evlist.c 39.1 KB
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/*
 * Copyright (C) 2011, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
 *
 * Parts came from builtin-{top,stat,record}.c, see those files for further
 * copyright notes.
 *
 * Released under the GPL v2. (and only v2, not any later version)
 */
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#include "util.h"
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#include <api/fs/fs.h>
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#include <poll.h>
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#include "cpumap.h"
#include "thread_map.h"
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#include "target.h"
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#include "evlist.h"
#include "evsel.h"
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#include "debug.h"
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#include <unistd.h>
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#include "parse-events.h"
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#include "parse-options.h"
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#include <sys/mman.h>

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#include <linux/bitops.h>
#include <linux/hash.h>
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#include <linux/log2.h>
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static void perf_evlist__mmap_put(struct perf_evlist *evlist, int idx);
static void __perf_evlist__munmap(struct perf_evlist *evlist, int idx);

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#define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
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#define SID(e, x, y) xyarray__entry(e->sample_id, x, y)
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void perf_evlist__init(struct perf_evlist *evlist, struct cpu_map *cpus,
		       struct thread_map *threads)
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{
	int i;

	for (i = 0; i < PERF_EVLIST__HLIST_SIZE; ++i)
		INIT_HLIST_HEAD(&evlist->heads[i]);
	INIT_LIST_HEAD(&evlist->entries);
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	perf_evlist__set_maps(evlist, cpus, threads);
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	fdarray__init(&evlist->pollfd, 64);
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	evlist->workload.pid = -1;
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}

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struct perf_evlist *perf_evlist__new(void)
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{
	struct perf_evlist *evlist = zalloc(sizeof(*evlist));

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	if (evlist != NULL)
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		perf_evlist__init(evlist, NULL, NULL);
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	return evlist;
}

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struct perf_evlist *perf_evlist__new_default(void)
{
	struct perf_evlist *evlist = perf_evlist__new();

	if (evlist && perf_evlist__add_default(evlist)) {
		perf_evlist__delete(evlist);
		evlist = NULL;
	}

	return evlist;
}

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/**
 * perf_evlist__set_id_pos - set the positions of event ids.
 * @evlist: selected event list
 *
 * Events with compatible sample types all have the same id_pos
 * and is_pos.  For convenience, put a copy on evlist.
 */
void perf_evlist__set_id_pos(struct perf_evlist *evlist)
{
	struct perf_evsel *first = perf_evlist__first(evlist);

	evlist->id_pos = first->id_pos;
	evlist->is_pos = first->is_pos;
}

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static void perf_evlist__update_id_pos(struct perf_evlist *evlist)
{
	struct perf_evsel *evsel;

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	evlist__for_each(evlist, evsel)
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		perf_evsel__calc_id_pos(evsel);

	perf_evlist__set_id_pos(evlist);
}

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static void perf_evlist__purge(struct perf_evlist *evlist)
{
	struct perf_evsel *pos, *n;

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	evlist__for_each_safe(evlist, n, pos) {
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		list_del_init(&pos->node);
		perf_evsel__delete(pos);
	}

	evlist->nr_entries = 0;
}

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void perf_evlist__exit(struct perf_evlist *evlist)
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{
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	zfree(&evlist->mmap);
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	fdarray__exit(&evlist->pollfd);
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}

void perf_evlist__delete(struct perf_evlist *evlist)
{
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	perf_evlist__munmap(evlist);
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	perf_evlist__close(evlist);
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	cpu_map__put(evlist->cpus);
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	thread_map__put(evlist->threads);
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	evlist->cpus = NULL;
	evlist->threads = NULL;
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	perf_evlist__purge(evlist);
	perf_evlist__exit(evlist);
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	free(evlist);
}

void perf_evlist__add(struct perf_evlist *evlist, struct perf_evsel *entry)
{
	list_add_tail(&entry->node, &evlist->entries);
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	entry->idx = evlist->nr_entries;
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	entry->tracking = !entry->idx;
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	if (!evlist->nr_entries++)
		perf_evlist__set_id_pos(evlist);
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}

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void perf_evlist__splice_list_tail(struct perf_evlist *evlist,
				   struct list_head *list,
				   int nr_entries)
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{
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	bool set_id_pos = !evlist->nr_entries;

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	list_splice_tail(list, &evlist->entries);
	evlist->nr_entries += nr_entries;
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	if (set_id_pos)
		perf_evlist__set_id_pos(evlist);
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}

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void __perf_evlist__set_leader(struct list_head *list)
{
	struct perf_evsel *evsel, *leader;

	leader = list_entry(list->next, struct perf_evsel, node);
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	evsel = list_entry(list->prev, struct perf_evsel, node);

	leader->nr_members = evsel->idx - leader->idx + 1;
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	__evlist__for_each(list, evsel) {
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		evsel->leader = leader;
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	}
}

void perf_evlist__set_leader(struct perf_evlist *evlist)
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{
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	if (evlist->nr_entries) {
		evlist->nr_groups = evlist->nr_entries > 1 ? 1 : 0;
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		__perf_evlist__set_leader(&evlist->entries);
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	}
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}

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int perf_evlist__add_default(struct perf_evlist *evlist)
{
	struct perf_event_attr attr = {
		.type = PERF_TYPE_HARDWARE,
		.config = PERF_COUNT_HW_CPU_CYCLES,
	};
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	struct perf_evsel *evsel;

	event_attr_init(&attr);
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	evsel = perf_evsel__new(&attr);
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	if (evsel == NULL)
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		goto error;

	/* use strdup() because free(evsel) assumes name is allocated */
	evsel->name = strdup("cycles");
	if (!evsel->name)
		goto error_free;
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	perf_evlist__add(evlist, evsel);
	return 0;
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error_free:
	perf_evsel__delete(evsel);
error:
	return -ENOMEM;
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}
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static int perf_evlist__add_attrs(struct perf_evlist *evlist,
				  struct perf_event_attr *attrs, size_t nr_attrs)
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{
	struct perf_evsel *evsel, *n;
	LIST_HEAD(head);
	size_t i;

	for (i = 0; i < nr_attrs; i++) {
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		evsel = perf_evsel__new_idx(attrs + i, evlist->nr_entries + i);
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		if (evsel == NULL)
			goto out_delete_partial_list;
		list_add_tail(&evsel->node, &head);
	}

	perf_evlist__splice_list_tail(evlist, &head, nr_attrs);

	return 0;

out_delete_partial_list:
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	__evlist__for_each_safe(&head, n, evsel)
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		perf_evsel__delete(evsel);
	return -1;
}

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int __perf_evlist__add_default_attrs(struct perf_evlist *evlist,
				     struct perf_event_attr *attrs, size_t nr_attrs)
{
	size_t i;

	for (i = 0; i < nr_attrs; i++)
		event_attr_init(attrs + i);

	return perf_evlist__add_attrs(evlist, attrs, nr_attrs);
}

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struct perf_evsel *
perf_evlist__find_tracepoint_by_id(struct perf_evlist *evlist, int id)
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{
	struct perf_evsel *evsel;

