STAILQ_REMOVE(&pool->ltp_pending_list, ctx,
- ldap_int_thread_ctx_s, ltc_next.q);
+ LDAP_STAILQ_REMOVE(&pool->ltp_pending_list, task,
+ ldap_int_thread_task_s, ltt_next.q);
pool->ltp_pending_count--;
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
- LDAP_FREE(ctx);
+ LDAP_FREE(task);
return(-1);
}
}
/* there is another open thread, so this
- * context will be handled eventually.
+ * task will be handled eventually.
* continue on, we have signalled that
- * the context is waiting.
+ * the task is waiting.
*/
}
}
/* Set max #threads. value <= 0 means max supported #threads (LDAP_MAXTHR) */
int
-ldap_pvt_thread_pool_maxthreads ( ldap_pvt_thread_pool_t *tpool, int max_threads )
+ldap_pvt_thread_pool_maxthreads(
+ ldap_pvt_thread_pool_t *tpool,
+ int max_threads )
{
struct ldap_int_thread_pool_s *pool;
/* Inspect the pool */
int
-ldap_pvt_thread_pool_query ( ldap_pvt_thread_pool_t *tpool, ldap_pvt_thread_pool_param_t param, void *value )
+ldap_pvt_thread_pool_query(
+ ldap_pvt_thread_pool_t *tpool,
+ ldap_pvt_thread_pool_param_t param,
+ void *value )
{
struct ldap_int_thread_pool_s *pool;
int count = -1;
count = pool->ltp_active_count;
break;
+ case LDAP_PVT_THREAD_POOL_PARAM_PAUSING:
+ count = pool->ltp_pause;
+ break;
+
case LDAP_PVT_THREAD_POOL_PARAM_PENDING:
count = pool->ltp_pending_count;
break;
ldap_pvt_thread_pool_destroy ( ldap_pvt_thread_pool_t *tpool, int run_pending )
{
struct ldap_int_thread_pool_s *pool, *pptr;
- ldap_int_thread_ctx_t *ctx;
+ ldap_int_thread_task_t *task;
if (tpool == NULL)
return(-1);
}
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
- while ((ctx = LDAP_STAILQ_FIRST(&pool->ltp_pending_list)) != NULL)
+ while ((task = LDAP_STAILQ_FIRST(&pool->ltp_pending_list)) != NULL)
{
- LDAP_STAILQ_REMOVE_HEAD(&pool->ltp_pending_list, ltc_next.q);
- LDAP_FREE(ctx);
+ LDAP_STAILQ_REMOVE_HEAD(&pool->ltp_pending_list, ltt_next.q);
+ LDAP_FREE(task);
}
- while ((ctx = LDAP_SLIST_FIRST(&pool->ltp_free_list)) != NULL)
+ while ((task = LDAP_SLIST_FIRST(&pool->ltp_free_list)) != NULL)
{
- LDAP_SLIST_REMOVE_HEAD(&pool->ltp_free_list, ltc_next.l);
- LDAP_FREE(ctx);
+ LDAP_SLIST_REMOVE_HEAD(&pool->ltp_free_list, ltt_next.l);
+ LDAP_FREE(task);
}
ldap_pvt_thread_cond_destroy(&pool->ltp_pcond);
ldap_pvt_thread_cond_destroy(&pool->ltp_cond);
ldap_pvt_thread_mutex_destroy(&pool->ltp_mutex);
LDAP_FREE(pool);
+ *tpool = NULL;
ldap_int_has_thread_pool = 0;
return(0);
}
-/* Thread loop. Accept and handle submitted thread contexts. */
+/* Thread loop. Accept and handle submitted tasks. */
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_userctx_t uctx, *kctx;
+ ldap_int_thread_task_t *task;
+ ldap_int_thread_userctx_t ctx, *kctx;
unsigned i, keyslot, hash;
assert(pool != NULL);
for ( i=0; i<MAXKEYS; i++ ) {
- uctx.ltu_key[i].ltk_key = NULL;
+ ctx.ltu_key[i].ltk_key = NULL;
}
- uctx.ltu_id = ldap_pvt_thread_self();
- TID_HASH(uctx.ltu_id, hash);
+ ctx.ltu_id = ldap_pvt_thread_self();
+ TID_HASH(ctx.ltu_id, hash);
+
+ ldap_pvt_thread_key_setdata( ldap_tpool_key, &ctx );
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
for (keyslot = hash & (LDAP_MAXTHR-1);
(kctx = thread_keys[keyslot].ctx) && kctx != DELETED_THREAD_CTX;
keyslot = (keyslot+1) & (LDAP_MAXTHR-1));
- thread_keys[keyslot].ctx = &uctx;
+ thread_keys[keyslot].ctx = &ctx;
ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
pool->ltp_starting--;
if (pool->ltp_state == LDAP_INT_THREAD_POOL_STOPPING)
break;
- ctx = LDAP_STAILQ_FIRST(&pool->ltp_pending_list);
- if (ctx == NULL) {
+ task = LDAP_STAILQ_FIRST(&pool->ltp_pending_list);
+ if (task == NULL) {
if (pool->ltp_state == LDAP_INT_THREAD_POOL_FINISHING)
break;
continue;
}
