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| author |   Sven Schnelle <svens@linux.ibm.com> | 2021-09-24 15:03:07 +0200 |
|---|---|---|
| committer |   Vasily Gorbik <gor@linux.ibm.com> | 2021-10-04 09:49:37 +0200 |
| commit | f768a20c0a6e5f2396b9ab99bbbfd39d91228df9 (patch) | |
| tree | d296e5171468dbb3b150c2d250f104dd7e4d8cb1 /arch | |
| parent | s390/sclp_sd: fix warnings about missing parameter description (diff) | |
| download | linux-dev-f768a20c0a6e5f2396b9ab99bbbfd39d91228df9.tar.xz linux-dev-f768a20c0a6e5f2396b9ab99bbbfd39d91228df9.zip | |
s390/ftrace: add FTRACE_GEN_NOP_ASM macro
FTRACE_GEN_NOP_ASM(name) can be used to generate assembly functions with
the required information added to allow tracing via kprobes/ftrace. It
adds the nop instruction which will be patched by ftrace later. If the
compiler supports -mnop-mcount it will also add an entry to the
__mcount_loc section.
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/s390/include/asm/ftrace.h | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h index e8b460f39c58..d1841f4176be 100644 --- a/arch/s390/include/asm/ftrace.h +++ b/arch/s390/include/asm/ftrace.h @@ -68,4 +68,32 @@ static inline bool arch_syscall_match_sym_name(const char *sym, } #endif /* __ASSEMBLY__ */ + +#ifdef CONFIG_FUNCTION_TRACER + +#define FTRACE_NOP_INSN .word 0xc004, 0x0000, 0x0000 /* brcl 0,0 */ + +#ifndef CC_USING_HOTPATCH + +#define FTRACE_GEN_MCOUNT_RECORD(name) \ + .section __mcount_loc, "a", @progbits; \ + .quad name; \ + .previous; + +#else /* !CC_USING_HOTPATCH */ + +#define FTRACE_GEN_MCOUNT_RECORD(name) + +#endif /* !CC_USING_HOTPATCH */ + +#define FTRACE_GEN_NOP_ASM(name) \ + FTRACE_GEN_MCOUNT_RECORD(name) \ + FTRACE_NOP_INSN + +#else /* CONFIG_FUNCTION_TRACER */ + +#define FTRACE_GEN_NOP_ASM(name) + +#endif /* CONFIG_FUNCTION_TRACER */ + #endif /* _ASM_S390_FTRACE_H */ |