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	evlist__for_each(evlist, evsel) {
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		if (evsel->attr.type   == PERF_TYPE_TRACEPOINT &&
		    (int)evsel->attr.config == id)
			return evsel;
	}

	return NULL;
}

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struct perf_evsel *
perf_evlist__find_tracepoint_by_name(struct perf_evlist *evlist,
				     const char *name)
{
	struct perf_evsel *evsel;

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	evlist__for_each(evlist, evsel) {
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		if ((evsel->attr.type == PERF_TYPE_TRACEPOINT) &&
		    (strcmp(evsel->name, name) == 0))
			return evsel;
	}

	return NULL;
}

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int perf_evlist__add_newtp(struct perf_evlist *evlist,
			   const char *sys, const char *name, void *handler)
{
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	struct perf_evsel *evsel = perf_evsel__newtp(sys, name);
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	if (evsel == NULL)
		return -1;

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	evsel->handler = handler;
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	perf_evlist__add(evlist, evsel);
	return 0;
}

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static int perf_evlist__nr_threads(struct perf_evlist *evlist,
				   struct perf_evsel *evsel)
{
	if (evsel->system_wide)
		return 1;
	else
		return thread_map__nr(evlist->threads);
}

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void perf_evlist__disable(struct perf_evlist *evlist)
{
	int cpu, thread;
	struct perf_evsel *pos;
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	int nr_cpus = cpu_map__nr(evlist->cpus);
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	int nr_threads;
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	for (cpu = 0; cpu < nr_cpus; cpu++) {
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		evlist__for_each(evlist, pos) {
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			if (!perf_evsel__is_group_leader(pos) || !pos->fd)
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				continue;
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			nr_threads = perf_evlist__nr_threads(evlist, pos);
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			for (thread = 0; thread < nr_threads; thread++)
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				ioctl(FD(pos, cpu, thread),
				      PERF_EVENT_IOC_DISABLE, 0);
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		}
	}
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	evlist->enabled = false;
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}

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void perf_evlist__enable(struct perf_evlist *evlist)
{
	int cpu, thread;
	struct perf_evsel *pos;
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	int nr_cpus = cpu_map__nr(evlist->cpus);
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	int nr_threads;
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	for (cpu = 0; cpu < nr_cpus; cpu++) {
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		evlist__for_each(evlist, pos) {
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			if (!perf_evsel__is_group_leader(pos) || !pos->fd)
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				continue;
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			nr_threads = perf_evlist__nr_threads(evlist, pos);
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			for (thread = 0; thread < nr_threads; thread++)
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				ioctl(FD(pos, cpu, thread),
				      PERF_EVENT_IOC_ENABLE, 0);
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		}
	}
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	evlist->enabled = true;
}

void perf_evlist__toggle_enable(struct perf_evlist *evlist)
{
	(evlist->enabled ? perf_evlist__disable : perf_evlist__enable)(evlist);
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}

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int perf_evlist__disable_event(struct perf_evlist *evlist,
			       struct perf_evsel *evsel)
{
	int cpu, thread, err;
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	int nr_cpus = cpu_map__nr(evlist->cpus);
	int nr_threads = perf_evlist__nr_threads(evlist, evsel);
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	if (!evsel->fd)
		return 0;

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	for (cpu = 0; cpu < nr_cpus; cpu++) {
		for (thread = 0; thread < nr_threads; thread++) {
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			err = ioctl(FD(evsel, cpu, thread),
				    PERF_EVENT_IOC_DISABLE, 0);
			if (err)
				return err;
		}
	}
	return 0;
}

int perf_evlist__enable_event(struct perf_evlist *evlist,
			      struct perf_evsel *evsel)
{
	int cpu, thread, err;
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	int nr_cpus = cpu_map__nr(evlist->cpus);
	int nr_threads = perf_evlist__nr_threads(evlist, evsel);
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	if (!evsel->fd)
		return -EINVAL;

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	for (cpu = 0; cpu < nr_cpus; cpu++) {
		for (thread = 0; thread < nr_threads; thread++) {
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			err = ioctl(FD(evsel, cpu, thread),
				    PERF_EVENT_IOC_ENABLE, 0);
			if (err)
				return err;
		}
	}
	return 0;
}

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static int perf_evlist__enable_event_cpu(struct perf_evlist *evlist,
					 struct perf_evsel *evsel, int cpu)
{
	int thread, err;
	int nr_threads = perf_evlist__nr_threads(evlist, evsel);

	if (!evsel->fd)
		return -EINVAL;

	for (thread = 0; thread < nr_threads; thread++) {
		err = ioctl(FD(evsel, cpu, thread),
			    PERF_EVENT_IOC_ENABLE, 0);
		if (err)
			return err;
	}
	return 0;
}

static int perf_evlist__enable_event_thread(struct perf_evlist *evlist,
					    struct perf_evsel *evsel,
					    int thread)
{
	int cpu, err;
	int nr_cpus = cpu_map__nr(evlist->cpus);

	if (!evsel->fd)
		return -EINVAL;

	for (cpu = 0; cpu < nr_cpus; cpu++) {
		err = ioctl(FD(evsel, cpu, thread), PERF_EVENT_IOC_ENABLE, 0);
		if (err)
			return err;
	}
	return 0;
}

int perf_evlist__enable_event_idx(struct perf_evlist *evlist,
				  struct perf_evsel *evsel, int idx)
{
	bool per_cpu_mmaps = !cpu_map__empty(evlist->cpus);

	if (per_cpu_mmaps)
		return perf_evlist__enable_event_cpu(evlist, evsel, idx);
	else
		return perf_evlist__enable_event_thread(evlist, evsel, idx);
}

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int perf_evlist__alloc_pollfd(struct perf_evlist *evlist)
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{
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	int nr_cpus = cpu_map__nr(evlist->cpus);
	int nr_threads = thread_map__nr(evlist->threads);
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	int nfds = 0;
	struct perf_evsel *evsel;

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	evlist__for_each(evlist, evsel) {
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		if (evsel->system_wide)
			nfds += nr_cpus;
		else
			nfds += nr_cpus * nr_threads;
	}

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	if (fdarray__available_entries(&evlist->pollfd) < nfds &&
	    fdarray__grow(&evlist->pollfd, nfds) < 0)
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		return -ENOMEM;

	return 0;
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}
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static int __perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd, int idx)
{
	int pos = fdarray__add(&evlist->pollfd, fd, POLLIN | POLLERR | POLLHUP);
	/*
	 * Save the idx so that when we filter out fds POLLHUP'ed we can
	 * close the associated evlist->mmap[] entry.
	 */
	if (pos >= 0) {
		evlist->pollfd.priv[pos].idx = idx;

		fcntl(fd, F_SETFL, O_NONBLOCK);
	}

	return pos;
}

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int perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd)
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{
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	return __perf_evlist__add_pollfd(evlist, fd, -1);
}

static void perf_evlist__munmap_filtered(struct fdarray *fda, int fd)
{
	struct perf_evlist *evlist = container_of(fda, struct perf_evlist, pollfd);
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	perf_evlist__mmap_put(evlist, fda->priv[fd].idx);
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}
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int perf_evlist__filter_pollfd(struct perf_evlist *evlist, short revents_and_mask)
{
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	return fdarray__filter(&evlist->pollfd, revents_and_mask,
			       perf_evlist__munmap_filtered);
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}

