[PATCH] Remove struct request_list from struct request

It is always identical to &q->rq, and we only use it for detecting
whether this request came out of our mempool or not. So replace it
with an additional ->flags bit flag.

Signed-off-by: Jens Axboe <axboe@suse.de>

2 files changed, 4 insertions, 9 deletions

diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
index 3b6aad2affd8..f7462502bfdf 100644
--- a/block/ll_rw_blk.c
+++ b/block/ll_rw_blk.c
@@ -452,7 +452,6 @@ static void queue_flush(request_queue_t *q, unsigned which)
         rq->elevator_private = NULL;
         rq->elevator_private2 = NULL;
         rq->rq_disk = q->bar_rq.rq_disk;
-        rq->rl = NULL;
         rq->end_io = end_io;
         q->prepare_flush_fn(q, rq);
 
@@ -480,7 +479,6 @@ static inline struct request *start_ordered(request_queue_t *q,
         rq->cmd_flags |= q->ordered & QUEUE_ORDERED_FUA ? REQ_FUA : 0;
         rq->elevator_private = NULL;
         rq->elevator_private2 = NULL;
-        rq->rl = NULL;
         init_request_from_bio(rq, q->orig_bar_rq->bio);
         rq->end_io = bar_end_io;
 
@@ -2018,7 +2016,7 @@ blk_alloc_request(request_queue_t *q, int rw, struct bio *bio,
          * first three bits are identical in rq->cmd_flags and bio->bi_rw,
          * see bio.h and blkdev.h
          */
-        rq->cmd_flags = rw;
+        rq->cmd_flags = rw | REQ_ALLOCED;
 
         if (priv) {
                 if (unlikely(elv_set_request(q, rq, bio, gfp_mask))) {
@@ -2196,7 +2194,6 @@ rq_starved:
                 ioc->nr_batch_requests--;
         
         rq_init(q, rq);
-        rq->rl = rl;
 
         blk_add_trace_generic(q, bio, rw, BLK_TA_GETRQ);
 out:
@@ -2681,8 +2678,6 @@ EXPORT_SYMBOL_GPL(disk_round_stats);
  */
 void __blk_put_request(request_queue_t *q, struct request *req)
 {
-        struct request_list *rl = req->rl;
-
         if (unlikely(!q))
                 return;
         if (unlikely(--req->ref_count))
@@ -2691,13 +2686,12 @@ void __blk_put_request(request_queue_t *q, struct request *req)
         elv_completed_request(q, req);
 
         req->rq_status = RQ_INACTIVE;
-        req->rl = NULL;
 
         /*
          * Request may not have originated from ll_rw_blk. if not,
          * it didn't come out of our reserved rq pools
          */
-        if (rl) {
+        if (req->cmd_flags & REQ_ALLOCED) {
                 int rw = rq_data_dir(req);
                 int priv = req->cmd_flags & REQ_ELVPRIV;
 
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 604f23189097..d4c1dd046e27 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -180,6 +180,7 @@ enum rq_flag_bits {
         __REQ_PREEMPT,          /* set for "ide_preempt" requests */
         __REQ_ORDERED_COLOR,    /* is before or after barrier */
         __REQ_RW_SYNC,          /* request is sync (O_DIRECT) */
+        __REQ_ALLOCED,          /* request came from our alloc pool */
         __REQ_NR_BITS,          /* stops here */
 };
 
@@ -199,6 +200,7 @@ enum rq_flag_bits {
 #define REQ_PREEMPT     (1 << __REQ_PREEMPT)
 #define REQ_ORDERED_COLOR       (1 << __REQ_ORDERED_COLOR)
 #define REQ_RW_SYNC     (1 << __REQ_RW_SYNC)
+#define REQ_ALLOCED     (1 << __REQ_ALLOCED)
 
 #define BLK_MAX_CDB     16
 
@@ -264,7 +266,6 @@ struct request {
 
         int ref_count;
         request_queue_t *q;
-        struct request_list *rl;
 
         void *special;
         char *buffer;