From: Steven Rostedt <srostedt@redhat.com>
Date: Tue, 7 Jun 2011 02:35:13 +0000 (-0400)
Subject: kprobes/trace: Fix kprobe selftest for gcc 4.6
X-Git-Tag: v3.0-rc3~4^2~1^2~1
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=265a5b7ee3eb21a4d0e53e17d59ba6eada91af39;p=profile%2Fivi%2Fkernel-x86-ivi.git

kprobes/trace: Fix kprobe selftest for gcc 4.6

With gcc 4.6, the self test kprobe function:

 kprobe_trace_selftest_target()

is optimized such that kallsyms does not list it. The kprobes
test uses this function to insert a probe and test it. But
it will fail the test if the function is not listed in kallsyms.

Adding a __used annotation keeps the symbol in the kallsyms table.

Suggested-by: David Daney <ddaney@caviumnetworks.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---

diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index f925c45..27d13b3 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1870,8 +1870,12 @@ fs_initcall(init_kprobe_trace);
 
 #ifdef CONFIG_FTRACE_STARTUP_TEST
 
-static int kprobe_trace_selftest_target(int a1, int a2, int a3,
-					int a4, int a5, int a6)
+/*
+ * The "__used" keeps gcc from removing the function symbol
+ * from the kallsyms table.
+ */
+static __used int kprobe_trace_selftest_target(int a1, int a2, int a3,
+					       int a4, int a5, int a6)
 {
 	return a1 + a2 + a3 + a4 + a5 + a6;
 }