[tip:tracing/blktrace] blktrace: fix wrong calculation of RWBS

Li Zefan
2009-03-24T12:13:59Z

Commit-ID: 65796348e09880e12b97267d39b8857c758440a6
Gitweb: http://git.kernel.org/tip/65796348e09880e12b97267d39b8857c758440a6
Author: Li Zefan <lizf@cn.fujitsu.com>
AuthorDate: Tue, 24 Mar 2009 16:05:06 +0800
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Tue, 24 Mar 2009 13:08:59 +0100

blktrace: fix wrong calculation of RWBS

Impact: fix the output of IO type category characters

Trace categories are the upper 16 bits, not the lower 16 bits.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <49C89432.8010805@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

---
kernel/trace/blktrace.c | 13 +++++++------
1 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 1ffcbd4..9af4143 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -922,23 +922,24 @@ static void blk_unregister_tracepoints(void)
static void fill_rwbs(char *rwbs, const struct blk_io_trace *t)
{
int i = 0;
+ int tc = t->action >> BLK_TC_SHIFT;

- if (t->action & BLK_TC_DISCARD)
+ if (tc & BLK_TC_DISCARD)
rwbs[i++] = 'D';
- else if (t->action & BLK_TC_WRITE)
+ else if (tc & BLK_TC_WRITE)
rwbs[i++] = 'W';
else if (t->bytes)
rwbs[i++] = 'R';
else
rwbs[i++] = 'N';

- if (t->action & BLK_TC_AHEAD)
+ if (tc & BLK_TC_AHEAD)
rwbs[i++] = 'A';
- if (t->action & BLK_TC_BARRIER)
+ if (tc & BLK_TC_BARRIER)
rwbs[i++] = 'B';
- if (t->action & BLK_TC_SYNC)
+ if (tc & BLK_TC_SYNC)
rwbs[i++] = 'S';
- if (t->action & BLK_TC_META)
+ if (tc & BLK_TC_META)
rwbs[i++] = 'M';

rwbs[i] = '\0';