[pypy-commit] stmgc c7: reducing number of aborts by sleeping

[Raemi]

Author: Remi Meier <remi.meier at gmail.com>
Branch: c7
Changeset: r636:94b61d8b586a
Date: 2014-01-17 23:25 +0100
http://bitbucket.org/pypy/stmgc/changeset/94b61d8b586a/

Log:	reducing number of aborts by sleeping

diff --git a/c7/core.c b/c7/core.c
--- a/c7/core.c
+++ b/c7/core.c
@@ -376,6 +376,9 @@
     uintptr_t lock_idx = (((uintptr_t)obj) >> 4) - READMARKER_START;
     uint8_t previous;
     while ((previous = __sync_lock_test_and_set(&write_locks[lock_idx], 1))) {
+        usleep(1);              /* XXXXXX */
+        if (!(previous = __sync_lock_test_and_set(&write_locks[lock_idx], 1))) 
+            break;
         stm_abort_transaction();
         /* XXX: only abort if we are younger */
         spin_loop();
@@ -897,6 +900,7 @@
 
     _STM_TL2->running_transaction = 0;
     stm_stop_lock();
+    fprintf(stderr, "%c", 'C'+_STM_TL2->thread_num*32);
 }
 
 
@@ -975,7 +979,7 @@
     assert(_STM_TL1->jmpbufptr != (jmpbufptr_t *)-1);   /* for tests only */
     _STM_TL2->running_transaction = 0;
     stm_stop_lock();
-    fprintf(stderr, "a");
+    fprintf(stderr, "%c", 'A'+_STM_TL2->thread_num*32);
 
     /* reset all the modified objects (incl. re-adding GCFLAG_WRITE_BARRIER) */
     reset_modified_from_other_threads();