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-rw-r--r--tools/perf/arch/arm64/util/arm-spe.c545
1 files changed, 545 insertions, 0 deletions
diff --git a/tools/perf/arch/arm64/util/arm-spe.c b/tools/perf/arch/arm64/util/arm-spe.c
new file mode 100644
index 000000000..d4c234076
--- /dev/null
+++ b/tools/perf/arch/arm64/util/arm-spe.c
@@ -0,0 +1,545 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Arm Statistical Profiling Extensions (SPE) support
+ * Copyright (c) 2017-2018, Arm Ltd.
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/bitops.h>
+#include <linux/log2.h>
+#include <linux/zalloc.h>
+#include <time.h>
+
+#include "../../../util/cpumap.h"
+#include "../../../util/event.h"
+#include "../../../util/evsel.h"
+#include "../../../util/evsel_config.h"
+#include "../../../util/evlist.h"
+#include "../../../util/session.h"
+#include <internal/lib.h> // page_size
+#include "../../../util/pmu.h"
+#include "../../../util/debug.h"
+#include "../../../util/auxtrace.h"
+#include "../../../util/record.h"
+#include "../../../util/arm-spe.h"
+#include <tools/libc_compat.h> // reallocarray
+
+#define KiB(x) ((x) * 1024)
+#define MiB(x) ((x) * 1024 * 1024)
+
+struct arm_spe_recording {
+ struct auxtrace_record itr;
+ struct perf_pmu *arm_spe_pmu;
+ struct evlist *evlist;
+ int wrapped_cnt;
+ bool *wrapped;
+};
+
+static void arm_spe_set_timestamp(struct auxtrace_record *itr,
+ struct evsel *evsel)
+{
+ struct arm_spe_recording *ptr;
+ struct perf_pmu *arm_spe_pmu;
+ struct evsel_config_term *term = evsel__get_config_term(evsel, CFG_CHG);
+ u64 user_bits = 0, bit;
+
+ ptr = container_of(itr, struct arm_spe_recording, itr);
+ arm_spe_pmu = ptr->arm_spe_pmu;
+
+ if (term)
+ user_bits = term->val.cfg_chg;
+
+ bit = perf_pmu__format_bits(&arm_spe_pmu->format, "ts_enable");
+
+ /* Skip if user has set it */
+ if (bit & user_bits)
+ return;
+
+ evsel->core.attr.config |= bit;
+}
+
+static size_t
+arm_spe_info_priv_size(struct auxtrace_record *itr __maybe_unused,
+ struct evlist *evlist __maybe_unused)
+{
+ return ARM_SPE_AUXTRACE_PRIV_SIZE;
+}
+
+static int arm_spe_info_fill(struct auxtrace_record *itr,
+ struct perf_session *session,
+ struct perf_record_auxtrace_info *auxtrace_info,
+ size_t priv_size)
+{
+ struct arm_spe_recording *sper =
+ container_of(itr, struct arm_spe_recording, itr);
+ struct perf_pmu *arm_spe_pmu = sper->arm_spe_pmu;
+
+ if (priv_size != ARM_SPE_AUXTRACE_PRIV_SIZE)
+ return -EINVAL;
+
+ if (!session->evlist->core.nr_mmaps)
+ return -EINVAL;
+
+ auxtrace_info->type = PERF_AUXTRACE_ARM_SPE;
+ auxtrace_info->priv[ARM_SPE_PMU_TYPE] = arm_spe_pmu->type;
+
+ return 0;
+}
+
+static void
+arm_spe_snapshot_resolve_auxtrace_defaults(struct record_opts *opts,
+ bool privileged)
+{
+ /*
+ * The default snapshot size is the auxtrace mmap size. If neither auxtrace mmap size nor
+ * snapshot size is specified, then the default is 4MiB for privileged users, 128KiB for
+ * unprivileged users.
+ *
+ * The default auxtrace mmap size is 4MiB/page_size for privileged users, 128KiB for
+ * unprivileged users. If an unprivileged user does not specify mmap pages, the mmap pages
+ * will be reduced from the default 512KiB/page_size to 256KiB/page_size, otherwise the
+ * user is likely to get an error as they exceed their mlock limmit.
