[PATCH V2 30/30] perf tools: adding coresight etm PMU record capabilities
From: Mathieu Poirier
Date: Sun Oct 18 2015 - 14:27:06 EST
Coresight ETMs are IP blocks allowing to perform HW assisted tracing
on a CPU core. This patch introduce the required auxiliary API
functions allowing the perf core to interact with a tracer.
Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
---
tools/perf/arch/arm/util/Build | 2 +-
tools/perf/arch/arm/util/auxtrace.c | 48 ++++
tools/perf/arch/arm/util/cs_etm.c | 444 ++++++++++++++++++++++++++++++++++++
tools/perf/arch/arm/util/cs_etm.h | 37 +++
4 files changed, 530 insertions(+), 1 deletion(-)
create mode 100644 tools/perf/arch/arm/util/auxtrace.c
create mode 100644 tools/perf/arch/arm/util/cs_etm.c
create mode 100644 tools/perf/arch/arm/util/cs_etm.h
diff --git a/tools/perf/arch/arm/util/Build b/tools/perf/arch/arm/util/Build
index 371a3bf12297..87545604b029 100644
--- a/tools/perf/arch/arm/util/Build
+++ b/tools/perf/arch/arm/util/Build
@@ -3,4 +3,4 @@ libperf-$(CONFIG_DWARF) += dwarf-regs.o
libperf-$(CONFIG_LIBUNWIND) += unwind-libunwind.o
libperf-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
-libperf-$(CONFIG_AUXTRACE_ARM) += pmu.o
+libperf-$(CONFIG_AUXTRACE_ARM) += pmu.o auxtrace.o cs_etm.o
diff --git a/tools/perf/arch/arm/util/auxtrace.c b/tools/perf/arch/arm/util/auxtrace.c
new file mode 100644
index 000000000000..4988fdf7cb8a
--- /dev/null
+++ b/tools/perf/arch/arm/util/auxtrace.c
@@ -0,0 +1,48 @@
+/*
+ * Copyright(C) 2015 Linaro Limited. All rights reserved.
+ * Author: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdbool.h>
+#include <linux/coresight-pmu.h>
+
+#include "../../util/auxtrace.h"
+#include "../../util/evlist.h"
+#include "../../util/pmu.h"
+#include "cs_etm.h"
+
+struct auxtrace_record
+*auxtrace_record__init(struct perf_evlist *evlist, int *err)
+{
+ struct perf_pmu *cs_etm_pmu;
+ struct perf_evsel *evsel;
+ bool found_etm = false;
+
+ cs_etm_pmu = perf_pmu__find(CORESIGHT_ETM_PMU_NAME);
+
+ if (evlist) {
+ evlist__for_each(evlist, evsel) {
+ if (cs_etm_pmu &&
+ evsel->attr.type == cs_etm_pmu->type)
+ found_etm = true;
+ }
+ }
+
+ if (found_etm)
+ return cs_etm_record_init(err);
+
+ *err = -EINVAL;
+ return NULL;
+}
diff --git a/tools/perf/arch/arm/util/cs_etm.c b/tools/perf/arch/arm/util/cs_etm.c
new file mode 100644
index 000000000000..2e89b44dd4da
--- /dev/null
+++ b/tools/perf/arch/arm/util/cs_etm.c
@@ -0,0 +1,444 @@
+/*
+ * Copyright(C) 2015 Linaro Limited. All rights reserved.
