block: unify request timeout handling

Right now SCSI and others do their own command timeout handling.
Move those bits to the block layer.

Instead of having a timer per command, we try to be a bit more clever
and simply have one per-queue. This avoids the overhead of having to
tear down and setup a timer for each command, so it will result in a lot
less timer fiddling.

Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
Jens Axboe
2008-09-14 05:55:09 -07:00
parent 608aeef17a
commit 242f9dcb8b
39 changed files with 399 additions and 339 deletions
+24
View File
@@ -17,6 +17,30 @@ void __blk_queue_free_tags(struct request_queue *q);
void blk_unplug_work(struct work_struct *work);
void blk_unplug_timeout(unsigned long data);
void blk_rq_timed_out_timer(unsigned long data);
void blk_delete_timer(struct request *);
void blk_add_timer(struct request *);
/*
* Internal atomic flags for request handling
*/
enum rq_atomic_flags {
REQ_ATOM_COMPLETE = 0,
};
/*
* EH timer and IO completion will both attempt to 'grab' the request, make
* sure that only one of them suceeds
*/
static inline int blk_mark_rq_complete(struct request *rq)
{
return test_and_set_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags);
}
static inline void blk_clear_rq_complete(struct request *rq)
{
clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags);
}
struct io_context *current_io_context(gfp_t gfp_flags, int node);