From: Nicolas Pitre <nicolas.pitre@linaro.org>
To: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Sudeep Holla <sudeep.holla@arm.com>,
Peter Zijlstra <peterz@infradead.org>,
Linus Walleij <linus.walleij@linaro.org>,
Daniel Lezcano <daniel.lezcano@linaro.org>,
"Rafael J. Wysocki" <rafael@kernel.org>,
Linux PM list <linux-pm@vger.kernel.org>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@kernel.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
ACPI Devel Maling List <linux-acpi@vger.kernel.org>
Subject: Re: [PATCH][Fix] cpuidle: Run tick_broadcast_exit() with disabled interrupts
Date: Thu, 30 Apr 2015 16:12:46 -0400 (EDT) [thread overview]
Message-ID: <alpine.LFD.2.11.1504301602180.1582@knanqh.ubzr> (raw)
In-Reply-To: <2872649.RClMYKns0i@vostro.rjw.lan>
On Wed, 29 Apr 2015, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>
> Commit 335f49196fd6 (sched/idle: Use explicit broadcast oneshot
> control function) replaced clockevents_notify() invocations in
> cpuidle_idle_call() with direct calls to tick_broadcast_enter()
> and tick_broadcast_exit(), but it overlooked the fact that
> interrupts were already enabled before calling the latter which
> led to functional breakage on systems using idle states with the
> CPUIDLE_FLAG_TIMER_STOP flag set.
>
> Fix that by moving the invocations of tick_broadcast_enter()
> and tick_broadcast_exit() down into cpuidle_enter_state() where
> interrupts are still disabled when tick_broadcast_exit() is
> called. Also ensure that interrupts will be disabled before
> running tick_broadcast_exit() even if they have been enabled by
> the idle state's ->enter callback. Trigger a WARN_ON_ONCE() in
> that case, as we generally don't want that to happen for states
> with CPUIDLE_FLAG_TIMER_STOP set.
Incidentally I was debugging this issue as well when I saw this thread.
And it turns out that I did report this issue 2 months ago:
http://article.gmane.org/gmane.linux.kernel/1892049
What happened?
> Fixes: 335f49196fd6 (sched/idle: Use explicit broadcast oneshot control function)
> Reported-and-tested-by: Linus Walleij <linus.walleij@linaro.org>
> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Reported-and-tested-by: Sudeep Holla <sudeep.holla@arm.com>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Nicolas Pitre <nico@linaro.org>
> ---
>
> Thanks for the testing and ACKs, here it goes again with all tags and
> a changelog.
>
> If anything is missing/incorrect, please let me know ASAP as I'm going to
> push this to Linus in a couple of days.
>
> ---
> drivers/cpuidle/cpuidle.c | 16 ++++++++++++++++
> kernel/sched/idle.c | 16 ++--------------
> 2 files changed, 18 insertions(+), 14 deletions(-)
>
> Index: linux-pm/kernel/sched/idle.c
> ===================================================================
> --- linux-pm.orig/kernel/sched/idle.c
> +++ linux-pm/kernel/sched/idle.c
> @@ -81,7 +81,6 @@ static void cpuidle_idle_call(void)
> struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices);
> struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev);
> int next_state, entered_state;
> - unsigned int broadcast;
> bool reflect;
>
> /*
> @@ -150,17 +149,6 @@ static void cpuidle_idle_call(void)
> goto exit_idle;
> }
>
> - broadcast = drv->states[next_state].flags & CPUIDLE_FLAG_TIMER_STOP;
> -
> - /*
> - * Tell the time framework to switch to a broadcast timer
> - * because our local timer will be shutdown. If a local timer
> - * is used from another cpu as a broadcast timer, this call may
> - * fail if it is not available
> - */
> - if (broadcast && tick_broadcast_enter())
> - goto use_default;
> -
> /* Take note of the planned idle state. */
> idle_set_state(this_rq(), &drv->states[next_state]);
>
> @@ -174,8 +162,8 @@ static void cpuidle_idle_call(void)
> /* The cpu is no longer idle or about to enter idle. */
> idle_set_state(this_rq(), NULL);
>
> - if (broadcast)
> - tick_broadcast_exit();
> + if (entered_state == -EBUSY)
> + goto use_default;
>
> /*
> * Give the governor an opportunity to reflect on the outcome
> Index: linux-pm/drivers/cpuidle/cpuidle.c
> ===================================================================
> --- linux-pm.orig/drivers/cpuidle/cpuidle.c
> +++ linux-pm/drivers/cpuidle/cpuidle.c
> @@ -158,9 +158,18 @@ int cpuidle_enter_state(struct cpuidle_d
> int entered_state;
>
> struct cpuidle_state *target_state = &drv->states[index];
> + bool broadcast = !!(target_state->flags & CPUIDLE_FLAG_TIMER_STOP);
> ktime_t time_start, time_end;
> s64 diff;
>
> + /*
> + * Tell the time framework to switch to a broadcast timer because our
> + * local timer will be shut down. If a local timer is used from another
> + * CPU as a broadcast timer, this call may fail if it is not available.
