6a11f92ef4
The following union: union { u64 val64; u32 val32[2]; } u; is used on more than one place in perf code and will be used more in upcomming patches. Adding union u64_swap to have it defined globaly so we dont need to redefine it all the time. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Tested-by: David Ahern <dsahern@gmail.com> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1337151548-2396-4-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
672 lines
14 KiB
C
672 lines
14 KiB
C
/*
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* Copyright (C) 2011, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
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*
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* Parts came from builtin-{top,stat,record}.c, see those files for further
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* copyright notes.
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*
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* Released under the GPL v2. (and only v2, not any later version)
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*/
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#include <byteswap.h>
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#include "asm/bug.h"
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#include "evsel.h"
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#include "evlist.h"
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#include "util.h"
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#include "cpumap.h"
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#include "thread_map.h"
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#include "target.h"
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#define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
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#define GROUP_FD(group_fd, cpu) (*(int *)xyarray__entry(group_fd, cpu, 0))
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int __perf_evsel__sample_size(u64 sample_type)
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{
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u64 mask = sample_type & PERF_SAMPLE_MASK;
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int size = 0;
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int i;
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for (i = 0; i < 64; i++) {
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if (mask & (1ULL << i))
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size++;
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}
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size *= sizeof(u64);
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return size;
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}
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void hists__init(struct hists *hists)
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{
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memset(hists, 0, sizeof(*hists));
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hists->entries_in_array[0] = hists->entries_in_array[1] = RB_ROOT;
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hists->entries_in = &hists->entries_in_array[0];
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hists->entries_collapsed = RB_ROOT;
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hists->entries = RB_ROOT;
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pthread_mutex_init(&hists->lock, NULL);
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}
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void perf_evsel__init(struct perf_evsel *evsel,
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struct perf_event_attr *attr, int idx)
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{
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evsel->idx = idx;
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evsel->attr = *attr;
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INIT_LIST_HEAD(&evsel->node);
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hists__init(&evsel->hists);
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}
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struct perf_evsel *perf_evsel__new(struct perf_event_attr *attr, int idx)
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{
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struct perf_evsel *evsel = zalloc(sizeof(*evsel));
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if (evsel != NULL)
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perf_evsel__init(evsel, attr, idx);
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return evsel;
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}
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void perf_evsel__config(struct perf_evsel *evsel, struct perf_record_opts *opts,
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struct perf_evsel *first)
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{
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struct perf_event_attr *attr = &evsel->attr;
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int track = !evsel->idx; /* only the first counter needs these */
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attr->disabled = 1;
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attr->sample_id_all = opts->sample_id_all_missing ? 0 : 1;
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attr->inherit = !opts->no_inherit;
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attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
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PERF_FORMAT_TOTAL_TIME_RUNNING |
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PERF_FORMAT_ID;
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attr->sample_type |= PERF_SAMPLE_IP | PERF_SAMPLE_TID;
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/*
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* We default some events to a 1 default interval. But keep
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* it a weak assumption overridable by the user.
