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-rw-r--r--tools/perf/arch/arm/util/cs-etm.c898
1 files changed, 898 insertions, 0 deletions
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 000000000..cad7bf783
--- /dev/null
+++ b/tools/perf/arch/arm/util/cs-etm.c
@@ -0,0 +1,898 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright(C) 2015 Linaro Limited. All rights reserved.
+ * Author: Mathieu Poirier <mathieu.poirier@linaro.org>
+ */
+
+#include <api/fs/fs.h>
+#include <linux/bits.h>
+#include <linux/bitops.h>
+#include <linux/compiler.h>
+#include <linux/coresight-pmu.h>
+#include <linux/kernel.h>
+#include <linux/log2.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/zalloc.h>
+
+#include "cs-etm.h"
+#include "../../util/debug.h"
+#include "../../util/record.h"
+#include "../../util/auxtrace.h"
+#include "../../util/cpumap.h"
+#include "../../util/event.h"
+#include "../../util/evlist.h"
+#include "../../util/evsel.h"
+#include "../../util/perf_api_probe.h"
+#include "../../util/evsel_config.h"
+#include "../../util/pmu.h"
+#include "../../util/cs-etm.h"
+#include <internal/lib.h> // page_size
+#include "../../util/session.h"
+
+#include <errno.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+
+struct cs_etm_recording {
+ struct auxtrace_record itr;
+ struct perf_pmu *cs_etm_pmu;
+ struct evlist *evlist;
+ int wrapped_cnt;
+ bool *wrapped;
+ bool snapshot_mode;
+ size_t snapshot_size;
+};
+
+static const char *metadata_etmv3_ro[CS_ETM_PRIV_MAX] = {
+ [CS_ETM_ETMCCER] = "mgmt/etmccer",
+ [CS_ETM_ETMIDR] = "mgmt/etmidr",
+};
+
+static const char *metadata_etmv4_ro[CS_ETMV4_PRIV_MAX] = {
+ [CS_ETMV4_TRCIDR0] = "trcidr/trcidr0",
+ [CS_ETMV4_TRCIDR1] = "trcidr/trcidr1",
+ [CS_ETMV4_TRCIDR2] = "trcidr/trcidr2",
+ [CS_ETMV4_TRCIDR8] = "trcidr/trcidr8",
+ [CS_ETMV4_TRCAUTHSTATUS] = "mgmt/trcauthstatus",
+};
+
+static bool cs_etm_is_etmv4(struct auxtrace_record *itr, int cpu);
+
+static int cs_etm_set_context_id(struct auxtrace_record *itr,
+ struct evsel *evsel, int cpu)
+{
+ struct cs_etm_recording *ptr;
+ struct perf_pmu *cs_etm_pmu;
+ char path[PATH_MAX];
+ int err = -EINVAL;
+ u32 val;
+
+ ptr = container_of(itr, struct cs_etm_recording, itr);
+ cs_etm_pmu = ptr->cs_etm_pmu;
+
+ if (!cs_etm_is_etmv4(itr, cpu))
+ goto out;
+
+ /* Get a handle on TRCIRD2 */
+ snprintf(path, PATH_MAX, "cpu%d/%s",
+ cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR2]);
+ err = perf_pmu__scan_file(cs_etm_pmu, path, "%x", &val);
+
+ /* There was a problem reading the file, bailing out */
+ if (err != 1) {
+ pr_err("%s: can't read file %s\n",
+ CORESIGHT_ETM_PMU_NAME, path);
+ goto out;
+ }
+
+ /*
+ * TRCIDR2.CIDSIZE, bit [9-5], indicates whether contextID tracing
+ * is supported:
+ * 0b00000 Context ID tracing is not supported.
+ * 0b00100 Maximum of 32-bit Context ID size.
+ * All other values are reserved.
