[BLOCK] ll_rw_blk: Enable out-of-order request completions through softirq
Request completion can be a quite heavy process, since it needs to
iterate through the entire request and complete the bio's it holds.
This patch adds blk_complete_request() which moves this processing
into a dedicated block softirq.
Signed-off-by: Jens Axboe <axboe@suse.de>
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index fb09853..804cc4e 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -118,9 +118,9 @@
* try to put the fields that are referenced together in the same cacheline
*/
struct request {
- struct list_head queuelist; /* looking for ->queue? you must _not_
- * access it directly, use
- * blkdev_dequeue_request! */
+ struct list_head queuelist;
+ struct list_head donelist;
+
unsigned long flags; /* see REQ_ bits below */
/* Maintain bio traversal state for part by part I/O submission.
@@ -141,6 +141,7 @@
struct bio *biotail;
void *elevator_private;
+ void *completion_data;
unsigned short ioprio;
@@ -291,6 +292,7 @@
typedef void (activity_fn) (void *data, int rw);
typedef int (issue_flush_fn) (request_queue_t *, struct gendisk *, sector_t *);
typedef void (prepare_flush_fn) (request_queue_t *, struct request *);
+typedef void (softirq_done_fn)(struct request *);
enum blk_queue_state {
Queue_down,
@@ -332,6 +334,7 @@
activity_fn *activity_fn;
issue_flush_fn *issue_flush_fn;
prepare_flush_fn *prepare_flush_fn;
+ softirq_done_fn *softirq_done_fn;
/*
* Dispatch queue sorting
@@ -646,6 +649,17 @@
extern int end_that_request_chunk(struct request *, int, int);
extern void end_that_request_last(struct request *, int);
extern void end_request(struct request *req, int uptodate);
+extern void blk_complete_request(struct request *);
+
+static inline int rq_all_done(struct request *rq, unsigned int nr_bytes)
+{
+ if (blk_fs_request(rq))
+ return (nr_bytes >= (rq->hard_nr_sectors << 9));
+ else if (blk_pc_request(rq))
+ return nr_bytes >= rq->data_len;
+
+ return 0;
+}
/*
* end_that_request_first/chunk() takes an uptodate argument. we account
@@ -694,6 +708,7 @@
extern void blk_queue_prep_rq(request_queue_t *, prep_rq_fn *pfn);
extern void blk_queue_merge_bvec(request_queue_t *, merge_bvec_fn *);
extern void blk_queue_dma_alignment(request_queue_t *, int);
+extern void blk_queue_softirq_done(request_queue_t *, softirq_done_fn *);
extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
extern int blk_queue_ordered(request_queue_t *, unsigned, prepare_flush_fn *);
extern void blk_queue_issue_flush_fn(request_queue_t *, issue_flush_fn *);
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index e50a95f..f022047 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -112,6 +112,7 @@
TIMER_SOFTIRQ,
NET_TX_SOFTIRQ,
NET_RX_SOFTIRQ,
+ BLOCK_SOFTIRQ,
SCSI_SOFTIRQ,
TASKLET_SOFTIRQ
};