From: Peter Zijlstra <peterz@infradead.org>
To: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Alan Cox <alan@linux.intel.com>,
"Li, Aubrey" <aubrey.li@linux.intel.com>,
LKML <linux-kernel@vger.kernel.org>,
Linux PM list <linux-pm@vger.kernel.org>,
ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
Kristen Carlson Accardi <kristen@linux.intel.com>,
John Stultz <john.stultz@linaro.org>,
Len Brown <len.brown@intel.com>
Subject: Re: [PATCH 4/6] PM / sleep: Make it possible to quiesce timers during suspend-to-idle
Date: Thu, 12 Feb 2015 14:24:47 +0100 [thread overview]
Message-ID: <20150212132447.GX23123@twins.programming.kicks-ass.net> (raw)
In-Reply-To: <3761728.YL7DDdWRW2@vostro.rjw.lan>
On Wed, Feb 11, 2015 at 05:03:44AM +0100, Rafael J. Wysocki wrote:
> Index: linux-pm/include/linux/cpuidle.h
> ===================================================================
> --- linux-pm.orig/include/linux/cpuidle.h
> +++ linux-pm/include/linux/cpuidle.h
> @@ -50,6 +50,10 @@ struct cpuidle_state {
> int index);
>
> int (*enter_dead) (struct cpuidle_device *dev, int index);
Do we want a comment here describing that enter_freeze() must not
re-enable interrupts _ever_?
To help people who want to enable this on their platform.
> +
> + void (*enter_freeze) (struct cpuidle_device *dev,
> + struct cpuidle_driver *drv,
> + int index);
> };
> +static void enter_freeze_proper(struct cpuidle_driver *drv,
> + struct cpuidle_device *dev, int index)
> +{
> + tick_freeze();
> + /*
> + * The state used here cannot be a "coupled" one, because the "coupled"
> + * cpuidle mechanism enables interrupts and doing that with timekeeping
> + * suspended is generally unsafe.
> + */
> + drv->states[index].enter_freeze(dev, drv, index);
WARN_ON(!irqs_disabled());
To go along with the comment and catch fail?
> + /*
> + * timekeeping_resume() that will be called by tick_unfreeze() for the
> + * last CPU executing it calls functions containing RCU read-side
> + * critical sections, so tell RCU about that.
> + */
> + RCU_NONIDLE(tick_unfreeze());
> +}
next prev parent reply other threads:[~2015-02-12 13:24 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-02-11 4:00 [PATCH 0/6] PM / sleep: Support for quiescing timers during suspend-to-idle Rafael J. Wysocki
2015-02-11 4:01 ` [PATCH 1/6] PM / sleep: Re-implement suspend-to-idle handling Rafael J. Wysocki
2015-02-12 13:14 ` Peter Zijlstra
2015-02-12 16:18 ` Rafael J. Wysocki
2015-02-12 22:33 ` [Update][PATCH 1/6 v2] " Rafael J. Wysocki
2015-02-11 4:01 ` [PATCH 2/6] timekeeping: Pass readout base to update_fast_timekeeper() Rafael J. Wysocki
2015-02-13 0:29 ` John Stultz
2015-02-11 4:03 ` [PATCH 3/6] timekeeping: Make it safe to use the fast timekeeper while suspended Rafael J. Wysocki
2015-02-13 0:53 ` John Stultz
2015-02-13 2:03 ` Rafael J. Wysocki
2015-02-13 2:59 ` Travis
2015-02-13 9:03 ` John Stultz
2015-02-13 14:32 ` Rafael J. Wysocki
2015-02-14 17:30 ` John Stultz
2015-02-11 4:03 ` [PATCH 4/6] PM / sleep: Make it possible to quiesce timers during suspend-to-idle Rafael J. Wysocki
2015-02-12 13:24 ` Peter Zijlstra [this message]
2015-02-12 16:19 ` Rafael J. Wysocki
2015-02-12 22:36 ` [Update][PATCH 4/6 v2] " Rafael J. Wysocki
2015-02-11 4:04 ` [PATCH 5/6] intel_idle: Add ->enter_freeze callbacks Rafael J. Wysocki
2015-02-12 13:26 ` Peter Zijlstra
2015-02-12 16:24 ` Rafael J. Wysocki
2015-02-12 16:25 ` Peter Zijlstra
2015-03-04 23:50 ` Li, Aubrey
2015-03-05 0:18 ` Rafael J. Wysocki
2015-03-05 0:09 ` Li, Aubrey
2015-02-11 4:04 ` [PATCH 6/6] ACPI / idle: Implement ->enter_freeze callback routine Rafael J. Wysocki
2015-02-13 8:13 ` [PATCH 0/6] PM / sleep: Support for quiescing timers during suspend-to-idle Peter Zijlstra
2015-02-13 14:29 ` Rafael J. Wysocki
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