> + */
> + if (broadcast && tick_broadcast_enter())
> + return -EBUSY;
> +
> trace_cpu_idle_rcuidle(index, dev->cpu);
> time_start = ktime_get();
>
> @@ -169,6 +178,13 @@ int cpuidle_enter_state(struct cpuidle_d
> time_end = ktime_get();
> trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, dev->cpu);
>
> + if (broadcast) {
> + if (WARN_ON_ONCE(!irqs_disabled()))
> + local_irq_disable();
> +
> + tick_broadcast_exit();
> + }
> +
> if (!cpuidle_state_is_coupled(dev, drv, entered_state))
> local_irq_enable();
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
>
>
next prev parent reply other threads:[~2015-04-30 20:12 UTC|newest]
Thread overview: 90+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-04-01 22:02 [PATCH 00/20] clockevents_notify() removal Rafael J. Wysocki
2015-04-01 22:03 ` [PATCH 01/20] clockevents: Provide explicit broadcast control functions Rafael J. Wysocki
2015-04-01 22:04 ` [PATCH 02/20] x86, amd_idle: Use explicit broadcast control function Rafael J. Wysocki
2015-04-01 22:05 ` [PATCH 03/20] ACPI / PAD: " Rafael J. Wysocki
2015-04-01 22:06 ` [PATCH 04/20] ACPI / processor: " Rafael J. Wysocki
2015-04-01 22:07 ` [PATCH 05/20] cpuidle: " Rafael J. Wysocki
2015-04-01 22:09 ` [PATCH 06/20] intel_idle: " Rafael J. Wysocki
2015-04-01 22:10 ` [PATCH 07/20] ARM: OMAP: " Rafael J. Wysocki
2015-04-01 22:11 ` [PATCH 08/20] clockevents: Remove the broadcast control leftovers Rafael J. Wysocki
2015-04-01 22:13 ` [PATCH 09/20] clockevents: Provide explicit broadcast oneshot control functions Rafael J. Wysocki
2015-04-01 22:15 ` [PATCH 10/20] x86, amd_idle: Use " Rafael J. Wysocki
2015-04-01 22:16 ` [PATCH 11/20] ACPI / PAD: Use explicit broadcast oneshot control function Rafael J. Wysocki
2015-04-01 22:17 ` [PATCH 12/20] ACPI / processor: Use explicit broadcast controll function Rafael J. Wysocki
2015-04-01 22:20 ` [PATCH 13/20] intel_idle: Use explicit broadcast oneshot control function Rafael J. Wysocki
2015-04-01 22:20 ` [PATCH 14/20] ARM: OMAP: " Rafael J. Wysocki
2015-04-01 22:21 ` [PATCH 15/20] ARM: tegra: " Rafael J. Wysocki
2015-04-01 22:22 ` [PATCH 16/20] sched/idle: " Rafael J. Wysocki
2015-04-28 10:11 ` Linus Walleij
2015-04-28 10:17 ` Sudeep Holla
2015-04-28 10:34 ` Daniel Lezcano
2015-04-28 10:42 ` Sudeep Holla
2015-04-28 12:19 ` Rafael J. Wysocki
2015-04-28 12:37 ` Linus Walleij
2015-04-28 13:31 ` Rafael J. Wysocki
2015-04-28 13:37 ` Rafael J. Wysocki
2015-04-28 14:14 ` Rafael J. Wysocki
2015-04-28 13:58 ` Sudeep Holla
2015-04-29 0:50 ` Rafael J. Wysocki
2015-04-29 1:04 ` Rafael J. Wysocki
2015-04-29 7:10 ` Linus Walleij
2015-04-29 8:57 ` Peter Zijlstra
2015-04-29 9:44 ` Daniel Lezcano
2015-04-29 9:50 ` Sudeep Holla
2015-04-29 14:07 ` [PATCH][Fix] cpuidle: Run tick_broadcast_exit() with disabled interrupts Rafael J. Wysocki
2015-04-30 3:47 ` Preeti U Murthy
2015-04-30 20:12 ` Nicolas Pitre [this message]
2015-04-30 22:10 ` Rafael J. Wysocki
2015-04-30 3:45 ` [PATCH 16/20] sched/idle: Use explicit broadcast oneshot control function Preeti U Murthy
2015-04-28 13:04 ` Sudeep Holla
2015-04-01 22:23 ` [PATCH 17/20] clockevents: Remove broadcast oneshot control leftovers Rafael J. Wysocki
2015-04-01 22:24 ` [PATCH 18/20] clockevents: Make tick handover explicit Rafael J. Wysocki
2015-04-01 22:25 ` [PATCH 19/20] clockevents: Cleanup dead cpu explicitely Rafael J. Wysocki
2015-04-01 22:26 ` [PATCH 20/20] timekeeping: Get rid of stale comment Rafael J. Wysocki
2015-04-01 23:57 ` John Stultz
2015-04-02 12:39 ` [PATCH 00/20] clockevents_notify() removal Ingo Molnar
2015-04-02 22:19 ` Rafael J. Wysocki
2015-04-02 23:45 ` [v2][PATCH 00/21] " Rafael J. Wysocki
2015-04-02 23:46 ` [v2][PATCH 01/21] ACPI / PAD: Remove the local APIC nonsense Rafael J. Wysocki
