Implement the DYNAMIC_FTRACE_WITH_JMP for x86_64. In ftrace_call_replace, we will use JMP32_INSN_OPCODE instead of CALL_INSN_OPCODE if the address should use "jmp".
Meanwhile, adjust the direct call in the ftrace_regs_caller. Signed-off-by: Menglong Dong <[email protected]> --- arch/x86/Kconfig | 1 + arch/x86/kernel/ftrace.c | 7 ++++++- arch/x86/kernel/ftrace_64.S | 12 +++++++++++- 3 files changed, 18 insertions(+), 2 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index fa3b616af03a..462250a20311 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -230,6 +230,7 @@ config X86 select HAVE_DYNAMIC_FTRACE_WITH_ARGS if X86_64 select HAVE_FTRACE_REGS_HAVING_PT_REGS if X86_64 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS + select HAVE_DYNAMIC_FTRACE_WITH_JMP if X86_64 select HAVE_SAMPLE_FTRACE_DIRECT if X86_64 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI if X86_64 select HAVE_EBPF_JIT diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 4450acec9390..0543b57f54ee 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -74,7 +74,12 @@ static const char *ftrace_call_replace(unsigned long ip, unsigned long addr) * No need to translate into a callthunk. The trampoline does * the depth accounting itself. */ - return text_gen_insn(CALL_INSN_OPCODE, (void *)ip, (void *)addr); + if (ftrace_is_jmp(addr)) { + addr = ftrace_jmp_get(addr); + return text_gen_insn(JMP32_INSN_OPCODE, (void *)ip, (void *)addr); + } else { + return text_gen_insn(CALL_INSN_OPCODE, (void *)ip, (void *)addr); + } } static int ftrace_verify_code(unsigned long ip, const char *old_code) diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S index 367da3638167..068242e9c857 100644 --- a/arch/x86/kernel/ftrace_64.S +++ b/arch/x86/kernel/ftrace_64.S @@ -285,8 +285,18 @@ SYM_INNER_LABEL(ftrace_regs_caller_end, SYM_L_GLOBAL) ANNOTATE_NOENDBR RET +1: + testb $1, %al + jz 2f + andq $0xfffffffffffffffe, %rax + movq %rax, MCOUNT_REG_SIZE+8(%rsp) + restore_mcount_regs + /* Restore flags */ + popfq + RET + /* Swap the flags with orig_rax */ -1: movq MCOUNT_REG_SIZE(%rsp), %rdi +2: movq MCOUNT_REG_SIZE(%rsp), %rdi movq %rdi, MCOUNT_REG_SIZE-8(%rsp) movq %rax, MCOUNT_REG_SIZE(%rsp) -- 2.51.2