+ */
+ val = BMVAL(val, 5, 9);
+ if (!val || val != 0x4) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ /* All good, let the kernel know */
+ evsel->core.attr.config |= (1 << ETM_OPT_CTXTID);
+ err = 0;
+
+out:
+
+ return err;
+}
+
+static int cs_etm_set_timestamp(struct auxtrace_record *itr,
+ struct evsel *evsel, int cpu)
+{
+ struct cs_etm_recording *ptr;
+ struct perf_pmu *cs_etm_pmu;
+ char path[PATH_MAX];
+ int err = -EINVAL;
+ u32 val;
+
+ ptr = container_of(itr, struct cs_etm_recording, itr);
+ cs_etm_pmu = ptr->cs_etm_pmu;
+
+ if (!cs_etm_is_etmv4(itr, cpu))
+ goto out;
+
+ /* Get a handle on TRCIRD0 */
+ snprintf(path, PATH_MAX, "cpu%d/%s",
+ cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR0]);
+ err = perf_pmu__scan_file(cs_etm_pmu, path, "%x", &val);
+
+ /* There was a problem reading the file, bailing out */
+ if (err != 1) {
+ pr_err("%s: can't read file %s\n",
+ CORESIGHT_ETM_PMU_NAME, path);
+ goto out;
+ }
+
+ /*
+ * TRCIDR0.TSSIZE, bit [28-24], indicates whether global timestamping
+ * is supported:
+ * 0b00000 Global timestamping is not implemented
+ * 0b00110 Implementation supports a maximum timestamp of 48bits.
+ * 0b01000 Implementation supports a maximum timestamp of 64bits.
+ */
+ val &= GENMASK(28, 24);
+ if (!val) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ /* All good, let the kernel know */
+ evsel->core.attr.config |= (1 << ETM_OPT_TS);
+ err = 0;
+
+out:
+ return err;
+}
+
+static int cs_etm_set_option(struct auxtrace_record *itr,
+ struct evsel *evsel, u32 option)
+{
+ int i, err = -EINVAL;
+ struct perf_cpu_map *event_cpus = evsel->evlist->core.cpus;
+ struct perf_cpu_map *online_cpus = perf_cpu_map__new(NULL);
+
+ /* Set option of each CPU we have */
+ for (i = 0; i < cpu__max_cpu(); i++) {
+ if (!cpu_map__has(event_cpus, i) ||
+ !cpu_map__has(online_cpus, i))
+ continue;
+
+ if (option & ETM_OPT_CTXTID) {
+ err = cs_etm_set_context_id(itr, evsel, i);
+ if (err)
+ goto out;
+ }
+ if (option & ETM_OPT_TS) {
+ err = cs_etm_set_timestamp(itr, evsel, i);
+ if (err)
+ goto out;
+ }
+ if (option & ~(ETM_OPT_CTXTID | ETM_OPT_TS))
+ /* Nothing else is currently supported */
+ goto out;
+ }
+
+ err = 0;
+out:
+ perf_cpu_map__put(online_cpus);
+ return err;
+}
+
+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_set_sink_attr(struct perf_pmu *pmu,
+ struct evsel *evsel)
+{
+ char msg[BUFSIZ], path[PATH_MAX], *sink;
+ struct evsel_config_term *term;
+ int ret = -EINVAL;
+ u32 hash;
+
+ if (evsel->core.attr.config2 & GENMASK(31, 0))
+ return 0;
+
+ list_for_each_entry(term, &evsel->config_terms, list) {
+ if (term->type != EVSEL__CONFIG_TERM_DRV_CFG)
+ continue;
+
+ sink = term->val.str;
+ snprintf(path, PATH_MAX, "sinks/%s", sink);
+
+ ret = perf_pmu__scan_file(pmu, path, "%x", &hash);
+ if (ret != 1) {
+ pr_err("failed to set sink \"%s\" on event %s with %d (%s)\n",
+ sink, evsel__name(evsel), errno,
+ str_error_r(errno, msg, sizeof(msg)));
+ return ret;
+ }
+
+ evsel->core.attr.config2 |= hash;
+ return 0;
+ }
+
+ /*
+ * No sink was provided on the command line - allow the CoreSight
+ * system to look for a default
+ */
+ return 0;
+}
+
+static int cs_etm_recording_options(struct auxtrace_record *itr,
+ struct evlist *evlist,
+ struct record_opts *opts)
+{
+ int ret;
+ struct cs_etm_recording *ptr =
+ container_of(itr, struct cs_etm_recording, itr);
+ struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
+ struct evsel *evsel, *cs_etm_evsel = NULL;
+ struct perf_cpu_map *cpus = evlist->core.cpus;
+ bool privileged = perf_event_paranoid_check(-1);
+ int err = 0;
+
+ ptr->evlist = evlist;
+ ptr->snapshot_mode = opts->auxtrace_snapshot_mode;
+
+ if (!record_opts__no_switch_events(opts) &&
+ perf_can_record_switch_events())
+ opts->record_switch_events = true;
+
+ evlist__for_each_entry(evlist, evsel) {
+ if (evsel->core.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->core.attr.freq = 0;
+ evsel->core.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;
+
+ ret = cs_etm_set_sink_attr(cs_etm_pmu, cs_etm_evsel);
+ if (ret)
+ return ret;
+
+ 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);
+
+ /*
+ * 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. We also need the contextID in order to be notified
+ * when a context switch happened.
