| /* |
| * intel-bts.c: Intel Processor Trace support |
| * Copyright (c) 2013-2015, Intel Corporation. |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms and conditions of the GNU General Public License, |
| * version 2, as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope 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. |
| * |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/types.h> |
| #include <linux/bitops.h> |
| #include <linux/log2.h> |
| |
| #include "../../util/cpumap.h" |
| #include "../../util/evsel.h" |
| #include "../../util/evlist.h" |
| #include "../../util/session.h" |
| #include "../../util/util.h" |
| #include "../../util/pmu.h" |
| #include "../../util/debug.h" |
| #include "../../util/tsc.h" |
| #include "../../util/auxtrace.h" |
| #include "../../util/intel-bts.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_BTS_DFLT_SAMPLE_SIZE KiB(4) |
| |
| #define INTEL_BTS_MAX_SAMPLE_SIZE KiB(60) |
| |
| struct intel_bts_snapshot_ref { |
| void *ref_buf; |
| size_t ref_offset; |
| bool wrapped; |
| }; |
| |
| struct intel_bts_recording { |
| struct auxtrace_record itr; |
| struct perf_pmu *intel_bts_pmu; |
| struct perf_evlist *evlist; |
| bool snapshot_mode; |
| size_t snapshot_size; |
| int snapshot_ref_cnt; |
| struct intel_bts_snapshot_ref *snapshot_refs; |
| }; |
| |
| struct branch { |
| u64 from; |
| u64 to; |
| u64 misc; |
| }; |
| |
| static size_t |
| intel_bts_info_priv_size(struct auxtrace_record *itr __maybe_unused, |
| struct perf_evlist *evlist __maybe_unused) |
| { |
| return INTEL_BTS_AUXTRACE_PRIV_SIZE; |
| } |
| |
| static int intel_bts_info_fill(struct auxtrace_record *itr, |
| struct perf_session *session, |
| struct auxtrace_info_event *auxtrace_info, |
| size_t priv_size) |
| { |
| struct intel_bts_recording *btsr = |
| container_of(itr, struct intel_bts_recording, itr); |
| struct perf_pmu *intel_bts_pmu = btsr->intel_bts_pmu; |
| struct perf_event_mmap_page *pc; |
| struct perf_tsc_conversion tc = { .time_mult = 0, }; |
| bool cap_user_time_zero = false; |
| int err; |
| |
| if (priv_size != INTEL_BTS_AUXTRACE_PRIV_SIZE) |
| return -EINVAL; |
| |
| if (!session->evlist->nr_mmaps) |
| return -EINVAL; |
| |
| pc = session->evlist->mmap[0].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 BTS: TSC not available\n"); |
| } |
| |
| auxtrace_info->type = PERF_AUXTRACE_INTEL_BTS; |
| auxtrace_info->priv[INTEL_BTS_PMU_TYPE] = intel_bts_pmu->type; |
| auxtrace_info->priv[INTEL_BTS_TIME_SHIFT] = tc.time_shift; |
| auxtrace_info->priv[INTEL_BTS_TIME_MULT] = tc.time_mult; |
| auxtrace_info->priv[INTEL_BTS_TIME_ZERO] = tc.time_zero; |
| auxtrace_info->priv[INTEL_BTS_CAP_USER_TIME_ZERO] = cap_user_time_zero; |
| auxtrace_info->priv[INTEL_BTS_SNAPSHOT_MODE] = btsr->snapshot_mode; |
| |
| return 0; |
| } |
| |
| static int intel_bts_recording_options(struct auxtrace_record *itr, |
| struct perf_evlist *evlist, |
| struct record_opts *opts) |
| { |
| struct intel_bts_recording *btsr = |
| container_of(itr, struct intel_bts_recording, itr); |
| struct perf_pmu *intel_bts_pmu = btsr->intel_bts_pmu; |
| struct perf_evsel *evsel, *intel_bts_evsel = NULL; |
| const struct cpu_map *cpus = evlist->cpus; |
| bool privileged = geteuid() == 0 || perf_event_paranoid() < 0; |
| |
| btsr->evlist = evlist; |
| btsr->snapshot_mode = opts->auxtrace_snapshot_mode; |
| |
| evlist__for_each_entry(evlist, evsel) { |
| if (evsel->attr.type == intel_bts_pmu->type) { |
| if (intel_bts_evsel) { |
| pr_err("There may be only one " INTEL_BTS_PMU_NAME " event\n"); |
| return -EINVAL; |
| } |
| evsel->attr.freq = 0; |
| evsel->attr.sample_period = 1; |
| intel_bts_evsel = evsel; |
| opts->full_auxtrace = true; |
| } |
| } |
| |
| if (opts->auxtrace_snapshot_mode && !opts->full_auxtrace) { |
| pr_err("Snapshot mode (-S option) requires " INTEL_BTS_PMU_NAME " PMU event (-e " INTEL_BTS_PMU_NAME ")\n"); |
| return -EINVAL; |
| } |
| |
| if (!opts->full_auxtrace) |
| return 0; |
| |
| if (opts->full_auxtrace && !cpu_map__empty(cpus)) { |
| pr_err(INTEL_BTS_PMU_NAME " does not support per-cpu recording\n"); |
| return -EINVAL; |
| } |
| |
| /* Set default sizes for snapshot mode */ |
| if (opts->auxtrace_snapshot_mode) { |
| 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 BTS snapshot size: %zu\n", |
| opts->auxtrace_snapshot_size); |
| } |
| |
| /* 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) |
| 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 BTS: must be at least %zuKiB and a power of 2\n", |
| min_sz / 1024); |
| return -EINVAL; |
| } |
| } |
| |
| if (intel_bts_evsel) { |
| /* |
