evsel.c 48.1 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 <byteswap.h>
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#include <linux/bitops.h>
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#include <lk/debugfs.h>
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#include <traceevent/event-parse.h>
#include <linux/hw_breakpoint.h>
#include <linux/perf_event.h>
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#include <sys/resource.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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#include "perf_regs.h"
A
Adrian Hunter 已提交
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#include "debug.h"
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static struct {
	bool sample_id_all;
	bool exclude_guest;
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	bool mmap2;
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} perf_missing_features;

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#define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))

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int __perf_evsel__sample_size(u64 sample_type)
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{
	u64 mask = sample_type & PERF_SAMPLE_MASK;
	int size = 0;
	int i;

	for (i = 0; i < 64; i++) {
		if (mask & (1ULL << i))
			size++;
	}

	size *= sizeof(u64);

	return size;
}

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/**
 * __perf_evsel__calc_id_pos - calculate id_pos.
 * @sample_type: sample type
 *
 * This function returns the position of the event id (PERF_SAMPLE_ID or
 * PERF_SAMPLE_IDENTIFIER) in a sample event i.e. in the array of struct
 * sample_event.
 */
static int __perf_evsel__calc_id_pos(u64 sample_type)
{
	int idx = 0;

	if (sample_type & PERF_SAMPLE_IDENTIFIER)
		return 0;

	if (!(sample_type & PERF_SAMPLE_ID))
		return -1;

	if (sample_type & PERF_SAMPLE_IP)
		idx += 1;

	if (sample_type & PERF_SAMPLE_TID)
		idx += 1;

	if (sample_type & PERF_SAMPLE_TIME)
		idx += 1;

	if (sample_type & PERF_SAMPLE_ADDR)
		idx += 1;

	return idx;
}

/**
 * __perf_evsel__calc_is_pos - calculate is_pos.
 * @sample_type: sample type
 *
 * This function returns the position (counting backwards) of the event id
 * (PERF_SAMPLE_ID or PERF_SAMPLE_IDENTIFIER) in a non-sample event i.e. if
 * sample_id_all is used there is an id sample appended to non-sample events.
 */
static int __perf_evsel__calc_is_pos(u64 sample_type)
{
	int idx = 1;

	if (sample_type & PERF_SAMPLE_IDENTIFIER)
		return 1;

	if (!(sample_type & PERF_SAMPLE_ID))
		return -1;

	if (sample_type & PERF_SAMPLE_CPU)
		idx += 1;

	if (sample_type & PERF_SAMPLE_STREAM_ID)
		idx += 1;

	return idx;
}

void perf_evsel__calc_id_pos(struct perf_evsel *evsel)
{
	evsel->id_pos = __perf_evsel__calc_id_pos(evsel->attr.sample_type);
	evsel->is_pos = __perf_evsel__calc_is_pos(evsel->attr.sample_type);
}

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void hists__init(struct hists *hists)
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{
	memset(hists, 0, sizeof(*hists));
	hists->entries_in_array[0] = hists->entries_in_array[1] = RB_ROOT;
	hists->entries_in = &hists->entries_in_array[0];
	hists->entries_collapsed = RB_ROOT;
	hists->entries = RB_ROOT;
	pthread_mutex_init(&hists->lock, NULL);
}

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void __perf_evsel__set_sample_bit(struct perf_evsel *evsel,
				  enum perf_event_sample_format bit)
{
	if (!(evsel->attr.sample_type & bit)) {
		evsel->attr.sample_type |= bit;
		evsel->sample_size += sizeof(u64);
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		perf_evsel__calc_id_pos(evsel);
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	}
}

void __perf_evsel__reset_sample_bit(struct perf_evsel *evsel,
				    enum perf_event_sample_format bit)
{
	if (evsel->attr.sample_type & bit) {
		evsel->attr.sample_type &= ~bit;
		evsel->sample_size -= sizeof(u64);
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		perf_evsel__calc_id_pos(evsel);
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	}
}

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void perf_evsel__set_sample_id(struct perf_evsel *evsel,
			       bool can_sample_identifier)
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{
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	if (can_sample_identifier) {
		perf_evsel__reset_sample_bit(evsel, ID);
		perf_evsel__set_sample_bit(evsel, IDENTIFIER);
	} else {
		perf_evsel__set_sample_bit(evsel, ID);
	}
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	evsel->attr.read_format |= PERF_FORMAT_ID;
}

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void perf_evsel__init(struct perf_evsel *evsel,
		      struct perf_event_attr *attr, int idx)
{
	evsel->idx	   = idx;
	evsel->attr	   = *attr;
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	evsel->leader	   = evsel;
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	INIT_LIST_HEAD(&evsel->node);
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	hists__init(&evsel->hists);
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	evsel->sample_size = __perf_evsel__sample_size(attr->sample_type);
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	perf_evsel__calc_id_pos(evsel);
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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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{
	struct perf_evsel *evsel = zalloc(sizeof(*evsel));

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	if (evsel != NULL)
		perf_evsel__init(evsel, attr, idx);
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	return evsel;
}

