diff options
Diffstat (limited to 'arch/x86/kernel/ftrace_64.S')
| -rw-r--r-- | arch/x86/kernel/ftrace_64.S | 61 |
1 files changed, 29 insertions, 32 deletions
diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S index 369e61faacfe..ac3d5f22fe64 100644 --- a/arch/x86/kernel/ftrace_64.S +++ b/arch/x86/kernel/ftrace_64.S @@ -12,7 +12,7 @@ #include <asm/frame.h> .code64 - .section .entry.text, "ax" + .section .text, "ax" #ifdef CONFIG_FRAME_POINTER /* Save parent and function stack frames (rip and rbp) */ @@ -23,7 +23,7 @@ #endif /* CONFIG_FRAME_POINTER */ /* Size of stack used to save mcount regs in save_mcount_regs */ -#define MCOUNT_REG_SIZE (SS+8 + MCOUNT_FRAME_SIZE) +#define MCOUNT_REG_SIZE (FRAME_SIZE + MCOUNT_FRAME_SIZE) /* * gcc -pg option adds a call to 'mcount' in most functions. @@ -77,7 +77,7 @@ /* * We add enough stack to save all regs. */ - subq $(MCOUNT_REG_SIZE - MCOUNT_FRAME_SIZE), %rsp + subq $(FRAME_SIZE), %rsp movq %rax, RAX(%rsp) movq %rcx, RCX(%rsp) movq %rdx, RDX(%rsp) @@ -157,8 +157,12 @@ SYM_INNER_LABEL(ftrace_call, SYM_L_GLOBAL) * think twice before adding any new code or changing the * layout here. */ -SYM_INNER_LABEL(ftrace_epilogue, SYM_L_GLOBAL) +SYM_INNER_LABEL(ftrace_caller_end, SYM_L_GLOBAL) + jmp ftrace_epilogue +SYM_FUNC_END(ftrace_caller); + +SYM_FUNC_START(ftrace_epilogue) #ifdef CONFIG_FUNCTION_GRAPH_TRACER SYM_INNER_LABEL(ftrace_graph_call, SYM_L_GLOBAL) jmp ftrace_stub @@ -170,14 +174,12 @@ SYM_INNER_LABEL(ftrace_graph_call, SYM_L_GLOBAL) */ SYM_INNER_LABEL_ALIGN(ftrace_stub, SYM_L_WEAK) retq -SYM_FUNC_END(ftrace_caller) +SYM_FUNC_END(ftrace_epilogue) SYM_FUNC_START(ftrace_regs_caller) /* Save the current flags before any operations that can change them */ pushfq - UNWIND_HINT_SAVE - /* added 8 bytes to save flags */ save_mcount_regs 8 /* save_mcount_regs fills in first two parameters */ @@ -233,31 +235,16 @@ SYM_INNER_LABEL(ftrace_regs_call, SYM_L_GLOBAL) movq ORIG_RAX(%rsp), %rax movq %rax, MCOUNT_REG_SIZE-8(%rsp) - /* If ORIG_RAX is anything but zero, make this a call to that */ - movq ORIG_RAX(%rsp), %rax - cmpq $0, %rax - je 1f - - /* Swap the flags with orig_rax */ - movq MCOUNT_REG_SIZE(%rsp), %rdi - movq %rdi, MCOUNT_REG_SIZE-8(%rsp) - movq %rax, MCOUNT_REG_SIZE(%rsp) - - restore_mcount_regs 8 - - jmp 2f - -1: restore_mcount_regs - - -2: /* - * The stack layout is nondetermistic here, depending on which path was - * taken. This confuses objtool and ORC, rightfully so. For now, - * pretend the stack always looks like the non-direct case. + * If ORIG_RAX is anything but zero, make this a call to that. + * See arch_ftrace_set_direct_caller(). */ - UNWIND_HINT_RESTORE + movq ORIG_RAX(%rsp), %rax + testq %rax, %rax +SYM_INNER_LABEL(ftrace_regs_caller_jmp, SYM_L_GLOBAL) + jnz 1f + restore_mcount_regs /* Restore flags */ popfq @@ -268,9 +255,19 @@ SYM_INNER_LABEL(ftrace_regs_call, SYM_L_GLOBAL) * to the return. */ SYM_INNER_LABEL(ftrace_regs_caller_end, SYM_L_GLOBAL) - jmp ftrace_epilogue + /* Swap the flags with orig_rax */ +1: movq MCOUNT_REG_SIZE(%rsp), %rdi + movq %rdi, MCOUNT_REG_SIZE-8(%rsp) + movq %rax, MCOUNT_REG_SIZE(%rsp) + + restore_mcount_regs 8 + /* Restore flags */ + popfq + UNWIND_HINT_RET_OFFSET + jmp ftrace_epilogue + SYM_FUNC_END(ftrace_regs_caller) @@ -303,7 +300,7 @@ trace: * function tracing is enabled. */ movq ftrace_trace_function, %r8 - CALL_NOSPEC %r8 + CALL_NOSPEC r8 restore_mcount_regs jmp fgraph_trace @@ -340,6 +337,6 @@ SYM_CODE_START(return_to_handler) movq 8(%rsp), %rdx movq (%rsp), %rax addq $24, %rsp - JMP_NOSPEC %rdi + JMP_NOSPEC rdi SYM_CODE_END(return_to_handler) #endif |