Use SAVE_8GPRS(), REST_8GPRS() and _NIP(), along with using the standard
SWITCH_FRAME_SIZE for the stack frame in ftrace_graph_caller() to
simplify code. This increases the stack frame size, but it is unlikely
to be an issue since ftrace_[regs_]caller() have just used a similar
stack frame size, and it isn't evident that the graph caller has too
deep a call stack to cause issues.
Signed-off-by: Naveen N. Rao <naveen.n....@linux.vnet.ibm.com>
---
.../powerpc/kernel/trace/ftrace_64_mprofile.S | 28 +++++--------------
1 file changed, 7 insertions(+), 21 deletions(-)
diff --git a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
index f9fd5f743eba34..bbe871b47ade58 100644
--- a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
+++ b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
@@ -279,24 +279,17 @@ livepatch_handler:
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
_GLOBAL(ftrace_graph_caller)
- stdu r1, -112(r1)
+ stdu r1,-SWITCH_FRAME_SIZE(r1)
/* with -mprofile-kernel, parameter regs are still alive at _mcount */
- std r10, 104(r1)
- std r9, 96(r1)
- std r8, 88(r1)
- std r7, 80(r1)
- std r6, 72(r1)
- std r5, 64(r1)
- std r4, 56(r1)
- std r3, 48(r1)
+ SAVE_8GPRS(3, r1)
/* Save callee's TOC in the ABI compliant location */
std r2, 24(r1)
ld r2, PACATOC(r13) /* get kernel TOC in r2 */
- addi r5, r1, 112
+ addi r5, r1, SWITCH_FRAME_SIZE
mfctr r4 /* ftrace_caller has moved local addr here */
- std r4, 40(r1)
+ std r4, _NIP(r1)
mflr r3 /* ftrace_caller has restored LR from stack */
subi r4, r4, MCOUNT_INSN_SIZE
@@ -309,21 +302,14 @@ _GLOBAL(ftrace_graph_caller)
*/
mtlr r3
- ld r0, 40(r1)
+ ld r0, _NIP(r1)
mtctr r0
- ld r10, 104(r1)
- ld r9, 96(r1)
- ld r8, 88(r1)
- ld r7, 80(r1)
- ld r6, 72(r1)
- ld r5, 64(r1)
- ld r4, 56(r1)
- ld r3, 48(r1)
+ REST_8GPRS(3, r1)
/* Restore callee's TOC */
ld r2, 24(r1)
- addi r1, r1, 112
+ addi r1, r1, SWITCH_FRAME_SIZE
mflr r0
std r0, LRSAVE(r1)
bctr
--
2.25.4
