linux/kernel/power
Srivatsa S. Bhat 379e0be812 PM / Freezer: Thaw only kernel threads if freezing of kernel threads fails
If freezing of kernel threads fails, we are expected to automatically
thaw tasks in the error recovery path. However, at times, we encounter
situations in which we would like the automatic error recovery path
to thaw only the kernel threads, because we want to be able to do
some more cleanup before we thaw userspace. Something like:

error = freeze_kernel_threads();
if (error) {
	/* Do some cleanup */

	/* Only then thaw userspace tasks*/
	thaw_processes();
}

An example of such a situation is where we freeze/thaw filesystems
during suspend/hibernation. There, if freezing of kernel threads
fails, we would like to thaw the frozen filesystems before thawing
the userspace tasks.

So, modify freeze_kernel_threads() to thaw only kernel threads in
case of freezing failure. And change suspend_freeze_processes()
accordingly. (At the same time, let us also get rid of the rather
cryptic usage of the conditional operator (:?) in that function.)

[rjw: In fact, this patch fixes a regression introduced during the
 3.3 merge window, because without it thaw_processes() may be called
 before swsusp_free() in some situations and that may lead to massive
 memory allocation failures.]

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Nigel Cunningham <nigel@tuxonice.net>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-04 22:23:05 +01:00
..
Kconfig
Makefile
block_io.c
console.c
hibernate.c PM / Sleep: Replace mutex_[un]lock(&pm_mutex) with [un]lock_system_sleep() 2011-12-08 23:22:29 +01:00
main.c PM / Sleep: Replace mutex_[un]lock(&pm_mutex) with [un]lock_system_sleep() 2011-12-08 23:22:29 +01:00
power.h PM / Freezer: Thaw only kernel threads if freezing of kernel threads fails 2012-02-04 22:23:05 +01:00
poweroff.c
process.c PM / Freezer: Thaw only kernel threads if freezing of kernel threads fails 2012-02-04 22:23:05 +01:00
qos.c
snapshot.c PM / Hibernate: Correct additional pages number calculation 2012-01-19 23:23:10 +01:00
suspend.c PM / Sleep: Replace mutex_[un]lock(&pm_mutex) with [un]lock_system_sleep() 2011-12-08 23:22:29 +01:00
suspend_test.c
swap.c PM / Hibernate: Drop the check of swap space size for compressed image 2012-01-14 00:41:37 +01:00
user.c PM / Hibernate: Thaw kernel threads in SNAPSHOT_CREATE_IMAGE ioctl path 2012-02-01 22:16:36 +01:00