From 096ff2ddba83bf022d593a3096d683e57c4befb0 Mon Sep 17 00:00:00 2001 From: "Naveen N. Rao" Date: Tue, 25 Apr 2017 19:25:54 +0530 Subject: powerpc/ftrace/64: Split further based on -mprofile-kernel Split ftrace_64.S further retaining the core ftrace 64-bit aspects in ftrace_64.S and moving ftrace_caller() and ftrace_graph_caller() into separate files based on -mprofile-kernel. The livepatch routines are all now contained within the mprofile file. Signed-off-by: Naveen N. Rao Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/trace/Makefile | 5 + arch/powerpc/kernel/trace/ftrace_64.S | 306 +------------------------ arch/powerpc/kernel/trace/ftrace_64_mprofile.S | 272 ++++++++++++++++++++++ arch/powerpc/kernel/trace/ftrace_64_pg.S | 68 ++++++ 4 files changed, 346 insertions(+), 305 deletions(-) create mode 100644 arch/powerpc/kernel/trace/ftrace_64_mprofile.S create mode 100644 arch/powerpc/kernel/trace/ftrace_64_pg.S (limited to 'arch') diff --git a/arch/powerpc/kernel/trace/Makefile b/arch/powerpc/kernel/trace/Makefile index 5f5a35254a9b..729dffc5f7bc 100644 --- a/arch/powerpc/kernel/trace/Makefile +++ b/arch/powerpc/kernel/trace/Makefile @@ -11,6 +11,11 @@ endif obj32-$(CONFIG_FUNCTION_TRACER) += ftrace_32.o obj64-$(CONFIG_FUNCTION_TRACER) += ftrace_64.o +ifdef CONFIG_MPROFILE_KERNEL +obj64-$(CONFIG_FUNCTION_TRACER) += ftrace_64_mprofile.o +else +obj64-$(CONFIG_FUNCTION_TRACER) += ftrace_64_pg.o +endif obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o obj-$(CONFIG_FTRACE_SYSCALLS) += ftrace.o diff --git a/arch/powerpc/kernel/trace/ftrace_64.S b/arch/powerpc/kernel/trace/ftrace_64.S index 587e7b5c0aff..e5ccea19821e 100644 --- a/arch/powerpc/kernel/trace/ftrace_64.S +++ b/arch/powerpc/kernel/trace/ftrace_64.S @@ -23,233 +23,7 @@ EXPORT_SYMBOL(_mcount) mtlr r0 bctr -#ifndef CC_USING_MPROFILE_KERNEL -_GLOBAL_TOC(ftrace_caller) - /* Taken from output of objdump from lib64/glibc */ - mflr r3 - ld r11, 0(r1) - stdu r1, -112(r1) - std r3, 128(r1) - ld r4, 16(r11) - subi r3, r3, MCOUNT_INSN_SIZE -.globl ftrace_call -ftrace_call: - bl ftrace_stub - nop -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -.globl ftrace_graph_call -ftrace_graph_call: - b ftrace_graph_stub -_GLOBAL(ftrace_graph_stub) -#endif - ld r0, 128(r1) - mtlr r0 - addi r1, r1, 112 - -#else /* CC_USING_MPROFILE_KERNEL */ -/* - * - * ftrace_caller() is the function that replaces _mcount() when ftrace is - * active. - * - * We arrive here after a function A calls function B, and we are the trace - * function for B. When we enter r1 points to A's stack frame, B has not yet - * had a chance to allocate one yet. - * - * Additionally r2 may point either to the TOC for A, or B, depending on - * whether B did a TOC setup sequence before calling us. - * - * On entry the LR points back to the _mcount() call site, and r0 holds the - * saved LR as it was on entry to B, ie. the original return address at the - * call site in A. - * - * Our job is to save the register state into a struct pt_regs (on the stack) - * and then arrange for the ftrace function to be called. - */ -_GLOBAL(ftrace_caller) - /* Save the original return address in A's stack frame */ - std r0,LRSAVE(r1) - - /* Create our stack frame + pt_regs */ - stdu r1,-SWITCH_FRAME_SIZE(r1) - - /* Save all gprs to pt_regs */ - SAVE_8GPRS(0,r1) - SAVE_8GPRS(8,r1) - SAVE_8GPRS(16,r1) - SAVE_8GPRS(24,r1) - - /* Load special regs for save below */ - mfmsr r8 - mfctr r9 - mfxer r10 - mfcr r11 - - /* Get the _mcount() call site out of LR */ - mflr r7 - /* Save it as pt_regs->nip */ - std r7, _NIP(r1) - /* Save the read LR in pt_regs->link */ - std r0, _LINK(r1) - - /* Save callee's TOC in the ABI compliant location */ - std r2, 24(r1) - ld