tree 12087e87fb8d41d10013946e5b2c91e57265c29e
parent 2bf0fdad51c6710bf15d0bf4b9b30b8498fe4ddd
author Tejun Heo <htejun@gmail.com> 1119510529 -0700
committer Linus Torvalds <torvalds@ppc970.osdl.org> 1119545115 -0700

[PATCH] blk: remove blk_queue_tag->real_max_depth optimization

blk_queue_tag->real_max_depth was used to optimize out unnecessary
allocations/frees on tag resize.  However, the whole thing was very broken -
tag_map was never allocated to real_max_depth resulting in access beyond the
end of the map, bits in [max_depth..real_max_depth] were set when initializing
a map and copied when resizing resulting in pre-occupied tags.

As the gain of the optimization is very small, well, almost nill, remove the
whole thing.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Acked-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>