md/bitmap: make _page_attr bitops atomic.
authorNeilBrown <neilb@suse.de>
Tue, 22 May 2012 03:55:22 +0000 (13:55 +1000)
committerNeilBrown <neilb@suse.de>
Tue, 22 May 2012 03:55:22 +0000 (13:55 +1000)
commitbdfd1140731a67c74fd74814f222c8078171adcd
treee244aa26d983b56c61fb8d53eb9a1a4105476a85
parentfae7d326cd0905624c173337fdfcfe9b86b9e6e2
md/bitmap: make _page_attr bitops atomic.

Using e.g. set_bit instead of __set_bit and using test_and_clear_bit
allow us to remove some locking and contract other locked ranges.

It is rare that we set or clear a lot of these bits, so gain should
outweigh any cost.

Signed-off-by: NeilBrown <neilb@suse.de>
drivers/md/bitmap.c