| * To obtain the auxtrace buffer file descriptor, the auxtrace event |
| * must come first. |
| */ |
| perf_evlist__to_front(evlist, intel_bts_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(intel_bts_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; |
| } |
| |
| return 0; |
| } |
| |
| static int intel_bts_parse_snapshot_options(struct auxtrace_record *itr, |
| struct record_opts *opts, |
| const char *str) |
| { |
| struct intel_bts_recording *btsr = |
| container_of(itr, struct intel_bts_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; |
| |
| btsr->snapshot_size = snapshot_size; |
| |
| return 0; |
| } |
| |
| static u64 intel_bts_reference(struct auxtrace_record *itr __maybe_unused) |
| { |
| return rdtsc(); |
| } |
| |
| static int intel_bts_alloc_snapshot_refs(struct intel_bts_recording *btsr, |
| int idx) |
| { |
| const size_t sz = sizeof(struct intel_bts_snapshot_ref); |
| int cnt = btsr->snapshot_ref_cnt, new_cnt = cnt * 2; |
| struct intel_bts_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, btsr->snapshot_refs, cnt * sz); |
| |
| btsr->snapshot_refs = refs; |
| btsr->snapshot_ref_cnt = new_cnt; |
| |
| return 0; |
| } |
| |
| static void intel_bts_free_snapshot_refs(struct intel_bts_recording *btsr) |
| { |
| int i; |
| |
| for (i = 0; i < btsr->snapshot_ref_cnt; i++) |
| zfree(&btsr->snapshot_refs[i].ref_buf); |
| zfree(&btsr->snapshot_refs); |
| } |
| |
| static void intel_bts_recording_free(struct auxtrace_record *itr) |
| { |
| struct intel_bts_recording *btsr = |
| container_of(itr, struct intel_bts_recording, itr); |
| |
| intel_bts_free_snapshot_refs(btsr); |
| free(btsr); |
| } |
| |
| static int intel_bts_snapshot_start(struct auxtrace_record *itr) |
| { |
| struct intel_bts_recording *btsr = |
| container_of(itr, struct intel_bts_recording, itr); |
| struct perf_evsel *evsel; |
| |
| evlist__for_each_entry(btsr->evlist, evsel) { |
| if (evsel->attr.type == btsr->intel_bts_pmu->type) |
| return perf_evsel__disable(evsel); |
| } |
| return -EINVAL; |
| } |
| |
| static int intel_bts_snapshot_finish(struct auxtrace_record *itr) |
| { |
| struct intel_bts_recording *btsr = |
| container_of(itr, struct intel_bts_recording, itr); |
| struct perf_evsel *evsel; |
| |
| evlist__for_each_entry(btsr->evlist, evsel) { |
| if (evsel->attr.type == btsr->intel_bts_pmu->type) |
| return perf_evsel__enable(evsel); |
| } |
| return -EINVAL; |
| } |
| |
| static bool intel_bts_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_bts_find_snapshot(struct auxtrace_record *itr, int idx, |
| struct auxtrace_mmap *mm, unsigned char *data, |
| u64 *head, u64 *old) |
| { |
| struct intel_bts_recording *btsr = |
| container_of(itr, struct intel_bts_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); |
| |
| if (idx >= btsr->snapshot_ref_cnt) { |
| err = intel_bts_alloc_snapshot_refs(btsr, idx); |
| if (err) |
| goto out_err; |
| } |
| |
| wrapped = btsr->snapshot_refs[idx].wrapped; |
| if (!wrapped && intel_bts_first_wrap((u64 *)data, mm->len)) { |
| btsr->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 int intel_bts_read_finish(struct auxtrace_record *itr, int idx) |
| { |
| struct intel_bts_recording *btsr = |
| container_of(itr, struct intel_bts_recording, itr); |
| struct perf_evsel *evsel; |
| |
| evlist__for_each_entry(btsr->evlist, evsel) { |
| if (evsel->attr.type == btsr->intel_bts_pmu->type) |
| return perf_evlist__enable_event_idx(btsr->evlist, |
| evsel, idx); |
| } |
| return -EINVAL; |
| } |
| |
| struct auxtrace_record *intel_bts_recording_init(int *err) |
| { |
| struct perf_pmu *intel_bts_pmu = perf_pmu__find(INTEL_BTS_PMU_NAME); |
| struct intel_bts_recording *btsr; |
| |
| if (!intel_bts_pmu) |
| return NULL; |
| |
| if (setenv("JITDUMP_USE_ARCH_TIMESTAMP", "1", 1)) { |
| *err = -errno; |
| return NULL; |
| } |
| |
| btsr = zalloc(sizeof(struct intel_bts_recording)); |
| if (!btsr) { |
| *err = -ENOMEM; |
| return NULL; |
| } |
| |
| btsr->intel_bts_pmu = intel_bts_pmu; |
| btsr->itr.recording_options = intel_bts_recording_options; |
| btsr->itr.info_priv_size = intel_bts_info_priv_size; |
| btsr->itr.info_fill = intel_bts_info_fill; |
| btsr->itr.free = intel_bts_recording_free; |
| btsr->itr.snapshot_start = intel_bts_snapshot_start; |
| btsr->itr.snapshot_finish = intel_bts_snapshot_finish; |
| btsr->itr.find_snapshot = intel_bts_find_snapshot; |
| btsr->itr.parse_snapshot_options = intel_bts_parse_snapshot_options; |
| btsr->itr.reference = intel_bts_reference; |
| btsr->itr.read_finish = intel_bts_read_finish; |
| btsr->itr.alignment = sizeof(struct branch); |
| return &btsr->itr; |
| } |