added exact timing semantics on blocking locks

(This used to be commit aed32eb412cab7f6d0959f9faaaebdb320b2b6a8)

2 files changed, 27 insertions, 12 deletions

diff --git a/source3/smbd/blocking.c b/source3/smbd/blocking.c
index 72cf3e59b6..9d411711cb 100644
--- a/source3/smbd/blocking.c
+++ b/source3/smbd/blocking.c
@@ -531,13 +531,33 @@ file %s fnum = %d\n", blr->com_type, fsp->fsp_name, fsp->fnum ));
 }
 
 /****************************************************************************
- Return True if the blocking lock queue has entries.
+ Return the number of seconds to the next blocking locks timeout, or default_timeout
 *****************************************************************************/
-
-BOOL blocking_locks_pending(void)
+unsigned blocking_locks_timeout(unsigned default_timeout)
 {
-  blocking_lock_record *blr = (blocking_lock_record *)ubi_slFirst( &blocking_lock_queue );
-  return (blr == NULL ? False : True);
+	unsigned timeout = default_timeout;
+	time_t t;
+	blocking_lock_record *blr = (blocking_lock_record *)ubi_slFirst(&blocking_lock_queue);
+
+	/* note that we avoid the time() syscall if there are no blocking locks */
+	if (!blr) {
+		return timeout;
+	}
+
+	t = time(NULL);
+
+	while (blr) {
+		if (timeout > (blr->expire_time - t)) {
+			timeout = blr->expire_time - t;
+		}
+		blr = (blocking_lock_record *)ubi_slNext(blr);
+	}
+
+	if (timeout < 1) {
+		timeout = 1;
+	}
+
+	return timeout;
 }
 
 /****************************************************************************
diff --git a/source3/smbd/process.c b/source3/smbd/process.c
index 55234ec896..13fd4998fe 100644
--- a/source3/smbd/process.c
+++ b/source3/smbd/process.c
@@ -1032,13 +1032,8 @@ static int setup_select_timeout(void)
 	int select_timeout;
 	int t;
 
-	/*
-	 * Increase the select timeout back to SMBD_SELECT_TIMEOUT if we
-	 * have removed any blocking locks. JRA.
-	 */
-
-	select_timeout = blocking_locks_pending() ? SMBD_SELECT_TIMEOUT_WITH_PENDING_LOCKS*1000 :
-		SMBD_SELECT_TIMEOUT*1000;
+	select_timeout = blocking_locks_timeout(SMBD_SELECT_TIMEOUT);
+	select_timeout *= 1000;
 
 	t = change_notify_timeout();
 	if (t != -1) select_timeout = MIN(select_timeout, t*1000);