PM / Domains: Queue up power off work only if it is not pending

In theory it is possible that pm_genpd_poweroff() for two different
subdomains of the same parent domain will attempt to queue up the
execution of pm_genpd_poweroff() for the parent twice in a row.  This
would lead to unpleasant consequences, so prevent it from happening
by checking if genpd->power_off_work is pending before attempting to
queue it up.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
This commit is contained in:
Rafael J. Wysocki 2011-07-12 00:40:03 +02:00
parent 4ecd6e651d
commit 56375fd420

View File

@ -212,6 +212,19 @@ static bool genpd_abort_poweroff(struct generic_pm_domain *genpd)
return genpd->status == GPD_STATE_ACTIVE || genpd->resume_count > 0;
}
/**
* genpd_queue_power_off_work - Queue up the execution of pm_genpd_poweroff().
* @genpd: PM domait to power off.
*
* Queue up the execution of pm_genpd_poweroff() unless it's already been done
* before.
*/
static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
{
if (!work_pending(&genpd->power_off_work))
queue_work(pm_wq, &genpd->power_off_work);
}
/**
* pm_genpd_poweroff - Remove power from a given PM domain.
* @genpd: PM domain to power down.
@ -304,7 +317,7 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd)
if (parent) {
genpd_sd_counter_dec(parent);
if (parent->sd_count == 0)
queue_work(pm_wq, &parent->power_off_work);
genpd_queue_power_off_work(parent);
genpd_release_lock(parent);
}