From: Sagi Grimberg <sagi@grimberg.me>
To: Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org
Cc: Christoph Hellwig <hch@lst.de>
Subject: [PATCH 2/3] irq-poll: micro optimize some branch predictions
Date: Sun, 13 Nov 2016 01:02:34 +0200 [thread overview]
Message-ID: <1478991755-28153-3-git-send-email-sagi@grimberg.me> (raw)
In-Reply-To: <1478991755-28153-1-git-send-email-sagi@grimberg.me>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
---
lib/irq_poll.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/lib/irq_poll.c b/lib/irq_poll.c
index 22d033e6ded2..44a5d1da4260 100644
--- a/lib/irq_poll.c
+++ b/lib/irq_poll.c
@@ -26,9 +26,9 @@ void irq_poll_sched(struct irq_poll *iop)
{
unsigned long flags;
- if (test_bit(IRQ_POLL_F_DISABLE, &iop->state))
+ if (unlikely(test_bit(IRQ_POLL_F_DISABLE, &iop->state)))
return;
- if (test_and_set_bit(IRQ_POLL_F_SCHED, &iop->state))
+ if (likely(test_and_set_bit(IRQ_POLL_F_SCHED, &iop->state)))
return;
local_irq_save(flags);
@@ -120,7 +120,7 @@ static void __latent_entropy irq_poll_softirq(struct softirq_action *h)
* move the instance around on the list at-will.
*/
if (work >= weight) {
- if (test_bit(IRQ_POLL_F_DISABLE, &iop->state))
+ if (unlikely(test_bit(IRQ_POLL_F_DISABLE, &iop->state)))
__irq_poll_complete(iop);
else
list_move_tail(&iop->list, list);
--
2.7.4
next prev parent reply other threads:[~2016-11-12 23:02 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-12 23:02 [PATCH 0/3] micro-optimize irq-poll Sagi Grimberg
2016-11-12 23:02 ` [PATCH 1/3] irq-poll: Remove redundant include Sagi Grimberg
2016-11-13 15:12 ` Christoph Hellwig
2016-11-12 23:02 ` Sagi Grimberg [this message]
2016-11-13 15:13 ` [PATCH 2/3] irq-poll: micro optimize some branch predictions Christoph Hellwig
2016-11-14 0:49 ` Sagi Grimberg
2016-11-12 23:02 ` [PATCH 3/3] irq-poll: Reduce local_irq_save/restore operations in irq_poll_softirq Sagi Grimberg
2016-11-13 15:18 ` Christoph Hellwig
2016-11-14 1:02 ` Sagi Grimberg
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