linux-kernel - [tip:timers/core] tick: sched: Remove hrtimer

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

Date:	Wed, 22 Apr 2015 12:09:21 -0700
From:	tip-bot for Thomas Gleixner <tipbot@...or.com>
To:	linux-tip-commits@...r.kernel.org
Cc:	tglx@...utronix.de, preeti@...ux.vnet.ibm.com,
	peterz@...radead.org, hpa@...or.com, mtosatti@...hat.com,
	fweisbec@...il.com, mingo@...nel.org, john.stultz@...aro.org,
	linux-kernel@...r.kernel.org, viresh.kumar@...aro.org
Subject: [tip:timers/core] tick: sched: Remove hrtimer_active() checks

Commit-ID:  afc08b15cc2a3d2c48cbd427be8e0eea05698363
Gitweb:     http://git.kernel.org/tip/afc08b15cc2a3d2c48cbd427be8e0eea05698363
Author:     Thomas Gleixner <tglx@...utronix.de>
AuthorDate: Tue, 14 Apr 2015 21:08:52 +0000
Committer:  Thomas Gleixner <tglx@...utronix.de>
CommitDate: Wed, 22 Apr 2015 17:06:50 +0200

tick: sched: Remove hrtimer_active() checks

hrtimer_start() enforces a timer interrupt if the timer is already
expired. Get rid of the checks and the forward loop.

Signed-off-by: Thomas Gleixner <tglx@...utronix.de>
Reviewed-by: Frederic Weisbecker <fweisbec@...il.com>
Acked-by: Peter Zijlstra <peterz@...radead.org>
Cc: Preeti U Murthy <preeti@...ux.vnet.ibm.com>
Cc: Viresh Kumar <viresh.kumar@...aro.org>
Cc: Marcelo Tosatti <mtosatti@...hat.com>
Cc: John Stultz <john.stultz@...aro.org>
Cc: Marcelo Tosatti <mtosatti@...hat.com>
Link: http://lkml.kernel.org/r/20150414203501.943658239@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@...utronix.de>

---
 kernel/time/tick-sched.c | 19 ++++---------------
 1 file changed, 4 insertions(+), 15 deletions(-)

diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 9142591..dc586c3 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -696,11 +696,9 @@ static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts,
 		if (ts->nohz_mode == NOHZ_MODE_HIGHRES) {
 			hrtimer_start(&ts->sched_timer, expires,
 				      HRTIMER_MODE_ABS_PINNED);
-			/* Check, if the timer was already in the past */
-			if (hrtimer_active(&ts->sched_timer))
-				goto out;
+			goto out;
 		} else if (!tick_program_event(expires, 0))
-				goto out;
+			goto out;
 		/*
 		 * We are past the event already. So we crossed a
 		 * jiffie boundary. Update jiffies and raise the
@@ -888,8 +886,6 @@ static void tick_nohz_restart(struct tick_sched *ts, ktime_t now)
 		if (ts->nohz_mode == NOHZ_MODE_HIGHRES) {
 			hrtimer_start_expires(&ts->sched_timer,
 					      HRTIMER_MODE_ABS_PINNED);
-			/* Check, if the timer was already in the past */
-			if (hrtimer_active(&ts->sched_timer))
 				break;
 		} else {
 			if (!tick_program_event(
@@ -1167,15 +1163,8 @@ void tick_setup_sched_timer(void)
 		hrtimer_add_expires_ns(&ts->sched_timer, offset);
 	}
 
-	for (;;) {
-		hrtimer_forward(&ts->sched_timer, now, tick_period);
-		hrtimer_start_expires(&ts->sched_timer,
-				      HRTIMER_MODE_ABS_PINNED);
-		/* Check, if the timer was already in the past */
-		if (hrtimer_active(&ts->sched_timer))
-			break;
-		now = ktime_get();
-	}
+	hrtimer_forward(&ts->sched_timer, now, tick_period);
+	hrtimer_start_expires(&ts->sched_timer, HRTIMER_MODE_ABS_PINNED);
 
 #ifdef CONFIG_NO_HZ_COMMON
 	if (tick_nohz_enabled) {
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/