From 3b6c52b5b634ae41d762cb174465272d69198160 Mon Sep 17 00:00:00 2001 From: Cyrill Gorcunov Date: Sun, 23 Nov 2008 20:21:39 +0300 Subject: [PATCH] x86: introduce ENTRY(KPROBE_ENTRY)_X86 assembly helpers to catch unbalanced declaration v3 Impact: make ENTRY()/END() macros more capable It's usefull to catch unbalanced or messed or mixed declarations of ENTRY and KPROBES. These macros would help a bit. For example the following code would compile without problems ENTRY_X86(mcount) retq END_X86(mcount) But if you forget and mess the following form ENTRY_X86(mcount) retq END(mcount) ENTRY_X86(ftrace_caller) The assembler will issue the following message: Error: ENTRY_X86/KPROBE_X86 unbalanced,missed,mixed Actually the checking is performed at every _X86 macro so maybe it's good idea to put ENTRY_KPROBE_FINAL_X86 at the end of .S file to be sure you didn't miss anything. Signed-off-by: Cyrill Gorcunov Cc: Alexander van Heukelum Signed-off-by: Ingo Molnar --- arch/x86/include/asm/linkage.h | 60 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) diff --git a/arch/x86/include/asm/linkage.h b/arch/x86/include/asm/linkage.h index f61ee8f937e..5d98d0b68ff 100644 --- a/arch/x86/include/asm/linkage.h +++ b/arch/x86/include/asm/linkage.h @@ -57,5 +57,65 @@ #define __ALIGN_STR ".align 16,0x90" #endif +/* + * to check ENTRY_X86/END_X86 and + * KPROBE_ENTRY_X86/KPROBE_END_X86 + * unbalanced-missed-mixed appearance + */ +#define __set_entry_x86 .set ENTRY_X86_IN, 0 +#define __unset_entry_x86 .set ENTRY_X86_IN, 1 +#define __set_kprobe_x86 .set KPROBE_X86_IN, 0 +#define __unset_kprobe_x86 .set KPROBE_X86_IN, 1 + +#define __macro_err_x86 .error "ENTRY_X86/KPROBE_X86 unbalanced,missed,mixed" + +#define __check_entry_x86 \ + .ifdef ENTRY_X86_IN; \ + .ifeq ENTRY_X86_IN; \ + __macro_err_x86; \ + .abort; \ + .endif; \ + .endif + +#define __check_kprobe_x86 \ + .ifdef KPROBE_X86_IN; \ + .ifeq KPROBE_X86_IN; \ + __macro_err_x86; \ + .abort; \ + .endif; \ + .endif + +#define __check_entry_kprobe_x86 \ + __check_entry_x86; \ + __check_kprobe_x86 + +#define ENTRY_KPROBE_FINAL_X86 __check_entry_kprobe_x86 + +#define ENTRY_X86(name) \ + __check_entry_kprobe_x86; \ + __set_entry_x86; \ + .globl name; \ + __ALIGN; \ + name: + +#define END_X86(name) \ + __unset_entry_x86; \ + __check_entry_kprobe_x86; \ + .size name, .-name + +#define KPROBE_ENTRY_X86(name) \ + __check_entry_kprobe_x86; \ + __set_kprobe_x86; \ + .pushsection .kprobes.text, "ax"; \ + .globl name; \ + __ALIGN; \ + name: + +#define KPROBE_END_X86(name) \ + __unset_kprobe_x86; \ + __check_entry_kprobe_x86; \ + .size name, .-name; \ + .popsection + #endif /* _ASM_X86_LINKAGE_H */ -- 2.11.4.GIT