On Thu, Mar 13, 2014 at 06:27:39PM +0000, Steven Rostedt wrote: > On Thu, 2014-03-13 at 17:08 +0000, Will Deacon wrote: > > > > + /* > > > + * Note: > > > + * No protection against faulting at *parent, which may be seen > > > + * on other archs. It's unlikely on AArch64. > > > + */ > > > + old = *parent; > > > + *parent = return_hooker; > > > > return_hook? People might take it personally otherwise ;) > > No, return_hooker is consistent with all the other archs. Hey, it's a > rugby position! Note, which I was when I played. ;-)
Hehe, in which case your children will be able to execute that line of ftrace! > > > > > + trace.func = self_addr; > > > > in kernel/ftrace/ftrace.c there's an smb_wmb() between setting up > > tracing_graph_pause and setting the ret_stack with a comment saying: > > > > /* Make sure the tasks see the -1 first: */ > > > > Why don't we have a corresponding read-barrier here? > > The corresponding rmb is in kernel/trace/trace_function_graph > ftrace_push_return_trace(). Okey doke then, I guess we don't really care about tracing_graph_pause getting out-of-sync with curr_ret_stack. Will -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