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struct event_format *event_format__new(const char *sys, const char *name)
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{
	int fd, n;
	char *filename;
	void *bf = NULL, *nbf;
	size_t size = 0, alloc_size = 0;
	struct event_format *format = NULL;

	if (asprintf(&filename, "%s/%s/%s/format", tracing_events_path, sys, name) < 0)
		goto out;

	fd = open(filename, O_RDONLY);
	if (fd < 0)
		goto out_free_filename;

	do {
		if (size == alloc_size) {
			alloc_size += BUFSIZ;
			nbf = realloc(bf, alloc_size);
			if (nbf == NULL)
				goto out_free_bf;
			bf = nbf;
		}

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		n = read(fd, bf + size, alloc_size - size);
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		if (n < 0)
			goto out_free_bf;
		size += n;
	} while (n > 0);

	pevent_parse_format(&format, bf, size, sys);

out_free_bf:
	free(bf);
	close(fd);
out_free_filename:
	free(filename);
out:
	return format;
}

struct perf_evsel *perf_evsel__newtp(const char *sys, const char *name, int idx)
{
	struct perf_evsel *evsel = zalloc(sizeof(*evsel));

	if (evsel != NULL) {
		struct perf_event_attr attr = {
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			.type	       = PERF_TYPE_TRACEPOINT,
			.sample_type   = (PERF_SAMPLE_RAW | PERF_SAMPLE_TIME |
					  PERF_SAMPLE_CPU | PERF_SAMPLE_PERIOD),
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		};

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		if (asprintf(&evsel->name, "%s:%s", sys, name) < 0)
			goto out_free;

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		evsel->tp_format = event_format__new(sys, name);
		if (evsel->tp_format == NULL)
			goto out_free;

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		event_attr_init(&attr);
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		attr.config = evsel->tp_format->id;
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		attr.sample_period = 1;
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		perf_evsel__init(evsel, &attr, idx);
	}

	return evsel;

out_free:
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	free(evsel->name);
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	free(evsel);
	return NULL;
}

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const char *perf_evsel__hw_names[PERF_COUNT_HW_MAX] = {
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	"cycles",
	"instructions",
	"cache-references",
	"cache-misses",
	"branches",
	"branch-misses",
	"bus-cycles",
	"stalled-cycles-frontend",
	"stalled-cycles-backend",
	"ref-cycles",
};

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static const char *__perf_evsel__hw_name(u64 config)
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{
	if (config < PERF_COUNT_HW_MAX && perf_evsel__hw_names[config])
		return perf_evsel__hw_names[config];

	return "unknown-hardware";
}

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static int perf_evsel__add_modifiers(struct perf_evsel *evsel, char *bf, size_t size)
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{
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	int colon = 0, r = 0;
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	struct perf_event_attr *attr = &evsel->attr;
	bool exclude_guest_default = false;

#define MOD_PRINT(context, mod)	do {					\
		if (!attr->exclude_##context) {				\
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			if (!colon) colon = ++r;			\
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			r += scnprintf(bf + r, size - r, "%c", mod);	\
		} } while(0)

	if (attr->exclude_kernel || attr->exclude_user || attr->exclude_hv) {
		MOD_PRINT(kernel, 'k');
		MOD_PRINT(user, 'u');
		MOD_PRINT(hv, 'h');
		exclude_guest_default = true;
	}

	if (attr->precise_ip) {
		if (!colon)
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			colon = ++r;
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		r += scnprintf(bf + r, size - r, "%.*s", attr->precise_ip, "ppp");
		exclude_guest_default = true;
	}

	if (attr->exclude_host || attr->exclude_guest == exclude_guest_default) {
		MOD_PRINT(host, 'H');
		MOD_PRINT(guest, 'G');
	}
#undef MOD_PRINT
	if (colon)
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		bf[colon - 1] = ':';
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	return r;
}

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static int perf_evsel__hw_name(struct perf_evsel *evsel, char *bf, size_t size)
{
	int r = scnprintf(bf, size, "%s", __perf_evsel__hw_name(evsel->attr.config));
	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
}

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const char *perf_evsel__sw_names[PERF_COUNT_SW_MAX] = {
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	"cpu-clock",
	"task-clock",
	"page-faults",
	"context-switches",
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	"cpu-migrations",
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	"minor-faults",
	"major-faults",
	"alignment-faults",
	"emulation-faults",
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	"dummy",
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};

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static const char *__perf_evsel__sw_name(u64 config)
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{
	if (config < PERF_COUNT_SW_MAX && perf_evsel__sw_names[config])
		return perf_evsel__sw_names[config];
	return "unknown-software";
}

static int perf_evsel__sw_name(struct perf_evsel *evsel, char *bf, size_t size)
{
	int r = scnprintf(bf, size, "%s", __perf_evsel__sw_name(evsel->attr.config));
	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
}

