diff options
| author | Jonathan Brassow <jbrassow@redhat.com> | 2007-07-12 20:28:25 +0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-07-13 02:01:08 +0400 |
| commit | 943317efdbc295e8a28df3f5cbd549d066ee8b4a (patch) | |
| tree | 63eea4f14c4b3913b6755d802afb7631007a9e0e /drivers/md | |
| parent | 0764147b111b8ca886e4f2e9c9e019106b09b657 (diff) | |
| download | linux-943317efdbc295e8a28df3f5cbd549d066ee8b4a.tar.xz | |
dm raid1: clear region outside spinlock
A clear_region function is permitted to block (in practice, rare) but gets
called in rh_update_states() with a spinlock held.
The bits being marked and cleared by the above functions are used
to update the on-disk log, but are never read directly. We can
perform these operations outside the spinlock since the
bits are only changed within one thread viz.
- mark_region in rh_inc()
- clear_region in rh_update_states().
So, we grab the clean_regions list items via list_splice() within the
spinlock and defer clear_region() until we iterate over the list for
deletion - similar to how the recovered_regions list is already handled.
We then move the flush() call down to ensure it encapsulates the changes
which are done by the later calls to clear_region().
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/dm-raid1.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c index b3bba98af772..04dce7a66494 100644 --- a/drivers/md/dm-raid1.c +++ b/drivers/md/dm-raid1.c @@ -378,10 +378,8 @@ static void rh_update_states(struct region_hash *rh) list_splice(&rh->clean_regions, &clean); INIT_LIST_HEAD(&rh->clean_regions); - list_for_each_entry (reg, &clean, list) { - rh->log->type->clear_region(rh->log, reg->key); + list_for_each_entry(reg, &clean, list) list_del(®->hash_list); - } } if (!list_empty(&rh->recovered_regions)) { @@ -405,10 +403,12 @@ static void rh_update_states(struct region_hash *rh) mempool_free(reg, rh->region_pool); } - rh->log->type->flush(rh->log); - - list_for_each_entry_safe (reg, next, &clean, list) + list_for_each_entry_safe(reg, next, &clean, list) { + rh->log->type->clear_region(rh->log, reg->key); mempool_free(reg, rh->region_pool); + } + + rh->log->type->flush(rh->log); } static void rh_inc(struct region_hash *rh, region_t region) |