[PATCH v5 4/4] perf tools: Support "branch-misses:pp" on arm64

James Clark
2020-02-25T11:58:00Z

From: Tan Xiaojun <tanxiaojun@huawei.com>

At the suggestion of James Clark, use spe to support the precise
ip of some events. Currently its support event is:
branch-misses.

Example usage:

$ ./perf record -e branch-misses:pp dd if=/dev/zero of=/dev/null count=10000
(:p/pp/ppp is same for this case.)

$ ./perf report --stdio
("--stdio is not necessary")

--------------------------------------------------------------------
...
# Samples: 14 of event 'branch-misses:pp'
# Event count (approx.): 14
#
# Children Self Command Shared Object Symbol
# ........ ........ ....... ................. ..........................
#
14.29% 14.29% dd [kernel.kallsyms] [k] __arch_copy_from_user
14.29% 14.29% dd libc-2.28.so [.] _dl_addr
7.14% 7.14% dd [kernel.kallsyms] [k] __free_pages
7.14% 7.14% dd [kernel.kallsyms] [k] __pi_memcpy
7.14% 7.14% dd [kernel.kallsyms] [k] pagecache_get_page
7.14% 7.14% dd [kernel.kallsyms] [k] unmap_single_vma
7.14% 7.14% dd dd [.] 0x00000000000025ec
7.14% 7.14% dd ld-2.28.so [.] _dl_lookup_symbol_x
7.14% 7.14% dd ld-2.28.so [.] check_match
7.14% 7.14% dd libc-2.28.so [.] __mpn_rshift
7.14% 7.14% dd libc-2.28.so [.] _nl_intern_locale_data
7.14% 7.14% dd libc-2.28.so [.] read_alias_file
...
--------------------------------------------------------------------

Signed-off-by: Tan Xiaojun <tanxiaojun@huawei.com>
Suggested-by: James Clark <James.Clark@arm.com>
Tested-by: Qi Liu <liuqi115@hisilicon.com>
Signed-off-by: James Clark <james.clark@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Tan Xiaojun <tanxiaojun@huawei.com>
Cc: Al Grant <al.grant@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
---
tools/perf/arch/arm/util/auxtrace.c | 39 +++++++++++++++++++++++++++++
tools/perf/builtin-record.c | 5 ++++
tools/perf/util/arm-spe.c | 9 +++++++
tools/perf/util/arm-spe.h | 3 +++
tools/perf/util/auxtrace.h | 6 +++++
5 files changed, 62 insertions(+)

diff --git a/tools/perf/arch/arm/util/auxtrace.c b/tools/perf/arch/arm/util/auxtrace.c
index 0a6e75b8777a..7f412b7894ab 100644
--- a/tools/perf/arch/arm/util/auxtrace.c
+++ b/tools/perf/arch/arm/util/auxtrace.c
@@ -10,11 +10,25 @@

#include "../../util/auxtrace.h"
#include "../../util/debug.h"
+#include "../../util/env.h"
#include "../../util/evlist.h"
#include "../../util/pmu.h"
#include "cs-etm.h"
#include "arm-spe.h"

+#define SPE_ATTR_TS_ENABLE BIT(0)
+#define SPE_ATTR_PA_ENABLE BIT(1)
+#define SPE_ATTR_PCT_ENABLE BIT(2)
+#define SPE_ATTR_JITTER BIT(16)
+#define SPE_ATTR_BRANCH_FILTER BIT(32)
+#define SPE_ATTR_LOAD_FILTER BIT(33)
+#define SPE_ATTR_STORE_FILTER BIT(34)
+
+#define SPE_ATTR_EV_RETIRED BIT(1)
+#define SPE_ATTR_EV_CACHE BIT(3)
+#define SPE_ATTR_EV_TLB BIT(5)
+#define SPE_ATTR_EV_BRANCH BIT(7)
+
static struct perf_pmu **find_all_arm_spe_pmus(int *nr_spes, int *err)
{
struct perf_pmu **arm_spe_pmus = NULL;
@@ -108,3 +122,28 @@ struct auxtrace_record
*err = 0;
return NULL;
}
+
+void auxtrace__preprocess_evlist(struct evlist *evlist)
+{
+ struct evsel *evsel;
+ struct perf_pmu *pmu;
+
+ evlist__for_each_entry(evlist, evsel) {
+ /* Currently only supports precise_ip for branch-misses on arm64 */
+ if (!strcmp(perf_env__arch(evlist->env), "arm64")
+ && evsel->core.attr.config == PERF_COUNT_HW_BRANCH_MISSES
+ && evsel->core.attr.type == PERF_TYPE_HARDWARE
+ && evsel->core.attr.precise_ip)
+ {
+ pmu = perf_pmu__find("arm_spe_0");
+ if (pmu) {
+ evsel->pmu_name = pmu->name;
+ evsel->core.attr.type = pmu->type;
+ evsel->core.attr.config = SPE_ATTR_TS_ENABLE
+ | SPE_ATTR_BRANCH_FILTER;
+ evsel->core.attr.config1 = SPE_ATTR_EV_BRANCH;
+ evsel->core.attr.precise_ip = 0;
+ }
+ }
+ }
+}
\ No newline at end of file
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 4c301466101b..3bc61f03d572 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -2451,6 +2451,11 @@ int cmd_record(int argc, const char **argv)

