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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /tools/perf/arch/x86/util/intel-pt.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | tools/perf/arch/x86/util/intel-pt.c | 1221 |
1 files changed, 1221 insertions, 0 deletions
diff --git a/tools/perf/arch/x86/util/intel-pt.c b/tools/perf/arch/x86/util/intel-pt.c new file mode 100644 index 000000000..082e5f2a4 --- /dev/null +++ b/tools/perf/arch/x86/util/intel-pt.c @@ -0,0 +1,1221 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * intel_pt.c: Intel Processor Trace support + * Copyright (c) 2013-2015, Intel Corporation. + */ + +#include <errno.h> +#include <stdbool.h> +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/bitops.h> +#include <linux/log2.h> +#include <linux/zalloc.h> +#include <cpuid.h> + +#include "../../../util/session.h" +#include "../../../util/event.h" +#include "../../../util/evlist.h" +#include "../../../util/evsel.h" +#include "../../../util/evsel_config.h" +#include "../../../util/cpumap.h" +#include "../../../util/mmap.h" +#include <subcmd/parse-options.h> +#include "../../../util/parse-events.h" +#include "../../../util/pmu.h" +#include "../../../util/debug.h" +#include "../../../util/auxtrace.h" +#include "../../../util/perf_api_probe.h" +#include "../../../util/record.h" +#include "../../../util/target.h" +#include "../../../util/tsc.h" +#include <internal/lib.h> // page_size +#include "../../../util/intel-pt.h" + +#define KiB(x) ((x) * 1024) +#define MiB(x) ((x) * 1024 * 1024) +#define KiB_MASK(x) (KiB(x) - 1) +#define MiB_MASK(x) (MiB(x) - 1) + +#define INTEL_PT_PSB_PERIOD_NEAR 256 + +struct intel_pt_snapshot_ref { + void *ref_buf; + size_t ref_offset; + bool wrapped; +}; + +struct intel_pt_recording { + struct auxtrace_record itr; + struct perf_pmu *intel_pt_pmu; + int have_sched_switch; + struct evlist *evlist; + bool snapshot_mode; + bool snapshot_init_done; + size_t snapshot_size; + size_t snapshot_ref_buf_size; + int snapshot_ref_cnt; + struct intel_pt_snapshot_ref *snapshot_refs; + size_t priv_size; +}; + +static int intel_pt_parse_terms_with_default(const char *pmu_name, + struct list_head *formats, + const char *str, + u64 *config) +{ + struct list_head *terms; + struct perf_event_attr attr = { .size = 0, }; + int err; + + terms = malloc(sizeof(struct list_head)); + if (!terms) + return -ENOMEM; + + INIT_LIST_HEAD(terms); + + err = parse_events_terms(terms, str); + if (err) + goto out_free; + + attr.config = *config; + err = perf_pmu__config_terms(pmu_name, formats, &attr, terms, true, + NULL); + if (err) + goto out_free; + + *config = attr.config; +out_free: + parse_events_terms__delete(terms); + return err; +} + +static int intel_pt_parse_terms(const char *pmu_name, struct list_head *formats, + const char *str, u64 *config) +{ + *config = 0; + return intel_pt_parse_terms_with_default(pmu_name, formats, str, + config); +} + +static u64 intel_pt_masked_bits(u64 mask, u64 bits) +{ + const u64 top_bit = 1ULL << 63; + u64 res = 0; + int i; + + for (i = 0; i < 64; i++) { + if (mask & top_bit) { + res <<= 1; + if (bits & top_bit) + res |= 1; + } + mask <<= 1; + bits <<= 1; + } + + return res; +} + +static int intel_pt_read_config(struct perf_pmu *intel_pt_pmu, const char *str, + struct evlist *evlist, u64 *res) +{ + struct evsel *evsel; + u64 mask; + + *res = 0; + + mask = perf_pmu__format_bits(&intel_pt_pmu->format, str); + if (!mask) + return -EINVAL; + + evlist__for_each_entry(evlist, evsel) { + if (evsel->core.attr.type == intel_pt_pmu->type) { + *res = intel_pt_masked_bits(mask, evsel->core.attr.config); + return 0; + } + } + + return -EINVAL; +} + +static size_t intel_pt_psb_period(struct perf_pmu *intel_pt_pmu, + struct evlist *evlist) +{ + u64 val; + int err, topa_multiple_entries; + size_t psb_period; + + if (perf_pmu__scan_file(intel_pt_pmu, "caps/topa_multiple_entries", + "%d", &topa_multiple_entries) != 1) + topa_multiple_entries = 0; + + /* + * Use caps/topa_multiple_entries to indicate early hardware that had + * extra frequent PSBs. + */ + if (!topa_multiple_entries) { + psb_period = 256; + goto out; + } + + err = intel_pt_read_config(intel_pt_pmu, "psb_period", evlist, &val); + if (err) + val = 0; + + psb_period = 1 << (val + 11); +out: + pr_debug2("%s psb_period %zu\n", intel_pt_pmu->name, psb_period); + return psb_period; +} + +static int intel_pt_pick_bit(int bits, int target) +{ + int pos, pick = -1; + + for (pos = 0; bits; bits >>= 1, pos++) { + if (bits & 1) { + if (pos <= target || pick < 0) + pick = pos; + if (pos >= target) + break; + } + } + + return pick; +} + +static u64 intel_pt_default_config(struct perf_pmu *intel_pt_pmu) +{ + char buf[256]; + int mtc, mtc_periods = 0, mtc_period; + int psb_cyc, psb_periods, psb_period; + int pos = 0; + u64 config; + char c; + + pos += scnprintf(buf + pos, sizeof(buf) - pos, "tsc"); + + if (perf_pmu__scan_file(intel_pt_pmu, "caps/mtc", "%d", + &mtc) != 1) + mtc = 1; + + if (mtc) { + if (perf_pmu__scan_file(intel_pt_pmu, "caps/mtc_periods", "%x", + &mtc_periods) != 1) + mtc_periods = 0; + if (mtc_periods) { + mtc_period = intel_pt_pick_bit(mtc_periods, 3); + pos += scnprintf(buf + pos, sizeof(buf) - pos, + ",mtc,mtc_period=%d", mtc_period); + } + } + + if (perf_pmu__scan_file(intel_pt_pmu, "caps/psb_cyc", "%d", + &psb_cyc) != 1) + psb_cyc = 1; + + if (psb_cyc && mtc_periods) { + if (perf_pmu__scan_file(intel_pt_pmu, "caps/psb_periods", "%x", + &psb_periods) != 1) + psb_periods = 0; + if (psb_periods) { + psb_period = intel_pt_pick_bit(psb_periods, 3); + pos += scnprintf(buf + pos, sizeof(buf) - pos, + ",psb_period=%d", psb_period); + } + } + + if (perf_pmu__scan_file(intel_pt_pmu, "format/pt", "%c", &c) == 1 && + perf_pmu__scan_file(intel_pt_pmu, "format/branch", "%c", &c) == 1) + pos += scnprintf(buf + pos, sizeof(buf) - pos, ",pt,branch"); + + pr_debug2("%s default config: %s\n", intel_pt_pmu->name, buf); + + intel_pt_parse_terms(intel_pt_pmu->name, &intel_pt_pmu->format, buf, + &config); + + return config; +} + +static int intel_pt_parse_snapshot_options(struct auxtrace_record *itr, + struct record_opts *opts, + const char *str) +{ + struct intel_pt_recording *ptr = + container_of(itr, struct intel_pt_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; +} + +struct perf_event_attr * +intel_pt_pmu_default_config(struct perf_pmu *intel_pt_pmu) +{ + struct perf_event_attr *attr; + + attr = zalloc(sizeof(struct perf_event_attr)); + if (!attr) + return NULL; + + attr->config = intel_pt_default_config(intel_pt_pmu); + + intel_pt_pmu->selectable = true; + + return attr; +} + +static const char *intel_pt_find_filter(struct evlist *evlist, + struct perf_pmu *intel_pt_pmu) +{ + struct evsel *evsel; + + evlist__for_each_entry(evlist, evsel) { + if (evsel->core.attr.type == intel_pt_pmu->type) + return evsel->filter; + } + + return NULL; +} + +static size_t intel_pt_filter_bytes(const char *filter) +{ + size_t len = filter ? strlen(filter) : 0; + + return len ? roundup(len + 1, 8) : 0; +} + +static size_t +intel_pt_info_priv_size(struct auxtrace_record *itr, struct evlist *evlist) +{ + struct intel_pt_recording *ptr = + container_of(itr, struct intel_pt_recording, itr); + const char *filter = intel_pt_find_filter(evlist, ptr->intel_pt_pmu); + + ptr->priv_size = (INTEL_PT_AUXTRACE_PRIV_MAX * sizeof(u64)) + + intel_pt_filter_bytes(filter); + + return ptr->priv_size; +} + +static void intel_pt_tsc_ctc_ratio(u32 *n, u32 *d) +{ + unsigned int eax = 0, ebx = 0, ecx = 0, edx = 0; + + __get_cpuid(0x15, &eax, &ebx, &ecx, &edx); + *n = ebx; + *d = eax; +} + +static int intel_pt_info_fill(struct auxtrace_record *itr, + struct perf_session *session, + struct perf_record_auxtrace_info *auxtrace_info, + size_t priv_size) +{ + struct intel_pt_recording *ptr = + container_of(itr, struct intel_pt_recording, itr); + struct perf_pmu *intel_pt_pmu = ptr->intel_pt_pmu; + struct perf_event_mmap_page *pc; + struct perf_tsc_conversion tc = { .time_mult = 0, }; + bool cap_user_time_zero = false, per_cpu_mmaps; + u64 tsc_bit, mtc_bit, mtc_freq_bits, cyc_bit, noretcomp_bit; + u32 tsc_ctc_ratio_n, tsc_ctc_ratio_d; + unsigned long max_non_turbo_ratio; + size_t filter_str_len; + const char *filter; + __u64 *info; + int err; + + if (priv_size != ptr->priv_size) + return -EINVAL; + + intel_pt_parse_terms(intel_pt_pmu->name, &intel_pt_pmu->format, + "tsc", &tsc_bit); + intel_pt_parse_terms(intel_pt_pmu->name, &intel_pt_pmu->format, + "noretcomp", &noretcomp_bit); + intel_pt_parse_terms(intel_pt_pmu->name, &intel_pt_pmu->format, + "mtc", &mtc_bit); + mtc_freq_bits = perf_pmu__format_bits(&intel_pt_pmu->format, + "mtc_period"); + intel_pt_parse_terms(intel_pt_pmu->name, &intel_pt_pmu->format, + "cyc", &cyc_bit); + + intel_pt_tsc_ctc_ratio(&tsc_ctc_ratio_n, &tsc_ctc_ratio_d); + + if (perf_pmu__scan_file(intel_pt_pmu, "max_nonturbo_ratio", + "%lu", &max_non_turbo_ratio) != 1) + max_non_turbo_ratio = 0; + + filter = intel_pt_find_filter(session->evlist, ptr->intel_pt_pmu); + filter_str_len = filter ? strlen(filter) : 0; + + if (!session->evlist->core.nr_mmaps) + return -EINVAL; + + pc = session->evlist->mmap[0].core.base; + if (pc) { + err = perf_read_tsc_conversion(pc, &tc); + if (err) { + if (err != -EOPNOTSUPP) + return err; + } else { + cap_user_time_zero = tc.time_mult != 0; + } + if (!cap_user_time_zero) + ui__warning("Intel Processor Trace: TSC not available\n"); + } + + per_cpu_mmaps = !perf_cpu_map__empty(session->evlist->core.cpus); + + auxtrace_info->type = PERF_AUXTRACE_INTEL_PT; + auxtrace_info->priv[INTEL_PT_PMU_TYPE] = intel_pt_pmu->type; + auxtrace_info->priv[INTEL_PT_TIME_SHIFT] = tc.time_shift; + auxtrace_info->priv[INTEL_PT_TIME_MULT] = tc.time_mult; + auxtrace_info->priv[INTEL_PT_TIME_ZERO] = tc.time_zero; + auxtrace_info->priv[INTEL_PT_CAP_USER_TIME_ZERO] = cap_user_time_zero; + auxtrace_info->priv[INTEL_PT_TSC_BIT] = tsc_bit; + auxtrace_info->priv[INTEL_PT_NORETCOMP_BIT] = noretcomp_bit; + auxtrace_info->priv[INTEL_PT_HAVE_SCHED_SWITCH] = ptr->have_sched_switch; + auxtrace_info->priv[INTEL_PT_SNAPSHOT_MODE] = ptr->snapshot_mode; + auxtrace_info->priv[INTEL_PT_PER_CPU_MMAPS] = per_cpu_mmaps; + auxtrace_info->priv[INTEL_PT_MTC_BIT] = mtc_bit; + auxtrace_info->priv[INTEL_PT_MTC_FREQ_BITS] = mtc_freq_bits; + auxtrace_info->priv[INTEL_PT_TSC_CTC_N] = tsc_ctc_ratio_n; + auxtrace_info->priv[INTEL_PT_TSC_CTC_D] = tsc_ctc_ratio_d; + auxtrace_info->priv[INTEL_PT_CYC_BIT] = cyc_bit; + auxtrace_info->priv[INTEL_PT_MAX_NONTURBO_RATIO] = max_non_turbo_ratio; + auxtrace_info->priv[INTEL_PT_FILTER_STR_LEN] = filter_str_len; + + info = &auxtrace_info->priv[INTEL_PT_FILTER_STR_LEN] + 1; + + if (filter_str_len) { + size_t len = intel_pt_filter_bytes(filter); + + strncpy((char *)info, filter, len); + info += len >> 3; + } + + return 0; +} + +static int intel_pt_track_switches(struct evlist *evlist) +{ + const char *sched_switch = "sched:sched_switch"; + struct evsel *evsel; + int err; + + if (!perf_evlist__can_select_event(evlist, sched_switch)) + return -EPERM; + + err = parse_events(evlist, sched_switch, NULL); + if (err) { + pr_debug2("%s: failed to parse %s, error %d\n", + __func__, sched_switch, err); + return err; + } + + evsel = evlist__last(evlist); + + evsel__set_sample_bit(evsel, CPU); + evsel__set_sample_bit(evsel, TIME); + + evsel->core.system_wide = true; + evsel->no_aux_samples = true; + evsel->immediate = true; + + return 0; +} + +static void intel_pt_valid_str(char *str, size_t