[PATCH 2/3] perf tests: Add dwarf unwind test on ARM

From: Jean Pihet
Date: Tue May 06 2014 - 11:27:13 EST


Adding dwarf unwind test, that setups live machine data over
the perf test thread and does the remote unwind.

Need to use -fno-optimize-sibling-calls for test compilation,
otherwise 'krava_*' function calls are optimized into jumps
and ommited from the stack unwind.

So far it was enabled only for x86.

Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Corey Ashford <cjashfor@xxxxxxxxxxxxxxxxxx>
Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Signed-off-by: Jean Pihet <jean.pihet@xxxxxxxxxx>
---
tools/perf/Makefile.perf | 2 +-
tools/perf/arch/arm/Makefile | 1 +
tools/perf/arch/arm/include/perf_regs.h | 3 ++
tools/perf/arch/arm/tests/dwarf-unwind.c | 59 ++++++++++++++++++++++++++++++++
tools/perf/tests/builtin-test.c | 2 +-
tools/perf/tests/tests.h | 2 +-
6 files changed, 66 insertions(+), 3 deletions(-)
create mode 100644 tools/perf/arch/arm/tests/dwarf-unwind.c

diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
index 2baf61c..dea2d633 100644
--- a/tools/perf/Makefile.perf
+++ b/tools/perf/Makefile.perf
@@ -411,7 +411,7 @@ LIB_OBJS += $(OUTPUT)tests/code-reading.o
LIB_OBJS += $(OUTPUT)tests/sample-parsing.o
LIB_OBJS += $(OUTPUT)tests/parse-no-sample-id-all.o
ifndef NO_DWARF_UNWIND
-ifeq ($(ARCH),x86)
+ifeq ($(ARCH),$(filter $(ARCH),x86 arm))
LIB_OBJS += $(OUTPUT)tests/dwarf-unwind.o
endif
endif
diff --git a/tools/perf/arch/arm/Makefile b/tools/perf/arch/arm/Makefile
index 9b8f87e..221f21d 100644
--- a/tools/perf/arch/arm/Makefile
+++ b/tools/perf/arch/arm/Makefile
@@ -5,4 +5,5 @@ endif
ifndef NO_LIBUNWIND
LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/unwind-libunwind.o
LIB_OBJS += $(OUTPUT)arch/$(ARCH)/tests/regs_load.o
+LIB_OBJS += $(OUTPUT)arch/$(ARCH)/tests/dwarf-unwind.o
endif
diff --git a/tools/perf/arch/arm/include/perf_regs.h b/tools/perf/arch/arm/include/perf_regs.h
index 1476ae7..c2cefff 100644
--- a/tools/perf/arch/arm/include/perf_regs.h
+++ b/tools/perf/arch/arm/include/perf_regs.h
@@ -8,6 +8,9 @@
void perf_regs_load(u64 *regs);

#define PERF_REGS_MASK ((1ULL << PERF_REG_ARM_MAX) - 1)
+#define PERF_REGS_MAX PERF_REG_ARM_MAX
+#define PERF_SAMPLE_REGS_ABI PERF_SAMPLE_REGS_ABI_32
+
#define PERF_REG_IP PERF_REG_ARM_PC
#define PERF_REG_SP PERF_REG_ARM_SP

diff --git a/tools/perf/arch/arm/tests/dwarf-unwind.c b/tools/perf/arch/arm/tests/dwarf-unwind.c
new file mode 100644
index 0000000..d618f5f
--- /dev/null
+++ b/tools/perf/arch/arm/tests/dwarf-unwind.c
@@ -0,0 +1,59 @@
+#include <string.h>
+#include "perf_regs.h"
+#include "thread.h"
+#include "map.h"
+#include "event.h"
+#include "tests/tests.h"
+
+#define STACK_SIZE 8192
+
+static int sample_ustack(struct perf_sample *sample,
+ struct thread *thread, u64 *regs)
+{
+ struct stack_dump *stack = &sample->user_stack;
+ struct map *map;
+ unsigned long sp;
+ u64 stack_size, *buf;
+
+ buf = malloc(STACK_SIZE);
+ if (!buf) {
+ pr_debug("failed to allocate sample uregs data\n");
+ return -1;
+ }
+
+ sp = (unsigned long) regs[PERF_REG_ARM_SP];
+
+ map = map_groups__find(&thread->mg, MAP__FUNCTION, (u64) sp);
+ if (!map) {
+ pr_debug("failed to get stack map\n");
+ return -1;
+ }
+
+ stack_size = map->end - sp;
+ stack_size = stack_size > STACK_SIZE ? STACK_SIZE : stack_size;
+
+ memcpy(buf, (void *) sp, stack_size);
+ stack->data = (char *) buf;
+ stack->size = stack_size;
+ return 0;
+}
+
+int test__arch_unwind_sample(struct perf_sample *sample,
+ struct thread *thread)
+{
+ struct regs_dump *regs = &sample->user_regs;
+ u64 *buf;
+
+ buf = malloc(sizeof(u64) * PERF_REGS_MAX);
+ if (!buf) {
+ pr_debug("failed to allocate sample uregs data\n");
+ return -1;
+ }
+
+ perf_regs_load(buf);
+ regs->abi = PERF_SAMPLE_REGS_ABI;
+ regs->regs = buf;
+ regs->mask = PERF_REGS_MASK;
+
+ return sample_ustack(sample, thread, buf);
+}
diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
index 0d5afaf..5e0764b 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -115,7 +115,7 @@ static struct test {
.desc = "Test parsing with no sample_id_all bit set",
.func = test__parse_no_sample_id_all,
},
-#if defined(__x86_64__) || defined(__i386__)
+#if defined(__x86_64__) || defined(__i386__) || defined(__arm__)
#ifdef HAVE_DWARF_UNWIND_SUPPORT
{
.desc = "Test dwarf unwind",
diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h
index a9d7cb0..8f91fb0 100644
--- a/tools/perf/tests/tests.h
+++ b/tools/perf/tests/tests.h
@@ -45,7 +45,7 @@ int test__hists_filter(void);
int test__mmap_thread_lookup(void);
int test__thread_mg_share(void);

-#if defined(__x86_64__) || defined(__i386__)
+#if defined(__x86_64__) || defined(__i386__) || defined(__arm__)
#ifdef HAVE_DWARF_UNWIND_SUPPORT
struct thread;
struct perf_sample;
--
1.7.11.7

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