- LDAP_STAILQ_REMOVE_HEAD(&pool->ltp_pending_list, ltc_next.q);
+ LDAP_STAILQ_REMOVE_HEAD(&pool->ltp_pending_list, ltt_next.q);
pool->ltp_pending_count--;
pool->ltp_active_count++;
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
- ctx->ltc_start_routine(&uctx, ctx->ltc_arg);
+ task->ltt_start_routine(&ctx, task->ltt_arg);
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
- LDAP_SLIST_INSERT_HEAD(&pool->ltp_free_list, ctx, ltc_next.l);
+ LDAP_SLIST_INSERT_HEAD(&pool->ltp_free_list, task, ltt_next.l);
pool->ltp_active_count--;
/* let pool_pause know when it is the sole active thread */
if (pool->ltp_active_count < 2)
ldap_pvt_thread_cond_signal(&pool->ltp_pcond);
}
- ldap_pvt_thread_pool_context_reset(&uctx);
-
- /* Needed if context_reset can let another thread request a pause */
- while (pool->ltp_pause)
- ldap_pvt_thread_cond_wait(&pool->ltp_cond, &pool->ltp_mutex);
+ /* The ltp_mutex lock protects ctx->ltu_key from pool_purgekey()
+ * during this call, since it prevents new pauses. */
+ ldap_pvt_thread_pool_context_reset(&ctx);
ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
thread_keys[keyslot].ctx = DELETED_THREAD_CTX;
ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
pool->ltp_open_count--;
-
/* let pool_destroy know we're all done */
if (pool->ltp_open_count < 1)
ldap_pvt_thread_cond_signal(&pool->ltp_cond);
ldap_pvt_thread_mutex_lock(&pool->ltp_mutex);
pool->ltp_pause = 0;
- ldap_pvt_thread_cond_broadcast(&pool->ltp_cond);
+ if (pool->ltp_state == LDAP_INT_THREAD_POOL_RUNNING)
+ ldap_pvt_thread_cond_broadcast(&pool->ltp_cond);
ldap_pvt_thread_mutex_unlock(&pool->ltp_mutex);
return(0);
}
/*
* Get the key's data and optionally free function in the given context.
- * Must not be called when the pool is paused.
*/
int ldap_pvt_thread_pool_getkey(
void *xctx,
/*
* Set or remove data for the key in the given context.
- * Must not be called when the pool is paused.
* key can be any unique pointer.
* kfree() is an optional function to free the data (but not the key):
- * pool_context_reset() and pool_purgekey() call kfree(key, data),
- * but pool_setkey() does not. For pool_setkey() it is the caller's
- * responsibility to free any existing data with the same key.
+ * pool_context_reset() and pool_purgekey() call kfree(key, data),
+ * but pool_setkey() does not. For pool_setkey() it is the caller's
+ * responsibility to free any existing data with the same key.
+ * kfree() must not call functions taking a tpool argument.
*/
int ldap_pvt_thread_pool_setkey(
void *xctx,
*/
void *ldap_pvt_thread_pool_context( )
{
- ldap_pvt_thread_t tid;
- unsigned i, hash;
- ldap_int_thread_userctx_t *ctx;
-
- tid = ldap_pvt_thread_self();
- if ( ldap_pvt_thread_equal( tid, ldap_int_main_thrctx.ltu_id ))
- return &ldap_int_main_thrctx;
-
- TID_HASH( tid, hash );
- i = hash &= (LDAP_MAXTHR-1);
- ldap_pvt_thread_mutex_lock(&ldap_pvt_thread_pool_mutex);
- do {
- ctx = thread_keys[i].ctx;
- if ( ctx == DELETED_THREAD_CTX )
- continue;
- if ( !ctx || ldap_pvt_thread_equal(thread_keys[i].ctx->ltu_id, tid) )
- goto done;
- } while ( (i = (i+1) & (LDAP_MAXTHR-1)) != hash );
- ctx = NULL;
- done:
- ldap_pvt_thread_mutex_unlock(&ldap_pvt_thread_pool_mutex);
+ void *ctx = NULL;
- return ctx;
+ ldap_pvt_thread_key_getdata( ldap_tpool_key, &ctx );
+ return ctx ? ctx : &ldap_int_main_thrctx;
}
-/* Free the context's keys. Must not be called when the pool is paused. */
+/*
+ * Free the context's keys.
+ * Must not call functions taking a tpool argument (because this
+ * thread already holds ltp_mutex when called from pool_wrapper()).
+ */
void ldap_pvt_thread_pool_context_reset( void *vctx )
{
ldap_int_thread_userctx_t *ctx = vctx;