From: Thomas Gleixner <tglx@linutronix.de>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Paul McKenney <paulmck@linux.vnet.ibm.com>,
Frederic Weisbecker <fweisbec@gmail.com>,
Eric Dumazet <edumazet@google.com>,
Viresh Kumar <viresh.kumar@linaro.org>,
John Stultz <john.stultz@linaro.org>,
Joonwoo Park <joonwoop@codeaurora.org>,
Wenbo Wang <wenbo.wang@memblaze.com>
Subject: [patch 2/7] timer: Remove FIFO guarantee
Date: Tue, 26 May 2015 22:50:26 -0000 [thread overview]
Message-ID: <20150526224511.757520403@linutronix.de> (raw)
In-Reply-To: 20150526210723.245729529@linutronix.de
[-- Attachment #1: timer-remove-fifo-guarantee.patch --]
[-- Type: text/plain, Size: 968 bytes --]
The FIFO guarantee has been violated by the introduction of timer
slack already. Remove it.
This is a preparatory patch for converting the timer wheel to hlist
which reduces the memory foot print of the wheel by 50%. It's a
seperate patch so any (unlikely to happen) regression caused by this
can be identified clearly.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
kernel/time/timer.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
Index: tip/kernel/time/timer.c
===================================================================
--- tip.orig/kernel/time/timer.c
+++ tip/kernel/time/timer.c
@@ -403,10 +403,8 @@ __internal_add_timer(struct tvec_base *b
i = (expires >> (TVR_BITS + 3 * TVN_BITS)) & TVN_MASK;
vec = base->tv5.vec + i;
}
- /*
- * Timers are FIFO:
- */
- list_add_tail(&timer->entry, vec);
+
+ list_add(&timer->entry, vec);
}
static void internal_add_timer(struct tvec_base *base, struct timer_list *timer)
next prev parent reply other threads:[~2015-05-26 22:50 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-05-26 22:50 [patch 0/7] timers: Footprint diet and NOHZ overhead mitigation Thomas Gleixner
2015-05-26 22:50 ` [patch 1/7] timers: Sanitize catchup_timer_jiffies() usage Thomas Gleixner
2015-05-27 5:39 ` Viresh Kumar
2015-06-19 13:22 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-05-26 22:50 ` Thomas Gleixner [this message]
2015-05-27 9:11 ` [patch 2/7] timer: Remove FIFO guarantee Viresh Kumar
2015-06-19 13:22 ` [tip:timers/core] timer: Remove FIFO "guarantee" tip-bot for Thomas Gleixner
2015-05-26 22:50 ` [patch 3/7] timer: Use hlist for the timer wheel hash buckets Thomas Gleixner
2015-05-27 9:13 ` Viresh Kumar
2015-06-19 13:23 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-05-26 22:50 ` [patch 4/7] timer: Replace timer base by a cpu index Thomas Gleixner
2015-05-27 9:22 ` Viresh Kumar
2015-05-27 12:09 ` Peter Zijlstra
2015-06-02 13:58 ` Thomas Gleixner
2015-06-19 13:23 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-06-27 9:55 ` [PATCH] timer: Fix unsafe cpu variable access in migrate_timers Jan Kiszka
2015-06-27 11:00 ` Borislav Petkov
2015-06-27 11:19 ` Jan Kiszka
2015-06-27 11:25 ` Borislav Petkov
2015-05-26 22:50 ` [patch 5/7] timer: stats: Simplify the flags handling Thomas Gleixner
2015-06-19 13:23 ` [tip:timers/core] timer: Stats: " tip-bot for Thomas Gleixner
2015-05-26 22:50 ` [patch 6/7] timer: Reduce timer migration overhead if disabled Thomas Gleixner
2015-06-19 13:23 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-05-26 22:50 ` [patch 7/7] timer: Minimize nohz off overhead Thomas Gleixner
2015-06-19 13:24 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-05-27 14:53 ` [patch 0/7] timers: Footprint diet and NOHZ overhead mitigation Eric Dumazet
2015-06-02 13:58 ` Thomas Gleixner
-- strict thread matches above, loose matches on Subject: below --
2015-06-05 22:27 [patch 2/7] timer: Remove FIFO guarantee George Spelvin
2015-06-08 17:48 ` Thomas Gleixner
2015-06-09 5:39 ` George Spelvin
2015-06-09 8:05 ` Thomas Gleixner
2015-06-09 9:43 ` George Spelvin
2015-06-09 10:24 ` Peter Zijlstra
2015-06-09 11:15 ` George Spelvin
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