diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2011-07-25 17:11:57 -0700 |
|---|---|---|
| committer | Jonas ABERG <jonas.aberg@stericsson.com> | 2011-10-28 11:13:06 +0200 |
| commit | 0d19bf0cb60fa5b274eb1ab488c4b0c3e02ccb8a (patch) | |
| tree | a8f58e1a969c3171526b95fe4a45da63e013d70f | |
| parent | e30f5e6f3c5bde29835a5e3fb382ff9ba8c9bbd3 (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>
Change-Id: Iac6bcdd20e8656bc227eddb283aca3f8efd9fd1e
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/35646
Tested-by: Per VAHLNE <per.xx.vahlne@stericsson.com>
Reviewed-by: Jonas ABERG <jonas.aberg@stericsson.com>
| -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 f032e6e1e09..e56fe35cef0 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); |