+ */
+ if (!perf_cpu_map__empty(cpus)) {
+ evsel__set_sample_bit(cs_etm_evsel, CPU);
+
+ err = cs_etm_set_option(itr, cs_etm_evsel,
+ ETM_OPT_CTXTID | ETM_OPT_TS);
+ if (err)
+ goto out;
+ }
+
+ /* Add dummy event to keep tracking */
+ if (opts->full_auxtrace) {
+ struct evsel *tracking_evsel;
+
+ err = parse_events(evlist, "dummy:u", NULL);
+ if (err)
+ goto out;
+
+ tracking_evsel = evlist__last(evlist);
+ perf_evlist__set_tracking_event(evlist, tracking_evsel);
+
+ tracking_evsel->core.attr.freq = 0;
+ tracking_evsel->core.attr.sample_period = 1;
+
+ /* In per-cpu case, always need the time of mmap events etc */
+ if (!perf_cpu_map__empty(cpus))
+ evsel__set_sample_bit(tracking_evsel, TIME);
+ }
+
+out:
+ return err;
+}
+
+static u64 cs_etm_get_config(struct auxtrace_record *itr)
+{
+ u64 config = 0;
+ struct cs_etm_recording *ptr =
+ container_of(itr, struct cs_etm_recording, itr);
+ struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
+ struct evlist *evlist = ptr->evlist;
+ struct evsel *evsel;
+
+ evlist__for_each_entry(evlist, evsel) {
+ if (evsel->core.attr.type == cs_etm_pmu->type) {
+ /*
+ * Variable perf_event_attr::config is assigned to
+ * ETMv3/PTM. The bit fields have been made to match
+ * the ETMv3.5 ETRMCR register specification. See the
+ * PMU_FORMAT_ATTR() declarations in
+ * drivers/hwtracing/coresight/coresight-perf.c for
+ * details.
+ */
+ config = evsel->core.attr.config;
+ break;
+ }
+ }
+
+ return config;
+}
+
+#ifndef BIT
+#define BIT(N) (1UL << (N))
+#endif
+
+static u64 cs_etmv4_get_config(struct auxtrace_record *itr)
+{
+ u64 config = 0;
+ u64 config_opts = 0;
+
+ /*
+ * The perf event variable config bits represent both
+ * the command line options and register programming
+ * bits in ETMv3/PTM. For ETMv4 we must remap options
+ * to real bits
+ */
+ config_opts = cs_etm_get_config(itr);
+ if (config_opts & BIT(ETM_OPT_CYCACC))
+ config |= BIT(ETM4_CFG_BIT_CYCACC);
+ if (config_opts & BIT(ETM_OPT_CTXTID))
+ config |= BIT(ETM4_CFG_BIT_CTXTID);
+ if (config_opts & BIT(ETM_OPT_TS))
+ config |= BIT(ETM4_CFG_BIT_TS);
+ if (config_opts & BIT(ETM_OPT_RETSTK))
+ config |= BIT(ETM4_CFG_BIT_RETSTK);
+
+ return config;
+}
+
+static size_t
+cs_etm_info_priv_size(struct auxtrace_record *itr __maybe_unused,
+ struct evlist *evlist __maybe_unused)
+{
+ int i;
+ int etmv3 = 0, etmv4 = 0;
+ struct perf_cpu_map *event_cpus = evlist->core.cpus;
+ struct perf_cpu_map *online_cpus = perf_cpu_map__new(NULL);
+
+ /* cpu map is not empty, we have specific CPUs to work with */
+ if (!perf_cpu_map__empty(event_cpus)) {
+ for (i = 0; i < cpu__max_cpu(); i++) {
+ if (!cpu_map__has(event_cpus, i) ||
+ !cpu_map__has(online_cpus, i))
+ continue;
+
+ if (cs_etm_is_etmv4(itr, i))
+ etmv4++;
+ else
+ etmv3++;
+ }
