blktrace: add FLUSH/FUA support

Add FLUSH/FUA support to blktrace. As FLUSH precedes WRITE and/or
FUA follows WRITE, use the same 'F' flag for both cases and
distinguish them by their (relative) position. The end results
look like (other flags might be shown also):

 - WRITE:            W
 - WRITE_FLUSH:      FW
 - WRITE_FUA:        WF
 - WRITE_FLUSH_FUA:  FWF

Note that we reuse TC_BARRIER due to lack of bit space of act_mask
so that the older versions of blktrace tools will report flush
requests as barriers from now on.

Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

2 files changed, 14 insertions, 11 deletions

diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h
index 8c7c2de7631a..8e9e4bc6d73b 100644
--- a/include/linux/blktrace_api.h
+++ b/include/linux/blktrace_api.h
@@ -14,7 +14,7 @@
 enum blktrace_cat {
         BLK_TC_READ     = 1 << 0,       /* reads */
         BLK_TC_WRITE    = 1 << 1,       /* writes */
-        BLK_TC_BARRIER  = 1 << 2,       /* barrier */
+        BLK_TC_FLUSH    = 1 << 2,       /* flush */
         BLK_TC_SYNC     = 1 << 3,       /* sync IO */
         BLK_TC_SYNCIO   = BLK_TC_SYNC,
         BLK_TC_QUEUE    = 1 << 4,       /* queueing/merging */
@@ -28,8 +28,9 @@ enum blktrace_cat {
         BLK_TC_META     = 1 << 12,      /* metadata */
         BLK_TC_DISCARD  = 1 << 13,      /* discard requests */
         BLK_TC_DRV_DATA = 1 << 14,      /* binary per-driver data */
+        BLK_TC_FUA      = 1 << 15,      /* fua requests */
 
-        BLK_TC_END      = 1 << 15,      /* only 16-bits, reminder */
+        BLK_TC_END      = 1 << 15,      /* we've run out of bits! */
 };
 
 #define BLK_TC_SHIFT            (16)
diff --git a/include/trace/events/block.h b/include/trace/events/block.h
index bf366547da25..05c5e61f0a7c 100644
--- a/include/trace/events/block.h
+++ b/include/trace/events/block.h
@@ -8,6 +8,8 @@
 #include <linux/blkdev.h>
 #include <linux/tracepoint.h>
 
+#define RWBS_LEN        8
+
 DECLARE_EVENT_CLASS(block_rq_with_error,
 
         TP_PROTO(struct request_queue *q, struct request *rq),
@@ -19,7 +21,7 @@ DECLARE_EVENT_CLASS(block_rq_with_error,
                 __field(  sector_t,     sector                  )
                 __field(  unsigned int, nr_sector               )
                 __field(  int,          errors                  )
-                __array(  char,         rwbs,   6               )
+                __array(  char,         rwbs,   RWBS_LEN        )
                 __dynamic_array( char,  cmd,    blk_cmd_buf_len(rq)     )
         ),
 
@@ -104,7 +106,7 @@ DECLARE_EVENT_CLASS(block_rq,
                 __field(  sector_t,     sector                  )
                 __field(  unsigned int, nr_sector               )
                 __field(  unsigned int, bytes                   )
-                __array(  char,         rwbs,   6               )
+                __array(  char,         rwbs,   RWBS_LEN        )
                 __array(  char,         comm,   TASK_COMM_LEN   )
                 __dynamic_array( char,  cmd,    blk_cmd_buf_len(rq)     )
         ),
@@ -183,7 +185,7 @@ TRACE_EVENT(block_bio_bounce,
                 __field( dev_t,         dev                     )
                 __field( sector_t,      sector                  )
                 __field( unsigned int,  nr_sector               )
-                __array( char,          rwbs,   6               )
+                __array( char,          rwbs,   RWBS_LEN        )
                 __array( char,          comm,   TASK_COMM_LEN   )
         ),
 
@@ -222,7 +224,7 @@ TRACE_EVENT(block_bio_complete,
                 __field( sector_t,      sector          )
                 __field( unsigned,      nr_sector       )
                 __field( int,           error           )
-                __array( char,          rwbs,   6       )
+                __array( char,          rwbs,   RWBS_LEN)
         ),
 
         TP_fast_assign(
@@ -249,7 +251,7 @@ DECLARE_EVENT_CLASS(block_bio,
                 __field( dev_t,         dev                     )
                 __field( sector_t,      sector                  )
                 __field( unsigned int,  nr_sector               )
-                __array( char,          rwbs,   6               )
+                __array( char,          rwbs,   RWBS_LEN        )
                 __array( char,          comm,   TASK_COMM_LEN   )
         ),
 
@@ -321,7 +323,7 @@ DECLARE_EVENT_CLASS(block_get_rq,
                 __field( dev_t,         dev                     )
                 __field( sector_t,      sector                  )
                 __field( unsigned int,  nr_sector               )
-                __array( char,          rwbs,   6               )
+                __array( char,          rwbs,   RWBS_LEN        )
                 __array( char,          comm,   TASK_COMM_LEN   )
         ),
 
@@ -456,7 +458,7 @@ TRACE_EVENT(block_split,
                 __field( dev_t,         dev                             )
                 __field( sector_t,      sector                          )
                 __field( sector_t,      new_sector                      )
-                __array( char,          rwbs,           6               )
+                __array( char,          rwbs,           RWBS_LEN        )
                 __array( char,          comm,           TASK_COMM_LEN   )
         ),
 
@@ -498,7 +500,7 @@ TRACE_EVENT(block_bio_remap,
                 __field( unsigned int,  nr_sector       )
                 __field( dev_t,         old_dev         )
                 __field( sector_t,      old_sector      )
-                __array( char,          rwbs,   6       )
+                __array( char,          rwbs,   RWBS_LEN)
         ),
 
         TP_fast_assign(
@@ -542,7 +544,7 @@ TRACE_EVENT(block_rq_remap,
                 __field( unsigned int,  nr_sector       )
                 __field( dev_t,         old_dev         )
                 __field( sector_t,      old_sector      )
-                __array( char,          rwbs,   6       )
+                __array( char,          rwbs,   RWBS_LEN)
         ),
 
         TP_fast_assign(