diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2011-07-25 17:11:57 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-08-04 21:58:39 -0700 |
| commit | 650957da7699e730e78e82735b8c2595fcf7794a (patch) | |
| tree | 1f44a3a822a79e5f89eb6c71427d2576a087e7d5 /mm | |
| parent | b045b9a265fb46d8197b7d78aff1a8f6ab8e23df (diff) | |
mm/backing-dev.c: reset bdi min_ratio in bdi_unregister()
commit ccb6108f5b0b541d3eb332c3a73e645c0f84278e upstream.
Vito said:
: The system has many usb disks coming and going day to day, with their
: respective bdi's having min_ratio set to 1 when inserted. It works for
: some time until eventually min_ratio can no longer be set, even when the
: active set of bdi's seen in /sys/class/bdi/*/min_ratio doesn't add up to
: anywhere near 100.
:
: This then leads to an unrelated starvation problem caused by write-heavy
: fuse mounts being used atop the usb disks, a problem the min_ratio setting
: at the underlying devices bdi effectively prevents.
Fix this leakage by resetting the bdi min_ratio when unregistering the
BDI.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Reported-by: Vito Caputo <lkml@pengaru.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/backing-dev.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/mm/backing-dev.c b/mm/backing-dev.c index f032e6e1e09a..e56fe35cef05 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -606,6 +606,7 @@ static void bdi_prune_sb(struct backing_dev_info *bdi) void bdi_unregister(struct backing_dev_info *bdi) { if (bdi->dev) { + bdi_set_min_ratio(bdi, 0); trace_writeback_bdi_unregister(bdi); bdi_prune_sb(bdi); del_timer_sync(&bdi->wb.wakeup_timer); |