+ } else {
+ /* get configuration for all CPUs in the system */
+ for (i = 0; i < cpu__max_cpu(); i++) {
+ if (!cpu_map__has(online_cpus, i))
+ continue;
+
+ if (cs_etm_is_etmv4(itr, i))
+ etmv4++;
+ else
+ etmv3++;
+ }
+ }
+
+ perf_cpu_map__put(online_cpus);
+
+ return (CS_ETM_HEADER_SIZE +
+ (etmv4 * CS_ETMV4_PRIV_SIZE) +
+ (etmv3 * CS_ETMV3_PRIV_SIZE));
+}
+
+static bool cs_etm_is_etmv4(struct auxtrace_record *itr, int cpu)
+{
+ bool ret = false;
+ char path[PATH_MAX];
+ int scan;
+ unsigned int val;
+ struct cs_etm_recording *ptr =
+ container_of(itr, struct cs_etm_recording, itr);
+ struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
+
+ /* Take any of the RO files for ETMv4 and see if it present */
+ snprintf(path, PATH_MAX, "cpu%d/%s",
+ cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR0]);
+ scan = perf_pmu__scan_file(cs_etm_pmu, path, "%x", &val);
+
+ /* The file was read successfully, we have a winner */
+ if (scan == 1)
+ ret = true;
+
+ return ret;
+}
+
+static int cs_etm_get_ro(struct perf_pmu *pmu, int cpu, const char *path)
+{
+ char pmu_path[PATH_MAX];
+ int scan;
+ unsigned int val = 0;
+
+ /* Get RO metadata from sysfs */
+ snprintf(pmu_path, PATH_MAX, "cpu%d/%s", cpu, path);
+
+ scan = perf_pmu__scan_file(pmu, pmu_path, "%x", &val);
+ if (scan != 1)
+ pr_err("%s: error reading: %s\n", __func__, pmu_path);
+
+ return val;
+}
+
+static void cs_etm_get_metadata(int cpu, u32 *offset,
+ struct auxtrace_record *itr,
+ struct perf_record_auxtrace_info *info)
+{
+ u32 increment;
+ u64 magic;
+ struct cs_etm_recording *ptr =
+ container_of(itr, struct cs_etm_recording, itr);
+ struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
+
+ /* first see what kind of tracer this cpu is affined to */
+ if (cs_etm_is_etmv4(itr, cpu)) {
+ magic = __perf_cs_etmv4_magic;
+ /* Get trace configuration register */
+ info->priv[*offset + CS_ETMV4_TRCCONFIGR] =
+ cs_etmv4_get_config(itr);
+ /* Get traceID from the framework */
+ info->priv[*offset + CS_ETMV4_TRCTRACEIDR] =
+ coresight_get_trace_id(cpu);
+ /* Get read-only information from sysFS */
+ info->priv[*offset + CS_ETMV4_TRCIDR0] =
+ cs_etm_get_ro(cs_etm_pmu, cpu,
+ metadata_etmv4_ro[CS_ETMV4_TRCIDR0]);
+ info->priv[*offset + CS_ETMV4_TRCIDR1] =
+ cs_etm_get_ro(cs_etm_pmu, cpu,
+ metadata_etmv4_ro[CS_ETMV4_TRCIDR1]);
+ info->priv[*offset + CS_ETMV4_TRCIDR2] =
+ cs_etm_get_ro(cs_etm_pmu, cpu,
+ metadata_etmv4_ro[CS_ETMV4_TRCIDR2]);
+ info->priv[*offset + CS_ETMV4_TRCIDR8] =
+ cs_etm_get_ro(cs_etm_pmu, cpu,
+ metadata_etmv4_ro[CS_ETMV4_TRCIDR8]);
+ info->priv[*offset + CS_ETMV4_TRCAUTHSTATUS] =
+ cs_etm_get_ro(cs_etm_pmu, cpu,
+ metadata_etmv4_ro
+ [CS_ETMV4_TRCAUTHSTATUS]);
+
+ /* How much space was used */
+ increment = CS_ETMV4_PRIV_MAX;
+ } else {
