From: Thomas Gleixner <tglx@linutronix.de>
To: Haris Okanovic <haris.okanovic@ni.com>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org,
julia.cartwright@ni.com, gratian.crisan@ni.com
Subject: Re: [PATCH] Revert "timers: Don't wake ktimersoftd on every tick"
Date: Fri, 26 May 2017 21:49:29 +0200 (CEST) [thread overview]
Message-ID: <alpine.DEB.2.20.1705262147510.2137@nanos> (raw)
In-Reply-To: <faa23f3e-28c0-6de1-66a6-2b6ab5e99462@ni.com>
On Fri, 26 May 2017, Haris Okanovic wrote:
> Anna-Maria,
>
> Look-ahead is implemented by tick_find_expired() and expiry by __run_timers(),
> both of which hold timer_base::lock (raw spin lock) while running. Those two
> routines shouldn't be able to run simultaneously on the same timer_base. Are
> you sure the race isn't in another code path?
It happens when softirq runs and drops the spinlock to call the timer
function. And from there stuff goes down the drain.
Anna-Maria will send you the test case on monday.
Thanks,
tglx
next prev parent reply other threads:[~2017-05-26 19:49 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-12-13 21:44 [RFC v2] timers: Don't wake ktimersoftd on every tick Haris Okanovic
2016-12-23 17:28 ` Sebastian Andrzej Siewior
2016-12-28 18:06 ` Haris Okanovic
2017-02-03 16:51 ` Sebastian Andrzej Siewior
2017-02-03 18:21 ` [PATCH] " Haris Okanovic
2017-02-10 17:02 ` Sebastian Andrzej Siewior
2017-05-26 17:16 ` [PATCH] Revert "timers: Don't wake ktimersoftd on every tick" Anna-Maria Gleixner
2017-05-26 19:27 ` Haris Okanovic
2017-05-26 19:49 ` Thomas Gleixner [this message]
2017-05-26 20:25 ` Haris Okanovic
2017-05-26 20:50 ` Thomas Gleixner
2017-06-02 14:37 ` Haris Okanovic
2017-06-04 14:17 ` Thomas Gleixner
2017-07-17 21:58 ` Haris Okanovic
2017-07-17 22:04 ` [PATCH v2] timers: Don't wake ktimersoftd on every tick Haris Okanovic
2017-07-18 21:33 ` Thomas Gleixner
2017-08-03 21:04 ` Haris Okanovic
2017-08-03 21:06 ` [PATCH v3 1/2] " Haris Okanovic
2017-08-03 21:06 ` [PATCH v3 2/2] timers: Don't search for expired timers while TIMER_SOFTIRQ is scheduled Haris Okanovic
2018-01-05 19:37 ` Haris Okanovic
2018-03-01 15:49 ` Haris Okanovic
2018-03-01 15:54 ` Thomas Gleixner
2018-03-01 16:35 ` Haris Okanovic
2018-03-01 16:47 ` Sebastian Andrzej Siewior
2018-03-01 18:37 ` Haris Okanovic
2018-03-01 19:06 ` Sebastian Andrzej Siewior
2018-03-02 14:52 ` Sebastian Andrzej Siewior
2018-03-02 16:29 ` Haris Okanovic
2018-03-02 16:39 ` Sebastian Andrzej Siewior
2018-03-02 17:19 ` Haris Okanovic
2018-03-06 23:39 ` [PATCH v4 1/2] timers: Don't wake ktimersoftd on every tick Haris Okanovic
2018-03-06 23:39 ` [PATCH v4 2/2] timers: Don't search for expired timers while TIMER_SOFTIRQ is scheduled Haris Okanovic
[not found] ` <1523332961.4827.1.camel@gmx.de>
2018-04-12 15:00 ` [PATCH v4 1/2] timers: Don't wake ktimersoftd on every tick Haris Okanovic
2018-06-19 12:43 ` Daniel Bristot de Oliveira
2018-06-20 14:24 ` Haris Okanovic
2018-06-28 16:36 ` Haris Okanovic
2018-06-28 16:40 ` [PATCH v5 " Haris Okanovic
2018-06-28 16:40 ` [PATCH v5 2/2] timers: Don't search for expired timers while TIMER_SOFTIRQ is scheduled Haris Okanovic
2018-07-13 12:01 ` [PATCH v5 1/2] timers: Don't wake ktimersoftd on every tick Anna-Maria Gleixner
2018-07-13 14:37 ` Haris Okanovic
2017-05-27 7:47 ` [PATCH] Revert "timers: Don't wake ktimersoftd on every tick" Sebastian Andrzej Siewior
2017-02-03 18:27 ` [RFC v2] timers: Don't wake ktimersoftd on every tick Haris Okanovic
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