r2,PACATOC(r13) /* get kernel TOC in r2 */ - - addis r3,r2,function_trace_op@toc@ha - addi r3,r3,function_trace_op@toc@l - ld r5,0(r3) - -#ifdef CONFIG_LIVEPATCH - mr r14,r7 /* remember old NIP */ -#endif - /* Calculate ip from nip-4 into r3 for call below */ - subi r3, r7, MCOUNT_INSN_SIZE - - /* Put the original return address in r4 as parent_ip */ - mr r4, r0 - - /* Save special regs */ - std r8, _MSR(r1) - std r9, _CTR(r1) - std r10, _XER(r1) - std r11, _CCR(r1) - - /* Load &pt_regs in r6 for call below */ - addi r6, r1 ,STACK_FRAME_OVERHEAD - - /* ftrace_call(r3, r4, r5, r6) */ -.globl ftrace_call -ftrace_call: - bl ftrace_stub - nop - - /* Load ctr with the possibly modified NIP */ - ld r3, _NIP(r1) - mtctr r3 -#ifdef CONFIG_LIVEPATCH - cmpd r14,r3 /* has NIP been altered? */ -#endif - - /* Restore gprs */ - REST_8GPRS(0,r1) - REST_8GPRS(8,r1) - REST_8GPRS(16,r1) - REST_8GPRS(24,r1) - - /* Restore possibly modified LR */ - ld r0, _LINK(r1) - mtlr r0 - - /* Restore callee's TOC */ - ld r2, 24(r1) - - /* Pop our stack frame */ - addi r1, r1, SWITCH_FRAME_SIZE - -#ifdef CONFIG_LIVEPATCH - /* Based on the cmpd above, if the NIP was altered handle livepatch */ - bne- livepatch_handler -#endif - -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -.globl ftrace_graph_call -ftrace_graph_call: - b ftrace_graph_stub -_GLOBAL(ftrace_graph_stub) -#endif - - bctr /* jump after _mcount site */ -#endif /* CC_USING_MPROFILE_KERNEL */ - -_GLOBAL(ftrace_stub) - blr - -#ifdef CONFIG_LIVEPATCH - /* - * This function runs in the mcount context, between two functions. As - * such it can only clobber registers which are volatile and used in - * function linkage. - * - * We get here when a function A, calls another function B, but B has - * been live patched with a new function C. - * - * On entry: - * - 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. - */ -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) - - /* Save toc & real LR on livepatch stack */ - std r2, -24(r1) - mflr r12 - std r12, -16(r1) - - /* 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 - - /* Put ctr in r12 for global entry and branch there */ - mfctr r12 - bctrl - - /* - * 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 - * restore it. - */ - - CURRENT_THREAD_INFO(r12, r1) - - /* Save stack pointer into r0 */ - mr r0, r1 - - ld r1, 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) -1: tdne r12, r2 - EMIT_BUG_ENTRY 1b, __FILE__, __LINE__ - 1, 0 - - /* Restore LR & toc from livepatch stack */ - ld r12, -16(r1) - mtlr r12 - ld r2, -24(r1) - - /* 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 - - /* Return to original caller of live patched function */ - blr -#endif - - -#else +#else /* CONFIG_DYNAMIC_FTRACE */ _GLOBAL_TOC(_mcount) EXPORT_SYMBOL(_mcount) /* Taken from output of objdump from lib64/glibc */ @@ -267,7 +41,6 @@ EXPORT_SYMBOL(_mcount) bctrl nop - #ifdef CONFIG_FUNCTION_GRAPH_TRACER b ftrace_graph_caller #endif @@ -276,86 +49,9 @@ EXPORT_SYMBOL(_mcount) addi r1, r1, 112 _GLOBAL(ftrace_stub) blr - #endif /* CONFIG_DYNAMIC_FTRACE */ #ifdef CONFIG_FUNCTION_GRAPH_TRACER -#ifndef CC_USING_MPROFILE_KERNEL -_GLOBAL(ftrace_graph_caller) - /* load r4 with local address */ - ld r4, 128(r1) - subi r4, r4, MCOUNT_INSN_SIZE - - /* Grab the LR out of the caller stack frame */ - ld r11, 112(r1) - ld r3, 16(r11) - - bl prepare_ftrace_return - nop - - /* - * prepare_ftrace_return gives us the address we divert to. - * Change the LR in the callers stack frame to this. - */ - ld r11, 112(r1) - std r3, 16(r11) - - ld r0, 128(r1) - mtlr r0 - addi r1, r1, 112 - blr - -#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) - 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 callee's TOC in the