+ magic = __perf_cs_etmv3_magic;
+ /* Get configuration register */
+ info->priv[*offset + CS_ETM_ETMCR] = cs_etm_get_config(itr);
+ /* Get traceID from the framework */
+ info->priv[*offset + CS_ETM_ETMTRACEIDR] =
+ coresight_get_trace_id(cpu);
+ /* Get read-only information from sysFS */
+ info->priv[*offset + CS_ETM_ETMCCER] =
+ cs_etm_get_ro(cs_etm_pmu, cpu,
+ metadata_etmv3_ro[CS_ETM_ETMCCER]);
+ info->priv[*offset + CS_ETM_ETMIDR] =
+ cs_etm_get_ro(cs_etm_pmu, cpu,
+ metadata_etmv3_ro[CS_ETM_ETMIDR]);
+
+ /* How much space was used */
+ increment = CS_ETM_PRIV_MAX;
+ }
+
+ /* Build generic header portion */
+ info->priv[*offset + CS_ETM_MAGIC] = magic;
+ info->priv[*offset + CS_ETM_CPU] = cpu;
+ /* Where the next CPU entry should start from */
+ *offset += increment;
+}
+
+static int cs_etm_info_fill(struct auxtrace_record *itr,
+ struct perf_session *session,
+ struct perf_record_auxtrace_info *info,
+ size_t priv_size)
+{
+ int i;
+ u32 offset;
+ u64 nr_cpu, type;
+ struct perf_cpu_map *cpu_map;
+ struct perf_cpu_map *event_cpus = session->evlist->core.cpus;
+ struct perf_cpu_map *online_cpus = perf_cpu_map__new(NULL);
+ struct cs_etm_recording *ptr =
+ container_of(itr, struct cs_etm_recording, itr);
+ struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
+
+ if (priv_size != cs_etm_info_priv_size(itr, session->evlist))
+ return -EINVAL;
+
+ if (!session->evlist->core.nr_mmaps)
+ return -EINVAL;
+
+ /* If the cpu_map is empty all online CPUs are involved */
+ if (perf_cpu_map__empty(event_cpus)) {
+ cpu_map = online_cpus;
+ } else {
+ /* Make sure all specified CPUs are online */
+ for (i = 0; i < perf_cpu_map__nr(event_cpus); i++) {
+ if (cpu_map__has(event_cpus, i) &&
+ !cpu_map__has(online_cpus, i))
+ return -EINVAL;
+ }
+
+ cpu_map = event_cpus;
+ }
+
+ nr_cpu = perf_cpu_map__nr(cpu_map);
+ /* Get PMU type as dynamically assigned by the core */
+ type = cs_etm_pmu->type;
+
+ /* First fill out the session header */
+ info->type = PERF_AUXTRACE_CS_ETM;
+ info->priv[CS_HEADER_VERSION_0] = 0;
+ info->priv[CS_PMU_TYPE_CPUS] = type << 32;
+ info->priv[CS_PMU_TYPE_CPUS] |= nr_cpu;
+ info->priv[CS_ETM_SNAPSHOT] = ptr->snapshot_mode;
+
+ offset = CS_ETM_SNAPSHOT + 1;
+
+ for (i = 0; i < cpu__max_cpu() && offset < priv_size; i++)
+ if (cpu_map__has(cpu_map, i))
+ cs_etm_get_metadata(i, &offset, itr, info);
+
+ perf_cpu_map__put(online_cpus);
+
+ return 0;
+}
+
+static int cs_etm_alloc_wrapped_array(struct cs_etm_recording *ptr, int idx)
+{
+ bool *wrapped;
+ int cnt = ptr->wrapped_cnt;
+
+ /* Make @ptr->wrapped as big as @idx */
+ while (cnt <= idx)
+ cnt++;
+
+ /*
+ * Free'ed in cs_etm_recording_free(). Using realloc() to avoid
+ * cross compilation problems where the host's system supports
+ * reallocarray() but not the target.