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*/
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if (!attr->sample_period || (opts->user_freq != UINT_MAX &&
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opts->user_interval != ULLONG_MAX)) {
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if (opts->freq) {
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attr->sample_type |= PERF_SAMPLE_PERIOD;
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attr->freq = 1;
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attr->sample_freq = opts->freq;
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} else {
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attr->sample_period = opts->default_interval;
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}
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}
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if (opts->no_samples)
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attr->sample_freq = 0;
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if (opts->inherit_stat)
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attr->inherit_stat = 1;
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if (opts->sample_address) {
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attr->sample_type |= PERF_SAMPLE_ADDR;
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attr->mmap_data = track;
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}
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if (opts->call_graph)
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attr->sample_type |= PERF_SAMPLE_CALLCHAIN;
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if (perf_target__has_cpu(&opts->target))
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attr->sample_type |= PERF_SAMPLE_CPU;
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if (opts->period)
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attr->sample_type |= PERF_SAMPLE_PERIOD;
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if (!opts->sample_id_all_missing &&
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(opts->sample_time || !opts->no_inherit ||
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perf_target__has_cpu(&opts->target)))
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attr->sample_type |= PERF_SAMPLE_TIME;
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if (opts->raw_samples) {
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attr->sample_type |= PERF_SAMPLE_TIME;
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attr->sample_type |= PERF_SAMPLE_RAW;
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attr->sample_type |= PERF_SAMPLE_CPU;
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}
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if (opts->no_delay) {
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attr->watermark = 0;
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attr->wakeup_events = 1;
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}
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if (opts->branch_stack) {
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attr->sample_type |= PERF_SAMPLE_BRANCH_STACK;
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attr->branch_sample_type = opts->branch_stack;
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}
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attr->mmap = track;
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attr->comm = track;
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if (perf_target__none(&opts->target) &&
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(!opts->group || evsel == first)) {
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attr->enable_on_exec = 1;
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}
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}
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int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
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{
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int cpu, thread;
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evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
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if (evsel->fd) {
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for (cpu = 0; cpu < ncpus; cpu++) {
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for (thread = 0; thread < nthreads; thread++) {
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FD(evsel, cpu, thread) = -1;
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}
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}
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}
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return evsel->fd != NULL ? 0 : -ENOMEM;
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}
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int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
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{
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evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
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if (evsel->sample_id == NULL)
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return -ENOMEM;
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evsel->id = zalloc(ncpus * nthreads * sizeof(u64));
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if (evsel->id == NULL) {
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xyarray__delete(evsel->sample_id);
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evsel->sample_id = NULL;
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return -ENOMEM;
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}
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return 0;
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}
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int perf_evsel__alloc_counts(struct perf_evsel *evsel, int ncpus)
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{
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evsel->counts = zalloc((sizeof(*evsel->counts) +
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(ncpus * sizeof(struct perf_counts_values))));
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return evsel->counts != NULL ? 0 : -ENOMEM;
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}
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void perf_evsel__free_fd(struct perf_evsel *evsel)
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{
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xyarray__delete(evsel->fd);
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evsel->fd = NULL;
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}
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void perf_evsel__free_id(struct perf_evsel *evsel)
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{
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xyarray__delete(evsel->sample_id);
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evsel->sample_id = NULL;
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free(evsel->id);
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evsel->id = NULL;
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}
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void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
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{
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int cpu, thread;
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for (cpu = 0; cpu < ncpus; cpu++)
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for (thread = 0; thread < nthreads; ++thread) {