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int perf_evlist__poll(struct perf_evlist *evlist, int timeout)
{
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	return fdarray__poll(&evlist->pollfd, timeout);
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}

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static void perf_evlist__id_hash(struct perf_evlist *evlist,
				 struct perf_evsel *evsel,
				 int cpu, int thread, u64 id)
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{
	int hash;
	struct perf_sample_id *sid = SID(evsel, cpu, thread);

	sid->id = id;
	sid->evsel = evsel;
	hash = hash_64(sid->id, PERF_EVLIST__HLIST_BITS);
	hlist_add_head(&sid->node, &evlist->heads[hash]);
}

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void perf_evlist__id_add(struct perf_evlist *evlist, struct perf_evsel *evsel,
			 int cpu, int thread, u64 id)
{
	perf_evlist__id_hash(evlist, evsel, cpu, thread, id);
	evsel->id[evsel->ids++] = id;
}

static int perf_evlist__id_add_fd(struct perf_evlist *evlist,
				  struct perf_evsel *evsel,
				  int cpu, int thread, int fd)
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{
	u64 read_data[4] = { 0, };
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	int id_idx = 1; /* The first entry is the counter value */
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	u64 id;
	int ret;

	ret = ioctl(fd, PERF_EVENT_IOC_ID, &id);
	if (!ret)
		goto add;

	if (errno != ENOTTY)
		return -1;

	/* Legacy way to get event id.. All hail to old kernels! */
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	/*
	 * This way does not work with group format read, so bail
	 * out in that case.
	 */
	if (perf_evlist__read_format(evlist) & PERF_FORMAT_GROUP)
		return -1;

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	if (!(evsel->attr.read_format & PERF_FORMAT_ID) ||
	    read(fd, &read_data, sizeof(read_data)) == -1)
		return -1;

	if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
		++id_idx;
	if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
		++id_idx;

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	id = read_data[id_idx];

 add:
	perf_evlist__id_add(evlist, evsel, cpu, thread, id);
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	return 0;
}

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static void perf_evlist__set_sid_idx(struct perf_evlist *evlist,
				     struct perf_evsel *evsel, int idx, int cpu,
				     int thread)
{
	struct perf_sample_id *sid = SID(evsel, cpu, thread);
	sid->idx = idx;
	if (evlist->cpus && cpu >= 0)
		sid->cpu = evlist->cpus->map[cpu];
	else
		sid->cpu = -1;
	if (!evsel->system_wide && evlist->threads && thread >= 0)
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		sid->tid = thread_map__pid(evlist->threads, thread);
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	else
		sid->tid = -1;
}

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struct perf_sample_id *perf_evlist__id2sid(struct perf_evlist *evlist, u64 id)
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{
	struct hlist_head *head;
	struct perf_sample_id *sid;
	int hash;

	hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
	head = &evlist->heads[hash];

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	hlist_for_each_entry(sid, head, node)
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		if (sid->id == id)
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			return sid;

	return NULL;
}

struct perf_evsel *perf_evlist__id2evsel(struct perf_evlist *evlist, u64 id)
{
	struct perf_sample_id *sid;

	if (evlist->nr_entries == 1)
		return perf_evlist__first(evlist);

	sid = perf_evlist__id2sid(evlist, id);
	if (sid)
		return sid->evsel;
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	if (!perf_evlist__sample_id_all(evlist))
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		return perf_evlist__first(evlist);
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	return NULL;
}
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static int perf_evlist__event2id(struct perf_evlist *evlist,
				 union perf_event *event, u64 *id)
{
	const u64 *array = event->sample.array;
	ssize_t n;

	n = (event->header.size - sizeof(event->header)) >> 3;

	if (event->header.type == PERF_RECORD_SAMPLE) {
		if (evlist->id_pos >= n)
			return -1;
		*id = array[evlist->id_pos];
	} else {
		if (evlist->is_pos > n)
			return -1;
		n -= evlist->is_pos;
		*id = array[n];
	}
	return 0;
}

static struct perf_evsel *perf_evlist__event2evsel(struct perf_evlist *evlist,
						   union perf_event *event)
{
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	struct perf_evsel *first = perf_evlist__first(evlist);
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	struct hlist_head *head;
	struct perf_sample_id *sid;
	int hash;
	u64 id;

	if (evlist->nr_entries == 1)
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		return first;

	if (!first->attr.sample_id_all &&
	    event->header.type != PERF_RECORD_SAMPLE)
		return first;
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	if (perf_evlist__event2id(evlist, event, &id))
		return NULL;

	/* Synthesized events have an id of zero */
	if (!id)
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		return first;
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	hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
	head = &evlist->heads[hash];

	hlist_for_each_entry(sid, head, node) {
		if (sid->id == id)
			return sid->evsel;
	}
	return NULL;
}

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union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx)
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{
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	struct perf_mmap *md = &evlist->mmap[idx];
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	u64 head;
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	u64 old = md->prev;
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	unsigned char *data = md->base + page_size;
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	union perf_event *event = NULL;
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	/*
	 * Check if event was unmapped due to a POLLHUP/POLLERR.
	 */
	if (!atomic_read(&md->refcnt))
		return NULL;

	head = perf_mmap__read_head(md);
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	if (evlist->overwrite) {
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		/*
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		 * If we're further behind than half the buffer, there's a chance
		 * the writer will bite our tail and mess up the samples under us.
		 *
		 * If we somehow ended up ahead of the head, we got messed up.
		 *
		 * In either case, truncate and restart at head.
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		 */
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		int diff = head - old;
		if (diff > md->mask / 2 || diff < 0) {
			fprintf(stderr, "WARNING: failed to keep up with mmap data.\n");

			/*
			 * head points to a known good entry, start there.
			 */
			old = head;
		}
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	}

	if (old != head) {
		size_t size;

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		event = (union perf_event *)&data[old & md->mask];
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		size = event->header.size;

		/*
		 * Event straddles the mmap boundary -- header should always
		 * be inside due to u64 alignment of output.
		 */
		if ((old & md->mask) + size != ((old + size) & md->mask)) {
			unsigned int offset = old;
			unsigned int len = min(sizeof(*event), size), cpy;
691
			void *dst = md->event_copy;
692 693 694 695 696 697 698 699 700

			do {
				cpy = min(md->mask + 1 - (offset & md->mask), len);
				memcpy(dst, &data[offset & md->mask], cpy);
				offset += cpy;
				dst += cpy;
				len -= cpy;
			} while (len);