len, u64 valid) +{ + unsigned int val, last = 0, state = 1; + int p = 0; + + str[0] = '\0'; + + for (val = 0; val <= 64; val++, valid >>= 1) { + if (valid & 1) { + last = val; + switch (state) { + case 0: + p += scnprintf(str + p, len - p, ","); + /* Fall through */ + case 1: + p += scnprintf(str + p, len - p, "%u", val); + state = 2; + break; + case 2: + state = 3; + break; + case 3: + state = 4; + break; + default: + break; + } + } else { + switch (state) { + case 3: + p += scnprintf(str + p, len - p, ",%u", last); + state = 0; + break; + case 4: + p += scnprintf(str + p, len - p, "-%u", last); + state = 0; + break; + default: + break; + } + if (state != 1) + state = 0; + } + } +} + +static int intel_pt_val_config_term(struct perf_pmu *intel_pt_pmu, + const char *caps, const char *name, + const char *supported, u64 config) +{ + char valid_str[256]; + unsigned int shift; + unsigned long long valid; + u64 bits; + int ok; + + if (perf_pmu__scan_file(intel_pt_pmu, caps, "%llx", &valid) != 1) + valid = 0; + + if (supported && + perf_pmu__scan_file(intel_pt_pmu, supported, "%d", &ok) == 1 && !ok) + valid = 0; + + valid |= 1; + + bits = perf_pmu__format_bits(&intel_pt_pmu->format, name); + + config &= bits; + + for (shift = 0; bits && !(bits & 1); shift++) + bits >>= 1; + + config >>= shift; + + if (config > 63) + goto out_err; + + if (valid & (1 << config)) + return 0; +out_err: + intel_pt_valid_str(valid_str, sizeof(valid_str), valid); + pr_err("Invalid %s for %s. Valid values are: %s\n", + name, INTEL_PT_PMU_NAME, valid_str); + return -EINVAL; +} + +static int intel_pt_validate_config(struct perf_pmu *intel_pt_pmu, + struct evsel *evsel) +{ + int err; + char c; + + if (!evsel) + return 0; + + /* + * If supported, force pass-through config term (pt=1) even if user + * sets pt=0, which avoids senseless kernel errors. + */ + if (perf_pmu__scan_file(intel_pt_pmu, "format/pt", "%c", &c) == 1 && + !(evsel->core.attr.config & 1)) { + pr_warning("pt=0 doesn't make sense, forcing pt=1\n"); + evsel->core.attr.config |= 1; + } + + err = intel_pt_val_config_term(intel_pt_pmu, "caps/cycle_thresholds", + "cyc_thresh", "caps/psb_cyc", + evsel->core.attr.config); + if (err) + return err; + + err = intel_pt_val_config_term(intel_pt_pmu, "caps/mtc_periods", + "mtc_period", "caps/mtc", + evsel->core.attr.config); + if (err) + return err; + + return intel_pt_val_config_term(intel_pt_pmu, "caps/psb_periods", + "psb_period", "caps/psb_cyc", + evsel->core.attr.config); +} + +static void intel_pt_config_sample_mode(struct perf_pmu *intel_pt_pmu, + struct evsel *evsel) +{ + u64 user_bits = 0, bits; + struct evsel_config_term *term = evsel__get_config_term(evsel, CFG_CHG); + + if (term) + user_bits = term->val.cfg_chg; + + bits = perf_pmu__format_bits(&intel_pt_pmu->format, "psb_period"); + + /* Did user change psb_period */ + if (bits & user_bits) + return; + + /* Set psb_period to 0 */ + evsel->core.attr.config &= ~bits; +} + +static void intel_pt_min_max_sample_sz(struct evlist *evlist, + size_t *min_sz, size_t *max_sz) +{ + struct evsel *evsel; + + evlist__for_each_entry(evlist, evsel) { + size_t sz = evsel->core.attr.aux_sample_size; + + if (!sz) + continue; + if (min_sz && (sz < *min_sz || !*min_sz)) + *min_sz = sz; + if (max_sz && sz > *max_sz) + *max_sz = sz; + } +} + +/* + * Currently, there is not enough information to disambiguate different PEBS + * events, so only allow one. + */ +static bool intel_pt_too_many_aux_output(struct evlist *evlist) +{ + struct evsel *evsel; + int aux_output_cnt = 0; + + evlist__for_each_entry(evlist, evsel) + aux_output_cnt += !!evsel->core.attr.aux_output; + + if (aux_output_cnt > 1) { + pr_err(INTEL_PT_PMU_NAME " supports at most one event with aux-output\n"); + return true; + } + + return false; +} + +static int intel_pt_recording_options(struct