diff options
author | Tejun Heo <tj@kernel.org> | 2011-12-14 00:33:40 +0100 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2011-12-14 00:33:40 +0100 |
commit | f2dbd76a0a994bc1d5a3d0e7c844cc373832e86c (patch) | |
tree | cae6a4333ee6e5eb76ef133dfdee95e1943c0ab1 /block/cfq-iosched.c | |
parent | 1238033c79e92e5c315af12e45396f1a78c73dec (diff) | |
download | lwn-f2dbd76a0a994bc1d5a3d0e7c844cc373832e86c.tar.gz lwn-f2dbd76a0a994bc1d5a3d0e7c844cc373832e86c.zip |
block, cfq: replace current_io_context() with create_io_context()
When called under queue_lock, current_io_context() triggers lockdep
warning if it hits allocation path. This is because io_context
installation is protected by task_lock which is not IRQ safe, so it
triggers irq-unsafe-lock -> irq -> irq-safe-lock -> irq-unsafe-lock
deadlock warning.
Given the restriction, accessor + creator rolled into one doesn't work
too well. Drop current_io_context() and let the users access
task->io_context directly inside queue_lock combined with explicit
creation using create_io_context().
Future ioc updates will further consolidate ioc access and the create
interface will be unexported.
While at it, relocate ioc internal interface declarations in blk.h and
add section comments before and after.
This patch does not introduce functional change.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/cfq-iosched.c')
-rw-r--r-- | block/cfq-iosched.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 3b07ce168780..5f7e4d161404 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -3012,7 +3012,7 @@ static int cfq_create_cic(struct cfq_data *cfqd, gfp_t gfp_mask) might_sleep_if(gfp_mask & __GFP_WAIT); /* allocate stuff */ - ioc = current_io_context(gfp_mask, q->node); + ioc = create_io_context(current, gfp_mask, q->node); if (!ioc) goto out; |