diff mbox

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

Message ID 1398690730-5454-1-git-send-email-jean.pihet@linaro.org
State New
Headers show

Commit Message

Jean Pihet April 28, 2014, 1:12 p.m. UTC 
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

Comments

Jean Pihet May 2, 2014, 9:19 a.m. UTC | #1 
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
>
Will Deacon May 2, 2014, 4:51 p.m. UTC | #2 
On Fri, May 02, 2014 at 10:19:38AM +0100, Jean Pihet wrote:
> Hi WIll, Mark,
> 
> Ping on this series. Can you please check? Is the refreshed patch OK?

Fine by me, as long as it's not reused outside of this test :)

Will
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diff mbox

Patch

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)