2015-04-03 8:21 ` [tip:timers/core] ACPI/PAD: " tip-bot for Thomas Gleixner
2015-04-03 0:01 ` [v2][PATCH 02/21] clockevents: Provide explicit broadcast control functions Rafael J. Wysocki
2015-04-03 8:21 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-03 0:01 ` [v2][PATCH 03/21] x86, amd_idle: Use explicit broadcast control function Rafael J. Wysocki
2015-04-03 8:22 ` [tip:timers/core] x86/amd/idle, clockevents: " tip-bot for Thomas Gleixner
2015-04-03 0:01 ` [v2][PATCH 04/21] ACPI / PAD: " Rafael J. Wysocki
2015-04-03 8:22 ` [tip:timers/core] ACPI/PAD: " tip-bot for Thomas Gleixner
2015-04-03 0:02 ` [v2][PATCH 05/21] ACPI / processor: " Rafael J. Wysocki
2015-04-03 8:22 ` [tip:timers/core] ACPI/processor: " tip-bot for Thomas Gleixner
2015-04-03 0:02 ` [v2][PATCH 06/21] cpuidle: " Rafael J. Wysocki
2015-04-03 8:23 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-03 0:02 ` [v2][PATCH 07/21] intel_idle: " Rafael J. Wysocki
2015-04-03 8:23 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-03 0:02 ` [v2][PATCH 08/21] ARM: OMAP: " Rafael J. Wysocki
2015-04-03 8:23 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-03 0:03 ` [v2][PATCH 09/21] clockevents: Remove the broadcast control leftovers Rafael J. Wysocki
2015-04-03 8:23 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-03 0:05 ` [v2][PATCH 10/21] clockevents: Provide explicit broadcast oneshot control functions Rafael J. Wysocki
2015-04-03 8:24 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-03 0:05 ` [v2][PATCH 11/21] x86, amd_idle: Use " Rafael J. Wysocki
2015-04-03 8:24 ` [tip:timers/core] x86/amd/idle, clockevents: " tip-bot for Thomas Gleixner
2015-04-03 0:06 ` [v2][PATCH 12/21] ACPI / PAD: Use explicit broadcast oneshot control function Rafael J. Wysocki
2015-04-03 8:24 ` [tip:timers/core] ACPI/PAD: " tip-bot for Thomas Gleixner
2015-04-03 0:12 ` [v2][PATCH 13/21] ACPI / processor: Use explicit broadcast controll function Rafael J. Wysocki
2015-04-03 8:25 ` [tip:timers/core] ACPI/idle: Use explicit broadcast control function tip-bot for Thomas Gleixner
2015-04-03 0:14 ` [v2][PATCH 14/21] intel_idle: Use explicit broadcast oneshot " Rafael J. Wysocki
2015-04-03 8:25 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-03 0:31 ` [v2][PATCH 15/21] ARM: OMAP: " Rafael J. Wysocki
2015-04-03 8:25 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-03 0:32 ` [v2][PATCH 16/21] ARM: tegra: " Rafael J. Wysocki
2015-04-03 8:25 ` [tip:timers/core] ARM: Tegra: " tip-bot for Thomas Gleixner
2015-04-03 0:34 ` [v2][PATCH 17/21] sched/idle: " Rafael J. Wysocki
2015-04-03 8:26 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-03 0:36 ` [v2][PATCH 18/21] clockevents: Remove broadcast oneshot control leftovers Rafael J. Wysocki
2015-04-03 8:26 ` [tip:timers/core] " tip-bot for Rafael J. Wysocki
2015-04-03 0:37 ` [v2][PATCH 19/21] clockevents: Make tick handover explicit Rafael J. Wysocki
2015-04-03 8:26 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-03 0:38 ` [v2][PATCH 20/21] clockevents: Cleanup dead cpu explicitely Rafael J. Wysocki
2015-04-03 8:26 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-03 0:39 ` [v2][PATCH 21/21] timekeeping: Get rid of stale comment Rafael J. Wysocki
2015-04-03 8:27 ` [tip:timers/core] " tip-bot for Thomas Gleixner
2015-04-03 6:45 ` [v2][PATCH 00/21] clockevents_notify() removal Ingo Molnar
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=alpine.LFD.2.11.1504301602180.1582@knanqh.ubzr \
--to=nicolas.pitre@linaro.org \
--cc=daniel.lezcano@linaro.org \
--cc=linus.walleij@linaro.org \
--cc=linux-acpi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=mingo@kernel.org \
--cc=peterz@infradead.org \
--cc=rafael@kernel.org \
--cc=rjw@rjwysocki.net \
--cc=sudeep.holla@arm.com \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).