Re: [PATCH 2/7] blk-mq: abstract out blk_mq_dispatch_rq_list() helper

[Bart Van Assche]

On 12/13/2016 10:18 AM, Ritesh Harjani wrote:
On 12/9/2016 1:43 AM, Jens Axboe wrote:
+    if (!list_empty_careful(&hctx->dispatch)) {
+        spin_lock(&hctx->lock);
+        if (!list_empty(&hctx->dispatch))
list_splice_init already checks for list_empty. So this may be
redundant. Please check.

Hello Ritesh,

I think the list_empty() check is on purpose and is intended as a 
performance optimization.

Bart.