auxtrace_record *itr, + struct evlist *evlist, + struct record_opts *opts) +{ + struct intel_pt_recording *ptr = + container_of(itr, struct intel_pt_recording, itr); + struct perf_pmu *intel_pt_pmu = ptr->intel_pt_pmu; + bool have_timing_info, need_immediate = false; + struct evsel *evsel, *intel_pt_evsel = NULL; + const struct perf_cpu_map *cpus = evlist->core.cpus; + bool privileged = perf_event_paranoid_check(-1); + u64 tsc_bit; + int err; + + ptr->evlist = evlist; + ptr->snapshot_mode = opts->auxtrace_snapshot_mode; + + evlist__for_each_entry(evlist, evsel) { + if (evsel->core.attr.type == intel_pt_pmu->type) { + if (intel_pt_evsel) { + pr_err("There may be only one " INTEL_PT_PMU_NAME " event\n"); + return -EINVAL; + } + evsel->core.attr.freq = 0; + evsel->core.attr.sample_period = 1; + evsel->no_aux_samples = true; + intel_pt_evsel = evsel; + opts->full_auxtrace = true; + } + } + + if (opts->auxtrace_snapshot_mode && !opts->full_auxtrace) { + pr_err("Snapshot mode (-S option) requires " INTEL_PT_PMU_NAME " PMU event (-e " INTEL_PT_PMU_NAME ")\n"); + return -EINVAL; + } + + if (opts->auxtrace_snapshot_mode && opts->auxtrace_sample_mode) { + pr_err("Snapshot mode (" INTEL_PT_PMU_NAME " PMU) and sample trace cannot be used together\n"); + return -EINVAL; + } + + if (opts->use_clockid) { + pr_err("Cannot use clockid (-k option) with " INTEL_PT_PMU_NAME "\n"); + return -EINVAL; + } + + if (intel_pt_too_many_aux_output(evlist)) + return -EINVAL; + + if (!opts->full_auxtrace) + return 0; + + if (opts->auxtrace_sample_mode) + intel_pt_config_sample_mode(intel_pt_pmu, intel_pt_evsel); + + err = intel_pt_validate_config(intel_pt_pmu, intel_pt_evsel); + if (err) + return err; + + /* Set default sizes for snapshot mode */ + if (opts->auxtrace_snapshot_mode) { + size_t psb_period = intel_pt_psb_period(intel_pt_pmu, evlist); + + 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; + } + if (!opts->auxtrace_snapshot_size) + opts->auxtrace_snapshot_size = + opts->auxtrace_mmap_pages * (size_t)page_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); + } + 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; + } + 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; + } + pr_debug2("Intel PT snapshot size: %zu\n", + opts->auxtrace_snapshot_size); + if (psb_period && + opts->auxtrace_snapshot_size <= psb_period + + INTEL_PT_PSB_PERIOD_NEAR) + ui__warning("Intel PT snapshot size (%zu) may be too small for PSB period (%zu)\n", + opts->auxtrace_snapshot_size, psb_period); + } + + /* Set default sizes for sample mode */ + if (opts->auxtrace_sample_mode) { + size_t psb_period = intel_pt_psb_period(intel_pt_pmu, evlist); + size_t min_sz = 0, max_sz = 0; + + intel_pt_min_max_sample_sz(evlist, &min_sz, &max_sz); + if (!opts->auxtrace_mmap_pages && !privileged && + opts->mmap_pages == UINT_MAX) + opts->mmap_pages = KiB(256) / page_size; + if (!opts->auxtrace_mmap_pages) { + size_t sz = round_up(max_sz, page_size) / page_size; + + opts->auxtrace_mmap_pages = roundup_pow_of_two(sz); + } + if (max_sz > opts->auxtrace_mmap_pages * (size_t)page_size) { + pr_err("Sample size %zu must not be greater than AUX area tracing mmap size %zu\n", + max_sz, + opts->auxtrace_mmap_pages * (size_t)page_size); + return -EINVAL; + } + pr_debug2("Intel PT min. sample size: %zu max. sample size: %zu\n", + min_sz, max_sz); + if (psb_period && + min_sz <= psb_period + INTEL_PT_PSB_PERIOD_NEAR) + ui__warning("Intel PT sample size (%zu) may be too small for PSB period (%zu)\n", + min_sz, psb_period); + } + + /* Set default sizes for full trace mode */ + 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 */ + if (opts->auxtrace_mmap_pages) { + size_t sz = opts->auxtrace_mmap_pages * (size_t)page_size; + size_t min_sz; + + if (opts->auxtrace_snapshot_mode || opts->auxtrace_sample_mode) + min_sz = KiB(4); + else + min_sz = KiB(8); + + if (sz < min_sz || !is_power_of_2(sz)) { + pr_err("Invalid mmap size for Intel Processor Trace: must be at least %zuKiB and a power of 2\n", + min_sz / 1024); + return -EINVAL; + } + } + + intel_pt_parse_terms(intel_pt_pmu->name, &intel_pt_pmu->format, + "tsc", &tsc_bit); + + if (opts->full_auxtrace && (intel_pt_evsel->core.attr.config & tsc_bit)) + have_timing_info = true; + else + have_timing_info = false; + + /* + * Per-cpu recording needs sched_switch events to distinguish different + * threads. + */ + if (have_timing_info && !perf_cpu_map__empty(cpus) && + !record_opts__no_switch_events(opts)) { + if (perf_can_record_switch_events()) { + bool cpu_wide = !target__none(&opts->target) && + !target__has_task(&opts->target); + + if (!cpu_wide && perf_can_record_cpu_wide()) { + struct evsel *switch_evsel; + + err = parse_events(evlist, "dummy:u", NULL); + if (err) + return err; + + switch_evsel = evlist__last(evlist); + + switch_evsel->core.attr.freq = 0; + switch_evsel->core.attr.sample_period = 1; + switch_evsel->core.attr.context_switch = 1; + + switch_evsel->core.system_wide = true; + switch_evsel->no_aux_samples = true; + switch_evsel->immediate = true; + + evsel__set_sample_bit(switch_evsel, TID); + evsel__set_sample_bit(switch_evsel, TIME); + evsel__set_sample_bit(switch_evsel, CPU); + evsel__reset_sample_bit(switch_evsel, BRANCH_STACK); + + opts->record_switch_events = false; + ptr->have_sched_switch = 3; + } else { + opts->record_switch_events = true; + need_immediate = true; + if (cpu_wide) + ptr->have_sched_switch = 3; + else + ptr->have_sched_switch = 2; + } + } else { + err = intel_pt_track_switches(evlist); + if (err == -EPERM) + pr_debug2("Unable to select sched:sched_switch\n"); + else if (err) + return err; + else + ptr->have_sched_switch = 1; + } + } + + if (have_timing_info && !intel_pt_evsel->core.attr.exclude_kernel && + perf_can_record_text_poke_events() && perf_can_record_cpu_wide()) + opts->text_poke = true; + + if (intel_pt_evsel) { + /* + * To obtain the auxtrace buffer file descriptor, the auxtrace + * event must come first. + */ + perf_evlist__to_front(evlist, intel_pt_evsel); + /* + * In the case of per-cpu mmaps, we need the CPU on the + * AUX event. + */ + if (!perf_cpu_map__empty(cpus)) + evsel__set_sample_bit(intel_pt_evsel, CPU); + } + + /* Add dummy event to keep tracking */ + if (opts->full_auxtrace) { + struct evsel *tracking_evsel; + + err = parse_events(evlist, "dummy:u", NULL); + if (err) + return err; + + 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; + + tracking_evsel->no_aux_samples = true; + if (need_immediate) + tracking_evsel->immediate = true; + + /* 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); + /* And the CPU for switch events */ + evsel__set_sample_bit(tracking_evsel, CPU); + } + evsel__reset_sample_bit(tracking_evsel, BRANCH_STACK); + } + + /* + * Warn the user when we do not have enough information to decode i.e. + * per-cpu with no sched_switch (except workload-only). + */ + if (!ptr->have_sched_switch && !perf_cpu_map__empty(cpus) && + !target__none(&opts->target) && + !intel_pt_evsel->core.attr.exclude_user) + ui__warning("Intel Processor Trace decoding will not be possible except for kernel tracing!