Changeset 19449

Timestamp:

Sep 9, 2008, 4:48:32 PM (18 years ago)

Author:

Paul Price

Message:

I think the memory corruption in subMask when running threaded is due
to using psThreadPoolWait to harvest the jobs. I don't think we can
rely on psThreadPoolWait to harvest the jobs because the job contains
a reference to the subMask, which is being changed on a thread, and
psThreadPoolWait doesn't know that it needs to be locked before
freeing. After psThreadPoolWait, however, the jobs are completed, the
threads are idle, and so there's no need to lock the subMask when
we're blowing away the jobs.

File:

• branches/pap_branch_080908/psModules/src/imcombine/pmSubtraction.c (modified) (2 diffs)

branches/pap_branch_080908/psModules/src/imcombine/pmSubtraction.c

@@ -1141 +1141 @@
                     psMutexLock(subMask);
                 }
-                psArrayAdd(args, 1, (psImage*)subMask); // Casting away const
+                psArrayAdd(args, 1, subMask);
                 if (subMask) {
                     psMutexUnlock(subMask);
@@ -1166 +1166 @@
     }
 
-    if (!psThreadPoolWait(true)) {
+    if (!psThreadPoolWait(false)) {
         psError(PS_ERR_UNKNOWN, false, "Error waiting for threads.");
         return false;
     }
 
-    if (subMask && threaded) {
-        psMutexDestroy(subMask);
+    // We don't rely on psThreadPoolWait to harvest the jobs because the job contains a reference to the
+    // subMask, which is being changed on a thread, and psThreadPoolWait doesn't know that it needs to be
+    // locked before freeing.  After psThreadPoolWait, however, the jobs are completed, the threads are idle,
+    // and so there's no need to lock the subMask when we're blowing away the jobs.
+    if (threaded) {
+        psThreadJob *job;               // Completed job
+        while ((job = psThreadJobGetDone())) {
+            psFree(job);
+        }
+
+        if (subMask) {
+            psMutexDestroy(subMask);
+        }
     }