Commit f768a20c authored by Sven Schnelle's avatar Sven Schnelle Committed by Vasily Gorbik
Browse files

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: default avatarSven Schnelle <svens@linux.ibm.com>
Acked-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent 54235d5c

arch/s390/include/asm/ftrace.h

+28 −0
Original line number Diff line number Diff line
@@ -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 */