diff options
Diffstat (limited to 'arch/powerpc/kernel/trace')
| -rw-r--r-- | arch/powerpc/kernel/trace/ftrace_64_mprofile.S | 45 |
1 files changed, 15 insertions, 30 deletions
diff --git a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S index c98e90b4ea7b..b4e2b7165f79 100644 --- a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S +++ b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S @@ -181,34 +181,25 @@ _GLOBAL(ftrace_stub) * - we have no stack frame and can not allocate one * - LR points back to the original caller (in A) * - CTR holds the new NIP in C - * - r0 & r12 are free - * - * r0 can't be used as the base register for a DS-form load or store, so - * we temporarily shuffle r1 (stack pointer) into r0 and then put it back. + * - r0, r11 & r12 are free */ livepatch_handler: CURRENT_THREAD_INFO(r12, r1) - /* Save stack pointer into r0 */ - mr r0, r1 - /* Allocate 3 x 8 bytes */ - ld r1, TI_livepatch_sp(r12) - addi r1, r1, 24 - std r1, TI_livepatch_sp(r12) + ld r11, TI_livepatch_sp(r12) + addi r11, r11, 24 + std r11, TI_livepatch_sp(r12) /* Save toc & real LR on livepatch stack */ - std r2, -24(r1) + std r2, -24(r11) mflr r12 - std r12, -16(r1) + std r12, -16(r11) /* Store stack end marker */ lis r12, STACK_END_MAGIC@h ori r12, r12, STACK_END_MAGIC@l - std r12, -8(r1) - - /* Restore real stack pointer */ - mr r1, r0 + std r12, -8(r11) /* Put ctr in r12 for global entry and branch there */ mfctr r12 @@ -216,36 +207,30 @@ livepatch_handler: /* * Now we are returning from the patched function to the original - * caller A. We are free to use r0 and r12, and we can use r2 until we + * caller A. We are free to use r11, r12 and we can use r2 until we * restore it. */ CURRENT_THREAD_INFO(r12, r1) - /* Save stack pointer into r0 */ - mr r0, r1 - - ld r1, TI_livepatch_sp(r12) + ld r11, TI_livepatch_sp(r12) /* Check stack marker hasn't been trashed */ lis r2, STACK_END_MAGIC@h ori r2, r2, STACK_END_MAGIC@l - ld r12, -8(r1) + ld r12, -8(r11) 1: tdne r12, r2 EMIT_BUG_ENTRY 1b, __FILE__, __LINE__ - 1, 0 /* Restore LR & toc from livepatch stack */ - ld r12, -16(r1) + ld r12, -16(r11) mtlr r12 - ld r2, -24(r1) + ld r2, -24(r11) /* Pop livepatch stack frame */ - CURRENT_THREAD_INFO(r12, r0) - subi r1, r1, 24 - std r1, TI_livepatch_sp(r12) - - /* Restore real stack pointer */ - mr r1, r0 + CURRENT_THREAD_INFO(r12, r1) + subi r11, r11, 24 + std r11, TI_livepatch_sp(r12) /* Return to original caller of live patched function */ blr |