linux-kernel - [PATCH] timers: avoid an unnecessory iteration in __run

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Sun, 8 Oct 2017 20:55:59 -0700 (PDT)
From:   Zhenzhong Duan <zhenzhong.duan@...cle.com>
To:     <sboyd@...eaurora.org>, <tglx@...utronix.de>,
        <john.stultz@...aro.org>, <anna-maria@...utronix.de>
Cc:     Srinivas REDDY Eeda <srinivas.eeda@...cle.com>,
        Joe Jin <joe.jin@...cle.com>, <linux-kernel@...r.kernel.org>
Subject: [PATCH] timers: avoid an unnecessory iteration in __run_timers()

When we know next expired timer is later than current jiffies, we don't need to
call collect_expired_timers() again checking empty hlists.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@...cle.com>
---
 kernel/time/timer.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index f2674a0..02be824 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -1560,8 +1560,7 @@ static int collect_expired_timers(struct timer_base *base,
 		 * jiffies, otherwise forward to the next expiry time:
 		 */
 		if (time_after(next, jiffies)) {
-			/* The call site will increment clock! */
-			base->clk = jiffies - 1;
+			base->clk = jiffies;
 			return 0;
 		}
 		base->clk = next;
-- 
1.7.3