argc = parse_options(argc, argv, record_options, record_usage,
PARSE_OPT_STOP_AT_NON_OPTION);
+
+ if (auxtrace__preprocess_evlist) {
+ auxtrace__preprocess_evlist(rec->evlist);
+ }
+
if (quiet)
perf_quiet_option();

diff --git a/tools/perf/util/arm-spe.c b/tools/perf/util/arm-spe.c
index 4ef22a0775a9..b21806c97dd8 100644
--- a/tools/perf/util/arm-spe.c
+++ b/tools/perf/util/arm-spe.c
@@ -778,6 +778,15 @@ arm_spe_synth_events(struct arm_spe *spe, struct perf_session *session)
attr.sample_id_all = evsel->core.attr.sample_id_all;
attr.read_format = evsel->core.attr.read_format;

+ /* If it is in the precise ip mode, there is no need to
+ * synthesize new events. */
+ if (!strncmp(evsel->name, "branch-misses", 13)) {
+ spe->sample_branch_miss = true;
+ spe->branch_miss_id = evsel->core.id[0];
+
+ return 0;
+ }
+
/* create new id val to be a fixed offset from evsel id */
id = evsel->core.id[0] + 1000000000;

diff --git a/tools/perf/util/arm-spe.h b/tools/perf/util/arm-spe.h
index 98d3235781c3..8b1fb191d03a 100644
--- a/tools/perf/util/arm-spe.h
+++ b/tools/perf/util/arm-spe.h
@@ -20,6 +20,8 @@ enum {
union perf_event;
struct perf_session;
struct perf_pmu;
+struct evlist;
+struct evsel;

struct auxtrace_record *arm_spe_recording_init(int *err,
struct perf_pmu *arm_spe_pmu);
@@ -28,4 +30,5 @@ int arm_spe_process_auxtrace_info(union perf_event *event,
struct perf_session *session);

struct perf_event_attr *arm_spe_pmu_default_config(struct perf_pmu *arm_spe_pmu);
+void arm_spe_precise_ip_support(struct evlist *evlist, struct evsel *evsel);
#endif
diff --git a/tools/perf/util/auxtrace.h b/tools/perf/util/auxtrace.h
index 52e148eea7f8..4be56bca54dc 100644
--- a/tools/perf/util/auxtrace.h
+++ b/tools/perf/util/auxtrace.h
@@ -584,6 +584,7 @@ void auxtrace__dump_auxtrace_sample(struct perf_session *session,
int auxtrace__flush_events(struct perf_session *session, struct perf_tool *tool);
void auxtrace__free_events(struct perf_session *session);
void auxtrace__free(struct perf_session *session);
+void auxtrace__preprocess_evlist(struct evlist *evlist) __attribute__((weak));

#define ITRACE_HELP \
" i: synthesize instructions events\n" \
@@ -731,6 +732,11 @@ void auxtrace__free(struct perf_session *session __maybe_unused)
{
}

+static inline
+void auxtrace__preprocess_evlist(struct evlist *evlist __maybe_unused)
+{
+}
+
static inline
int auxtrace_index__write(int fd __maybe_unused,
struct list_head *head __maybe_unused)
--
2.17.1