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close(FD(evsel, cpu, thread));
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FD(evsel, cpu, thread) = -1;
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}
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}
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void perf_evsel__exit(struct perf_evsel *evsel)
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{
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assert(list_empty(&evsel->node));
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xyarray__delete(evsel->fd);
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xyarray__delete(evsel->sample_id);
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free(evsel->id);
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}
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void perf_evsel__delete(struct perf_evsel *evsel)
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{
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perf_evsel__exit(evsel);
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close_cgroup(evsel->cgrp);
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free(evsel->name);
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free(evsel);
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}
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int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
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int cpu, int thread, bool scale)
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{
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struct perf_counts_values count;
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size_t nv = scale ? 3 : 1;
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if (FD(evsel, cpu, thread) < 0)
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return -EINVAL;
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if (evsel->counts == NULL && perf_evsel__alloc_counts(evsel, cpu + 1) < 0)
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return -ENOMEM;
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if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) < 0)
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return -errno;
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if (scale) {
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if (count.run == 0)
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count.val = 0;
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else if (count.run < count.ena)
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count.val = (u64)((double)count.val * count.ena / count.run + 0.5);
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} else
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count.ena = count.run = 0;
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evsel->counts->cpu[cpu] = count;
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return 0;
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}
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int __perf_evsel__read(struct perf_evsel *evsel,
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int ncpus, int nthreads, bool scale)
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{
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size_t nv = scale ? 3 : 1;
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int cpu, thread;
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struct perf_counts_values *aggr = &evsel->counts->aggr, count;
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aggr->val = aggr->ena = aggr->run = 0;
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for (cpu = 0; cpu < ncpus; cpu++) {
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for (thread = 0; thread < nthreads; thread++) {
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if (FD(evsel, cpu, thread) < 0)
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continue;
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if (readn(FD(evsel, cpu, thread),
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&count, nv * sizeof(u64)) < 0)
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return -errno;
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aggr->val += count.val;
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if (scale) {
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aggr->ena += count.ena;
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aggr->run += count.run;
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}
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}
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}
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evsel->counts->scaled = 0;
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if (scale) {
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if (aggr->run == 0) {
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evsel->counts->scaled = -1;
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aggr->val = 0;
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return 0;
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}
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if (aggr->run < aggr->ena) {
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evsel->counts->scaled = 1;
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aggr->val = (u64)((double)aggr->val * aggr->ena / aggr->run + 0.5);
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}
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} else
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aggr->ena = aggr->run = 0;
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return 0;
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}
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static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
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struct thread_map *threads, bool group,
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struct xyarray *group_fds)
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{
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int cpu, thread;
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unsigned long flags = 0;
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int pid = -1, err;
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if (evsel->fd == NULL &&
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perf_evsel__alloc_fd(evsel, cpus->nr, threads->nr) < 0)
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return -ENOMEM;
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if (evsel->cgrp) {
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flags = PERF_FLAG_PID_CGROUP;
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pid = evsel->cgrp->fd;
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}
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for (cpu = 0; cpu < cpus->nr; cpu++) {
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int group_fd = group_fds ? GROUP_FD(group_fds, cpu) : -1;
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for (thread = 0; thread < threads->nr; thread++) {
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if (!evsel->cgrp)
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pid = threads->map[thread];
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FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
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pid,
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cpus->map[cpu],
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group_fd, flags);