701
			event = (union perf_event *) md->event_copy;
702 703 704 705 706 707
		}

		old += size;
	}

	md->prev = old;
708

709 710
	return event;
}
711

712 713
static bool perf_mmap__empty(struct perf_mmap *md)
{
714
	return perf_mmap__read_head(md) == md->prev && !md->auxtrace_mmap.base;
715 716 717 718
}

static void perf_evlist__mmap_get(struct perf_evlist *evlist, int idx)
{
719
	atomic_inc(&evlist->mmap[idx].refcnt);
720 721 722 723
}

static void perf_evlist__mmap_put(struct perf_evlist *evlist, int idx)
{
724
	BUG_ON(atomic_read(&evlist->mmap[idx].refcnt) == 0);
725

726
	if (atomic_dec_and_test(&evlist->mmap[idx].refcnt))
727 728 729
		__perf_evlist__munmap(evlist, idx);
}

730 731
void perf_evlist__mmap_consume(struct perf_evlist *evlist, int idx)
{
732 733
	struct perf_mmap *md = &evlist->mmap[idx];

734
	if (!evlist->overwrite) {
735
		u64 old = md->prev;
736 737 738

		perf_mmap__write_tail(md, old);
	}
739

740
	if (atomic_read(&md->refcnt) == 1 && perf_mmap__empty(md))
741
		perf_evlist__mmap_put(evlist, idx);
742 743
}

744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771
int __weak auxtrace_mmap__mmap(struct auxtrace_mmap *mm __maybe_unused,
			       struct auxtrace_mmap_params *mp __maybe_unused,
			       void *userpg __maybe_unused,
			       int fd __maybe_unused)
{
	return 0;
}

void __weak auxtrace_mmap__munmap(struct auxtrace_mmap *mm __maybe_unused)
{
}

void __weak auxtrace_mmap_params__init(
			struct auxtrace_mmap_params *mp __maybe_unused,
			off_t auxtrace_offset __maybe_unused,
			unsigned int auxtrace_pages __maybe_unused,
			bool auxtrace_overwrite __maybe_unused)
{
}

void __weak auxtrace_mmap_params__set_idx(
			struct auxtrace_mmap_params *mp __maybe_unused,
			struct perf_evlist *evlist __maybe_unused,
			int idx __maybe_unused,
			bool per_cpu __maybe_unused)
{
}

772 773 774 775 776
static void __perf_evlist__munmap(struct perf_evlist *evlist, int idx)
{
	if (evlist->mmap[idx].base != NULL) {
		munmap(evlist->mmap[idx].base, evlist->mmap_len);
		evlist->mmap[idx].base = NULL;
777
		atomic_set(&evlist->mmap[idx].refcnt, 0);
778
	}
779
	auxtrace_mmap__munmap(&evlist->mmap[idx].auxtrace_mmap);
780 781
}

782
void perf_evlist__munmap(struct perf_evlist *evlist)
783
{
784
	int i;
785

786 787 788
	if (evlist->mmap == NULL)
		return;

789 790
	for (i = 0; i < evlist->nr_mmaps; i++)
		__perf_evlist__munmap(evlist, i);
791

792
	zfree(&evlist->mmap);
793 794
}

795
static int perf_evlist__alloc_mmap(struct perf_evlist *evlist)
796
{
797
	evlist->nr_mmaps = cpu_map__nr(evlist->cpus);
798
	if (cpu_map__empty(evlist->cpus))
799
		evlist->nr_mmaps = thread_map__nr(evlist->threads);
800
	evlist->mmap = zalloc(evlist->nr_mmaps * sizeof(struct perf_mmap));
801 802 803
	return evlist->mmap != NULL ? 0 : -ENOMEM;
}

804 805 806
struct mmap_params {
	int prot;
	int mask;
807
	struct auxtrace_mmap_params auxtrace_mp;
808 809 810 811
};

static int __perf_evlist__mmap(struct perf_evlist *evlist, int idx,
			       struct mmap_params *mp, int fd)
812
{
813 814 815 816 817 818 819 820 821 822 823 824 825
	/*
	 * The last one will be done at perf_evlist__mmap_consume(), so that we
	 * make sure we don't prevent tools from consuming every last event in
	 * the ring buffer.
	 *
	 * I.e. we can get the POLLHUP meaning that the fd doesn't exist
	 * anymore, but the last events for it are still in the ring buffer,
	 * waiting to be consumed.
	 *
	 * Tools can chose to ignore this at their own discretion, but the
	 * evlist layer can't just drop it when filtering events in
	 * perf_evlist__filter_pollfd().
	 */
826
	atomic_set(&evlist->mmap[idx].refcnt, 2);
827
	evlist->mmap[idx].prev = 0;
828 829
	evlist->mmap[idx].mask = mp->mask;
	evlist->mmap[idx].base = mmap(NULL, evlist->mmap_len, mp->prot,
830
				      MAP_SHARED, fd, 0);
831
	if (evlist->mmap[idx].base == MAP_FAILED) {
832 833
		pr_debug2("failed to mmap perf event ring buffer, error %d\n",
			  errno);
834
		evlist->mmap[idx].base = NULL;
835
		return -1;
836
	}
837

838 839 840 841
	if (auxtrace_mmap__mmap(&evlist->mmap[idx].auxtrace_mmap,
				&mp->auxtrace_mp, evlist->mmap[idx].base, fd))
		return -1;

842 843 844
	return 0;
}

845
static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx,
846 847
				       struct mmap_params *mp, int cpu,
				       int thread, int *output)
848 849
{
	struct perf_evsel *evsel;
850

851
	evlist__for_each(evlist, evsel) {
852 853 854 855 856 857
		int fd;

		if (evsel->system_wide && thread)
			continue;

		fd = FD(evsel, cpu, thread);
858 859 860

		if (*output == -1) {
			*output = fd;
861
			if (__perf_evlist__mmap(evlist, idx, mp, *output) < 0)
862 863 864 865
				return -1;
		} else {
			if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, *output) != 0)
				return -1;
866 867

			perf_evlist__mmap_get(evlist, idx);
868 869
		}

870 871 872 873 874 875 876 877 878
		/*
		 * The system_wide flag causes a selected event to be opened
		 * always without a pid.  Consequently it will never get a
		 * POLLHUP, but it is used for tracking in combination with
		 * other events, so it should not need to be polled anyway.
		 * Therefore don't add it for polling.
		 */
		if (!evsel->system_wide &&
		    __perf_evlist__add_pollfd(evlist, fd, idx) < 0) {
879
			perf_evlist__mmap_put(evlist, idx);
880
			return -1;
881
		}
882

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Adrian Hunter 已提交
883 884 885 886 887 888 889
		if (evsel->attr.read_format & PERF_FORMAT_ID) {
			if (perf_evlist__id_add_fd(evlist, evsel, cpu, thread,
						   fd) < 0)
				return -1;
			perf_evlist__set_sid_idx(evlist, evsel, idx, cpu,
						 thread);
		}
890 891 892 893 894
	}

	return 0;
}

895 896
static int perf_evlist__mmap_per_cpu(struct perf_evlist *evlist,
				     struct mmap_params *mp)
897
{
898
	int cpu, thread;
899 900
	int nr_cpus = cpu_map__nr(evlist->cpus);
	int nr_threads = thread_map__nr(evlist->threads);
901

