From mboxrd@z Thu Jan 1 00:00:00 1970 From: rostedt@goodmis.org (Steven Rostedt) Date: Fri, 18 Jul 2014 17:22:21 -0400 Subject: [PATCH 2/4] ARM: add IPI tracepoints In-Reply-To: References: <1405660735-13408-1-git-send-email-nicolas.pitre@linaro.org> <1405660735-13408-3-git-send-email-nicolas.pitre@linaro.org> <20140718160418.54d11f6a@gandalf.local.home> Message-ID: <20140718172221.6dbe83e4@gandalf.local.home> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, 18 Jul 2014 16:55:42 -0400 (EDT) Nicolas Pitre wrote: > > Here's the patch I have at the head of the series now, with the above > ugliness changed to an unconditional __tracepoint_string attribute. > I was thinking of something like this. Feel free to add this to your series. -- Steve From: Steven Rostedt Subject: [PATCH] tracing: Do not do anything special with tracepoint_string when tracing is disabled When CONFIG_TRACING is not enabled, there's no reason to save the trace strings either by the linker or as a static variable that can be referenced later. Simply pass back the string that is given to tracepoint_string(). Signed-off-by: Steven Rostedt --- diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index cff3106..b296363 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -574,6 +574,7 @@ do { \ __trace_printk(ip, fmt, ##args); \ } while (0) +#ifdef CONFIG_TRACING /** * tracepoint_string - register constant persistent string to trace system * @str - a constant persistent string that will be referenced in tracepoints @@ -607,6 +608,15 @@ do { \ ___tp_str; \ }) #define __tracepoint_string __attribute__((section("__tracepoint_str"))) +#else +/* + * tracepoint_string() is used to save the string address for userspace + * tracing tools. When tracing isn't configured, there's no need to save + * anything. + */ +# define tracepoint_string(str) str +# define __tracepoint_string +#endif #ifdef CONFIG_PERF_EVENTS struct perf_event;