2015-12-02 11:22:20

by Raghavendra K T

Subject: [PATCH] blk-mq: Reuse hardware context cpumask for tags

hctx->cpumask is already populated and let the tag cpumask follow that
instead of going through a new for loop.

Signed-off-by: Raghavendra K T <[email protected]>
---
block/blk-mq.c | 9 +--------
1 file changed, 1 insertion(+), 8 deletions(-)

Nish had suggested to put cpumask_copy after WARN_ON (instead of before).

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 6d6f8fe..6ada3b4 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1854,6 +1854,7 @@ static void blk_mq_map_swqueue(struct request_queue *q,
hctx->tags = set->tags[i];
WARN_ON(!hctx->tags);

+ cpumask_copy(hctx->tags->cpumask, hctx->cpumask);
/*
* Set the map size to the number of mapped software queues.
* This is more accurate and more efficient than looping
@@ -1867,14 +1868,6 @@ static void blk_mq_map_swqueue(struct request_queue *q,
hctx->next_cpu = cpumask_first(hctx->cpumask);
hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH;
}
-
- queue_for_each_ctx(q, ctx, i) {
- if (!cpumask_test_cpu(i, online_mask))
- continue;
-
- hctx = q->mq_ops->map_queue(q, i);
- cpumask_set_cpu(i, hctx->tags->cpumask);
- }
}

static void queue_set_hctx_shared(struct request_queue *q, bool shared)
--
1.7.11.7

2015-12-03 10:04:08

by Sagi Grimberg

Subject: Re: [PATCH] blk-mq: Reuse hardware context cpumask for tags

Looks good,

Reviewed-by: Sagi Grimberg <[email protected]>

2015-12-03 16:56:44

by Jens Axboe

Subject: Re: [PATCH] blk-mq: Reuse hardware context cpumask for tags

On 12/02/2015 04:27 AM, Raghavendra K T wrote:
> hctx->cpumask is already populated and let the tag cpumask follow that
> instead of going through a new for loop.

Applied for 4.5, thanks.

--
Jens Axboe