diff options
| author | Arve Hjønnevåg <arve@android.com> | 2010-05-24 20:35:11 +0200 |
|---|---|---|
| committer | Rafael J. Wysocki <rjw@sisk.pl> | 2010-05-24 20:35:11 +0200 |
| commit | b36d6886dbebf48626bf27effe36fb4e70601b5d (patch) | |
| tree | 426ec68295e86482452ada35f5a98da0c4ebf1e2 /kernel | |
| parent | 4965b20bd331ac061c466472e923b3fd70452928 (diff) | |
PM: Abort task freezing if there is an active suspend blocker
If a suspend_blocker is active, suspend will fail anyway. Since
try_to_freeze_tasks can take up to 20 seconds to complete or fail,
aborting as soon as someone blocks suspend (e.g. from an interrupt
handler) improves the worst case wakeup latency.
On an older kernel where task freezing could fail for processes
attached to a debugger, this fixed a problem where the device
sometimes hung for 20 seconds before the screen turned on.
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/power/process.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/kernel/power/process.c b/kernel/power/process.c index 71ae29052ab6..27d26d3eb748 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -38,6 +38,7 @@ static int try_to_freeze_tasks(bool sig_only) struct timeval start, end; u64 elapsed_csecs64; unsigned int elapsed_csecs; + bool wakeup = false; do_gettimeofday(&start); @@ -63,6 +64,10 @@ static int try_to_freeze_tasks(bool sig_only) todo++; } while_each_thread(g, p); read_unlock(&tasklist_lock); + if (todo && suspend_is_blocked()) { + wakeup = true; + break; + } if (!todo || time_after(jiffies, end_time)) break; @@ -85,13 +90,15 @@ static int try_to_freeze_tasks(bool sig_only) * but it cleans up leftover PF_FREEZE requests. */ printk("\n"); - printk(KERN_ERR "Freezing of tasks failed after %d.%02d seconds " + printk(KERN_ERR "Freezing of tasks %s after %d.%02d seconds " "(%d tasks refusing to freeze):\n", + wakeup ? "aborted" : "failed", elapsed_csecs / 100, elapsed_csecs % 100, todo); read_lock(&tasklist_lock); do_each_thread(g, p) { task_lock(p); - if (freezing(p) && !freezer_should_skip(p)) + if (freezing(p) && !freezer_should_skip(p) + && elapsed_csecs > 100) sched_show_task(p); cancel_freezing(p); task_unlock(p); |