+ * Author: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <api/fs/fs.h>
+#include <linux/bitops.h>
+#include <linux/coresight-pmu.h>
+#include <linux/kernel.h>
+#include <linux/log2.h>
+#include <linux/types.h>
+
+#include "../../perf.h"
+#include "../../util/auxtrace.h"
+#include "../../util/cpumap.h"
+#include "../../util/evlist.h"
+#include "../../util/pmu.h"
+#include "../../util/thread_map.h"
+#include "cs_etm.h"
+
+#include <stdlib.h>
+
+/* Also used by Intel - should go to a common header */
+#define KiB(x) ((x) * 1024)
+#define MiB(x) ((x) * 1024 * 1024)
+
+struct cs_etm_recording {
+ struct auxtrace_record itr;
+ struct perf_pmu *cs_etm_pmu;
+ struct perf_evlist *evlist;
+ bool snapshot_mode;
+ size_t snapshot_size;
+};
+
+static int cs_etm_parse_snapshot_options(struct auxtrace_record *itr,
+ struct record_opts *opts,
+ const char *str)
+{
+ struct cs_etm_recording *ptr =
+ container_of(itr, struct cs_etm_recording, itr);
+ unsigned long long snapshot_size = 0;
+ char *endptr;
+
+ if (str) {
+ snapshot_size = strtoull(str, &endptr, 0);
+ if (*endptr || snapshot_size > SIZE_MAX)
+ return -1;
+ }
+
+ opts->auxtrace_snapshot_mode = true;
+ opts->auxtrace_snapshot_size = snapshot_size;
+ ptr->snapshot_size = snapshot_size;
+
+ return 0;
+}
+
+static int cs_etm_recording_options(struct auxtrace_record *itr,
+ struct perf_evlist *evlist,
+ struct record_opts *opts)
+{
+ struct cs_etm_recording *ptr =
+ container_of(itr, struct cs_etm_recording, itr);
+ struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
+ struct perf_evsel *evsel, *cs_etm_evsel = NULL;
+ const struct cpu_map *cpus = evlist->cpus;
+ bool privileged = (geteuid() == 0 || perf_event_paranoid() < 0);
+
+ ptr->evlist = evlist;
+ ptr->snapshot_mode = opts->auxtrace_snapshot_mode;
+
+ evlist__for_each(evlist, evsel) {
+ if (evsel->attr.type == cs_etm_pmu->type) {
+ if (cs_etm_evsel) {
+ pr_err("There may be only one %s event\n",
+ CORESIGHT_ETM_PMU_NAME);
+ return -EINVAL;
+ }
+ evsel->attr.freq = 0;
+ evsel->attr.sample_period = 1;
+ cs_etm_evsel = evsel;
+ opts->full_auxtrace = true;
+ }
+ }
+
+ /* no need to continue if at least one event of interest was found */
+ if (!cs_etm_evsel)
+ return 0;
+
+ if (opts->use_clockid) {
+ pr_err("Cannot use clockid (-k option) with %s\n",
+ CORESIGHT_ETM_PMU_NAME);
+ return -EINVAL;
+ }
+
+ /* we are in snapshot mode */
+ if (opts->auxtrace_snapshot_mode) {
+ /*
+ * No size were given to '-S' or '-m,', so go with
+ * the default
+ */
+ if (!opts->auxtrace_snapshot_size &&
+ !opts->auxtrace_mmap_pages) {
+ if (privileged) {
+ opts->auxtrace_mmap_pages = MiB(4) / page_size;
+ } else {
+ opts->auxtrace_mmap_pages =
+ KiB(128) / page_size;
+ if (opts->mmap_pages == UINT_MAX)
+ opts->mmap_pages = KiB(256) / page_size;
+ }
+ } else if (!opts->auxtrace_mmap_pages && !privileged &&
+ opts->mmap_pages == UINT_MAX) {
+ opts->mmap_pages = KiB(256) / page_size;
+ }
+
+ /*
+ * '-m,xyz' was specified but no snapshot size, so make the
+ * snapshot size as big as the auxtrace mmap area.
+ */
+ if (!opts->auxtrace_snapshot_size) {
+ opts->auxtrace_snapshot_size =
+ opts->auxtrace_mmap_pages * (size_t)page_size;
+ }
+
+ /*
+ * -Sxyz was specified but no auxtrace mmap area, so make the
+ * auxtrace mmap area big enough to fit the requested snapshot
+ * size.
