ftrace: support for PowerPC

This patch adds full support for ftrace for PowerPC (both 64 and 32 bit).
This includes dynamic tracing and function filtering.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 9 insertions, 2 deletions

diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index a5f6001c3332..3877dd9102f1 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -123,6 +123,7 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
         int ret;
         int save_ftrace_enabled = ftrace_enabled;
         int save_tracer_enabled = tracer_enabled;
+        char *func_name;
 
         /* The ftrace test PASSED */
         printk(KERN_CONT "PASSED\n");
@@ -142,9 +143,15 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
                 return ret;
         }
 
+        /*
+         * Some archs *cough*PowerPC*cough* add charachters to the
+         * start of the function names. We simply put a '*' to
+         * accomodate them.
+         */
+        func_name = "*" STR(DYN_FTRACE_TEST_NAME);
+
         /* filter only on our function */
-        ftrace_set_filter(STR(DYN_FTRACE_TEST_NAME),
-                          sizeof(STR(DYN_FTRACE_TEST_NAME)), 1);
+        ftrace_set_filter(func_name, strlen(func_name), 1);
 
         /* enable tracing */
         tr->ctrl = 1;