From 2c47db90ed71af9c12d5600dbcef864761d76b3d Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Tue, 4 Jun 2019 16:00:09 +0300 Subject: [PATCH] perf intel-pt: Add support for efficient time interval filtering Set up time ranges for efficient time interval filtering using the new "fast forward" facility. Because decoding is done in time order, intel_pt_time_filter() needs to look only at the next start or end timestamp - refer intel_pt_next_time(). Signed-off-by: Adrian Hunter Cc: Jin Yao Cc: Jiri Olsa Link: http://lkml.kernel.org/r/20190604130017.31207-12-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/intel-pt.c | 208 +++++++++++++++++++++++++++++++++++++ 1 file changed, 208 insertions(+) diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c index 3e3a01318b76..43ddc78a066e 100644 --- a/tools/perf/util/intel-pt.c +++ b/tools/perf/util/intel-pt.c @@ -42,6 +42,7 @@ #include "tsc.h" #include "intel-pt.h" #include "config.h" +#include "time-utils.h" #include "intel-pt-decoder/intel-pt-log.h" #include "intel-pt-decoder/intel-pt-decoder.h" @@ -50,6 +51,11 @@ #define MAX_TIMESTAMP (~0ULL) +struct range { + u64 start; + u64 end; +}; + struct intel_pt { struct auxtrace auxtrace; struct auxtrace_queues queues; @@ -118,6 +124,9 @@ struct intel_pt { char *filter; struct addr_filters filts; + + struct range *time_ranges; + unsigned int range_cnt; }; enum switch_state { @@ -154,6 +163,9 @@ struct intel_pt_queue { bool have_sample; u64 time; u64 timestamp; + u64 sel_timestamp; + bool sel_start; + unsigned int sel_idx; u32 flags; u16 insn_len; u64 last_insn_cnt; @@ -1007,6 +1019,23 @@ static void intel_pt_sample_flags(struct intel_pt_queue *ptq) ptq->flags |= PERF_IP_FLAG_TRACE_END; } +static void intel_pt_setup_time_range(struct intel_pt *pt, + struct intel_pt_queue *ptq) +{ + if (!pt->range_cnt) + return; + + ptq->sel_timestamp = pt->time_ranges[0].start; + ptq->sel_idx = 0; + + if (ptq->sel_timestamp) { + ptq->sel_start = true; + } else { + ptq->sel_timestamp = pt->time_ranges[0].end; + ptq->sel_start = false; + } +} + static int intel_pt_setup_queue(struct intel_pt *pt, struct auxtrace_queue *queue, unsigned int queue_nr) @@ -1031,6 +1060,8 @@ static int intel_pt_setup_queue(struct intel_pt *pt, ptq->step_through_buffers = true; ptq->sync_switch = pt->sync_switch; + + intel_pt_setup_time_range(pt, ptq); } if (!ptq->on_heap && @@ -1045,6 +1076,14 @@ static int intel_pt_setup_queue(struct intel_pt *pt, intel_pt_log("queue %u getting timestamp\n", queue_nr); intel_pt_log("queue %u decoding cpu %d pid %d tid %d\n", queue_nr, ptq->cpu, ptq->pid, ptq->tid); + + if (ptq->sel_start && ptq->sel_timestamp) { + ret = intel_pt_fast_forward(ptq->decoder, + ptq->sel_timestamp); + if (ret) + return ret; + } + while (1) { state = intel_pt_decode(ptq->decoder); if (state->err) { @@ -1064,6 +1103,9 @@ static int intel_pt_setup_queue(struct intel_pt *pt, queue_nr, ptq->timestamp); ptq->state = state; ptq->have_sample = true; + if (ptq->sel_start && ptq->sel_timestamp && + ptq->timestamp < ptq->sel_timestamp) + ptq->have_sample = false; intel_pt_sample_flags(ptq); ret = auxtrace_heap__add(&pt->heap, queue_nr, ptq->timestamp); if (ret) @@ -1750,10 +1792,83 @@ static void intel_pt_enable_sync_switch(struct intel_pt *pt) } } +/* + * To filter against time ranges, it is only necessary to look at the next start + * or end time. + */ +static bool intel_pt_next_time(struct intel_pt_queue *ptq) +{ + struct intel_pt *pt = ptq->pt; + + if (ptq->sel_start) { + /* Next time is an end time */ + ptq->sel_start = false; + ptq->sel_timestamp = pt->time_ranges[ptq->sel_idx].end; + return true; + } else if (ptq->sel_idx + 1 < pt->range_cnt) { + /* Next time is a start time */ + ptq->sel_start = true; + ptq->sel_idx += 1; + ptq->sel_timestamp = pt->time_ranges[ptq->sel_idx].start; + return true; + } + + /* No next time */ + return false; +} + +static int intel_pt_time_filter(struct intel_pt_queue *ptq, u64 *ff_timestamp) +{ + int err; + + while (1) { + if (ptq->sel_start) { + if (ptq->timestamp >= ptq->sel_timestamp) { + /* After start time, so consider next time */ + intel_pt_next_time(ptq); + if (!ptq->sel_timestamp) { + /* No end time */ + return 0; + } + /* Check against end time */ + continue; + } + /* Before start time, so fast forward */ + ptq->have_sample = false; + if (ptq->sel_timestamp > *ff_timestamp) { + if (ptq->sync_switch) { + intel_pt_next_tid(ptq->pt, ptq); + ptq->switch_state = INTEL_PT_SS_UNKNOWN; + } + *ff_timestamp = ptq->sel_timestamp; + err = intel_pt_fast_forward(ptq->decoder, + ptq->sel_timestamp); + if (err) + return err; + } + return 0; + } else if (ptq->timestamp > ptq->sel_timestamp) { + /* After end time, so consider next time */ + if (!intel_pt_next_time(ptq)) { + /* No next time range, so stop decoding */ + ptq->have_sample = false; + ptq->switch_state = INTEL_PT_SS_NOT_TRACING; + return 1; + } + /* Check against next start time */ + continue; + } else { + /* Before end time */ + return 0; + } + } +} + static int intel_pt_run_decoder(struct intel_pt_queue *ptq, u64 *timestamp) { const struct intel_pt_state *state = ptq->state; struct intel_pt *pt = ptq->pt; + u64 ff_timestamp = 0; int err; if (!pt->kernel_start) { @@ -1818,6 +1933,12 @@ static int intel_pt_run_decoder(struct intel_pt_queue *ptq, u64 *timestamp) ptq->timestamp = state->timestamp; } + if (ptq->sel_timestamp) { + err = intel_pt_time_filter(ptq, &ff_timestamp); + if (err) + return err; + } + if (!pt->timeless_decoding && ptq->timestamp >= *timestamp) { *timestamp = ptq->timestamp; return 0; @@ -2223,6 +2344,7 @@ static void intel_pt_free(struct perf_session *session) thread__put(pt->unknown_thread); addr_filters__exit(&pt->filts); zfree(&pt->filter); + zfree(&pt->time_ranges); free(pt); } @@ -2520,6 +2642,85 @@ static int intel_pt_perf_config(const char *var, const char *value, void *data) return 0; } +/* Find least TSC which converts to ns or later */ +static u64 intel_pt_tsc_start(u64 ns, struct intel_pt *pt) +{ + u64 tsc, tm; + + tsc = perf_time_to_tsc(ns, &pt->tc); + + while (1) { + tm = tsc_to_perf_time(tsc, &pt->tc); + if (tm < ns) + break; + tsc -= 1; + } + + while (tm < ns) + tm = tsc_to_perf_time(++tsc, &pt->tc); + + return tsc; +} + +/* Find greatest TSC which converts to ns or earlier */ +static u64 intel_pt_tsc_end(u64 ns, struct intel_pt *pt) +{ + u64 tsc, tm; + + tsc = perf_time_to_tsc(ns, &pt->tc); + + while (1) { + tm = tsc_to_perf_time(tsc, &pt->tc); + if (tm > ns) + break; + tsc += 1; + } + + while (tm > ns) + tm = tsc_to_perf_time(--tsc, &pt->tc); + + return tsc; +} + +static int intel_pt_setup_time_ranges(struct intel_pt *pt, + struct itrace_synth_opts *opts) +{ + struct perf_time_interval *p = opts->ptime_range; + int n = opts->range_num; + int i; + + if (!n || !p || pt->timeless_decoding) + return 0; + + pt->time_ranges = calloc(n, sizeof(struct range)); + if (!pt->time_ranges) + return -ENOMEM; + + pt->range_cnt = n; + + intel_pt_log("%s: %u range(s)\n", __func__, n); + + for (i = 0; i < n; i++) { + struct range *r = &pt->time_ranges[i]; + u64 ts = p[i].start; + u64 te = p[i].end; + + /* + * Take care to ensure the TSC range matches the perf-time range + * when converted back to perf-time. + */ + r->start = ts ? intel_pt_tsc_start(ts, pt) : 0; + r->end = te ? intel_pt_tsc_end(te, pt) : 0; + + intel_pt_log("range %d: perf time interval: %"PRIu64" to %"PRIu64"\n", + i, ts, te); + intel_pt_log("range %d: TSC time interval: %#"PRIx64" to %#"PRIx64"\n", + i, r->start, r->end); + } + + return 0; +} + static const char * const intel_pt_info_fmts[] = { [INTEL_PT_PMU_TYPE] = " PMU Type %"PRId64"\n", [INTEL_PT_TIME_SHIFT] = " Time Shift %"PRIu64"\n", @@ -2752,6 +2953,12 @@ int intel_pt_process_auxtrace_info(union perf_event *event, pt->cbr2khz = tsc_freq / pt->max_non_turbo_ratio / 1000; } + if (session->itrace_synth_opts) { + err = intel_pt_setup_time_ranges(pt, session->itrace_synth_opts); + if (err) + goto err_delete_thread; + } + if (pt->synth_opts.calls) pt->branches_filter |= PERF_IP_FLAG_CALL | PERF_IP_FLAG_ASYNC | PERF_IP_FLAG_TRACE_END; @@ -2792,6 +2999,7 @@ err_free_queues: err_free: addr_filters__exit(&pt->filts); zfree(&pt->filter); + zfree(&pt->time_ranges); free(pt); return err; } -- 2.30.2