Speedup for pthread implementation. We make use of thread local storage

to allow access to the current thread's resources without having to
obtain the memory mutex and traverse our hash table. This is a big
performance win!

diff --git a/TSRM/TSRM.c b/TSRM/TSRM.c
index d92d1e7f074ef64682375836a657afea4c26fcba..24d8ea969e6c3fbceb731057271037b431908fa9 100644 (file)
--- a/TSRM/TSRM.c
+++ b/TSRM/TSRM.c
@@ -59,6 +59,9 @@ static void (*tsrm_new_thread_end_handler)();
 
 /* Debug support */
 int tsrm_error(int level, const char *format, ...);
+
+/* Read a resource from a thread's resource storage */
+void *ts_resource_read( tsrm_tls_entry *thread_resources, ts_rsrc_id id );
 static int tsrm_error_level;
 static FILE *tsrm_error_file;
 #if TSRM_DEBUG
@@ -69,11 +72,19 @@ static FILE *tsrm_error_file;
 #define TSRM_SAFE_ARRAY_OFFSET(array, offset, range)   array[offset]
 #endif
 
+#if defined(PTHREADS)
+/* Thread local storage */
+static pthread_key_t tls_key;
+#endif
+
+
 /* Startup TSRM (call once for the entire process) */
 TSRM_API int tsrm_startup(int expected_threads, int expected_resources, int debug_level, char *debug_filename)
 {
 #if defined(GNUPTH)
        pth_init();
+#elif defined(PTHREADS)
+       pthread_key_create( &tls_key, 0 );
 #endif
 
        tsrm_error_file = stderr;
@@ -141,6 +152,8 @@ TSRM_API void tsrm_shutdown(void)
        }
 #if defined(GNUPTH)
        pth_kill();
+#elif defined(PTHREADS)
+        pthread_key_delete( tls_key );
 #endif
 }
 
@@ -211,7 +224,10 @@ static void allocate_new_resource(tsrm_tls_entry **thread_resources_ptr, THREAD_
        (*thread_resources_ptr)->thread_id = thread_id;
        (*thread_resources_ptr)->next = NULL;
 
-       tsrm_mutex_unlock(tsmm_mutex);
+#if defined(PTHREADS)
+        /* Set thread local storage to this new thread resources structure */
+        pthread_setspecific( tls_key, (void *)*thread_resources_ptr );
+#endif
 
        if (tsrm_new_thread_begin_handler) {
                tsrm_new_thread_begin_handler(thread_id);
@@ -222,6 +238,9 @@ static void allocate_new_resource(tsrm_tls_entry **thread_resources_ptr, THREAD_
                        resource_types_table[i].ctor((*thread_resources_ptr)->storage[i]);
                }
        }
+
+       tsrm_mutex_unlock(tsmm_mutex);
+
        if (tsrm_new_thread_end_handler) {
                tsrm_new_thread_end_handler(thread_id);
        }
@@ -234,13 +253,25 @@ TSRM_API void *ts_resource_ex(ts_rsrc_id id, THREAD_T *th_id)
        THREAD_T thread_id;
        int hash_value;
        tsrm_tls_entry *thread_resources;
-       void *resource;
 
-       if (th_id) {
-               thread_id = *th_id;
-       } else {
+        if( !th_id ) {
+#if defined(PTHREADS)
+                /* Fast path for looking up the resources for the current
+                 * thread. Its used by just about every call to
+                 * ts_resource_ex(). This avoids the need for a mutex lock
+                 * and our hashtable lookup.
+                 */
+                thread_resources = pthread_getspecific( tls_key );
+                if( thread_resources ) {
+                        TSRM_ERROR(TSRM_ERROR_LEVEL_INFO, "Fetching resource id %d for current thread %d", id, (long) thread_resources->thread_id );
+                        return ts_resource_read( thread_resources, id );
+                }
+#endif
                thread_id = tsrm_thread_id();
-       }
+       } else {
+               thread_id = *th_id;
+        }
+
        TSRM_ERROR(TSRM_ERROR_LEVEL_INFO, "Fetching resource id %d for thread %ld", id, (long) thread_id);
        tsrm_mutex_lock(tsmm_mutex);
 