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Adrian Hunter 已提交
902
	pr_debug2("perf event ring buffer mmapped per cpu\n");
903
	for (cpu = 0; cpu < nr_cpus; cpu++) {
904 905
		int output = -1;

906 907 908
		auxtrace_mmap_params__set_idx(&mp->auxtrace_mp, evlist, cpu,
					      true);

909
		for (thread = 0; thread < nr_threads; thread++) {
910 911
			if (perf_evlist__mmap_per_evsel(evlist, cpu, mp, cpu,
							thread, &output))
912
				goto out_unmap;
913 914 915 916 917 918
		}
	}

	return 0;

out_unmap:
919 920
	for (cpu = 0; cpu < nr_cpus; cpu++)
		__perf_evlist__munmap(evlist, cpu);
921 922 923
	return -1;
}

924 925
static int perf_evlist__mmap_per_thread(struct perf_evlist *evlist,
					struct mmap_params *mp)
926 927
{
	int thread;
928
	int nr_threads = thread_map__nr(evlist->threads);
929

A
Adrian Hunter 已提交
930
	pr_debug2("perf event ring buffer mmapped per thread\n");
931
	for (thread = 0; thread < nr_threads; thread++) {
932 933
		int output = -1;

934 935 936
		auxtrace_mmap_params__set_idx(&mp->auxtrace_mp, evlist, thread,
					      false);

937 938
		if (perf_evlist__mmap_per_evsel(evlist, thread, mp, 0, thread,
						&output))
939
			goto out_unmap;
940 941 942 943 944
	}

	return 0;

out_unmap:
945 946
	for (thread = 0; thread < nr_threads; thread++)
		__perf_evlist__munmap(evlist, thread);
947 948 949
	return -1;
}

950 951
static size_t perf_evlist__mmap_size(unsigned long pages)
{
952 953 954 955 956 957 958 959 960 961 962 963 964 965 966
	if (pages == UINT_MAX) {
		int max;

		if (sysctl__read_int("kernel/perf_event_mlock_kb", &max) < 0) {
			/*
			 * Pick a once upon a time good value, i.e. things look
			 * strange since we can't read a sysctl value, but lets not
			 * die yet...
			 */
			max = 512;
		} else {
			max -= (page_size / 1024);
		}

		pages = (max * 1024) / page_size;
967 968
		if (!is_power_of_2(pages))
			pages = rounddown_pow_of_two(pages);
969
	} else if (!is_power_of_2(pages))
970 971 972 973 974
		return 0;

	return (pages + 1) * page_size;
}

975 976
static long parse_pages_arg(const char *str, unsigned long min,
			    unsigned long max)
977
{
978
	unsigned long pages, val;
979 980 981 982 983 984 985
	static struct parse_tag tags[] = {
		{ .tag  = 'B', .mult = 1       },
		{ .tag  = 'K', .mult = 1 << 10 },
		{ .tag  = 'M', .mult = 1 << 20 },
		{ .tag  = 'G', .mult = 1 << 30 },
		{ .tag  = 0 },
	};
986

987
	if (str == NULL)
988
		return -EINVAL;
989

990
	val = parse_tag_value(str, tags);
991
	if (val != (unsigned long) -1) {
992 993 994 995 996 997
		/* we got file size value */
		pages = PERF_ALIGN(val, page_size) / page_size;
	} else {
		/* we got pages count value */
		char *eptr;
		pages = strtoul(str, &eptr, 10);
998 999
		if (*eptr != '\0')
			return -EINVAL;
1000 1001
	}

1002
	if (pages == 0 && min == 0) {
1003
		/* leave number of pages at 0 */
1004
	} else if (!is_power_of_2(pages)) {
1005
		/* round pages up to next power of 2 */
1006
		pages = roundup_pow_of_two(pages);
1007 1008
		if (!pages)
			return -EINVAL;
1009 1010
		pr_info("rounding mmap pages size to %lu bytes (%lu pages)\n",
			pages * page_size, pages);
1011 1012
	}

1013 1014 1015 1016 1017 1018
	if (pages > max)
		return -EINVAL;

	return pages;
}

1019
int __perf_evlist__parse_mmap_pages(unsigned int *mmap_pages, const char *str)
1020 1021 1022 1023
{
	unsigned long max = UINT_MAX;
	long pages;

A
Adrian Hunter 已提交
1024
	if (max > SIZE_MAX / page_size)
1025 1026 1027 1028 1029
		max = SIZE_MAX / page_size;

	pages = parse_pages_arg(str, 1, max);
	if (pages < 0) {
		pr_err("Invalid argument for --mmap_pages/-m\n");
1030 1031 1032 1033 1034 1035 1036
		return -1;
	}

	*mmap_pages = pages;
	return 0;
}

1037 1038 1039 1040 1041 1042
int perf_evlist__parse_mmap_pages(const struct option *opt, const char *str,
				  int unset __maybe_unused)
{
	return __perf_evlist__parse_mmap_pages(opt->value, str);
}

1043
/**
1044
 * perf_evlist__mmap_ex - Create mmaps to receive events.
1045 1046 1047
 * @evlist: list of events
 * @pages: map length in pages
 * @overwrite: overwrite older events?
1048 1049
 * @auxtrace_pages - auxtrace map length in pages
 * @auxtrace_overwrite - overwrite older auxtrace data?
1050
 *
1051 1052 1053
 * If @overwrite is %false the user needs to signal event consumption using
 * perf_mmap__write_tail().  Using perf_evlist__mmap_read() does this
 * automatically.
1054
 *
1055 1056 1057
 * Similarly, if @auxtrace_overwrite is %false the user needs to signal data
 * consumption using auxtrace_mmap__write_tail().
 *
1058
 * Return: %0 on success, negative error code otherwise.
1059
 */
1060 1061 1062
int perf_evlist__mmap_ex(struct perf_evlist *evlist, unsigned int pages,
			 bool overwrite, unsigned int auxtrace_pages,
			 bool auxtrace_overwrite)
1063
{
1064
	struct perf_evsel *evsel;
1065 1066
	const struct cpu_map *cpus = evlist->cpus;
	const struct thread_map *threads = evlist->threads;
1067 1068 1069
	struct mmap_params mp = {
		.prot = PROT_READ | (overwrite ? 0 : PROT_WRITE),
	};
1070

1071
	if (evlist->mmap == NULL && perf_evlist__alloc_mmap(evlist) < 0)
1072 1073
		return -ENOMEM;

1074
	if (evlist->pollfd.entries == NULL && perf_evlist__alloc_pollfd(evlist) < 0)
1075 1076 1077
		return -ENOMEM;

	evlist->overwrite = overwrite;
1078
	evlist->mmap_len = perf_evlist__mmap_size(pages);
1079
	pr_debug("mmap size %zuB\n", evlist->mmap_len);
1080
	mp.mask = evlist->mmap_len - page_size - 1;
1081

1082 1083 1084
	auxtrace_mmap_params__init(&mp.auxtrace_mp, evlist->mmap_len,
				   auxtrace_pages, auxtrace_overwrite);

