From: Arlin Davis <arlin.r.davis@intel.com>
Date: Tue, 15 Jul 2014 20:41:10 +0000 (-0700)
Subject: common: init rbuf memory, assign hd/tl pos in range
X-Git-Url: https://openfabrics.org/gitweb/?a=commitdiff_plain;h=95935ce4a2017836fe6a29946a145929d242531c;p=~ardavis%2Fdapl.git

common: init rbuf memory, assign hd/tl pos in range

Signed-off-by: Arlin Davis <arlin.r.davis@intel.com>
---

diff --git a/dapl/common/dapl_ring_buffer_util.c b/dapl/common/dapl_ring_buffer_util.c
index 53e6426..f2fdd56 100644
--- a/dapl/common/dapl_ring_buffer_util.c
+++ b/dapl/common/dapl_ring_buffer_util.c
@@ -73,6 +73,7 @@ DAT_RETURN dapls_rbuf_alloc(INOUT DAPL_RING_BUFFER * rbuf, IN DAT_COUNT size)
 	}
 
 	rbuf->base = (void *)dapl_os_alloc(rsize * sizeof(void *));
+	dapl_os_memzero (rbuf->base, rsize * sizeof(void *));
 	if (rbuf->base != NULL) {
 		rbuf->lim = rsize - 1;
 		dapl_os_atomic_set(&rbuf->head, 0);
@@ -193,19 +194,18 @@ DAT_RETURN dapls_rbuf_add(IN DAPL_RING_BUFFER * rbuf, IN void *entry)
 	int pos;
 	int val;
 
-	while (((dapl_os_atomic_read(&rbuf->head) + 1) & rbuf->lim) !=
-	       (dapl_os_atomic_read(&rbuf->tail) & rbuf->lim)) {
+	while ((dapl_os_atomic_read(&rbuf->head) + 1) !=
+		dapl_os_atomic_read(&rbuf->tail)) {
 		pos = dapl_os_atomic_read(&rbuf->head);
-		val = dapl_os_atomic_assign(&rbuf->head, pos, pos + 1);
+		val = dapl_os_atomic_assign(&rbuf->head, pos, ((pos + 1) & rbuf->lim));
 		if (val == pos) {
 			pos = (pos + 1) & rbuf->lim;	/* verify in range */
-			rbuf->base[pos] = entry;	/* FIXME: there a race condition between this line and the line in dapls_rbuf_remove */
+			rbuf->base[pos] = entry;
 			return DAT_SUCCESS;
 		}
 	}
 
 	return DAT_ERROR(DAT_INSUFFICIENT_RESOURCES, DAT_RESOURCE_MEMORY);
-
 }
 
 /*
@@ -222,7 +222,6 @@ DAT_RETURN dapls_rbuf_add(IN DAPL_RING_BUFFER * rbuf, IN void *entry)
  * Returns:
  *	DAT_SUCCESS
  *	DAT_QUEUE_EMPTY
-   
  */
 void *dapls_rbuf_remove(IN DAPL_RING_BUFFER * rbuf)
 {
@@ -232,16 +231,14 @@ void *dapls_rbuf_remove(IN DAPL_RING_BUFFER * rbuf)
 	while (dapl_os_atomic_read(&rbuf->head) !=
 	       dapl_os_atomic_read(&rbuf->tail)) {
 		pos = dapl_os_atomic_read(&rbuf->tail);
-		val = dapl_os_atomic_assign(&rbuf->tail, pos, pos + 1);
+		val = dapl_os_atomic_assign(&rbuf->tail, pos, ((pos + 1) & rbuf->lim));
 		if (val == pos) {
 			pos = (pos + 1) & rbuf->lim;	/* verify in range */
-
-			return (rbuf->base[pos]);	/* FIXME: there a race condition between this line and the line in dapls_rbuf_add */
+			return (rbuf->base[pos]);
 		}
 	}
 
 	return NULL;
-
 }
 
 /*
diff --git a/dapl/include/dapl.h b/dapl/include/dapl.h
index 09b7a98..210f1b3 100755
--- a/dapl/include/dapl.h
+++ b/dapl/include/dapl.h
@@ -365,7 +365,6 @@ struct dapl_evd
     DAT_EVENT		*events;
     DAPL_RING_BUFFER	free_event_queue;
     DAPL_RING_BUFFER	pending_event_queue;
-    DAPL_OS_LOCK	pending_event_queue_lock; /* temporary workaround for the ring buffer race condition */
 
     /* CQ Completions are not placed into 'deferred_events'
      ** rather they are simply left on the Completion Queue