From: Steven Rostedt (Red Hat) Date: Wed, 25 Jun 2014 13:53:21 +0000 (-0400) Subject: MIPS: ftrace: Add call to ftrace_graph_is_dead() in function graph code X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=6a8a5051130fd2e2b5f978a5a2e222fcc7d2dff4;p=deliverable%2Flinux.git MIPS: ftrace: Add call to ftrace_graph_is_dead() in function graph code ftrace_stop() is going away as it disables parts of function tracing that affects users that should not be affected. But ftrace_graph_stop() is built on ftrace_stop(). Here's another example of killing all of function tracing because something went wrong with function graph tracing. Instead of disabling all users of function tracing on function graph error, disable only function graph tracing. To do this, the arch code must call ftrace_graph_is_dead() before it implements function graph. Cc: Ralf Baechle Tested-by: James Hogan Signed-off-by: Steven Rostedt --- diff --git a/arch/mips/kernel/ftrace.c b/arch/mips/kernel/ftrace.c index 60e7e5e45af1..8b6538750fe1 100644 --- a/arch/mips/kernel/ftrace.c +++ b/arch/mips/kernel/ftrace.c @@ -302,6 +302,9 @@ void prepare_ftrace_return(unsigned long *parent_ra_addr, unsigned long self_ra, &return_to_handler; int faulted, insns; + if (unlikely(ftrace_graph_is_dead())) + return; + if (unlikely(atomic_read(¤t->tracing_graph_pause))) return;