+ */
+
+ /*
+ * 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);
+ }
+}
+
+static int arm_spe_recording_options(struct auxtrace_record *itr,
+ struct evlist *evlist,
+ struct record_opts *opts)
+{
+ struct arm_spe_recording *sper =
+ container_of(itr, struct arm_spe_recording, itr);
+ struct perf_pmu *arm_spe_pmu = sper->arm_spe_pmu;
+ struct evsel *evsel, *arm_spe_evsel = NULL;
+ struct perf_cpu_map *cpus = evlist->core.user_requested_cpus;
+ bool privileged = perf_event_paranoid_check(-1);
+ struct evsel *tracking_evsel;
+ int err;
+ u64 bit;
+
+ sper->evlist = evlist;
+
+ evlist__for_each_entry(evlist, evsel) {
+ if (evsel->core.attr.type == arm_spe_pmu->type) {
+ if (arm_spe_evsel) {
+ pr_err("There may be only one " ARM_SPE_PMU_NAME "x event\n");
+ return -EINVAL;
+ }
+ evsel->core.attr.freq = 0;
+ evsel->core.attr.sample_period = arm_spe_pmu->default_config->sample_period;
+ evsel->needs_auxtrace_mmap = true;
+ arm_spe_evsel = evsel;
+ opts->full_auxtrace = true;
+ }
+ }
+
+ if (!opts->full_auxtrace)
+ return 0;
+
+ /*
+ * we are in snapshot mode.
+ */
+ if (opts->auxtrace_snapshot_mode) {
+ /*
+ * Command arguments '-Sxyz' and/or '-m,xyz' are missing, so fill those in with
+ * default values.
+ */
+ if (!opts->auxtrace_snapshot_size || !opts->auxtrace_mmap_pages)
+ arm_spe_snapshot_resolve_auxtrace_defaults(opts, privileged);
+
+ /*
+ * Snapshot 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->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 */
+ if (opts->auxtrace_mmap_pages) {
+ size_t sz = opts->auxtrace_mmap_pages * (size_t)page_size;
+ size_t min_sz = KiB(8);
+
+ if (sz < min_sz || !is_power_of_2(sz)) {
+ pr_err("Invalid mmap size for ARM SPE: must be at least %zuKiB and a power of 2\n",
+ min_sz / 1024);
+ return -EINVAL;
+ }
+ }
+
+ if (opts->auxtrace_snapshot_mode)
+ pr_debug2("%sx snapshot size: %zu\n", ARM_SPE_PMU_NAME,
+ opts->auxtrace_snapshot_size);
+
+ /*
+ * To obtain the auxtrace buffer file descriptor, the auxtrace event
+ * must come first.
+ */
+ evlist__to_front(evlist, arm_spe_evsel);
+
+ /*
+ * In the case of per-cpu mmaps, sample CPU for AUX event;
+ * also enable the timestamp tracing for samples correlation.
+ */
+ if (!perf_cpu_map__empty(cpus)) {
+ evsel__set_sample_bit(arm_spe_evsel, CPU);
+ arm_spe_set_timestamp(itr, arm_spe_evsel);
+ }
+
+ /*
+ * Set this only so that perf report knows that SPE generates memory info. It has no effect
+ * on the opening of the event or the SPE data produced.
+ */
+ evsel__set_sample_bit(arm_spe_evsel, DATA_SRC);
+
+ /*
+ * The PHYS_ADDR flag does not affect the driver behaviour, it is used to
+ * inform that the resulting output's SPE samples contain physical addresses
+ * where applicable.
+ */
+ bit = perf_pmu__format_bits(&arm_spe_pmu->format, "pa_enable");
+ if (arm_spe_evsel->core.attr.config & bit)
+ evsel__set_sample_bit(arm_spe_evsel, PHYS_ADDR);
+
+ /* Add dummy event to keep tracking */
+ err = parse_event(evlist, "dummy:u");
+ if (err)
+ return err;
+
+ tracking_evsel = evlist__last(evlist);
+ 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);
+ evsel__set_sample_bit(tracking_evsel, CPU);
+
+ /* also track task context switch */
+ if (!record_opts__no_switch_events(opts))
+ tracking_evsel->core.attr.context_switch = 1;
+ }
+
+ return 0;
+}
+
+static int arm_spe_parse_snapshot_options(struct auxtrace_record *itr __maybe_unused,
+ struct record_opts *opts,
+ const char *str)
+{
+ 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;
+
+ return 0;
+}
+
+static int arm_spe_snapshot_start(struct auxtrace_record *itr)
+{
+ struct arm_spe_recording *ptr =
+ container_of(itr, struct arm_spe_recording, itr);
+ struct evsel *evsel;
+
+ evlist__for_each_entry(ptr->evlist, evsel) {
+ if (evsel->core.attr.type == ptr->arm_spe_pmu->type)
+ return evsel__disable(evsel);
+ }
+ return -EINVAL;
+}
+
+static int arm_spe_snapshot_finish(struct auxtrace_record *itr)
+{
+ struct arm_spe_recording *ptr =
+ container_of(itr, struct arm_spe_recording, itr);
+ struct evsel *evsel;
+
+ evlist__for_each_entry(ptr->evlist, evsel) {
+ if (evsel->core.attr.type == ptr->arm_spe_pmu->type)
+ return evsel__enable(evsel);
+ }
+ return -EINVAL;
+}
+
+static int arm_spe_alloc_wrapped_array(struct arm_spe_recording *ptr, int idx)
+{
+ bool *wrapped;
+ int cnt = ptr->wrapped_cnt, new_cnt, i;
+
+ /*
+ * No need to allocate, so return early.
