diff options
Diffstat (limited to 'arch/riscv/kernel/mcount-dyn.S')
| -rw-r--r-- | arch/riscv/kernel/mcount-dyn.S | 264 |
1 files changed, 106 insertions, 158 deletions
diff --git a/arch/riscv/kernel/mcount-dyn.S b/arch/riscv/kernel/mcount-dyn.S index b7561288e8da..48f6c4f7dca0 100644 --- a/arch/riscv/kernel/mcount-dyn.S +++ b/arch/riscv/kernel/mcount-dyn.S @@ -13,7 +13,6 @@ .text -#define FENTRY_RA_OFFSET 8 #define ABI_SIZE_ON_STACK 80 #define ABI_A0 0 #define ABI_A1 8 @@ -56,204 +55,153 @@ addi sp, sp, ABI_SIZE_ON_STACK .endm -#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS - /** -* SAVE_ABI_REGS - save regs against the pt_regs struct -* -* @all: tell if saving all the regs -* -* If all is set, all the regs will be saved, otherwise only ABI -* related regs (a0-a7,epc,ra and optional s0) will be saved. +* SAVE_ABI_REGS - save regs against the ftrace_regs struct * * After the stack is established, * * 0(sp) stores the PC of the traced function which can be accessed -* by &(fregs)->regs->epc in tracing function. Note that the real -* function entry address should be computed with -FENTRY_RA_OFFSET. +* by &(fregs)->epc in tracing function. * * 8(sp) stores the function return address (i.e. parent IP) that -* can be accessed by &(fregs)->regs->ra in tracing function. +* can be accessed by &(fregs)->ra in tracing function. * * The other regs are saved at the respective localtion and accessed -* by the respective pt_regs member. +* by the respective ftrace_regs member. * * Here is the layout of stack for your reference. * * PT_SIZE_ON_STACK -> +++++++++ * + ..... + -* + t3-t6 + -* + s2-s11+ * + a0-a7 + --++++-> ftrace_caller saved -* + s1 + + -* + s0 + --+ -* + t0-t2 + + -* + tp + + -* + gp + + +* + t1 + --++++-> direct tramp address +* + s0 + --+ // frame pointer * + sp + + * + ra + --+ // parent IP * sp -> + epc + --+ // PC * +++++++++ **/ - .macro SAVE_ABI_REGS, all=0 - addi sp, sp, -PT_SIZE_ON_STACK - - REG_S t0, PT_EPC(sp) - REG_S x1, PT_RA(sp) - - // save the ABI regs - - REG_S x10, PT_A0(sp) - REG_S x11, PT_A1(sp) - REG_S x12, PT_A2(sp) - REG_S x13, PT_A3(sp) - REG_S x14, PT_A4(sp) - REG_S x15, PT_A5(sp) - REG_S x16, PT_A6(sp) - REG_S x17, PT_A7(sp) - - // save the leftover regs - - .if \all == 1 - REG_S x2, PT_SP(sp) - REG_S x3, PT_GP(sp) - REG_S x4, PT_TP(sp) - REG_S x5, PT_T0(sp) - REG_S x6, PT_T1(sp) - REG_S x7, PT_T2(sp) - REG_S x8, PT_S0(sp) - REG_S x9, PT_S1(sp) - REG_S x18, PT_S2(sp) - REG_S x19, PT_S3(sp) - REG_S x20, PT_S4(sp) - REG_S x21, PT_S5(sp) - REG_S x22, PT_S6(sp) - REG_S x23, PT_S7(sp) - REG_S x24, PT_S8(sp) - REG_S x25, PT_S9(sp) - REG_S x26, PT_S10(sp) - REG_S x27, PT_S11(sp) - REG_S x28, PT_T3(sp) - REG_S x29, PT_T4(sp) - REG_S x30, PT_T5(sp) - REG_S x31, PT_T6(sp) - - // save s0 if FP_TEST defined - - .else + .macro SAVE_ABI_REGS + addi sp, sp, -FREGS_SIZE_ON_STACK + REG_S t0, FREGS_EPC(sp) + REG_S x1, FREGS_RA(sp) #ifdef HAVE_FUNCTION_GRAPH_FP_TEST - REG_S x8, PT_S0(sp) + REG_S x8, FREGS_S0(sp) #endif - .endif + REG_S x6, FREGS_T1(sp) +#ifdef CONFIG_CC_IS_CLANG + REG_S x7, FREGS_T2(sp) + REG_S x28, FREGS_T3(sp) + REG_S x29, FREGS_T4(sp) + REG_S x30, FREGS_T5(sp) + REG_S x31, FREGS_T6(sp) +#endif + // save the arguments + REG_S x10, FREGS_A0(sp) + REG_S x11, FREGS_A1(sp) + REG_S x12, FREGS_A2(sp) + REG_S x13, FREGS_A3(sp) + REG_S x14, FREGS_A4(sp) + REG_S x15, FREGS_A5(sp) + REG_S x16, FREGS_A6(sp) + REG_S x17, FREGS_A7(sp) + mv a0, sp + addi a0, a0, FREGS_SIZE_ON_STACK + REG_S a0, FREGS_SP(sp) // Put original SP on stack .endm - .macro RESTORE_ABI_REGS, all=0 - REG_L t0, PT_EPC(sp) - REG_L x1, PT_RA(sp) - REG_L x10, PT_A0(sp) - REG_L x11, PT_A1(sp) - REG_L x12, PT_A2(sp) - REG_L x13, PT_A3(sp) - REG_L x14, PT_A4(sp) - REG_L x15, PT_A5(sp) - REG_L x16, PT_A6(sp) - REG_L x17, PT_A7(sp) - - .if \all == 1 - REG_L x2, PT_SP(sp) - REG_L x3, PT_GP(sp) - REG_L x4, PT_TP(sp) - REG_L x6, PT_T1(sp) - REG_L x7, PT_T2(sp) - REG_L x8, PT_S0(sp) - REG_L