\n"); + + return 0; +} + +static int intel_pt_snapshot_start(struct auxtrace_record *itr) +{ + struct intel_pt_recording *ptr = + container_of(itr, struct intel_pt_recording, itr); + struct evsel *evsel; + + evlist__for_each_entry(ptr->evlist, evsel) { + if (evsel->core.attr.type == ptr->intel_pt_pmu->type) + return evsel__disable(evsel); + } + return -EINVAL; +} + +static int intel_pt_snapshot_finish(struct auxtrace_record *itr) +{ + struct intel_pt_recording *ptr = + container_of(itr, struct intel_pt_recording, itr); + struct evsel *evsel; + + evlist__for_each_entry(ptr->evlist, evsel) { + if (evsel->core.attr.type == ptr->intel_pt_pmu->type) + return evsel__enable(evsel); + } + return -EINVAL; +} + +static int intel_pt_alloc_snapshot_refs(struct intel_pt_recording *ptr, int idx) +{ + const size_t sz = sizeof(struct intel_pt_snapshot_ref); + int cnt = ptr->snapshot_ref_cnt, new_cnt = cnt * 2; + struct intel_pt_snapshot_ref *refs; + + if (!new_cnt) + new_cnt = 16; + + while (new_cnt <= idx) + new_cnt *= 2; + + refs = calloc(new_cnt, sz); + if (!refs) + return -ENOMEM; + + memcpy(refs, ptr->snapshot_refs, cnt * sz); + + ptr->snapshot_refs = refs; + ptr->snapshot_ref_cnt = new_cnt; + + return 0; +} + +static void intel_pt_free_snapshot_refs(struct intel_pt_recording *ptr) +{ + int i; + + for (i = 0; i < ptr->snapshot_ref_cnt; i++) + zfree(&ptr->snapshot_refs[i].ref_buf); + zfree(&ptr->snapshot_refs); +} + +static void intel_pt_recording_free(struct auxtrace_record *itr) +{ + struct intel_pt_recording *ptr = + container_of(itr, struct intel_pt_recording, itr); + + intel_pt_free_snapshot_refs(ptr); + free(ptr); +} + +static int intel_pt_alloc_snapshot_ref(struct intel_pt_recording *ptr, int idx, + size_t snapshot_buf_size) +{ + size_t ref_buf_size = ptr->snapshot_ref_buf_size; + void *ref_buf; + + ref_buf = zalloc(ref_buf_size); + if (!ref_buf) + return -ENOMEM; + + ptr->snapshot_refs[idx].ref_buf = ref_buf; + ptr->snapshot_refs[idx].ref_offset = snapshot_buf_size - ref_buf_size; + + return 0; +} + +static size_t intel_pt_snapshot_ref_buf_size(struct intel_pt_recording *ptr, + size_t snapshot_buf_size) +{ + const size_t max_size = 256 * 1024; + size_t buf_size = 0, psb_period; + + if (ptr->snapshot_size <= 64 * 1024) + return 0; + + psb_period = intel_pt_psb_period(ptr->intel_pt_pmu, ptr->evlist); + if (psb_period) + buf_size = psb_period * 2; + + if (!buf_size || buf_size > max_size) + buf_size = max_size; + + if (buf_size >= snapshot_buf_size) + return 0; + + if (buf_size >= ptr->snapshot_size / 2) + return 0; + + return buf_size; +} + +static int intel_pt_snapshot_init(struct intel_pt_recording *ptr, + size_t snapshot_buf_size) +{ + if (ptr->snapshot_init_done) + return 0; + + ptr->snapshot_init_done = true; + + ptr->snapshot_ref_buf_size = intel_pt_snapshot_ref_buf_size(ptr, + snapshot_buf_size); + + return 0; +} + +/** + * intel_pt_compare_buffers - compare bytes in a buffer to a circular buffer. + * @buf1: first buffer + * @compare_size: number of bytes to compare + * @buf2: second buffer (a circular buffer) + * @offs2: offset in second buffer + * @buf2_size: size of second buffer + * + * The comparison allows for the possibility that the bytes to compare in the + * circular buffer are not contiguous. It is assumed that @compare_size <= + * @buf2_size. This function returns %false if the bytes are identical, %true + * otherwise. + */ +static bool intel_pt_compare_buffers(void *buf1, size_t compare_size, + void *buf2, size_t offs2, size_t buf2_size) +{ + size_t end2 = offs2 + compare_size, part_size; + + if (end2 <= buf2_size) + return memcmp(buf1, buf2 + offs2, compare_size); + + part_size = end2 - buf2_size; + if (memcmp(buf1, buf2 + offs2, part_size)) + return true; + + compare_size -= part_size; + + return memcmp(buf1 + part_size, buf2, compare_size); +} + +static bool intel_pt_compare_ref(void *ref_buf, size_t ref_offset, + size_t ref_size, size_t buf_size, + void *data, size_t head) +{ + size_t ref_end = ref_offset + ref_size; + + if (ref_end > buf_size) { + if (head > ref_offset || head < ref_end - buf_size) + return true; + } else if (head > ref_offset && head < ref_end) { + return true; + } + + return intel_pt_compare_buffers(ref_buf, ref_size, data, ref_offset, + buf_size); +} + +static void intel_pt_copy_ref(void *ref_buf, size_t ref_size, size_t buf_size, + void *data, size_t head) +{ + if (head >= ref_size) { + memcpy(ref_buf, data + head - ref_size, ref_size); + } else { + memcpy(ref_buf, data, head); + ref_size -= head; + memcpy(ref_buf + head, data + buf_size - ref_size, ref_size); + } +} + +static bool intel_pt_wrapped(struct intel_pt_recording *ptr, int idx, + struct auxtrace_mmap *mm, unsigned char *data, + u64 head) +{ + struct intel_pt_snapshot_ref *ref = &ptr->snapshot_refs[idx]; + bool wrapped; + + wrapped = intel_pt_compare_ref(ref->ref_buf, ref->ref_offset, + ptr->snapshot_ref_buf_size, mm->len, + data, head); + + intel_pt_copy_ref(ref->ref_buf, ptr->snapshot_ref_buf_size, mm->len, + data, head); + + return wrapped; +} + +static bool intel_pt_first_wrap(u64 *data, size_t buf_size) +{ + int i, a, b; + + b = buf_size >> 3; + a = b - 512; + if (a < 0) + a = 0; + + for (i = a; i < b; i++) { + if (data[i]) + return true; + } + + return false; +} + +static int intel_pt_find_snapshot(struct auxtrace_record *itr, int idx, + struct auxtrace_mmap *mm, unsigned char *data, + u64 *head, u64 *old) +{ + struct intel_pt_recording *ptr = + container_of(itr, struct intel_pt_recording, itr); + bool wrapped; + int err; + + pr_debug3("%s: mmap index %d old head %zu new head %zu\n", + __func__, idx, (size_t)*old, (size_t)*head); + + err = intel_pt_snapshot_init(ptr, mm->len); + if (err) + goto out_err; + + if (idx >= ptr->snapshot_ref_cnt) { + err = intel_pt_alloc_snapshot_refs(ptr, idx); + if (err) + goto out_err; + } + + if (ptr->snapshot_ref_buf_size) { + if (!ptr->snapshot_refs[idx].ref_buf) { + err = intel_pt_alloc_snapshot_ref(ptr, idx, mm->len); + if (err) + goto out_err; + } + wrapped = intel_pt_wrapped(ptr, idx, mm, data, *head); + } else { + wrapped = ptr->snapshot_refs[idx].wrapped; + if (!wrapped && intel_pt_first_wrap((u64 *)data, mm->len)) { + ptr->snapshot_refs[idx].wrapped = true; + wrapped = true; + } + } + + /* + * In full trace mode 'head' continually increases. However in snapshot + * mode 'head' is an offset within the buffer. Here 'old' and 'head' + * are adjusted to match the full trace case which expects that 'old' is + * always less than 'head'. + */ + if (wrapped) { + *old = *head; + *head += mm->len; + } else { + if (mm->mask) + *old &= mm->mask; + else + *old %= mm->len; + if (*old > *head) + *head += mm->len; + } + + pr_debug3("%s: wrap-around %sdetected, adjusted old head %zu adjusted new head %zu\n", + __func__, wrapped ? "" : "not ", (size_t)*old, (size_t)*head); + + return 0; + +out_err: + pr_err("%s: failed, error %d\n", __func__, err); + return err; +} + +static u64 intel_pt_reference(struct auxtrace_record *itr __maybe_unused) +{ + return rdtsc(); +} + +struct auxtrace_record *intel_pt_recording_init(int *err) +{ + struct perf_pmu *intel_pt_pmu = perf_pmu__find(INTEL_PT_PMU_NAME); + struct intel_pt_recording *ptr; + + if (!intel_pt_pmu) + return NULL; + + if (setenv("JITDUMP_USE_ARCH_TIMESTAMP", "1", 1)) { + *err = -errno; + return NULL; + } + + ptr = zalloc(sizeof(struct intel_pt_recording)); + if (!ptr) { + *err = -ENOMEM; + return NULL; + } + + ptr->intel_pt_pmu = intel_pt_pmu; + ptr->itr.pmu = intel_pt_pmu; + ptr->itr.recording_options = intel_pt_recording_options; + ptr->itr.info_priv_size = intel_pt_info_priv_size; + ptr->itr.info_fill = intel_pt_info_fill; + ptr->itr.free = intel_pt_recording_free; + ptr->itr.snapshot_start = intel_pt_snapshot_start; + ptr->itr.snapshot_finish = intel_pt_snapshot_finish; + ptr->itr.find_snapshot = intel_pt_find_snapshot; + ptr->itr.parse_snapshot_options = intel_pt_parse_snapshot_options; + ptr->itr.reference = intel_pt_reference; + ptr->itr.read_finish = auxtrace_record__read_finish; + /* + * Decoding starts at a PSB packet. Minimum PSB period is 2K so 4K + * should give at least 1 PSB per sample. + */ + ptr->itr.default_aux_sample_size = 4096; + return &ptr->itr; +} |