ABI compliant location */ - std r2, 24(r1) - ld r2, PACATOC(r13) /* get kernel TOC in r2 */ - - mfctr r4 /* ftrace_caller has moved local addr here */ - std r4, 40(r1) - mflr r3 /* ftrace_caller has restored LR from stack */ - subi r4, r4, MCOUNT_INSN_SIZE - - bl prepare_ftrace_return - nop - - /* - * prepare_ftrace_return gives us the address we divert to. - * Change the LR to this. - */ - mtlr r3 - - ld r0, 40(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) - - /* Restore callee's TOC */ - ld r2, 24(r1) - - addi r1, r1, 112 - mflr r0 - std r0, LRSAVE(r1) - bctr -#endif /* CC_USING_MPROFILE_KERNEL */ - _GLOBAL(return_to_handler) /* need to save return values */ std r4, -32(r1) diff --git a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S new file mode 100644 index 000000000000..7c933a99f5d5 --- /dev/null +++ b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S @@ -0,0 +1,272 @@ +/* + * Split from ftrace_64.S + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#ifdef CONFIG_DYNAMIC_FTRACE +/* + * + * ftrace_caller() is the function that replaces _mcount() when ftrace is + * active. + * + * We arrive here after a function A calls function B, and we are the trace + * function for B. When we enter r1 points to A's stack frame, B has not yet + * had a chance to allocate one yet. + * + * Additionally r2 may point either to the TOC for A, or B, depending on + * whether B did a TOC setup sequence before calling us. + * + * On entry the LR points back to the _mcount() call site, and r0 holds the + * saved LR as it was on entry to B, ie. the original return address at the + * call site in A. + * + * Our job is to save the register state into a struct pt_regs (on the stack) + * and then arrange for the ftrace function to be called. + */ +_GLOBAL(ftrace_caller) + /* Save the original return address in A's stack frame */ + std r0,LRSAVE(r1) + + /* Create our stack frame + pt_regs */ + stdu r1,-SWITCH_FRAME_SIZE(r1) + + /* Save all gprs to pt_regs */ + SAVE_8GPRS(0,r1) + SAVE_8GPRS(8,r1) + SAVE_8GPRS(16,r1) + SAVE_8GPRS(24,r1) + + /* Load special regs for save below */ + mfmsr r8 + mfctr r9 + mfxer r10 + mfcr r11 + + /* Get the _mcount() call site out of LR */ + mflr r7 + /* Save it as pt_regs->nip */ + std r7, _NIP(r1) + /* Save the read LR in pt_regs->link */ + std r0, _LINK(r1) + + /* Save callee's TOC in the ABI compliant location */ + std r2, 24(r1) + ld r2,PACATOC(r13) /* get kernel TOC in r2 */ + + addis r3,r2,function_trace_op@toc@ha + addi r3,r3,function_trace_op@toc@l + ld r5,0(r3) + +#ifdef CONFIG_LIVEPATCH + mr r14,r7 /* remember old NIP */ +#endif + /* Calculate ip from nip-4 into r3 for call below */ + subi r3, r7, MCOUNT_INSN_SIZE + + /* Put the original return address in r4 as parent_ip */ + mr r4, r0 + + /* Save special regs */ + std r8, _MSR(r1) + std r9, _CTR(r1) + std r10, _XER(r1) + std r11, _CCR(r1) + + /* Load &pt_regs in r6 for call below */ + addi r6, r1 ,STACK_FRAME_OVERHEAD + + /* ftrace_call(r3, r4, r5, r6) */ +.globl ftrace_call +ftrace_call: + bl ftrace_stub + nop + + /* Load ctr with the possibly modified NIP */ + ld r3, _NIP(r1) + mtctr r3 +#ifdef CONFIG_LIVEPATCH + cmpd r14,r3 /* has NIP been altered? */ +#endif + + /* Restore gprs */ + REST_8GPRS(0,r1) + REST_8GPRS(8,r1) + REST_8GPRS(16,r1) + REST_8GPRS(24,r1) + + /* Restore possibly modified LR */ + ld r0, _LINK(r1) + mtlr r0 + + /* Restore callee's TOC */ + ld r2, 24(r1) + + /* Pop our stack frame */ + addi r1, r1, SWITCH_FRAME_SIZE + +#ifdef CONFIG_LIVEPATCH + /* Based on the cmpd above, if the NIP was altered handle livepatch */ + bne- livepatch_handler +#endif + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +.globl ftrace_graph_call +ftrace_graph_call: + b