Import my recent 1:1 threading working. some features improved includes:

 1. fast simple type mutex.
 2. __thread tls works.
 3. asynchronous cancellation works ( using signal ).
 4. thread synchronization is fully based on umtx, mainly, condition
    variable and other synchronization objects were rewritten by using
    umtx directly. those objects can be shared between processes via
    shared memory, it has to change ABI which does not happen yet.
 5. default stack size is increased to 1M on 32 bits platform, 2M for
    64 bits platform.
As the result, some mysql super-smack benchmarks show performance is
improved massivly.

Okayed by: jeff, mtm, rwatson, scottl

1 files changed, 7 insertions, 10 deletions

diff --git a/lib/libthr/thread/thr_atfork.c b/lib/libthr/thread/thr_atfork.c
index 214424a..370623a 100644
--- a/lib/libthr/thread/thr_atfork.c
+++ b/lib/libthr/thread/thr_atfork.c
@@ -23,16 +23,13 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
+ * $FreeBSD$
  */
 
-#include <sys/cdefs.h>
-__FBSDID("$FreeBSD$");
-
 #include <errno.h>
 #include <stdlib.h>
 #include <pthread.h>
 #include <sys/queue.h>
-
 #include "thr_private.h"
 
 __weak_reference(_pthread_atfork, pthread_atfork);
@@ -41,20 +38,20 @@ int
 _pthread_atfork(void (*prepare)(void), void (*parent)(void),
     void (*child)(void))
 {
+	struct pthread *curthread;
 	struct pthread_atfork *af;
 
-	if (_thread_initial == NULL)
-		_thread_init();
+	_thr_check_init();
 
 	if ((af = malloc(sizeof(struct pthread_atfork))) == NULL)
 		return (ENOMEM);
 
+	curthread = _get_curthread();
 	af->prepare = prepare;
 	af->parent = parent;
 	af->child = child;
-	_pthread_mutex_lock(&_atfork_mutex);
-	TAILQ_INSERT_TAIL(&_atfork_list, af, qe);
-	_pthread_mutex_unlock(&_atfork_mutex);
+	THR_UMTX_LOCK(curthread, &_thr_atfork_lock);
+	TAILQ_INSERT_TAIL(&_thr_atfork_list, af, qe);
+	THR_UMTX_UNLOCK(curthread, &_thr_atfork_lock);
 	return (0);
 }
-