+ */
+ wrapped = realloc(ptr->wrapped, cnt * sizeof(bool));
+ if (!wrapped)
+ return -ENOMEM;
+
+ wrapped[cnt - 1] = false;
+ ptr->wrapped_cnt = cnt;
+ ptr->wrapped = wrapped;
+
+ return 0;
+}
+
+static bool cs_etm_buffer_has_wrapped(unsigned char *buffer,
+ size_t buffer_size, u64 head)
+{
+ u64 i, watermark;
+ u64 *buf = (u64 *)buffer;
+ size_t buf_size = buffer_size;
+
+ /*
+ * We want to look the very last 512 byte (chosen arbitrarily) in
+ * the ring buffer.
+ */
+ watermark = buf_size - 512;
+
+ /*
+ * @head is continuously increasing - if its value is equal or greater
+ * than the size of the ring buffer, it has wrapped around.
+ */
+ if (head >= buffer_size)
+ return true;
+
+ /*
+ * The value of @head is somewhere within the size of the ring buffer.
+ * This can be that there hasn't been enough data to fill the ring
+ * buffer yet or the trace time was so long that @head has numerically
+ * wrapped around. To find we need to check if we have data at the very
+ * end of the ring buffer. We can reliably do this because mmap'ed
+ * pages are zeroed out and there is a fresh mapping with every new
+ * session.
+ */
+
+ /* @head is less than 512 byte from the end of the ring buffer */
+ if (head > watermark)
+ watermark = head;
+
+ /*
+ * Speed things up by using 64 bit transactions (see "u64 *buf" above)
+ */
+ watermark >>= 3;
+ buf_size >>= 3;
+
+ /*
+ * If we find trace data at the end of the ring buffer, @head has
+ * been there and has numerically wrapped around at least once.
+ */
+ for (i = watermark; i < buf_size; i++)
+ if (buf[i])
+ return true;
+
+ return false;
+}
+
+static int cs_etm_find_snapshot(struct auxtrace_record *itr,
+ int idx, struct auxtrace_mmap *mm,
+ unsigned char *data,
+ u64 *head, u64 *old)
+{
+ int err;
+ bool wrapped;
+ struct cs_etm_recording *ptr =
+ container_of(itr, struct cs_etm_recording, itr);
+
+ /*
+ * Allocate memory to keep track of wrapping if this is the first
+ * time we deal with this *mm.
+ */
+ if (idx >= ptr->wrapped_cnt) {
+ err = cs_etm_alloc_wrapped_array(ptr, idx);
+ if (err)
+ return err;
+ }
+
+ /*
+ * Check to see if *head has wrapped around. If it hasn't only the
+ * amount of data between *head and *old is snapshot'ed to avoid
+ * bloating the perf.data file with zeros. But as soon as *head has
+ * wrapped around the entire size of the AUX ring buffer it taken.
+ */
+ wrapped = ptr->wrapped[idx];
+ if (!wrapped && cs_etm_buffer_has_wrapped(data, mm->len, *head)) {
+ wrapped = true;
+ ptr->wrapped[idx] = true;
+ }
+
+ 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);
+
+ /* No wrap has occurred, we can just use *head and *old. */
+ if (!wrapped)
+ return 0;
+
+ /*
+ * *head has wrapped around - adjust *head and *old to pickup the
+ * entire content of the AUX buffer.
+ */
+ if (*head >= mm->len) {
+ *old = *head - mm->len;
+ } else {
+ *head += mm->len;
+ *old = *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 evsel *evsel;
+
+ evlist__for_each_entry(ptr->evlist, evsel) {
+ if (evsel->core.attr.type == ptr->cs_etm_pmu->type)
+ return evsel__disable(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 evsel *evsel;
+
+ evlist__for_each_entry(ptr->evlist, evsel) {
+ if (evsel->core.attr.type == ptr->cs_etm_pmu->type)
+ return evsel__enable(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);
+
+ zfree(&ptr->wrapped);
+ free(ptr);
+}
+
+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.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 = auxtrace_record__read_finish;
+
+ *err = 0;
+ return &ptr->itr;
+out:
+ return NULL;
+}