On Mon, 23 Apr 2012, Joe Thornber wrote: > On Wed, Apr 18, 2012 at 11:03:33PM -0400, Mikulas Patocka wrote: > > Hi > > > > I placed dm lock optimization patches here > > > > http://people.redhat.com/mpatocka/patches/kernel/dm-lock-optimization/ > > Just a heads up that sparse gives some warnings with these patches: > > drivers/md/dm.c:689:24: warning: context imbalance in 'dm_get_live_table_fast' - wrong count at exit > drivers/md/dm.c:695:13: warning: context imbalance in 'dm_put_live_table_fast' - unexpected unlock > drivers/md/dm.c:1789:17: warning: context imbalance in 'dm_request_fn' - unexpected unlock > > - Joe I couldn't figure out how to shut up sparse warnings. For RCU you can mark functions that take/release RCU with __acquires(RCU)/__releases(RCU), but I didn't find out how to do it for SRCU. If I use "__acquires(&md->io_barrier)" struct dm_table *dm_get_live_table(struct mapped_device *md, int *srcu_idx) __acquires(&md->io_barrier) { *srcu_idx = srcu_read_lock(&md->io_barrier); return rcu_dereference(md->map); } it doens't work and I get an error: drivers/md/dm.c:557:9: warning: context imbalance in 'dm_get_live_table': unexpected unlock drivers/md/dm.c:557:9: default context: wanted 1, got 0 Maybe it is a bug in sparse, maybe I am using a wrong tag? Is there a reference of all sparse tags somewhere? Mikulas -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
