diff options
Diffstat (limited to 'arch/powerpc/kernel/trace/ftrace_32.S')
| -rw-r--r-- | arch/powerpc/kernel/trace/ftrace_32.S | 118 |
1 files changed, 105 insertions, 13 deletions
diff --git a/arch/powerpc/kernel/trace/ftrace_32.S b/arch/powerpc/kernel/trace/ftrace_32.S index e023ae59c429..0a02c0cb12d9 100644 --- a/arch/powerpc/kernel/trace/ftrace_32.S +++ b/arch/powerpc/kernel/trace/ftrace_32.S @@ -9,55 +9,135 @@ #include <asm/asm-offsets.h> #include <asm/ftrace.h> #include <asm/export.h> +#include <asm/ptrace.h> _GLOBAL(mcount) _GLOBAL(_mcount) /* * It is required that _mcount on PPC32 must preserve the - * link register. But we have r0 to play with. We use r0 + * link register. But we have r12 to play with. We use r12 * to push the return address back to the caller of mcount * into the ctr register, restore the link register and * then jump back using the ctr register. */ - mflr r0 - mtctr r0 - lwz r0, 4(r1) + mflr r12 + mtctr r12 mtlr r0 bctr +EXPORT_SYMBOL(_mcount) _GLOBAL(ftrace_caller) MCOUNT_SAVE_FRAME /* r3 ends up with link register */ subi r3, r3, MCOUNT_INSN_SIZE + lis r5,function_trace_op@ha + lwz r5,function_trace_op@l(r5) + li r6, 0 .globl ftrace_call ftrace_call: bl ftrace_stub nop + MCOUNT_RESTORE_FRAME +ftrace_caller_common: #ifdef CONFIG_FUNCTION_GRAPH_TRACER .globl ftrace_graph_call ftrace_graph_call: b ftrace_graph_stub _GLOBAL(ftrace_graph_stub) #endif - MCOUNT_RESTORE_FRAME /* old link register ends up in ctr reg */ bctr -EXPORT_SYMBOL(_mcount) _GLOBAL(ftrace_stub) blr +_GLOBAL(ftrace_regs_caller) + /* Save the original return address in A's stack frame */ + stw r0,LRSAVE(r1) + + /* Create our stack frame + pt_regs */ + stwu r1,-INT_FRAME_SIZE(r1) + + /* Save all gprs to pt_regs */ + stw r0, GPR0(r1) + stmw r2, GPR2(r1) + + /* Save previous stack pointer (r1) */ + addi r8, r1, INT_FRAME_SIZE + stw r8, GPR1(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 */ + stw r7, _NIP(r1) + /* Save the read LR in pt_regs->link */ + stw r0, _LINK(r1) + + lis r3,function_trace_op@ha + lwz r5,function_trace_op@l(r3) + + /* 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 */ + stw r8, _MSR(r1) + stw r9, _CTR(r1) + stw r10, _XER(r1) + stw 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_regs_call +ftrace_regs_call: + bl ftrace_stub + nop + + /* Load ctr with the possibly modified NIP */ + lwz r3, _NIP(r1) + mtctr r3 + + /* Restore gprs */ + lmw r2, GPR2(r1) + + /* Restore possibly modified LR */ + lwz r0, _LINK(r1) + mtlr r0 + + /* Pop our stack frame */ + addi r1, r1, INT_FRAME_SIZE + + b ftrace_caller_common + #ifdef CONFIG_FUNCTION_GRAPH_TRACER _GLOBAL(ftrace_graph_caller) + stwu r1,-48(r1) + stw r3, 12(r1) + stw r4, 16(r1) + stw r5, 20(r1) + stw r6, 24(r1) + stw r7, 28(r1) + stw r8, 32(r1) + stw r9, 36(r1) + stw r10,40(r1) + addi r5, r1, 48 - /* load r4 with local address */ - lwz r4, 44(r1) + mfctr r4 /* ftrace_caller has moved local addr here */ + stw r4, 44(r1) + mflr r3 /* ftrace_caller has restored LR from stack */ subi r4, r4, MCOUNT_INSN_SIZE - /* Grab the LR out of the caller stack frame */ - lwz r3,52(r1) - bl prepare_ftrace_return nop @@ -66,9 +146,21 @@ _GLOBAL(ftrace_graph_caller) * Change the LR in the callers stack frame to this. */ stw r3,52(r1) + mtlr r3 + lwz r0,44(r1) + mtctr r0 + + lwz r3, 12(r1) + lwz r4, 16(r1) + lwz r5, 20(r1) + lwz r6, 24(r1) + lwz r7, 28(r1) + lwz r8, 32(r1) + lwz r9, 36(r1) + lwz r10,40(r1) + + addi r1, r1, 48 - MCOUNT_RESTORE_FRAME - /* old link register ends up in ctr reg */ bctr _GLOBAL(return_to_handler) |