From: Luke Browning <lukebr@linux.vnet.ibm.com>
Date: Thu, 20 Dec 2007 07:39:59 +0000 (+0900)
Subject: [POWERPC] spufs: spu_find_victim may choose wrong victim
X-Git-Tag: v3.12-rc1~24022^2~213
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=b192541b39ed29ff82f9f2d5427f451e89617f1c;p=kernel%2Fkernel-generic.git

[POWERPC] spufs: spu_find_victim may choose wrong victim

Need to re-check priority after dropping lock.  Otherwise, a
more favored context may be preempted.

Signed-off-by: Luke Browning <lukebr@linux.vnet.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
---

diff --git a/arch/powerpc/platforms/cell/spufs/sched.c b/arch/powerpc/platforms/cell/spufs/sched.c
index ef0e5e2..54b338f 100644
--- a/arch/powerpc/platforms/cell/spufs/sched.c
+++ b/arch/powerpc/platforms/cell/spufs/sched.c
@@ -626,10 +626,10 @@ static struct spu *find_victim(struct spu_context *ctx)
 			}
 
 			spu = victim->spu;
-			if (!spu) {
+			if (!spu || victim->prio <= ctx->prio) {
 				/*
 				 * This race can happen because we've dropped
-				 * the active list mutex.  No a problem, just
+				 * the active list mutex.  Not a problem, just
 				 * restart the search.
 				 */
 				mutex_unlock(&victim->state_mutex);