diff options
| author | Domenico Andreoli <domenico.andreoli@linux.com> | 2020-05-07 09:19:52 +0200 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2020-05-19 17:48:08 +0200 |
| commit | ab7e9b067f3d9cbec28cfca51d341efb421b7a51 (patch) | |
| tree | 945ac12fc98f52d44b7f44bff01837cd62b9eb3e /kernel/power/hibernate.c | |
| parent | 3a4ccdb92e1e0f51844c8b60f2c0f48a4a620000 (diff) | |
PM: hibernate: Incorporate concurrency handling
Hibernation concurrency handling is currently delegated to user.c,
where it's also used for regulating the access to the snapshot device.
In the prospective of making user.c a separate configuration option,
such mutual exclusion is brought into hibernate.c and made available
through accessor helpers hereby introduced.
Signed-off-by: Domenico Andreoli <domenico.andreoli@linux.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'kernel/power/hibernate.c')
| -rw-r--r-- | kernel/power/hibernate.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 30bd28d1d418..02ec716a4927 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -67,6 +67,18 @@ bool freezer_test_done; static const struct platform_hibernation_ops *hibernation_ops; +static atomic_t hibernate_atomic = ATOMIC_INIT(1); + +bool hibernate_acquire(void) +{ + return atomic_add_unless(&hibernate_atomic, -1, 0); +} + +void hibernate_release(void) +{ + atomic_inc(&hibernate_atomic); +} + bool hibernation_available(void) { return nohibernate == 0 && !security_locked_down(LOCKDOWN_HIBERNATION); @@ -704,7 +716,7 @@ int hibernate(void) lock_system_sleep(); /* The snapshot device should not be opened while we're running */ - if (!atomic_add_unless(&snapshot_device_available, -1, 0)) { + if (!hibernate_acquire()) { error = -EBUSY; goto Unlock; } @@ -775,7 +787,7 @@ int hibernate(void) Exit: __pm_notifier_call_chain(PM_POST_HIBERNATION, nr_calls, NULL); pm_restore_console(); - atomic_inc(&snapshot_device_available); + hibernate_release(); Unlock: unlock_system_sleep(); pr_info("hibernation exit\n"); @@ -880,7 +892,7 @@ static int software_resume(void) goto Unlock; /* The snapshot device should not be opened while we're running */ - if (!atomic_add_unless(&snapshot_device_available, -1, 0)) { + if (!hibernate_acquire()) { error = -EBUSY; swsusp_close(FMODE_READ); goto Unlock; @@ -911,7 +923,7 @@ static int software_resume(void) __pm_notifier_call_chain(PM_POST_RESTORE, nr_calls, NULL); pm_restore_console(); pr_info("resume failed (%d)\n", error); - atomic_inc(&snapshot_device_available); + hibernate_release(); /* For success case, the suspend path will release the lock */ Unlock: mutex_unlock(&system_transition_mutex); |