@@ -250,7 +281,6 @@ TSRM_API void *ts_resource_ex(ts_rsrc_id id, THREAD_T *th_id)
        if (!thread_resources) {
                allocate_new_resource(&tsrm_tls_table[hash_value], thread_id);
                return ts_resource_ex(id, &thread_id);
-               /* thread_resources = tsrm_tls_table[hash_value]; */
        } else {
                 do {
                        if (thread_resources->thread_id == thread_id) {
@@ -268,15 +298,25 @@ TSRM_API void *ts_resource_ex(ts_rsrc_id id, THREAD_T *th_id)
                        }
                 } while (thread_resources);
        }
+       tsrm_mutex_unlock(tsmm_mutex);
+        return ts_resource_read( thread_resources, id );
+}
 
-       resource = TSRM_SAFE_ARRAY_OFFSET(thread_resources->storage, TSRM_UNSHUFFLE_RSRC_ID(id), thread_resources->count);
 
-       tsrm_mutex_unlock(tsmm_mutex);
+/* Read a specific resource from the thread's resources.
+ * This is called outside of a mutex, so have to be aware about external
+ * changes to the structure as we read it.
+ */
+void *ts_resource_read( tsrm_tls_entry *thread_resources, ts_rsrc_id id )
+{
+       void *resource;
 
+       resource = TSRM_SAFE_ARRAY_OFFSET(thread_resources->storage, TSRM_UNSHUFFLE_RSRC_ID(id), thread_resources->count);
        if (resource) {
-               TSRM_ERROR(TSRM_ERROR_LEVEL_INFO, "Successfully fetched resource id %d for thread id %ld - %x", id, (long) thread_id, (long) resource);
+               TSRM_ERROR(TSRM_ERROR_LEVEL_INFO, "Successfully fetched resource id %d for thread id %ld - %x", id, (long) thread_resources->thread_id, (long) resource);
        } else {
                TSRM_ERROR(TSRM_ERROR_LEVEL_ERROR, "Resource id %d is out of range (%d..%d)", id, TSRM_SHUFFLE_RSRC_ID(0), TSRM_SHUFFLE_RSRC_ID(thread_resources->count-1));
+                abort();
        }
        return resource;
 }
@@ -285,9 +325,10 @@ TSRM_API void *ts_resource_ex(ts_rsrc_id id, THREAD_T *th_id)
 /* frees all resources allocated for the current thread */
 void ts_free_thread(void)
 {
+       tsrm_tls_entry *thread_resources;
+        int i;
        THREAD_T thread_id = tsrm_thread_id();
        int hash_value;
-       tsrm_tls_entry *thread_resources;
        tsrm_tls_entry *last=NULL;
 
        tsrm_mutex_lock(tsmm_mutex);
@@ -296,20 +337,26 @@ void ts_free_thread(void)
 
        while (thread_resources) {
                if (thread_resources->thread_id == thread_id) {
-                       int i;
+                        tsrm_mutex_unlock(tsmm_mutex);
 
                        for (i=0; i<thread_resources->count; i++) {
                                if (resource_types_table[i].dtor) {
                                        resource_types_table[i].dtor(thread_resources->storage[i]);
-                               }
+                                }
+                        }
+                       for (i=0; i<thread_resources->count; i++) {
                                free(thread_resources->storage[i]);
                        }
+                        tsrm_mutex_lock(tsmm_mutex);
                        free(thread_resources->storage);
                        if (last) {
                                last->next = thread_resources->next;
                        } else {
                                tsrm_tls_table[hash_value]=NULL;
                        }
+#if defined(PTHREADS)
+                        pthread_setspecific( tls_key, 0 );
+#endif                        
                        free(thread_resources);
                        break;
                }