From: Johannes Berg <johannes@sipsolutions.net>
Date: Fri, 13 Nov 2009 22:40:09 +0000 (+0100)
Subject: tracing: Fix event format export
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=811cb50baf63461ce0bdb234927046131fc7fa8b;p=deliverable%2Flinux.git

tracing: Fix event format export

For some reason the export of the event print format to userspace
uses '#fmt' which breaks if the format string is anything but a plain
string, for example if it is built with macros then the macro names
are exported instead of their contents.

Use
	"\"%s\"", fmt
instead of
	"%s", #fmt
to export the string and not the way it is built.

For example, in net/mac80211/driver-trace.h for the trace event drv_start
there is:

        TP_printk(
                LOCAL_PR_FMT, LOCAL_PR_ARG
        )

Which use to produce:

 print fmt: LOCAL_PR_FMT, REC->wiphy_name

Now produces:

 print fmt: "%s", REC->wiphy_name

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
LKML-Reference: <20091113224009.GB23942@elte.hu>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---

diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index cc0d9667e182..dacb8ef67000 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -159,7 +159,7 @@
 #undef __get_str
 
 #undef TP_printk
-#define TP_printk(fmt, args...) "%s, %s\n", #fmt, __stringify(args)
+#define TP_printk(fmt, args...) "\"%s\", %s\n", fmt, __stringify(args)
 
 #undef TP_fast_assign
 #define TP_fast_assign(args...) args