+ */
+ if (!opts->auxtrace_mmap_pages) {
+ size_t sz = opts->auxtrace_snapshot_size;
+
+ sz = round_up(sz, page_size) / page_size;
+ opts->auxtrace_mmap_pages = roundup_pow_of_two(sz);
+ }
+
+ /* Snapshost size can't be bigger than the auxtrace area */
+ if (opts->auxtrace_snapshot_size >
+ opts->auxtrace_mmap_pages * (size_t)page_size) {
+ pr_err("Snapshot size %zu must not be greater than AUX area tracing mmap size %zu\n",
+ opts->auxtrace_snapshot_size,
+ opts->auxtrace_mmap_pages * (size_t)page_size);
+ return -EINVAL;
+ }
+
+ /* Something went wrong somewhere - this shouldn't happen */
+ if (!opts->auxtrace_snapshot_size ||
+ !opts->auxtrace_mmap_pages) {
+ pr_err("Failed to calculate default snapshot size and/or AUX area tracing mmap pages\n");
+ return -EINVAL;
+ }
+ }
+
+ /* We are in full trace mode but '-m,xyz' wasn't specified */
+ if (opts->full_auxtrace && !opts->auxtrace_mmap_pages) {
+ if (privileged) {
+ opts->auxtrace_mmap_pages = MiB(4) / page_size;
+ } else {
+ opts->auxtrace_mmap_pages = KiB(128) / page_size;
+ if (opts->mmap_pages == UINT_MAX)
+ opts->mmap_pages = KiB(256) / page_size;
+ }
+
+ }
+
+ /* Validate auxtrace_mmap_pages provided by user */
+ if (opts->auxtrace_mmap_pages) {
+ unsigned int max_page = (KiB(128) / page_size);
+ size_t sz = opts->auxtrace_mmap_pages * (size_t)page_size;
+
+ if (!privileged &&
+ opts->auxtrace_mmap_pages > max_page) {
+ opts->auxtrace_mmap_pages = max_page;
+ pr_err("auxtrace too big, truncating to %d\n",
+ max_page);
+ }
+
+ if (!is_power_of_2(sz)) {
+ pr_err("Invalid mmap size for %s: must be a power of 2\n",
+ CORESIGHT_ETM_PMU_NAME);
+ return -EINVAL;
+ }
+ }
+
+ if (opts->auxtrace_snapshot_mode)
+ pr_debug2("%s snapshot size: %zu\n", CORESIGHT_ETM_PMU_NAME,
+ opts->auxtrace_snapshot_size);
+
+ if (cs_etm_evsel) {
+ /*
+ * To obtain the auxtrace buffer file descriptor, the auxtrace
+ * event must come first.
+ */
+ perf_evlist__to_front(evlist, cs_etm_evsel);
+ /*
+ * In the case of per-cpu mmaps, we need the CPU on the
+ * AUX event.
+ */
+ if (!cpu_map__empty(cpus))
+ perf_evsel__set_sample_bit(cs_etm_evsel, CPU);
+ }
+
+ /* Add dummy event to keep tracking */
+ if (opts->full_auxtrace) {
+ struct perf_evsel *tracking_evsel;
+ int err;
+
+ err = parse_events(evlist, "dummy:u", NULL);
+ if (err)
+ return err;
+
+ tracking_evsel = perf_evlist__last(evlist);
+ perf_evlist__set_tracking_event(evlist, tracking_evsel);
+
+ tracking_evsel->attr.freq = 0;
+ tracking_evsel->attr.sample_period = 1;
+
+ /* In per-cpu case, always need the time of mmap events etc */
+ if (!cpu_map__empty(cpus))
+ perf_evsel__set_sample_bit(tracking_evsel, TIME);
+ }
+
+ return 0;
+}
+
+static size_t
+cs_etm_info_priv_size(struct auxtrace_record *itr __maybe_unused,
+ struct perf_session *session __maybe_unused)
+{
+ int records;
+ const struct cpu_map *cpus = session->evlist->cpus;
+