ftrace_graph_stub +_GLOBAL(ftrace_graph_stub) +#endif + + bctr /* jump after _mcount site */ + +_GLOBAL(ftrace_stub) + blr + +#ifdef CONFIG_LIVEPATCH + /* + * This function runs in the mcount context, between two functions. As + * such it can only clobber registers which are volatile and used in + * function linkage. + * + * We get here when a function A, calls another function B, but B has + * been live patched with a new function C. + * + * On entry: + * - 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. + */ +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) + + /* Save toc & real LR on livepatch stack */ + std r2, -24(r1) + mflr r12 + std r12, -16(r1) + + /* 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 + + /* Put ctr in r12 for global entry and branch there */ + mfctr r12 + bctrl + + /* + * 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 + * restore it. + */ + + CURRENT_THREAD_INFO(r12, r1) + + /* Save stack pointer into r0 */ + mr r0, r1 + + ld r1, 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) +1: tdne r12, r2 + EMIT_BUG_ENTRY 1b, __FILE__, __LINE__ - 1, 0 + + /* Restore LR & toc from livepatch stack */ + ld r12, -16(r1) + mtlr r12 + ld r2, -24(r1) + + /* 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 + + /* Return to original caller of live patched function */ + blr +#endif /* CONFIG_LIVEPATCH */ + +#endif /* CONFIG_DYNAMIC_FTRACE */ + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +_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) + 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 callee's TOC in the ABI compliant location */ + std r2, 24(r1) + ld r2, PACATOC(r13) /* get kernel TOC in r2 */ + + mfctr r4 /* ftrace_caller has moved local addr here */ + std r4, 40(r1) + mflr r3 /* ftrace_caller has restored LR from stack */ + subi r4, r4, MCOUNT_INSN_SIZE + + bl prepare_ftrace_return + nop + + /* + * prepare_ftrace_return gives us the address we divert to. + * Change the LR to this. + */ + mtlr r3 + + ld r0, 40(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) + + /* Restore callee's TOC */ + ld r2, 24(r1) + + addi r1, r1, 112 + mflr r0 + std r0, LRSAVE(r1) + bctr +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ diff --git a/arch/powerpc/kernel/trace/ftrace_64_pg.S b/arch/powerpc/kernel/trace/ftrace_64_pg.S new file mode 100644 index 000000000000..f095358da96e --- /dev/null +++ b/arch/powerpc/kernel/trace/ftrace_64_pg.S @@ -0,0 +1,68 @@ +/* + * Split from ftrace_64.S + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include +#include +#include +#include +#include +#include + +#ifdef CONFIG_DYNAMIC_FTRACE +_GLOBAL_TOC(ftrace_caller) + /* Taken from output of objdump from lib64/glibc */ + mflr r3 + ld r11, 0(r1) + stdu r1, -112(r1) + std r3, 128(r1) + ld r4, 16(r11) + subi r3, r3, MCOUNT_INSN_SIZE +.globl ftrace_call +ftrace_call: + bl ftrace_stub + nop +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +.globl ftrace_graph_call +ftrace_graph_call: + b ftrace_graph_stub +_GLOBAL(ftrace_graph_stub) +#endif + ld r0, 128(r1) + mtlr r0 + addi r1, r1, 112 + +_GLOBAL(ftrace_stub) + blr +#endif /* CONFIG_DYNAMIC_FTRACE */ + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +_GLOBAL(ftrace_graph_caller) + /* load r4 with local address */ + ld r4, 128(r1) + subi r4, r4, MCOUNT_INSN_SIZE + + /* Grab the LR out of the caller stack frame */ + ld r11, 112(r1) + ld r3, 16(r11) + + bl prepare_ftrace_return + nop + + /* + * prepare_ftrace_return gives us the address we divert to. + * Change the LR in the callers stack frame to this. + */ + ld r11, 112(r1) + std r3, 16(r11) + + ld r0, 128(r1) + mtlr r0 + addi r1, r1, 112 + blr +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ -- cgit v1.2.3-59-g8ed1b