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if (FD(evsel, cpu, thread) < 0) {
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err = -errno;
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goto out_close;
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}
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if (group && group_fd == -1)
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group_fd = FD(evsel, cpu, thread);
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}
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}
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return 0;
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out_close:
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do {
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while (--thread >= 0) {
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close(FD(evsel, cpu, thread));
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FD(evsel, cpu, thread) = -1;
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}
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thread = threads->nr;
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} while (--cpu >= 0);
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return err;
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}
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void perf_evsel__close(struct perf_evsel *evsel, int ncpus, int nthreads)
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{
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if (evsel->fd == NULL)
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return;
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perf_evsel__close_fd(evsel, ncpus, nthreads);
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perf_evsel__free_fd(evsel);
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evsel->fd = NULL;
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}
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static struct {
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struct cpu_map map;
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int cpus[1];
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} empty_cpu_map = {
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.map.nr = 1,
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.cpus = { -1, },
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};
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static struct {
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struct thread_map map;
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int threads[1];
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} empty_thread_map = {
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.map.nr = 1,
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.threads = { -1, },
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};
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int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
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struct thread_map *threads, bool group,
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struct xyarray *group_fd)
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{
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if (cpus == NULL) {
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/* Work around old compiler warnings about strict aliasing */
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cpus = &empty_cpu_map.map;
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}
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if (threads == NULL)
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threads = &empty_thread_map.map;
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return __perf_evsel__open(evsel, cpus, threads, group, group_fd);
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}
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int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
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struct cpu_map *cpus, bool group,
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struct xyarray *group_fd)
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{
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return __perf_evsel__open(evsel, cpus, &empty_thread_map.map, group,
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group_fd);
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}
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int perf_evsel__open_per_thread(struct perf_evsel *evsel,
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struct thread_map *threads, bool group,
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struct xyarray *group_fd)
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{
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return __perf_evsel__open(evsel, &empty_cpu_map.map, threads, group,
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group_fd);
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}
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static int perf_event__parse_id_sample(const union perf_event *event, u64 type,
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struct perf_sample *sample)
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{
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const u64 *array = event->sample.array;
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array += ((event->header.size -
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sizeof(event->header)) / sizeof(u64)) - 1;
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if (type & PERF_SAMPLE_CPU) {
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u32 *p = (u32 *)array;
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sample->cpu = *p;
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array--;
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}
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if (type & PERF_SAMPLE_STREAM_ID) {
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sample->stream_id = *array;
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array--;
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}
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if (type & PERF_SAMPLE_ID) {
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sample->id = *array;
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array--;
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}
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if (type & PERF_SAMPLE_TIME) {
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sample->time = *array;
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array--;
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}
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if (type & PERF_SAMPLE_TID) {
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u32 *p = (u32 *)array;
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sample->pid = p[0];
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sample->tid = p[1];
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}
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return 0;
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}
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static bool sample_overlap(const union perf_event *event,
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const void *offset, u64 size)
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{
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const void *base = event;
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if (offset + size > base + event->header.size)
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return true;
