block: Make rq_affinity = 1 work as expected

Commit 5757a6d introduced a new rq_affinity = 2 so as to make the request completed in the __make_request cpu. But it makes the old rq_affinity = 1 not work any more. The root cause is that if the 'cpu' and 'req->cpu' is in the same group and cpu != req->cpu, ccpu will be the same as group_cpu, so the completion will be excuted in the 'cpu' not 'group_cpu'. This patch fix problem by simpling removing group_cpu and the codes are more explicit now. If ccpu == cpu, we complete in cpu, otherwise we raise_blk_irq to ccpu. Cc: Christoph Hellwig <[email protected]> Cc: Roland Dreier <[email protected]> Cc: Dan Williams <[email protected]> Cc: Jens Axboe <[email protected]> Signed-off-by: Tao Ma <[email protected]> Reviewed-by: Shaohua Li <[email protected]> Signed-off-by: Jens Axboe <[email protected]>
josf · Aug 5, 2011 · 35ae66e · 35ae66e
1 parent f41c53a
commit 35ae66e
Showing 1 changed file with 3 additions and 5 deletions.
diff --git a/block/blk-softirq.c b/block/blk-softirq.c
@@ -103,7 +103,7 @@ static struct notifier_block __cpuinitdata blk_cpu_notifier = {
 
 void __blk_complete_request(struct request *req)
 {
-	int ccpu, cpu, group_cpu = NR_CPUS;
+	int ccpu, cpu;
 	struct request_queue *q = req->q;
 	unsigned long flags;
 
@@ -117,14 +117,12 @@ void __blk_complete_request(struct request *req)
 	 */
 	if (test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags) && req->cpu != -1) {
 		ccpu = req->cpu;
-		if (!test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags)) {
+		if (!test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags))
 			ccpu = blk_cpu_to_group(ccpu);
-			group_cpu = blk_cpu_to_group(cpu);
-		}
 	} else
 		ccpu = cpu;
 
-	if (ccpu == cpu || ccpu == group_cpu) {
+	if (ccpu == cpu) {
 		struct list_head *list;
 do_local:
 		list = &__get_cpu_var(blk_cpu_done);