[m-rev.] diff: fix early release of stm lock

[Peter Wang]

Julien looked at this.

Branches: main

runtime/mercury_stm.c:
        In MR_STM_block_thread, on resuming execution, don't release the STM
        lock until after removing the thread's condition variable from the
        transaction log.

diff --git a/runtime/mercury_stm.c b/runtime/mercury_stm.c
index 85634f6..73c9efa 100644
--- a/runtime/mercury_stm.c
+++ b/runtime/mercury_stm.c
@@ -370,13 +370,14 @@ MR_STM_block_thread(MR_STM_TransLog *tlog)
         fprintf(stderr, "STM BLOCKING: log <0x%.8lx>\n", (MR_Word)tlog);
 #endif
         MR_STM_condvar_wait(thread_condvar, &MR_STM_lock);
-        MR_UNLOCK(&MR_STM_lock, "MR_STM_block_thread");
 
 #if defined(MR_STM_DEBUG)
         fprintf(stderr, "STM RESCHEDULING: log <0x%.8lx>\n", (MR_Word)tlog);
 #endif
         MR_STM_unwait(tlog, thread_condvar);
 
+        MR_UNLOCK(&MR_STM_lock, "MR_STM_block_thread");
+
         MR_GC_free(thread_condvar);
 #else
     MR_fatal_error("Blocking thread in non-parallel grade");

--------------------------------------------------------------------------
mercury-reviews mailing list
Post messages to:       mercury-reviews at csse.unimelb.edu.au
Administrative Queries: owner-mercury-reviews at csse.unimelb.edu.au
Subscriptions:          mercury-reviews-request at csse.unimelb.edu.au
--------------------------------------------------------------------------