[ofa-general] [PATCH] opensm/osm_state_mgr.c: bug fix in unicast cache

[Yevgeny Kliteynik]

Hi Sasha,

When there are errors during initialization and new
heavy sweep is forced, unicast cache might hold a
snapshot of the previous routing, and since there
might be no *topology* changes, ucast cache will
apply that cached routing, which might be wrong.

This patch invalidates cache explicitly if there
were initialization errors in addition to few other
cases.

This fix addresses bug #1398.

Signed-off-by: Yevgeny Kliteynik <kliteyn at dev.mellanox.co.il>
---
 opensm/opensm/osm_state_mgr.c |   16 ++++++++++++----
 1 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/opensm/opensm/osm_state_mgr.c b/opensm/opensm/osm_state_mgr.c
index 841438c..d00e8ff 100644
--- a/opensm/opensm/osm_state_mgr.c
+++ b/opensm/opensm/osm_state_mgr.c
@@ -1064,6 +1064,18 @@ static void do_sweep(osm_sm_t * sm)
 	}

 	/*
+	 * Unicast cache should be invalidated if:
+	 *  - every sweep is a heavy sweep
+	 *  - there were errors during initialization
+	 *  - subnet re-route is requested
+	 */
+	if (sm->p_subn->opt.use_ucast_cache &&
+	    (sm->p_subn->opt.force_heavy_sweep ||
+	     sm->p_subn->subnet_initialization_error ||
+	     sm->p_subn->force_reroute))
+		osm_ucast_cache_invalidate(&sm->ucast_mgr);
+
+	/*
 	 * If we don't need to do a heavy sweep and we want to do a reroute,
 	 * just reroute only.
 	 */
@@ -1079,10 +1091,6 @@ static void do_sweep(osm_sm_t * sm)
 		/* Re-program the switches fully */
 		sm->p_subn->ignore_existing_lfts = TRUE;

-		/* we want to re-route, so cache should be invalidated */
-		if (sm->p_subn->opt.use_ucast_cache)
-			osm_ucast_cache_invalidate(&sm->ucast_mgr);
-
 		osm_ucast_mgr_process(&sm->ucast_mgr);

 		/* Reset flag */
-- 
1.5.1.4