+ if (!cpu_map__empty(cpus)) {
+ records = cpu_map__nr(cpus);
+ goto out;
+ }
+
+ set_max_cpu_num();
+ records = cpu__max_cpu();
+out:
+ return records * CS_ETM_PRIV_SIZE;
+}
+
+static const char *metadata[CS_ETM_PRIV_MAX] = {
+ [CS_ETM_ETMCR] = "etmcr",
+ [CS_ETM_ETMCCER] = "etmccer",
+ [CS_ETM_ETMIDR] = "etmidr",
+ [CS_ETM_ETMTRACEIDR] = "etmtraceidr",
+};
+
+static int cs_etm_get_metadata(int cpu, int offset,
+ struct cs_etm_recording *ptr,
+ struct auxtrace_info_event *info)
+{
+ int i, ret = 0;
+ const char *sysfs = sysfs__mountpoint();
+
+ if (!sysfs)
+ return -EINVAL;
+
+ info->priv[offset + CS_ETM_MAGIC] = __perf_cs_etm_magic;
+ info->priv[offset + CS_ETM_CPU] = cpu;
+ info->priv[offset + CS_ETM_SNAPSHOT] = ptr->snapshot_mode;
+
+ /* get metadata from sysfs */
+ for (i = CS_ETM_ETMCR; i < CS_ETM_PRIV_MAX && !ret; i++) {
+ FILE *file;
+ char path[PATH_MAX], value[128];
+
+ snprintf(path, PATH_MAX,
+ "%s" EVENT_SOURCE_DEVICE_PATH "%s/cpu%d/mgmt/%s",
+ sysfs, CORESIGHT_ETM_PMU_NAME, cpu, metadata[i]);
+
+ file = fopen(path, "r");
+ if (!file)
+ return -EINVAL;
+
+ if (fscanf(file, "%s", value) != 1)
+ ret = -EINVAL;
+
+ fclose(file);
+
+ info->priv[offset + i] = strtol(value, NULL, 16);
+ }
+
+ return 0;
+}
+
+static int cs_etm_info_fill(struct auxtrace_record *itr,
+ struct perf_session *session,
+ struct auxtrace_info_event *auxtrace_info,
+ size_t priv_size)
+{
+ int i, nr_cpu, ret = 0;
+ const struct cpu_map *cpus = session->evlist->cpus;
+ struct cs_etm_recording *ptr =
+ container_of(itr, struct cs_etm_recording, itr);
+
+ if (priv_size != cs_etm_info_priv_size(itr, session))
+ return -EINVAL;
+
+ if (!session->evlist->nr_mmaps)
+ return -EINVAL;
+
+ auxtrace_info->type = PERF_AUXTRACE_CS_ETM;
+
+ /* cpu map is not empty, we have specific CPUs to work with */
+ if (!cpu_map__empty(cpus)) {
+ for (i = 0; i < cpu_map__nr(cpus); i++)
+ ret = cs_etm_get_metadata(cpus->map[i],
+ i * CS_ETM_PRIV_MAX,
+ ptr, auxtrace_info);
+ if (ret)
+ goto out;
+ }
+
+ /* get configuration for all CPUs in the system */
+ nr_cpu = cpu__max_cpu();
+ for (i = 0; i < nr_cpu; i++) {
+ ret = cs_etm_get_metadata(i, i * CS_ETM_PRIV_MAX,
+ ptr, auxtrace_info);
+ if (ret)
+ goto out;
+ }
+
+out:
+ return ret;
+}
+
+static int cs_etm_find_snapshot(struct auxtrace_record *itr __maybe_unused,
+ int idx, struct auxtrace_mmap *mm,
+ unsigned char *data __maybe_unused,
+ u64 *head, u64 *old)
+{
+ pr_debug3("%s: mmap index %d old head %zu new head %zu size %zu\n",
+ __func__, idx, (size_t)*old, (size_t)*head, mm->len);
+
+ *old = *head;
+ *head += mm->len;
+
+ return 0;
+}
+
+static int cs_etm_snapshot_start(struct auxtrace_record *itr)
+{
+ struct cs_etm_recording *ptr =
+ container_of(itr, struct cs_etm_recording, itr);
+ struct perf_evsel *evsel;
+
+ evlist__for_each(ptr->evlist, evsel) {
+ if (evsel->attr.type == ptr->cs_etm_pmu->type)
