On Wed, Jun 29, 2022 at 4:02 PM Jason A. Donenfeld <ja...@zx2c4.com> wrote:
>
> Hi Kalesh,
>
> On Wed, Jun 29, 2022 at 03:26:33PM -0700, Kalesh Singh wrote:
> > Thanks for taking a look. I'm concerned holding the sys/power/state
> > open would have unintentional side effects. Adding the
> > /sys/power/userspace_autosuspender seems more appropriate. We don't
> > have a use case for the refcounting, so would prefer the simpler
> > writing '0' / '1' to toggle semantics.
>
> Alright. So I've cooked you up some code that you can submit, since I
> assume based on Christoph's bristliness that he won't do so. The below
> adds /sys/power/pm_userspace_autosleeper, which you can write a 0 or a 1
> into, and fixes up wireguard and random.c to use it. The code is
> untested, but should generally be the correct thing, I think.
>
> So in order of operations:
>
> 1. You write a patch for SystemSuspend.cpp and post it on Gerrit.
>
> 2. You take the diff below, clean it up or bikeshed the naming a bit or
> do whatever there, and submit it to Rafael's PM tree, including as a
> `Link: ...` this thread and the Gerrit link.
>
> 3. When/if Rafael accepts the patch, you submit the Gerrit CL.
>
> 4. When both have landed, Christoph moves forward with his
> CONFIG_ANDROID removal.
>
> Does that seem like a reasonable way forward?
Sounds like a plan. I'll clean up and repost your patch once the
Gerrit change is ready.
Thanks,
Kalesh
>
> Jason
>
> diff --git a/drivers/char/random.c b/drivers/char/random.c
> index e3dd1dd3dd22..c25e3be10d9c 100644
> --- a/drivers/char/random.c
> +++ b/drivers/char/random.c
> @@ -756,7 +756,7 @@ static int random_pm_notification(struct notifier_block
> *nb, unsigned long actio
>
> if (crng_ready() && (action == PM_RESTORE_PREPARE ||
> (action == PM_POST_SUSPEND &&
> - !IS_ENABLED(CONFIG_PM_AUTOSLEEP) &&
> !IS_ENABLED(CONFIG_ANDROID)))) {
> + !IS_ENABLED(CONFIG_PM_AUTOSLEEP) &&
> !pm_userspace_autosleeper_enabled))) {
> crng_reseed();
> pr_notice("crng reseeded on system resumption\n");
> }
> diff --git a/drivers/net/wireguard/device.c b/drivers/net/wireguard/device.c
> index aa9a7a5970fd..1983e0fadb6e 100644
> --- a/drivers/net/wireguard/device.c
> +++ b/drivers/net/wireguard/device.c
> @@ -69,7 +69,7 @@ static int wg_pm_notification(struct notifier_block *nb,
> unsigned long action, v
> * its normal operation rather than as a somewhat rare event, then we
> * don't actually want to clear keys.
> */
> - if (IS_ENABLED(CONFIG_PM_AUTOSLEEP) || IS_ENABLED(CONFIG_ANDROID))
> + if (IS_ENABLED(CONFIG_PM_AUTOSLEEP) ||
> pm_userspace_autosleeper_enabled)
> return 0;
>
> if (action != PM_HIBERNATION_PREPARE && action != PM_SUSPEND_PREPARE)
> diff --git a/include/linux/suspend.h b/include/linux/suspend.h
> index 70f2921e2e70..0acff26f87b4 100644
> --- a/include/linux/suspend.h
> +++ b/include/linux/suspend.h
> @@ -498,6 +498,7 @@ extern void ksys_sync_helper(void);
> /* drivers/base/power/wakeup.c */
> extern bool events_check_enabled;
> extern suspend_state_t pm_suspend_target_state;
> +extern bool pm_userspace_autosleeper_enabled;
>
> extern bool pm_wakeup_pending(void);
> extern void pm_system_wakeup(void);
> @@ -537,6 +538,8 @@ static inline void pm_system_irq_wakeup(unsigned int
> irq_number) {}
> static inline void lock_system_sleep(void) {}
> static inline void unlock_system_sleep(void) {}
>
> +#define pm_userspace_autosleeper_enabled (false)
> +
> #endif /* !CONFIG_PM_SLEEP */
>
> #ifdef CONFIG_PM_SLEEP_DEBUG
> diff --git a/kernel/power/main.c b/kernel/power/main.c
> index e3694034b753..08f32a281010 100644
> --- a/kernel/power/main.c
> +++ b/kernel/power/main.c
> @@ -120,6 +120,23 @@ static ssize_t pm_async_store(struct kobject *kobj,
> struct kobj_attribute *attr,
>
> power_attr(pm_async);
>
> +bool pm_userspace_autosleeper_enabled;
> +
> +static ssize_t pm_userspace_autosleeper_show(struct kobject *kobj,
> + struct kobj_attribute *attr, char *buf)
> +{
> + return sprintf(buf, "%d\n", pm_userspace_autosleeper_enabled);
> +}
> +
> +static ssize_t pm_userspace_autosleeper_store(struct kobject *kobj,
> + struct kobj_attribute *attr,
> + const char *buf, size_t n)
> +{
> + return kstrtobool(buf, &pm_userspace_autosleeper_enabled);
> +}
> +
> +power_attr(pm_userspace_autosleeper);
> +
> #ifdef CONFIG_SUSPEND
> static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute
> *attr,
> char *buf)
> @@ -869,6 +886,7 @@ static struct attribute * g[] = {
> #ifdef CONFIG_PM_SLEEP
> &pm_async_attr.attr,
> &wakeup_count_attr.attr,
> + &pm_userspace_autosleeper.attr,
> #ifdef CONFIG_SUSPEND
> &mem_sleep_attr.attr,
> &sync_on_suspend_attr.attr,
>