1085
	evlist__for_each(evlist, evsel) {
1086
		if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
1087
		    evsel->sample_id == NULL &&
1088
		    perf_evsel__alloc_id(evsel, cpu_map__nr(cpus), threads->nr) < 0)
1089 1090 1091
			return -ENOMEM;
	}

1092
	if (cpu_map__empty(cpus))
1093
		return perf_evlist__mmap_per_thread(evlist, &mp);
1094

1095
	return perf_evlist__mmap_per_cpu(evlist, &mp);
1096
}
1097

1098 1099 1100 1101 1102 1103
int perf_evlist__mmap(struct perf_evlist *evlist, unsigned int pages,
		      bool overwrite)
{
	return perf_evlist__mmap_ex(evlist, pages, overwrite, 0, false);
}

1104
static int perf_evlist__propagate_maps(struct perf_evlist *evlist,
1105
				       bool has_user_cpus)
1106 1107 1108 1109 1110 1111 1112 1113
{
	struct perf_evsel *evsel;

	evlist__for_each(evlist, evsel) {
		/*
		 * We already have cpus for evsel (via PMU sysfs) so
		 * keep it, if there's no target cpu list defined.
		 */
1114
		if (evsel->cpus && has_user_cpus)
1115 1116
			cpu_map__put(evsel->cpus);

1117
		if (!evsel->cpus || has_user_cpus)
1118 1119
			evsel->cpus = cpu_map__get(evlist->cpus);

1120 1121
		evsel->threads = thread_map__get(evlist->threads);

1122 1123
		if ((evlist->cpus && !evsel->cpus) ||
		    (evlist->threads && !evsel->threads))
1124 1125 1126 1127 1128 1129
			return -ENOMEM;
	}

	return 0;
}

1130
int perf_evlist__create_maps(struct perf_evlist *evlist, struct target *target)
1131
{
1132 1133
	evlist->threads = thread_map__new_str(target->pid, target->tid,
					      target->uid);
1134 1135 1136 1137

	if (evlist->threads == NULL)
		return -1;

1138
	if (target__uses_dummy_map(target))
N
Namhyung Kim 已提交
1139
		evlist->cpus = cpu_map__dummy_new();
1140 1141
	else
		evlist->cpus = cpu_map__new(target->cpu_list);
1142 1143 1144 1145

	if (evlist->cpus == NULL)
		goto out_delete_threads;

1146
	return perf_evlist__propagate_maps(evlist, !!target->cpu_list);
1147 1148

out_delete_threads:
1149
	thread_map__put(evlist->threads);
1150
	evlist->threads = NULL;
1151 1152 1153
	return -1;
}

1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170
int perf_evlist__set_maps(struct perf_evlist *evlist,
			  struct cpu_map *cpus,
			  struct thread_map *threads)
{
	if (evlist->cpus)
		cpu_map__put(evlist->cpus);

	evlist->cpus = cpus;

	if (evlist->threads)
		thread_map__put(evlist->threads);

	evlist->threads = threads;

	return perf_evlist__propagate_maps(evlist, false);
}

1171
int perf_evlist__apply_filters(struct perf_evlist *evlist, struct perf_evsel **err_evsel)
1172 1173
{
	struct perf_evsel *evsel;
1174 1175
	int err = 0;
	const int ncpus = cpu_map__nr(evlist->cpus),
1176
		  nthreads = thread_map__nr(evlist->threads);
1177

1178
	evlist__for_each(evlist, evsel) {
1179
		if (evsel->filter == NULL)
1180
			continue;
1181

1182
		err = perf_evsel__apply_filter(evsel, ncpus, nthreads, evsel->filter);
1183 1184
		if (err) {
			*err_evsel = evsel;
1185
			break;
1186
		}
1187 1188
	}

1189 1190 1191 1192 1193 1194 1195 1196
	return err;
}

int perf_evlist__set_filter(struct perf_evlist *evlist, const char *filter)
{
	struct perf_evsel *evsel;
	int err = 0;

1197
	evlist__for_each(evlist, evsel) {
1198
		err = perf_evsel__set_filter(evsel, filter);
1199 1200 1201 1202 1203
		if (err)
			break;
	}

	return err;
1204
}
1205

1206
int perf_evlist__set_filter_pids(struct perf_evlist *evlist, size_t npids, pid_t *pids)
1207 1208
{
	char *filter;
1209 1210
	int ret = -1;
	size_t i;
1211

1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225
	for (i = 0; i < npids; ++i) {
		if (i == 0) {
			if (asprintf(&filter, "common_pid != %d", pids[i]) < 0)
				return -1;
		} else {
			char *tmp;

			if (asprintf(&tmp, "%s && common_pid != %d", filter, pids[i]) < 0)
				goto out_free;

			free(filter);
			filter = tmp;
		}
	}
1226 1227

	ret = perf_evlist__set_filter(evlist, filter);
1228
out_free:
1229 1230 1231 1232
	free(filter);
	return ret;
}

1233 1234 1235 1236 1237
int perf_evlist__set_filter_pid(struct perf_evlist *evlist, pid_t pid)
{
	return perf_evlist__set_filter_pids(evlist, 1, &pid);
}

1238
bool perf_evlist__valid_sample_type(struct perf_evlist *evlist)
1239
{
1240
	struct perf_evsel *pos;
1241

1242 1243 1244 1245 1246 1247
	if (evlist->nr_entries == 1)
		return true;

	if (evlist->id_pos < 0 || evlist->is_pos < 0)
		return false;

1248
	evlist__for_each(evlist, pos) {
1249 1250
		if (pos->id_pos != evlist->id_pos ||
		    pos->is_pos != evlist->is_pos)
1251
			return false;
1252 1253
	}

1254
	return true;
1255 1256
}

1257
u64 __perf_evlist__combined_sample_type(struct perf_evlist *evlist)
1258
{
1259 1260 1261 1262 1263
	struct perf_evsel *evsel;

	if (evlist->combined_sample_type)
		return evlist->combined_sample_type;

1264
	evlist__for_each(evlist, evsel)
1265 1266 1267 1268 1269 1270 1271 1272 1273
		evlist->combined_sample_type |= evsel->attr.sample_type;

	return evlist->combined_sample_type;
}

u64 perf_evlist__combined_sample_type(struct perf_evlist *evlist)
{
	evlist->combined_sample_type = 0;
	return __perf_evlist__combined_sample_type(evlist);
1274 1275
}

1276 1277 1278 1279 1280 1281 1282 1283 1284 1285
u64 perf_evlist__combined_branch_type(struct perf_evlist *evlist)
{
	struct perf_evsel *evsel;
	u64 branch_type = 0;

	evlist__for_each(evlist, evsel)
		branch_type |= evsel->attr.branch_sample_type;
	return branch_type;
}

1286 1287 1288 1289 1290 1291
bool perf_evlist__valid_read_format(struct perf_evlist *evlist)
{
	struct perf_evsel *first = perf_evlist__first(evlist), *pos = first;
	u64 read_format = first->attr.read_format;
	u64 sample_type = first->attr.sample_type;