+ */
+ if (idx < cnt)
+ return 0;
+
+ /*
+ * Make ptr->wrapped as big as idx.
+ */
+ new_cnt = idx + 1;
+
+ /*
+ * Free'ed in arm_spe_recording_free().
+ */
+ wrapped = reallocarray(ptr->wrapped, new_cnt, sizeof(bool));
+ if (!wrapped)
+ return -ENOMEM;
+
+ /*
+ * init new allocated values.
+ */
+ for (i = cnt; i < new_cnt; i++)
+ wrapped[i] = false;
+
+ ptr->wrapped_cnt = new_cnt;
+ ptr->wrapped = wrapped;
+
+ return 0;
+}
+
+static bool arm_spe_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;
+
+ /*
+ * Defensively handle the case where head might be continually increasing - if its value is
+ * equal or greater than the size of the ring buffer, then we can safely determine it has
+ * wrapped around. Otherwise, continue to detect if head might have wrapped.
+ */
+ if (head >= buffer_size)
+ return true;
+
+ /*
+ * We want to look the very last 512 byte (chosen arbitrarily) in the ring buffer.
+ */
+ watermark = buf_size - 512;
+
+ /*
+ * 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 /= sizeof(u64);
+ buf_size /= sizeof(u64);
+
+ /*
+ * 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 arm_spe_find_snapshot(struct auxtrace_record *itr, int idx,
+ struct auxtrace_mmap *mm, unsigned char *data,
+ u64 *head, u64 *old)
+{
+ int err;
+ bool wrapped;
+ struct arm_spe_recording *ptr =
+ container_of(itr, struct arm_spe_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 = arm_spe_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 && arm_spe_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 u64 arm_spe_reference(struct auxtrace_record *itr __maybe_unused)
+{
+ struct timespec ts;
+
+ clock_gettime(CLOCK_MONOTONIC_RAW, &ts);
+
+ return ts.tv_sec ^ ts.tv_nsec;
+}
+
+static void arm_spe_recording_free(struct auxtrace_record *itr)
+{
+ struct arm_spe_recording *sper =
+ container_of(itr, struct arm_spe_recording, itr);
+
+ free(sper->wrapped);
+ free(sper);
+}
+
+struct auxtrace_record *arm_spe_recording_init(int *err,
+ struct perf_pmu *arm_spe_pmu)
+{
+ struct arm_spe_recording *sper;
+
+ if (!arm_spe_pmu) {
+ *err = -ENODEV;
+ return NULL;
+ }
+
+ sper = zalloc(sizeof(struct arm_spe_recording));
+ if (!sper) {
+ *err = -ENOMEM;
+ return NULL;
+ }
+
+ sper->arm_spe_pmu = arm_spe_pmu;
+ sper->itr.pmu = arm_spe_pmu;
+ sper->itr.snapshot_start = arm_spe_snapshot_start;
+ sper->itr.snapshot_finish = arm_spe_snapshot_finish;
+ sper->itr.find_snapshot = arm_spe_find_snapshot;
+ sper->itr.parse_snapshot_options = arm_spe_parse_snapshot_options;
+ sper->itr.recording_options = arm_spe_recording_options;
+ sper->itr.info_priv_size = arm_spe_info_priv_size;
+ sper->itr.info_fill = arm_spe_info_fill;
+ sper->itr.free = arm_spe_recording_free;
+ sper->itr.reference = arm_spe_reference;
+ sper->itr.read_finish = auxtrace_record__read_finish;
+ sper->itr.alignment = 0;
+
+ *err = 0;
+ return &sper->itr;
+}
+
+struct perf_event_attr
+*arm_spe_pmu_default_config(struct perf_pmu *arm_spe_pmu)
+{
+ struct perf_event_attr *attr;
+
+ attr = zalloc(sizeof(struct perf_event_attr));
+ if (!attr) {
+ pr_err("arm_spe default config cannot allocate a perf_event_attr\n");
+ return NULL;
+ }
+
+ /*
+ * If kernel driver doesn't advertise a minimum,
+ * use max allowable by PMSIDR_EL1.INTERVAL
+ */
+ if (perf_pmu__scan_file(arm_spe_pmu, "caps/min_interval", "%llu",
+ &attr->sample_period) != 1) {
+ pr_debug("arm_spe driver doesn't advertise a min. interval. Using 4096\n");
+ attr->sample_period = 4096;
+ }
+
+ arm_spe_pmu->selectable = true;
+ arm_spe_pmu->is_uncore = false;
+
+ return attr;
+}
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