Re: [PATCH 1/6] Hibernation: Introduce system_entering_hibernation

From: Frederic Weisbecker
Date: Mon Jan 19 2009 - 16:25:42 EST


On Mon, Jan 19, 2009 at 08:54:54PM +0100, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rjw@xxxxxxx>
>
> Introduce boolean function system_entering_hibernation() returning
> 'true' during the last phase of hibernation, in which devices are
> being put into low power states and the sleep state (for example,
> ACPI S4) is finally entered.
>
> Some device drivers need such a function to check if the system is
> in the final phase of hibernation. In particular, some SATA drivers
> are going to use it for blacklisting systems in which the disks
> should not be spun down during the last phase of hibernation (the
> BIOS will do that anyway).
>

Hi Rafael,

Why not using the power event notifier?

Frederic.


> Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx>
> ---
> include/linux/suspend.h | 2 ++
> kernel/power/disk.c | 10 ++++++++++
> 2 files changed, 12 insertions(+)
>
> Index: linux-2.6/include/linux/suspend.h
> ===================================================================
> --- linux-2.6.orig/include/linux/suspend.h
> +++ linux-2.6/include/linux/suspend.h
> @@ -237,6 +237,7 @@ extern int hibernate_nvs_alloc(void);
> extern void hibernate_nvs_free(void);
> extern void hibernate_nvs_save(void);
> extern void hibernate_nvs_restore(void);
> +extern bool system_entering_hibernation(void);
> #else /* CONFIG_HIBERNATION */
> static inline int swsusp_page_is_forbidden(struct page *p) { return 0; }
> static inline void swsusp_set_page_free(struct page *p) {}
> @@ -252,6 +253,7 @@ static inline int hibernate_nvs_alloc(vo
> static inline void hibernate_nvs_free(void) {}
> static inline void hibernate_nvs_save(void) {}
> static inline void hibernate_nvs_restore(void) {}
> +static inline bool system_entering_hibernation(void) { return false; }
> #endif /* CONFIG_HIBERNATION */
>
> #ifdef CONFIG_PM_SLEEP
> Index: linux-2.6/kernel/power/disk.c
> ===================================================================
> --- linux-2.6.orig/kernel/power/disk.c
> +++ linux-2.6/kernel/power/disk.c
> @@ -71,6 +71,14 @@ void hibernation_set_ops(struct platform
> mutex_unlock(&pm_mutex);
> }
>
> +static bool entering_platform_hibernation;
> +
> +bool system_entering_hibernation(void)
> +{
> + return entering_platform_hibernation;
> +}
> +EXPORT_SYMBOL(system_entering_hibernation);
> +
> #ifdef CONFIG_PM_DEBUG
> static void hibernation_debug_sleep(void)
> {
> @@ -411,6 +419,7 @@ int hibernation_platform_enter(void)
> if (error)
> goto Close;
>
> + entering_platform_hibernation = true;
> suspend_console();
> error = device_suspend(PMSG_HIBERNATE);
> if (error) {
> @@ -445,6 +454,7 @@ int hibernation_platform_enter(void)
> Finish:
> hibernation_ops->finish();
> Resume_devices:
> + entering_platform_hibernation = false;
> device_resume(PMSG_RESTORE);
> resume_console();
> Close:
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/