1292
	evlist__for_each(evlist, pos) {
1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311
		if (read_format != pos->attr.read_format)
			return false;
	}

	/* PERF_SAMPLE_READ imples PERF_FORMAT_ID. */
	if ((sample_type & PERF_SAMPLE_READ) &&
	    !(read_format & PERF_FORMAT_ID)) {
		return false;
	}

	return true;
}

u64 perf_evlist__read_format(struct perf_evlist *evlist)
{
	struct perf_evsel *first = perf_evlist__first(evlist);
	return first->attr.read_format;
}

1312
u16 perf_evlist__id_hdr_size(struct perf_evlist *evlist)
1313
{
1314
	struct perf_evsel *first = perf_evlist__first(evlist);
1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337
	struct perf_sample *data;
	u64 sample_type;
	u16 size = 0;

	if (!first->attr.sample_id_all)
		goto out;

	sample_type = first->attr.sample_type;

	if (sample_type & PERF_SAMPLE_TID)
		size += sizeof(data->tid) * 2;

       if (sample_type & PERF_SAMPLE_TIME)
		size += sizeof(data->time);

	if (sample_type & PERF_SAMPLE_ID)
		size += sizeof(data->id);

	if (sample_type & PERF_SAMPLE_STREAM_ID)
		size += sizeof(data->stream_id);

	if (sample_type & PERF_SAMPLE_CPU)
		size += sizeof(data->cpu) * 2;
1338 1339 1340

	if (sample_type & PERF_SAMPLE_IDENTIFIER)
		size += sizeof(data->id);
1341 1342 1343 1344
out:
	return size;
}

1345
bool perf_evlist__valid_sample_id_all(struct perf_evlist *evlist)
1346
{
1347
	struct perf_evsel *first = perf_evlist__first(evlist), *pos = first;
1348

1349
	evlist__for_each_continue(evlist, pos) {
1350 1351
		if (first->attr.sample_id_all != pos->attr.sample_id_all)
			return false;
1352 1353
	}

1354 1355 1356
	return true;
}

1357
bool perf_evlist__sample_id_all(struct perf_evlist *evlist)
1358
{
1359
	struct perf_evsel *first = perf_evlist__first(evlist);
1360
	return first->attr.sample_id_all;
1361
}
1362 1363 1364 1365 1366 1367

void perf_evlist__set_selected(struct perf_evlist *evlist,
			       struct perf_evsel *evsel)
{
	evlist->selected = evsel;
}
1368

1369 1370 1371 1372 1373
void perf_evlist__close(struct perf_evlist *evlist)
{
	struct perf_evsel *evsel;
	int ncpus = cpu_map__nr(evlist->cpus);
	int nthreads = thread_map__nr(evlist->threads);
1374
	int n;
1375

1376 1377 1378 1379
	evlist__for_each_reverse(evlist, evsel) {
		n = evsel->cpus ? evsel->cpus->nr : ncpus;
		perf_evsel__close(evsel, n, nthreads);
	}
1380 1381
}

1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406
static int perf_evlist__create_syswide_maps(struct perf_evlist *evlist)
{
	int err = -ENOMEM;

	/*
	 * Try reading /sys/devices/system/cpu/online to get
	 * an all cpus map.
	 *
	 * FIXME: -ENOMEM is the best we can do here, the cpu_map
	 * code needs an overhaul to properly forward the
	 * error, and we may not want to do that fallback to a
	 * default cpu identity map :-\
	 */
	evlist->cpus = cpu_map__new(NULL);
	if (evlist->cpus == NULL)
		goto out;

	evlist->threads = thread_map__new_dummy();
	if (evlist->threads == NULL)
		goto out_free_cpus;

	err = 0;
out:
	return err;
out_free_cpus:
1407
	cpu_map__put(evlist->cpus);
1408 1409 1410 1411
	evlist->cpus = NULL;
	goto out;
}

1412
int perf_evlist__open(struct perf_evlist *evlist)
1413
{
1414
	struct perf_evsel *evsel;
1415
	int err;
1416

1417 1418 1419 1420 1421 1422 1423 1424 1425 1426
	/*
	 * Default: one fd per CPU, all threads, aka systemwide
	 * as sys_perf_event_open(cpu = -1, thread = -1) is EINVAL
	 */
	if (evlist->threads == NULL && evlist->cpus == NULL) {
		err = perf_evlist__create_syswide_maps(evlist);
		if (err < 0)
			goto out_err;
	}

1427 1428
	perf_evlist__update_id_pos(evlist);

1429
	evlist__for_each(evlist, evsel) {
1430
		err = perf_evsel__open(evsel, evlist->cpus, evlist->threads);
1431 1432 1433 1434 1435 1436
		if (err < 0)
			goto out_err;
	}

	return 0;
out_err:
1437
	perf_evlist__close(evlist);
1438
	errno = -err;
1439 1440
	return err;
}
1441

1442
int perf_evlist__prepare_workload(struct perf_evlist *evlist, struct target *target,
1443
				  const char *argv[], bool pipe_output,
1444
				  void (*exec_error)(int signo, siginfo_t *info, void *ucontext))
1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465
{
	int child_ready_pipe[2], go_pipe[2];
	char bf;

	if (pipe(child_ready_pipe) < 0) {
		perror("failed to create 'ready' pipe");
		return -1;
	}

	if (pipe(go_pipe) < 0) {
		perror("failed to create 'go' pipe");
		goto out_close_ready_pipe;
	}

	evlist->workload.pid = fork();
	if (evlist->workload.pid < 0) {
		perror("failed to fork");
		goto out_close_pipes;
	}

	if (!evlist->workload.pid) {
1466 1467
		int ret;

1468
		if (pipe_output)
1469 1470
			dup2(2, 1);

1471 1472
		signal(SIGTERM, SIG_DFL);

1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484
		close(child_ready_pipe[0]);
		close(go_pipe[1]);
		fcntl(go_pipe[0], F_SETFD, FD_CLOEXEC);

		/*
		 * Tell the parent we're ready to go
		 */
		close(child_ready_pipe[1]);

		/*
		 * Wait until the parent tells us to go.
		 */
1485 1486 1487 1488 1489 1490
		ret = read(go_pipe[0], &bf, 1);
		/*
		 * The parent will ask for the execvp() to be performed by
		 * writing exactly one byte, in workload.cork_fd, usually via
		 * perf_evlist__start_workload().
		 *
1491
		 * For cancelling the workload without actually running it,
1492 1493 1494 1495 1496 1497 1498 1499 1500
		 * the parent will just close workload.cork_fd, without writing
		 * anything, i.e. read will return zero and we just exit()
		 * here.
		 */
		if (ret != 1) {
			if (ret == -1)
				perror("unable to read pipe");
			exit(ret);
		}
1501 1502 1503

		execvp(argv[0], (char **)argv);

