[tip:perf/core] tracing: Don't print an extra separator of flags

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Commit-ID:  e404b321dbb2d6e438522b7dce9c1d0c6a8c5275
Gitweb:     http://git.kernel.org/tip/e404b321dbb2d6e438522b7dce9c1d0c6a8c5275
Author:     Andrey Vagin <avagin@xxxxxxxxxx>
AuthorDate: Sun, 19 Feb 2012 14:16:07 +0300
Committer:  Steven Rostedt <rostedt@xxxxxxxxxxx>
CommitDate: Mon, 20 Feb 2012 20:33:31 -0500

tracing: Don't print an extra separator of flags

If __print_flags() is used after another __print_*() function, the
temp seq_file buffer will not be empty on entry, and the delimiter will
be printed even though there's just one field. We get something like:

	|S

instead of just:

	S

This is because the length of the temp seq buffer is used to determine
if the delimiter is printed or not. But this algorithm fails when
the seq buffer is not empty on entry, and the delimiter will be printed
because it thinks that a previous field was already printed.

Link: http://lkml.kernel.org/r/1329650167-480655-1-git-send-email-avagin@xxxxxxxxxx

Signed-off-by: Andrew Vagin <avagin@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
---
 kernel/trace/trace_output.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 0d6ff355..3efd718 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -300,7 +300,7 @@ ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
 	unsigned long mask;
 	const char *str;
 	const char *ret = p->buffer + p->len;
-	int i;
+	int i, first = 1;
 
 	for (i = 0;  flag_array[i].name && flags; i++) {
 
@@ -310,8 +310,10 @@ ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
 
 		str = flag_array[i].name;
 		flags &= ~mask;
-		if (p->len && delim)
+		if (!first && delim)
 			trace_seq_puts(p, delim);
+		else
+			first = 0;
 		trace_seq_puts(p, str);
 	}
 
--
To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux Stable Commits]     [Linux Stable Kernel]     [Linux Kernel]     [Linux USB Devel]     [Linux Video &Media]     [Linux Audio Users]     [Yosemite News]     [Linux SCSI]

  Powered by Linux