Commit 700e6437 authored Apr 19, 2017 by Naveen N. Rao Committed by Michael Ellerman Apr 23, 2017

powerpc/ftrace: Move stack setup and teardown code into ftrace_graph_caller()



Move the stack setup and teardown code into ftrace_graph_caller(). This way, we
don't incur the cost of setting it up unless function graph is enabled for this
function.

Also, remove the extraneous LR restore code after the function graph stub. LR
has previously been restored and neither livepatch_handler() nor
ftrace_graph_caller() return back here.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
[mpe: Drop bad change to non-mprofile-kernel version of ftrace_graph_caller]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

parent d08f8a28

arch/powerpc/kernel/entry_64.S

+1 −4

Original line number	Diff line number	Diff line
		@@ -1313,16 +1313,12 @@ ftrace_call:
		#endif

		#ifdef CONFIG_FUNCTION_GRAPH_TRACER
		stdu r1, -112(r1)
		.globl ftrace_graph_call
		ftrace_graph_call:
		b ftrace_graph_stub
		_GLOBAL(ftrace_graph_stub)
		addi r1, r1, 112
		#endif

		ld r0,LRSAVE(r1) /* restore callee's lr at _mcount site */
		mtlr r0
		bctr /* jump after _mcount site */
		#endif /* CC_USING_MPROFILE_KERNEL */

		@@ -1471,6 +1467,7 @@ _GLOBAL(ftrace_graph_caller)

		#else /* CC_USING_MPROFILE_KERNEL */
		_GLOBAL(ftrace_graph_caller)
		stdu r1, -112(r1)
		/* with -mprofile-kernel, parameter regs are still alive at _mcount */
		std r10, 104(r1)
		std r9, 96(r1)

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