block: remove per-queue plugging

[deliverable/linux.git] / include / linux / blkdev.h

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index f55b2a8b66104997446cd1557e86527e337d6398..64ab2a1bb1679b1583f00a44a2b1af0ec9e3f168 100644 (file)
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -196,7 +196,6 @@ typedef void (request_fn_proc) (struct request_queue *q);
 typedef int (make_request_fn) (struct request_queue *q, struct bio *bio);
 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
 typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
-typedef void (unplug_fn) (struct request_queue *);
 
 struct bio_vec;
 struct bvec_merge_data {
@@ -279,7 +278,6 @@ struct request_queue
        make_request_fn         *make_request_fn;
        prep_rq_fn              *prep_rq_fn;
        unprep_rq_fn            *unprep_rq_fn;
-       unplug_fn               *unplug_fn;
        merge_bvec_fn           *merge_bvec_fn;
        softirq_done_fn         *softirq_done_fn;
        rq_timed_out_fn         *rq_timed_out_fn;
@@ -292,14 +290,6 @@ struct request_queue
        sector_t                end_sector;
        struct request          *boundary_rq;
 
-       /*
-        * Auto-unplugging state
-        */
-       struct timer_list       unplug_timer;
-       int                     unplug_thresh;  /* After this many requests */
-       unsigned long           unplug_delay;   /* After this many jiffies */
-       struct work_struct      unplug_work;
-
        /*
         * Delayed queue handling
         */
@@ -399,14 +389,13 @@ struct request_queue
 #define QUEUE_FLAG_ASYNCFULL   4       /* write queue has been filled */
 #define QUEUE_FLAG_DEAD                5       /* queue being torn down */
 #define QUEUE_FLAG_REENTER     6       /* Re-entrancy avoidance */
-#define QUEUE_FLAG_PLUGGED     7       /* queue is plugged */
-#define QUEUE_FLAG_ELVSWITCH   8       /* don't use elevator, just do FIFO */
-#define QUEUE_FLAG_BIDI                9       /* queue supports bidi requests */
-#define QUEUE_FLAG_NOMERGES    10      /* disable merge attempts */
-#define QUEUE_FLAG_SAME_COMP   11      /* force complete on same CPU */
-#define QUEUE_FLAG_FAIL_IO     12      /* fake timeout */
-#define QUEUE_FLAG_STACKABLE   13      /* supports request stacking */
-#define QUEUE_FLAG_NONROT      14      /* non-rotational device (SSD) */
+#define QUEUE_FLAG_ELVSWITCH   7       /* don't use elevator, just do FIFO */
+#define QUEUE_FLAG_BIDI                8       /* queue supports bidi requests */
+#define QUEUE_FLAG_NOMERGES     9      /* disable merge attempts */
+#define QUEUE_FLAG_SAME_COMP   10      /* force complete on same CPU */
+#define QUEUE_FLAG_FAIL_IO     11      /* fake timeout */
+#define QUEUE_FLAG_STACKABLE   12      /* supports request stacking */
+#define QUEUE_FLAG_NONROT      13      /* non-rotational device (SSD) */
 #define QUEUE_FLAG_VIRT        QUEUE_FLAG_NONROT /* paravirt device */
 #define QUEUE_FLAG_IO_STAT     15      /* do IO stats */
 #define QUEUE_FLAG_DISCARD     16      /* supports DISCARD */
@@ -484,7 +473,6 @@ static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
        __clear_bit(flag, &q->queue_flags);
 }
 
-#define blk_queue_plugged(q)   test_bit(QUEUE_FLAG_PLUGGED, &(q)->queue_flags)
 #define blk_queue_tagged(q)    test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
 #define blk_queue_stopped(q)   test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
 #define blk_queue_nomerges(q)  test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
@@ -679,9 +667,6 @@ extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
 extern void blk_rq_unprep_clone(struct request *rq);
 extern int blk_insert_cloned_request(struct request_queue *q,
                                     struct request *rq);
-extern void blk_plug_device(struct request_queue *);
-extern void blk_plug_device_unlocked(struct request_queue *);
-extern int blk_remove_plug(struct request_queue *);
 extern void blk_delay_queue(struct request_queue *, unsigned long);
 extern void blk_recount_segments(struct request_queue *, struct bio *);
 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
@@ -726,7 +711,6 @@ extern int blk_execute_rq(struct request_queue *, struct gendisk *,
                          struct request *, int);
 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
                                  struct request *, int, rq_end_io_fn *);
-extern void blk_unplug(struct request_queue *q);
 
 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
 {
@@ -863,7 +847,6 @@ extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bd
 
 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
 extern void blk_dump_rq_flags(struct request *, char *);
-extern void generic_unplug_device(struct request_queue *);
 extern long nr_blockdev_pages(void);
 
 int blk_get_queue(struct request_queue *);
@@ -871,6 +854,31 @@ struct request_queue *blk_alloc_queue(gfp_t);
 struct request_queue *blk_alloc_queue_node(gfp_t, int);
 extern void blk_put_queue(struct request_queue *);
 
+struct blk_plug {
+       unsigned long magic;
+       struct list_head list;
+       unsigned int should_sort;
+};
+
+extern void blk_start_plug(struct blk_plug *);
+extern void blk_finish_plug(struct blk_plug *);
+extern void __blk_flush_plug(struct task_struct *, struct blk_plug *);
+
+static inline void blk_flush_plug(struct task_struct *tsk)
+{
+       struct blk_plug *plug = tsk->plug;
+
+       if (unlikely(plug))
+               __blk_flush_plug(tsk, plug);
+}
+
+static inline bool blk_needs_flush_plug(struct task_struct *tsk)
+{
+       struct blk_plug *plug = tsk->plug;
+
+       return plug && !list_empty(&plug->list);
+}
+
 /*
  * tag stuff
  */
@@ -1294,6 +1302,23 @@ static inline long nr_blockdev_pages(void)
        return 0;
 }
 
+static inline void blk_start_plug(struct list_head *list)
+{
+}
+
+static inline void blk_finish_plug(struct list_head *list)
+{
+}
+
+static inline void blk_flush_plug(struct task_struct *tsk)
+{
+}
+
+static inline bool blk_needs_flush_plug(struct task_struct *tsk)
+{
+       return false;
+}
+
 #endif /* CONFIG_BLOCK */
 
 #endif