[PATCH] Block queue IO tracing support (blktrace) as of 2006-03-23

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

1 files changed, 12 insertions, 1 deletions

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 26b08ee425c7..8c82373f7ff3 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -17,6 +17,7 @@
 #include <linux/mempool.h>
 #include <linux/slab.h>
 #include <linux/idr.h>
+#include <linux/blktrace_api.h>
 
 static const char *_name = DM_NAME;
 
@@ -334,6 +335,8 @@ static void dec_pending(struct dm_io *io, int error)
                         /* nudge anyone waiting on suspend queue */
                         wake_up(&io->md->wait);
 
+                blk_add_trace_bio(io->md->queue, io->bio, BLK_TA_COMPLETE);
+
                 bio_endio(io->bio, io->bio->bi_size, io->error);
                 free_io(io->md, io);
         }
@@ -392,6 +395,7 @@ static void __map_bio(struct dm_target *ti, struct bio *clone,
                       struct target_io *tio)
 {
         int r;
+        sector_t sector;
 
         /*
          * Sanity checks.
@@ -407,10 +411,17 @@ static void __map_bio(struct dm_target *ti, struct bio *clone,
          * this io.
          */
         atomic_inc(&tio->io->io_count);
+        sector = clone->bi_sector;
         r = ti->type->map(ti, clone, &tio->info);
-        if (r > 0)
+        if (r > 0) {
                 /* the bio has been remapped so dispatch it */
+
+                blk_add_trace_remap(bdev_get_queue(clone->bi_bdev), clone, 
+                                    tio->io->bio->bi_bdev->bd_dev, sector, 
+                                    clone->bi_sector);
+
                 generic_make_request(clone);
+        }
 
         else if (r < 0) {
                 /* error the io and bail out */