powerpc/ftrace: simplify prepare_ftrace_return
authorAnton Blanchard <anton@samba.org>
Wed, 17 Sep 2014 07:07:04 +0000 (17:07 +1000)
committerMichael Ellerman <mpe@ellerman.id.au>
Sun, 9 Nov 2014 22:59:28 +0000 (09:59 +1100)
commitb3c18725a0eb7ea2458e9ae3b7e5a477f52e361f
treefaecb26b2ba42de9abe84471f02d8230f81a2b06
parent7d56c65a6ff9065c459fc63c509950d8ea66e00c
powerpc/ftrace: simplify prepare_ftrace_return

Instead of passing in the stack address of the link register
to be modified, just pass in the old value and return the
new value and rely on ftrace_graph_caller to do the
modification.

This removes the exception handling around the stack update -
it isn't needed and we weren't consistent about it. Later on
we would do an unprotected modification:

       if (!ftrace_graph_entry(&trace)) {
               *parent = old;

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch/powerpc/kernel/entry_32.S
arch/powerpc/kernel/entry_64.S
arch/powerpc/kernel/ftrace.c