Re: [RFC v0 2/9] suspend: Add getter function to report if freezing is active

Rafael J. Wysocki
2015-09-05T01:43:32Z

On Friday, September 04, 2015 03:34:55 PM Daniel Wagner wrote:
> Instead encode the FREEZE state via the CPU state we allow the
> interesting subsystems (MCE, microcode) to query the power
> subsystem directly.

A use case, please.

> Most notifiers are not interested at all
> in this information so rather have explicit calls to freeze_active()
> instead adding complexity to the rest of the users of the CPU
> notifiers.

Why does it has anything to do with CPU notifiers? We don't offline
CPUs for suspend-to-idle.

> Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Cc: Len Brown <len.brown@intel.com>
> Cc: Pavel Machek <pavel@ucw.cz>
> Cc: linux-pm@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> ---
> include/linux/suspend.h | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/include/linux/suspend.h b/include/linux/suspend.h
> index 5efe743..5e15ade 100644
> --- a/include/linux/suspend.h
> +++ b/include/linux/suspend.h
> @@ -216,6 +216,11 @@ static inline bool idle_should_freeze(void)
> return unlikely(suspend_freeze_state == FREEZE_STATE_ENTER);
> }
>
> +static inline bool freeze_active(void)
> +{
> + return unlikely(suspend_freeze_state != FREEZE_STATE_NONE);
> +}
> +
> extern void freeze_set_ops(const struct platform_freeze_ops *ops);
> extern void freeze_wake(void);
>
> @@ -244,6 +249,7 @@ extern int pm_suspend(suspend_state_t state);
> static inline void suspend_set_ops(const struct platform_suspend_ops *ops) {}
> static inline int pm_suspend(suspend_state_t state) { return -ENOSYS; }
> static inline bool idle_should_freeze(void) { return false; }
> +static inline bool freeze_active(void) { return false; }
> static inline void freeze_set_ops(const struct platform_freeze_ops *ops) {}
> static inline void freeze_wake(void) {}
> #endif /* !CONFIG_SUSPEND */
>

--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.