x9, PT_S1(sp) - REG_L x18, PT_S2(sp) - REG_L x19, PT_S3(sp) - REG_L x20, PT_S4(sp) - REG_L x21, PT_S5(sp) - REG_L x22, PT_S6(sp) - REG_L x23, PT_S7(sp) - REG_L x24, PT_S8(sp) - REG_L x25, PT_S9(sp) - REG_L x26, PT_S10(sp) - REG_L x27, PT_S11(sp) - REG_L x28, PT_T3(sp) - REG_L x29, PT_T4(sp) - REG_L x30, PT_T5(sp) - REG_L x31, PT_T6(sp) - - .else + .macro RESTORE_ABI_REGS + REG_L t0, FREGS_EPC(sp) + REG_L x1, FREGS_RA(sp) #ifdef HAVE_FUNCTION_GRAPH_FP_TEST - REG_L x8, PT_S0(sp) + REG_L x8, FREGS_S0(sp) #endif - .endif - addi sp, sp, PT_SIZE_ON_STACK + REG_L x6, FREGS_T1(sp) +#ifdef CONFIG_CC_IS_CLANG + REG_L x7, FREGS_T2(sp) + REG_L x28, FREGS_T3(sp) + REG_L x29, FREGS_T4(sp) + REG_L x30, FREGS_T5(sp) + REG_L x31, FREGS_T6(sp) +#endif + // restore the arguments + REG_L x10, FREGS_A0(sp) + REG_L x11, FREGS_A1(sp) + REG_L x12, FREGS_A2(sp) + REG_L x13, FREGS_A3(sp) + REG_L x14, FREGS_A4(sp) + REG_L x15, FREGS_A5(sp) + REG_L x16, FREGS_A6(sp) + REG_L x17, FREGS_A7(sp) + + addi sp, sp, FREGS_SIZE_ON_STACK .endm .macro PREPARE_ARGS - addi a0, t0, -FENTRY_RA_OFFSET + addi a0, t0, -MCOUNT_JALR_SIZE // ip (callsite's jalr insn) +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_CALL_OPS + mv a1, ra // parent_ip + REG_L a2, -16(t0) // op + REG_L ra, FTRACE_OPS_FUNC(a2) // op->func +#else la a1, function_trace_op - REG_L a2, 0(a1) - mv a1, ra - mv a3, sp + REG_L a2, 0(a1) // op + mv a1, ra // parent_ip +#endif + mv a3, sp // regs .endm -#endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ - -#ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS SYM_FUNC_START(ftrace_caller) - SAVE_ABI - - addi a0, t0, -FENTRY_RA_OFFSET - la a1, function_trace_op - REG_L a2, 0(a1) - mv a1, ra - mv a3, sp - -SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL) - call ftrace_stub +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_CALL_OPS + /* + * When CALL_OPS is enabled (2 or 4) nops [8B] are placed before the + * function entry, these are later overwritten with the pointer to the + * associated struct ftrace_ops. + * + * -8: &ftrace_ops of the associated tracer function. + *<ftrace enable>: + * 0: auipc t0/ra, 0x? + * 4: jalr t0/ra, ?(t0/ra) + * + * -8: &ftrace_nop_ops + *<ftrace disable>: + * 0: nop + * 4: nop + * + * t0 is set to ip+8 after the jalr is executed at the callsite, + * so we find the associated op at t0-16. + */ + REG_L t1, -16(t0) // op Should be SZ_REG instead of 16 -#ifdef CONFIG_FUNCTION_GRAPH_TRACER - addi a0, sp, ABI_RA - REG_L a1, ABI_T0(sp) - addi a1, a1, -FENTRY_RA_OFFSET -#ifdef HAVE_FUNCTION_GRAPH_FP_TEST - mv a2, s0 +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS + /* + * If the op has a direct call, handle it immediately without + * saving/restoring registers. + */ + REG_L t1, FTRACE_OPS_DIRECT_CALL(t1) + bnez t1, ftrace_caller_direct #endif -SYM_INNER_LABEL(ftrace_graph_call, SYM_L_GLOBAL) - call ftrace_stub #endif - RESTORE_ABI - jr t0 -SYM_FUNC_END(ftrace_caller) - -#else /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ -SYM_FUNC_START(ftrace_regs_caller) - mv t1, zero - SAVE_ABI_REGS 1 - PREPARE_ARGS - -SYM_INNER_LABEL(ftrace_regs_call, SYM_L_GLOBAL) - call ftrace_stub - - RESTORE_ABI_REGS 1 - bnez t1, .Ldirect - jr t0 -.Ldirect: - jr t1 -SYM_FUNC_END(ftrace_regs_caller) - -SYM_FUNC_START(ftrace_caller) - SAVE_ABI_REGS 0 + SAVE_ABI_REGS PREPARE_ARGS +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_CALL_OPS + jalr ra +#else SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL) - call ftrace_stub - - RESTORE_ABI_REGS 0 + REG_L ra, ftrace_call_dest + jalr ra, 0(ra) +#endif + RESTORE_ABI_REGS +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS + bnez t1, ftrace_caller_direct +#endif jr t0 +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS +SYM_INNER_LABEL(ftrace_caller_direct, SYM_L_LOCAL) + jr t1 +#endif SYM_FUNC_END(ftrace_caller) -#endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS SYM_CODE_START(ftrace_stub_direct_tramp) |