On Sat, Mar 15, 2014 at 05:45:52AM +0000, AKASHI Takahiro wrote:
CALLER_ADDRx returns caller's address at specified level in call stacks. They are used for several tracers like irqsoff and preemptoff. Strange to say, however, they are refered even without FTRACE.
Signed-off-by: AKASHI Takahiro takahiro.akashi@linaro.org
arch/arm64/include/asm/ftrace.h | 13 ++++++++- arch/arm64/kernel/Makefile | 3 ++- arch/arm64/kernel/return_address.c | 55 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 69 insertions(+), 2 deletions(-) create mode 100644 arch/arm64/kernel/return_address.c
diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h index ed5c448..c44c4b1 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -18,6 +18,7 @@ #ifndef __ASSEMBLY__ extern void _mcount(unsigned long); +extern void *return_address(unsigned int); struct dyn_arch_ftrace { /* No extra data needed for arm64 */ @@ -33,6 +34,16 @@ static inline unsigned long ftrace_call_adjust(unsigned long addr) */ return addr; } -#endif /* __ASSEMBLY__ */
+#define HAVE_ARCH_CALLER_ADDR
+#define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0)) +#define CALLER_ADDR1 ((unsigned long)return_address(1)) +#define CALLER_ADDR2 ((unsigned long)return_address(2)) +#define CALLER_ADDR3 ((unsigned long)return_address(3)) +#define CALLER_ADDR4 ((unsigned long)return_address(4)) +#define CALLER_ADDR5 ((unsigned long)return_address(5)) +#define CALLER_ADDR6 ((unsigned long)return_address(6)) +#endif /* ifndef __ASSEMBLY__ */
Hmm, I thought you were going to take a look at reworking the core code for this, as Steve and I suggested?
http://lists.infradead.org/pipermail/linux-arm-kernel/2014-March/240239.html
Will