[PATCH] block: remove WQ_POWER_EFFICIENT from kblockd
From: Matias BjÃrling
Date: Wed Jun 11 2014 - 17:44:22 EST
blk-mq issues async requests through kblockd. To issue a work request on a
specific CPU, kblockd_schedule_delayed_work_on is used. However, the CPU can
change if the machine is a laptop or similar. In that case its
workqueue.power_efficient parameter is set to true. That enables kblockd to be
WQ_UNBOUND by default. Leaving blk-mq to bounce its hw ctx queues between CPUs.
Remove the kblockd WQ_POWER_EFFICIENT flag to prevent this behavior.
Signed-off-by: Matias BjÃrling <m@xxxxxxxxxxx>
---
block/blk-core.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/block/blk-core.c b/block/blk-core.c
index f6f6b9a..6f8dba1 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -3312,8 +3312,7 @@ int __init blk_dev_init(void)
/* used for unplugging and affects IO latency/throughput - HIGHPRI */
kblockd_workqueue = alloc_workqueue("kblockd",
- WQ_MEM_RECLAIM | WQ_HIGHPRI |
- WQ_POWER_EFFICIENT, 0);
+ WQ_MEM_RECLAIM | WQ_HIGHPRI, 0);
if (!kblockd_workqueue)
panic("Failed to create kblockd\n");
--
1.9.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/