A-Team_Digital_Solutions/android_kernel_motorola_sm6375
Watch
2
0
Fork
You've already forked android_kernel_motorola_sm6375
 0
mirror of https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git synced 2026-10-29 03:01:39 -04:00
Code Issues Projects Releases Packages Wiki Activity

Block: use a freezable workqueue for disk-event polling

Browse source 
This patch (as1519) fixes a bug in the block layer's disk-events
polling.  The polling is done by a work routine queued on the
system_nrt_wq workqueue.  Since that workqueue isn't freezable, the
polling continues even in the middle of a system sleep transition.

Obviously, polling a suspended drive for media changes and such isn't
a good thing to do; in the case of USB mass-storage devices it can
lead to real problems requiring device resets and even re-enumeration.

The patch fixes things by creating a new system-wide, non-reentrant,
freezable workqueue and using it for disk-events polling.

Signed-off-by: Alan Stern <[email protected]>
CC: <[email protected]>
Acked-by: Tejun Heo <[email protected]>
Acked-by: Rafael J. Wysocki <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
This commit is contained in:
Alan Stern 2012-03-02 10:51:00 +01:00 • committed by Jens Axboe
commit 62d3c5439c
3 changed files with 15 additions and 6 deletions
Download patch file Download diff file Expand all files Collapse all files

10
block/genhd.c
View file

@ -1478,9 +1478,9 @@ static void __disk_unblock_events(struct gendisk *disk, bool check_now)
intv = disk_events_poll_jiffies(disk);
set_timer_slack(&ev->dwork.timer, intv / 4);
if (check_now)
queue_delayed_work(system_nrt_wq, &ev->dwork, 0);
queue_delayed_work(system_nrt_freezable_wq, &ev->dwork, 0);
else if (intv)
queue_delayed_work(system_nrt_wq, &ev->dwork, intv);
queue_delayed_work(system_nrt_freezable_wq, &ev->dwork, intv);
out_unlock:
spin_unlock_irqrestore(&ev->lock, flags);
}
@ -1524,7 +1524,7 @@ void disk_flush_events(struct gendisk *disk, unsigned int mask)
ev->clearing |= mask;
if (!ev->block) {
cancel_delayed_work(&ev->dwork);
queue_delayed_work(system_nrt_wq, &ev->dwork, 0);
queue_delayed_work(system_nrt_freezable_wq, &ev->dwork, 0);
}
spin_unlock_irq(&ev->lock);
}
@ -1561,7 +1561,7 @@ unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask)
/* uncondtionally schedule event check and wait for it to finish */
disk_block_events(disk);
queue_delayed_work(system_nrt_wq, &ev->dwork, 0);
queue_delayed_work(system_nrt_freezable_wq, &ev->dwork, 0);
flush_delayed_work(&ev->dwork);
__disk_unblock_events(disk, false);
@ -1598,7 +1598,7 @@ static void disk_events_workfn(struct work_struct *work)
intv = disk_events_poll_jiffies(disk);
if (!ev->block && intv)
queue_delayed_work(system_nrt_wq, &ev->dwork, intv);
queue_delayed_work(system_nrt_freezable_wq, &ev->dwork, intv);
spin_unlock_irq(&ev->lock);