diff options
| -rw-r--r-- | arch/x86/Kconfig | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/ftrace_32.S | 82 |
2 files changed, 73 insertions, 11 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index cc98d5a294ee..8c17146427ca 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -127,7 +127,7 @@ config X86 select HAVE_EBPF_JIT if X86_64 select HAVE_EFFICIENT_UNALIGNED_ACCESS select HAVE_EXIT_THREAD - select HAVE_FENTRY if X86_64 + select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FUNCTION_GRAPH_TRACER select HAVE_FUNCTION_TRACER diff --git a/arch/x86/kernel/ftrace_32.S b/arch/x86/kernel/ftrace_32.S index 93e26647c3f2..80518ec5b882 100644 --- a/arch/x86/kernel/ftrace_32.S +++ b/arch/x86/kernel/ftrace_32.S @@ -9,26 +9,68 @@ #include <asm/ftrace.h> #ifdef CONFIG_FUNCTION_TRACER + +#ifdef CC_USING_FENTRY +# define function_hook __fentry__ +EXPORT_SYMBOL(__fentry__) +#else +# define function_hook mcount +EXPORT_SYMBOL(mcount) +#endif + #ifdef CONFIG_DYNAMIC_FTRACE -ENTRY(mcount) +/* mcount uses a frame pointer even if CONFIG_FRAME_POINTER is not set */ +#if !defined(CC_USING_FENTRY) || defined(CONFIG_FRAME_POINTER) +# define USING_FRAME_POINTER +#endif + +#ifdef USING_FRAME_POINTER +# define MCOUNT_FRAME 1 /* using frame = true */ +#else +# define MCOUNT_FRAME 0 /* using frame = false */ +#endif + +ENTRY(function_hook) ret -END(mcount) +END(function_hook) ENTRY(ftrace_caller) +#ifdef USING_FRAME_POINTER +# ifdef CC_USING_FENTRY + /* + * Frame pointers are of ip followed by bp. + * Since fentry is an immediate jump, we are left with + * parent-ip, function-ip. We need to add a frame with + * parent-ip followed by ebp. + */ + pushl 4(%esp) /* parent ip */ pushl %ebp movl %esp, %ebp - + pushl 2*4(%esp) /* function ip */ +# endif + /* For mcount, the function ip is directly above */ + pushl %ebp + movl %esp, %ebp +#endif pushl %eax pushl %ecx pushl %edx pushl $0 /* Pass NULL as regs pointer */ - movl 5*4(%esp), %eax - /* Copy original ebp into %edx */ + +#ifdef USING_FRAME_POINTER + /* Load parent ebp into edx */ movl 4*4(%esp), %edx +#else + /* There's no frame pointer, load the appropriate stack addr instead */ + lea 4*4(%esp), %edx +#endif + + movl (MCOUNT_FRAME+4)*4(%esp), %eax /* load the rip */ /* Get the parent ip */ - movl 0x4(%edx), %edx + movl 4(%edx), %edx /* edx has ebp */ + movl function_trace_op, %ecx subl $MCOUNT_INSN_SIZE, %eax @@ -40,7 +82,14 @@ ftrace_call: popl %edx popl %ecx popl %eax +#ifdef USING_FRAME_POINTER popl %ebp +# ifdef CC_USING_FENTRY + addl $4,%esp /* skip function ip */ + popl %ebp /* this is the orig bp */ + addl $4, %esp /* skip parent ip */ +# endif +#endif .Lftrace_ret: #ifdef CONFIG_FUNCTION_GRAPH_TRACER .globl ftrace_graph_call @@ -81,6 +130,10 @@ ENTRY(ftrace_regs_caller) pushl %edx pushl %ecx pushl %ebx +#ifdef CC_USING_FENTRY + /* Load 4 off of the parent ip addr into ebp */ + lea 14*4(%esp), %ebp +#endif movl 12*4(%esp), %eax /* Load ip (1st parameter) */ subl $MCOUNT_INSN_SIZE, %eax /* Adjust ip */ @@ -119,7 +172,7 @@ GLOBAL(ftrace_regs_call) jmp .Lftrace_ret #else /* ! CONFIG_DYNAMIC_FTRACE */ -ENTRY(mcount) +ENTRY(function_hook) cmpl $__PAGE_OFFSET, %esp jb ftrace_stub /* Paging not enabled yet? */ @@ -151,9 +204,8 @@ ftrace_stub: popl %ecx popl %eax jmp ftrace_stub -END(mcount) +END(function_hook) #endif /* CONFIG_DYNAMIC_FTRACE */ -EXPORT_SYMBOL(mcount) #endif /* CONFIG_FUNCTION_TRACER */ #ifdef CONFIG_FUNCTION_GRAPH_TRACER @@ -161,9 +213,15 @@ ENTRY(ftrace_graph_caller) pushl %eax pushl %ecx pushl %edx - movl 0xc(%esp), %eax + movl 3*4(%esp), %eax + /* Even with frame pointers, fentry doesn't have one here */ +#ifdef CC_USING_FENTRY + lea 4*4(%esp), %edx + movl $0, %ecx +#else lea 0x4(%ebp), %edx movl (%ebp), %ecx +#endif subl $MCOUNT_INSN_SIZE, %eax call prepare_ftrace_return popl %edx @@ -176,7 +234,11 @@ END(ftrace_graph_caller) return_to_handler: pushl %eax pushl %edx +#ifdef CC_USING_FENTRY + movl $0, %eax +#else movl %ebp, %eax +#endif call ftrace_return_to_handler movl %eax, %ecx popl %edx |