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 <[email protected]>
---
 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 <[email protected]>
+ *
+ * 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 <[email protected]>
+ *
+ * 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 <[email protected]>
+ *
+ * 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

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to