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

View file

@ -147,6 +147,7 @@ struct request {
unsigned int cmd_flags;
enum rq_cmd_type_bits cmd_type;
unsigned long atomic_flags;
/* Maintain bio traversal state for part by part I/O submission.
* hard_* are block layer internals, no driver should touch them!
@ -214,6 +215,8 @@ struct request {
void *data;
void *sense;
unsigned long deadline;
struct list_head timeout_list;
unsigned int timeout;
int retries;
@ -266,6 +269,14 @@ typedef void (prepare_flush_fn) (struct request_queue *, struct request *);
typedef void (softirq_done_fn)(struct request *);
typedef int (dma_drain_needed_fn)(struct request *);
enum blk_eh_timer_return {
BLK_EH_NOT_HANDLED,
BLK_EH_HANDLED,
BLK_EH_RESET_TIMER,
};
typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
enum blk_queue_state {
Queue_down,
Queue_up,
@ -311,6 +322,7 @@ struct request_queue
merge_bvec_fn *merge_bvec_fn;
prepare_flush_fn *prepare_flush_fn;
softirq_done_fn *softirq_done_fn;
rq_timed_out_fn *rq_timed_out_fn;
dma_drain_needed_fn *dma_drain_needed;
/*
@ -386,6 +398,10 @@ struct request_queue
unsigned int nr_sorted;
unsigned int in_flight;
unsigned int rq_timeout;
struct timer_list timeout;
struct list_head timeout_list;
/*
* sg stuff
*/
@ -770,6 +786,8 @@ extern int blk_end_request_callback(struct request *rq, int error,
unsigned int nr_bytes,
int (drv_callback)(struct request *));
extern void blk_complete_request(struct request *);
extern void __blk_complete_request(struct request *);
extern void blk_abort_request(struct request *);
/*
* blk_end_request() takes bytes instead of sectors as a complete size.
@ -811,6 +829,8 @@ extern void blk_queue_dma_alignment(struct request_queue *, int);
extern void blk_queue_update_dma_alignment(struct request_queue *, int);
extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
extern void blk_queue_set_discard(struct request_queue *, prepare_discard_fn *);
extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
extern int blk_queue_ordered(struct request_queue *, unsigned, prepare_flush_fn *);
extern int blk_do_ordered(struct request_queue *, struct request **);