1504
		if (exec_error) {
1505 1506 1507 1508 1509 1510 1511
			union sigval val;

			val.sival_int = errno;
			if (sigqueue(getppid(), SIGUSR1, val))
				perror(argv[0]);
		} else
			perror(argv[0]);
1512 1513 1514
		exit(-1);
	}

1515 1516 1517 1518 1519 1520 1521 1522
	if (exec_error) {
		struct sigaction act = {
			.sa_flags     = SA_SIGINFO,
			.sa_sigaction = exec_error,
		};
		sigaction(SIGUSR1, &act, NULL);
	}

1523 1524 1525 1526 1527 1528
	if (target__none(target)) {
		if (evlist->threads == NULL) {
			fprintf(stderr, "FATAL: evlist->threads need to be set at this point (%s:%d).\n",
				__func__, __LINE__);
			goto out_close_pipes;
		}
1529
		thread_map__set_pid(evlist->threads, 0, evlist->workload.pid);
1530
	}
1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541

	close(child_ready_pipe[1]);
	close(go_pipe[0]);
	/*
	 * wait for child to settle
	 */
	if (read(child_ready_pipe[0], &bf, 1) == -1) {
		perror("unable to read pipe");
		goto out_close_pipes;
	}

1542
	fcntl(go_pipe[1], F_SETFD, FD_CLOEXEC);
1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558
	evlist->workload.cork_fd = go_pipe[1];
	close(child_ready_pipe[0]);
	return 0;

out_close_pipes:
	close(go_pipe[0]);
	close(go_pipe[1]);
out_close_ready_pipe:
	close(child_ready_pipe[0]);
	close(child_ready_pipe[1]);
	return -1;
}

int perf_evlist__start_workload(struct perf_evlist *evlist)
{
	if (evlist->workload.cork_fd > 0) {
1559
		char bf = 0;
1560
		int ret;
1561 1562 1563
		/*
		 * Remove the cork, let it rip!
		 */
1564 1565 1566 1567 1568 1569
		ret = write(evlist->workload.cork_fd, &bf, 1);
		if (ret < 0)
			perror("enable to write to pipe");

		close(evlist->workload.cork_fd);
		return ret;
1570 1571 1572 1573
	}

	return 0;
}
1574

1575
int perf_evlist__parse_sample(struct perf_evlist *evlist, union perf_event *event,
1576
			      struct perf_sample *sample)
1577
{
1578 1579 1580 1581
	struct perf_evsel *evsel = perf_evlist__event2evsel(evlist, event);

	if (!evsel)
		return -EFAULT;
1582
	return perf_evsel__parse_sample(evsel, event, sample);
1583
}
1584 1585 1586 1587 1588 1589

size_t perf_evlist__fprintf(struct perf_evlist *evlist, FILE *fp)
{
	struct perf_evsel *evsel;
	size_t printed = 0;

1590
	evlist__for_each(evlist, evsel) {
1591 1592 1593 1594
		printed += fprintf(fp, "%s%s", evsel->idx ? ", " : "",
				   perf_evsel__name(evsel));
	}

1595
	return printed + fprintf(fp, "\n");
1596
}
1597

1598 1599 1600 1601
int perf_evlist__strerror_open(struct perf_evlist *evlist __maybe_unused,
			       int err, char *buf, size_t size)
{
	int printed, value;
1602
	char sbuf[STRERR_BUFSIZE], *emsg = strerror_r(err, sbuf, sizeof(sbuf));
1603 1604 1605 1606 1607 1608 1609 1610

	switch (err) {
	case EACCES:
	case EPERM:
		printed = scnprintf(buf, size,
				    "Error:\t%s.\n"
				    "Hint:\tCheck /proc/sys/kernel/perf_event_paranoid setting.", emsg);

1611
		value = perf_event_paranoid();
1612 1613 1614 1615 1616 1617 1618 1619

		printed += scnprintf(buf + printed, size - printed, "\nHint:\t");

		if (value >= 2) {
			printed += scnprintf(buf + printed, size - printed,
					     "For your workloads it needs to be <= 1\nHint:\t");
		}
		printed += scnprintf(buf + printed, size - printed,
1620
				     "For system wide tracing it needs to be set to -1.\n");
1621 1622

		printed += scnprintf(buf + printed, size - printed,
1623 1624
				    "Hint:\tTry: 'sudo sh -c \"echo -1 > /proc/sys/kernel/perf_event_paranoid\"'\n"
				    "Hint:\tThe current value is %d.", value);
1625 1626 1627 1628 1629 1630 1631 1632
		break;
	default:
		scnprintf(buf, size, "%s", emsg);
		break;
	}

	return 0;
}
1633

1634 1635 1636
int perf_evlist__strerror_mmap(struct perf_evlist *evlist, int err, char *buf, size_t size)
{
	char sbuf[STRERR_BUFSIZE], *emsg = strerror_r(err, sbuf, sizeof(sbuf));
1637
	int pages_attempted = evlist->mmap_len / 1024, pages_max_per_user, printed = 0;
1638 1639 1640

	switch (err) {
	case EPERM:
1641
		sysctl__read_int("kernel/perf_event_mlock_kb", &pages_max_per_user);
1642 1643
		printed += scnprintf(buf + printed, size - printed,
				     "Error:\t%s.\n"
1644
				     "Hint:\tCheck /proc/sys/kernel/perf_event_mlock_kb (%d kB) setting.\n"
1645
				     "Hint:\tTried using %zd kB.\n",
1646
				     emsg, pages_max_per_user, pages_attempted);
1647 1648 1649 1650 1651 1652 1653 1654 1655

		if (pages_attempted >= pages_max_per_user) {
			printed += scnprintf(buf + printed, size - printed,
					     "Hint:\tTry 'sudo sh -c \"echo %d > /proc/sys/kernel/perf_event_mlock_kb\"', or\n",
					     pages_max_per_user + pages_attempted);
		}

		printed += scnprintf(buf + printed, size - printed,
				     "Hint:\tTry using a smaller -m/--mmap-pages value.");
1656 1657 1658 1659 1660 1661 1662 1663 1664
		break;
	default:
		scnprintf(buf, size, "%s", emsg);
		break;
	}

	return 0;
}

1665 1666 1667 1668 1669 1670 1671 1672 1673
void perf_evlist__to_front(struct perf_evlist *evlist,
			   struct perf_evsel *move_evsel)
{
	struct perf_evsel *evsel, *n;
	LIST_HEAD(move);

	if (move_evsel == perf_evlist__first(evlist))
		return;

1674
	evlist__for_each_safe(evlist, n, evsel) {
1675 1676 1677 1678 1679 1680
		if (evsel->leader == move_evsel->leader)
			list_move_tail(&evsel->node, &move);
	}

	list_splice(&move, &evlist->entries);
}
1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696

void perf_evlist__set_tracking_event(struct perf_evlist *evlist,
				     struct perf_evsel *tracking_evsel)
{
	struct perf_evsel *evsel;

	if (tracking_evsel->tracking)
		return;

	evlist__for_each(evlist, evsel) {
		if (evsel != tracking_evsel)
			evsel->tracking = false;
	}

	tracking_evsel->tracking = true;
}