Re: [PATCH 1/3] perf tests: Introduce perf_regs_load function on ARM64

Hi WIll, Mark,

Ping on this series. Can you please check? Is the refreshed patch OK?

Cheers, Jean

On 28 April 2014 15:12, Jean Pihet jean.pihet@linaro.org wrote:

Introducing perf_regs_load function, which is going to be used for dwarf unwind test in following patches.

It takes single argument as a pointer to the regs dump buffer and populates it with current registers values, as expected by the perf built-in unwinding test.

Signed-off-by: Jean Pihet jean.pihet@linaro.org Cc: Steve Capper steve.capper@linaro.org Cc: Corey Ashford cjashfor@linux.vnet.ibm.com Cc: Frederic Weisbecker fweisbec@gmail.com Cc: Ingo Molnar mingo@kernel.org Cc: Namhyung Kim namhyung@kernel.org Cc: Paul Mackerras paulus@samba.org Cc: Peter Zijlstra a.p.zijlstra@chello.nl Cc: Arnaldo Carvalho de Melo acme@ghostprotocols.net Cc: David Ahern dsahern@gmail.com Cc: Jiri Olsa jolsa@redhat.com

---

tools/perf/arch/arm64/Makefile | 1 + tools/perf/arch/arm64/include/perf_regs.h | 2 ++ tools/perf/arch/arm64/tests/regs_load.S | 40 +++++++++++++++++++++++++++++++ 3 files changed, 43 insertions(+) create mode 100644 tools/perf/arch/arm64/tests/regs_load.S

diff --git a/tools/perf/arch/arm64/Makefile b/tools/perf/arch/arm64/Makefile index 67e9b3d..9b8f87e 100644 --- a/tools/perf/arch/arm64/Makefile +++ b/tools/perf/arch/arm64/Makefile @@ -4,4 +4,5 @@ LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/dwarf-regs.o endif ifndef NO_LIBUNWIND LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/unwind-libunwind.o +LIB_OBJS += $(OUTPUT)arch/$(ARCH)/tests/regs_load.o endif diff --git a/tools/perf/arch/arm64/include/perf_regs.h b/tools/perf/arch/arm64/include/perf_regs.h index 2359546..1e052f1 100644 --- a/tools/perf/arch/arm64/include/perf_regs.h +++ b/tools/perf/arch/arm64/include/perf_regs.h @@ -9,6 +9,8 @@ #define PERF_REG_IP PERF_REG_ARM64_PC #define PERF_REG_SP PERF_REG_ARM64_SP

+void perf_regs_load(u64 *regs);

static inline const char *perf_reg_name(int id) { switch (id) { diff --git a/tools/perf/arch/arm64/tests/regs_load.S b/tools/perf/arch/arm64/tests/regs_load.S new file mode 100644 index 0000000..40b8b99 --- /dev/null +++ b/tools/perf/arch/arm64/tests/regs_load.S @@ -0,0 +1,40 @@ +#include <linux/linkage.h>

+/*

• • Implementation of void perf_regs_load(u64 *regs);
• • This functions fills in the 'regs' buffer from the actual registers values,
• • in the way the perf built-in unwinding test expects them, e.g. an address
• • within the caller:
• • • the PC at the time at the call to this function. Since this function
• • is called using a bl instruction, the PC value is taken from LR,
• • • the current SP (not touched by this function),
• • • the current value of LR is merely retrieved and stored because the
• • value before the call to this function is unknown at this time; it will
• • be unwound from the dwarf information in unwind__get_entries.
• */

+.text +.type perf_regs_load,%function +ENTRY(perf_regs_load)

•   stp x0,  x1,  [x0], #16 // store x0..x29
  

•   stp x2,  x3,  [x0], #16
  

•   stp x4,  x5,  [x0], #16
  

•   stp x6,  x7,  [x0], #16
  

•   stp x8,  x9,  [x0], #16
  

•   stp x10, x11, [x0], #16
  

•   stp x12, x13, [x0], #16
  

•   stp x14, x15, [x0], #16
  

•   stp x16, x17, [x0], #16
  

•   stp x18, x19, [x0], #16
  

•   stp x20, x21, [x0], #16
  

•   stp x22, x23, [x0], #16
  

•   stp x24, x25, [x0], #16
  

•   stp x26, x27, [x0], #16
  

•   stp x28, x29, [x0], #16
  

•   mov x1,  sp
  

•   stp x30, x1,  [x0], #16 // store lr and sp
  

•   str x30, [x0]           // store lr as the PC in order to skip the call
  

•                           //  to this function
  

•   ret
  

+ENDPROC(perf_regs_load)

1.7.11.7