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return false;
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}
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int perf_event__parse_sample(const union perf_event *event, u64 type,
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int sample_size, bool sample_id_all,
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struct perf_sample *data, bool swapped)
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{
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const u64 *array;
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/*
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* used for cross-endian analysis. See git commit 65014ab3
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* for why this goofiness is needed.
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*/
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union u64_swap u;
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memset(data, 0, sizeof(*data));
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data->cpu = data->pid = data->tid = -1;
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data->stream_id = data->id = data->time = -1ULL;
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data->period = 1;
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if (event->header.type != PERF_RECORD_SAMPLE) {
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if (!sample_id_all)
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return 0;
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return perf_event__parse_id_sample(event, type, data);
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}
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array = event->sample.array;
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if (sample_size + sizeof(event->header) > event->header.size)
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return -EFAULT;
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if (type & PERF_SAMPLE_IP) {
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data->ip = event->ip.ip;
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array++;
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}
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if (type & PERF_SAMPLE_TID) {
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u.val64 = *array;
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if (swapped) {
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/* undo swap of u64, then swap on individual u32s */
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u.val64 = bswap_64(u.val64);
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u.val32[0] = bswap_32(u.val32[0]);
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u.val32[1] = bswap_32(u.val32[1]);
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}
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data->pid = u.val32[0];
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data->tid = u.val32[1];
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array++;
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}
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if (type & PERF_SAMPLE_TIME) {
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data->time = *array;
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array++;
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}
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data->addr = 0;
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if (type & PERF_SAMPLE_ADDR) {
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data->addr = *array;
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array++;
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}
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data->id = -1ULL;
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if (type & PERF_SAMPLE_ID) {
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data->id = *array;
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array++;
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}
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if (type & PERF_SAMPLE_STREAM_ID) {
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data->stream_id = *array;
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array++;
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}
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|
|
if (type & PERF_SAMPLE_CPU) {
|
|
|
|
u.val64 = *array;
|
|
if (swapped) {
|
|
/* undo swap of u64, then swap on individual u32s */
|
|
u.val64 = bswap_64(u.val64);
|
|
u.val32[0] = bswap_32(u.val32[0]);
|
|
}
|
|
|
|
data->cpu = u.val32[0];
|
|
array++;
|
|
}
|
|
|
|
if (type & PERF_SAMPLE_PERIOD) {
|
|
data->period = *array;
|
|
array++;
|
|
}
|
|
|
|
if (type & PERF_SAMPLE_READ) {
|
|
fprintf(stderr, "PERF_SAMPLE_READ is unsupported for now\n");
|
|
return -1;
|
|
}
|
|
|
|
if (type & PERF_SAMPLE_CALLCHAIN) {
|
|
if (sample_overlap(event, array, sizeof(data->callchain->nr)))
|
|
return -EFAULT;
|
|
|
|
data->callchain = (struct ip_callchain *)array;
|
|
|
|
if (sample_overlap(event, array, data->callchain->nr))
|
|
return -EFAULT;
|
|
|
|
array += 1 + data->callchain->nr;
|
|
}
|
|
|
|
if (type & PERF_SAMPLE_RAW) {
|
|
const u64 *pdata;
|
|
|
|
u.val64 = *array;
|
|
if (WARN_ONCE(swapped,
|
|
"Endianness of raw data not corrected!\n")) {
|
|
/* undo swap of u64, then swap on individual u32s */
|
|
u.val64 = bswap_64(u.val64);
|
|
u.val32[0] = bswap_32(u.val32[0]);
|
|
u.val32[1] = bswap_32(u.val32[1]);
|
|
}
|
|
|
|
if (sample_overlap(event, array, sizeof(u32)))
|
|
return -EFAULT;
|
|
|
|
data->raw_size = u.val32[0];
|
|
pdata = (void *) array + sizeof(u32);
|
|
|
|
if (sample_overlap(event, pdata, data->raw_size))
|
|
return -EFAULT;
|
|
|
|
data->raw_data = (void *) pdata;
|
|
|
|
array = (void *)array + data->raw_size + sizeof(u32);
|
|
}
|
|
|
|
if (type & PERF_SAMPLE_BRANCH_STACK) {
|
|
u64 sz;
|
|
|
|
data->branch_stack = (struct branch_stack *)array;
|
|
array++; /* nr */
|
|
|
|
sz = data->branch_stack->nr * sizeof(struct branch_entry);
|
|
sz /= sizeof(u64);
|
|
array += sz;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int perf_event__synthesize_sample(union perf_event *event, u64 type,
|
|
const struct perf_sample *sample,
|
|
bool swapped)
|
|
{
|
|
u64 *array;
|
|
|
|
/*
|
|
* used for cross-endian analysis. See git commit 65014ab3
|
|
* for why this goofiness is needed.
|
|
*/
|
|
union u64_swap u;
|
|
|
|
array = event->sample.array;
|
|
|
|
if (type & PERF_SAMPLE_IP) {
|
|
event->ip.ip = sample->ip;
|
|
array++;
|
|
}
|
|
|
|
if (type & PERF_SAMPLE_TID) {
|
|
u.val32[0] = sample->pid;
|
|
u.val32[1] = sample->tid;
|
|
if (swapped) {
|
|
/*
|
|
* Inverse of what is done in perf_event__parse_sample
|
|
*/
|
|
u.val32[0] = bswap_32(u.val32[0]);
|
|
u.val32[1] = bswap_32(u.val32[1]);
|
|
u.val64 = bswap_64(u.val64);
|
|
}
|
|
|
|
*array = u.val64;
|
|
array++;
|
|
}
|
|
|
|
if (type & PERF_SAMPLE_TIME) {
|
|
*array = sample->time;
|
|
array++;
|
|
}
|
|
|
|
if (type & PERF_SAMPLE_ADDR) {
|
|
*array = sample->addr;
|
|
array++;
|
|
}
|
|
|
|
if (type & PERF_SAMPLE_ID) {
|
|
*array = sample->id;
|
|
array++;
|
|
}
|
|
|
|
if (type & PERF_SAMPLE_STREAM_ID) {
|
|
*array = sample->stream_id;
|
|
array++;
|
|
}
|
|
|
|
if (type & PERF_SAMPLE_CPU) {
|
|
u.val32[0] = sample->cpu;
|
|
if (swapped) {
|
|
/*
|
|
* Inverse of what is done in perf_event__parse_sample
|
|
*/
|
|
u.val32[0] = bswap_32(u.val32[0]);
|
|
u.val64 = bswap_64(u.val64);
|
|
}
|
|
*array = u.val64;
|
|
array++;
|
|
}
|
|
|
|
if (type & PERF_SAMPLE_PERIOD) {
|
|
*array = sample->period;
|
|
array++;
|
|
}
|
|
|
|
return 0;
|
|
}
|