+ return perf_evlist__disable_event(ptr->evlist, evsel);
+ }
+ return -EINVAL;
+}
+
+static int cs_etm_snapshot_finish(struct auxtrace_record *itr)
+{
+ struct cs_etm_recording *ptr =
+ container_of(itr, struct cs_etm_recording, itr);
+ struct perf_evsel *evsel;
+
+ evlist__for_each(ptr->evlist, evsel) {
+ if (evsel->attr.type == ptr->cs_etm_pmu->type)
+ return perf_evlist__enable_event(ptr->evlist, evsel);
+ }
+ return -EINVAL;
+}
+
+static u64 cs_etm_reference(struct auxtrace_record *itr __maybe_unused)
+{
+ return (((u64) rand() << 0) & 0x00000000FFFFFFFFull) |
+ (((u64) rand() << 32) & 0xFFFFFFFF00000000ull);
+}
+
+static void cs_etm_recording_free(struct auxtrace_record *itr)
+{
+ struct cs_etm_recording *ptr =
+ container_of(itr, struct cs_etm_recording, itr);
+ free(ptr);
+}
+
+static int cs_etm_read_finish(struct auxtrace_record *itr, int idx)
+{
+ struct cs_etm_recording *ptr =
+ container_of(itr, struct cs_etm_recording, itr);
+ struct perf_evsel *evsel;
+
+ evlist__for_each(ptr->evlist, evsel) {
+ if (evsel->attr.type == ptr->cs_etm_pmu->type)
+ return perf_evlist__enable_event_idx(ptr->evlist,
+ evsel, idx);
+ }
+
+ return -EINVAL;
+}
+
+struct auxtrace_record *cs_etm_record_init(int *err)
+{
+ struct perf_pmu *cs_etm_pmu;
+ struct cs_etm_recording *ptr;
+
+ cs_etm_pmu = perf_pmu__find(CORESIGHT_ETM_PMU_NAME);
+
+ if (!cs_etm_pmu) {
+ *err = -EINVAL;
+ goto out;
+ }
+
+ ptr = zalloc(sizeof(struct cs_etm_recording));
+ if (!ptr) {
+ *err = -ENOMEM;
+ goto out;
+ }
+
+ ptr->cs_etm_pmu = cs_etm_pmu;
+ ptr->itr.parse_snapshot_options = cs_etm_parse_snapshot_options;
+ ptr->itr.recording_options = cs_etm_recording_options;
+ ptr->itr.info_priv_size = cs_etm_info_priv_size;
+ ptr->itr.info_fill = cs_etm_info_fill;
+ ptr->itr.find_snapshot = cs_etm_find_snapshot;
+ ptr->itr.snapshot_start = cs_etm_snapshot_start;
+ ptr->itr.snapshot_finish = cs_etm_snapshot_finish;
+ ptr->itr.reference = cs_etm_reference;
+ ptr->itr.free = cs_etm_recording_free;
+ ptr->itr.read_finish = cs_etm_read_finish;
+
+ *err = 0;
+ return &ptr->itr;
+out:
+ return NULL;
+}
diff --git a/tools/perf/arch/arm/util/cs_etm.h b/tools/perf/arch/arm/util/cs_etm.h
new file mode 100644
index 000000000000..b3b3f16d80e3
--- /dev/null
+++ b/tools/perf/arch/arm/util/cs_etm.h
@@ -0,0 +1,37 @@
+/*
+ * Copyright(C) 2015 Linaro Limited. All rights reserved.
+ * Author: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef INCLUDE__PERF_CS_ETM_H__
+#define INCLUDE__PERF_CS_ETM_H__
+
+enum {
+ CS_ETM_MAGIC,
+ CS_ETM_CPU,
+ CS_ETM_SNAPSHOT,
+ CS_ETM_ETMCR,
+ CS_ETM_ETMCCER,
+ CS_ETM_ETMIDR,
+ CS_ETM_ETMTRACEIDR,
+ CS_ETM_PRIV_MAX,
+};
+
+static const u64 __perf_cs_etm_magic = 0x3030303030303030ULL;
+#define CS_ETM_PRIV_SIZE (CS_ETM_PRIV_MAX * sizeof(u64))
+
+struct auxtrace_record *cs_etm_record_init(int *err);
+
+#endif
--
1.9.1
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