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static int __perf_evsel__bp_name(char *bf, size_t size, u64 addr, u64 type)
{
	int r;

	r = scnprintf(bf, size, "mem:0x%" PRIx64 ":", addr);

	if (type & HW_BREAKPOINT_R)
		r += scnprintf(bf + r, size - r, "r");

	if (type & HW_BREAKPOINT_W)
		r += scnprintf(bf + r, size - r, "w");

	if (type & HW_BREAKPOINT_X)
		r += scnprintf(bf + r, size - r, "x");

	return r;
}

static int perf_evsel__bp_name(struct perf_evsel *evsel, char *bf, size_t size)
{
	struct perf_event_attr *attr = &evsel->attr;
	int r = __perf_evsel__bp_name(bf, size, attr->bp_addr, attr->bp_type);
	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
}

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const char *perf_evsel__hw_cache[PERF_COUNT_HW_CACHE_MAX]
				[PERF_EVSEL__MAX_ALIASES] = {
 { "L1-dcache",	"l1-d",		"l1d",		"L1-data",		},
 { "L1-icache",	"l1-i",		"l1i",		"L1-instruction",	},
 { "LLC",	"L2",							},
 { "dTLB",	"d-tlb",	"Data-TLB",				},
 { "iTLB",	"i-tlb",	"Instruction-TLB",			},
 { "branch",	"branches",	"bpu",		"btb",		"bpc",	},
 { "node",								},
};

const char *perf_evsel__hw_cache_op[PERF_COUNT_HW_CACHE_OP_MAX]
				   [PERF_EVSEL__MAX_ALIASES] = {
 { "load",	"loads",	"read",					},
 { "store",	"stores",	"write",				},
 { "prefetch",	"prefetches",	"speculative-read", "speculative-load",	},
};

const char *perf_evsel__hw_cache_result[PERF_COUNT_HW_CACHE_RESULT_MAX]
				       [PERF_EVSEL__MAX_ALIASES] = {
 { "refs",	"Reference",	"ops",		"access",		},
 { "misses",	"miss",							},
};

#define C(x)		PERF_COUNT_HW_CACHE_##x
#define CACHE_READ	(1 << C(OP_READ))
#define CACHE_WRITE	(1 << C(OP_WRITE))
#define CACHE_PREFETCH	(1 << C(OP_PREFETCH))
#define COP(x)		(1 << x)

/*
 * cache operartion stat
 * L1I : Read and prefetch only
 * ITLB and BPU : Read-only
 */
static unsigned long perf_evsel__hw_cache_stat[C(MAX)] = {
 [C(L1D)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 [C(L1I)]	= (CACHE_READ | CACHE_PREFETCH),
 [C(LL)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 [C(DTLB)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
 [C(ITLB)]	= (CACHE_READ),
 [C(BPU)]	= (CACHE_READ),
 [C(NODE)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
};

bool perf_evsel__is_cache_op_valid(u8 type, u8 op)
{
	if (perf_evsel__hw_cache_stat[type] & COP(op))
		return true;	/* valid */
	else
		return false;	/* invalid */
}

int __perf_evsel__hw_cache_type_op_res_name(u8 type, u8 op, u8 result,
					    char *bf, size_t size)
{
	if (result) {
		return scnprintf(bf, size, "%s-%s-%s", perf_evsel__hw_cache[type][0],
				 perf_evsel__hw_cache_op[op][0],
				 perf_evsel__hw_cache_result[result][0]);
	}

	return scnprintf(bf, size, "%s-%s", perf_evsel__hw_cache[type][0],
			 perf_evsel__hw_cache_op[op][1]);
}

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static int __perf_evsel__hw_cache_name(u64 config, char *bf, size_t size)
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{
	u8 op, result, type = (config >>  0) & 0xff;
	const char *err = "unknown-ext-hardware-cache-type";

	if (type > PERF_COUNT_HW_CACHE_MAX)
		goto out_err;

	op = (config >>  8) & 0xff;
	err = "unknown-ext-hardware-cache-op";
	if (op > PERF_COUNT_HW_CACHE_OP_MAX)
		goto out_err;

	result = (config >> 16) & 0xff;
	err = "unknown-ext-hardware-cache-result";
	if (result > PERF_COUNT_HW_CACHE_RESULT_MAX)
		goto out_err;

	err = "invalid-cache";
	if (!perf_evsel__is_cache_op_valid(type, op))
		goto out_err;

	return __perf_evsel__hw_cache_type_op_res_name(type, op, result, bf, size);
out_err:
	return scnprintf(bf, size, "%s", err);
}

static int perf_evsel__hw_cache_name(struct perf_evsel *evsel, char *bf, size_t size)
{
	int ret = __perf_evsel__hw_cache_name(evsel->attr.config, bf, size);
	return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
}

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static int perf_evsel__raw_name(struct perf_evsel *evsel, char *bf, size_t size)
{
	int ret = scnprintf(bf, size, "raw 0x%" PRIx64, evsel->attr.config);
	return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
}

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const char *perf_evsel__name(struct perf_evsel *evsel)
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{
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	char bf[128];
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	if (evsel->name)
		return evsel->name;
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	switch (evsel->attr.type) {
	case PERF_TYPE_RAW:
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		perf_evsel__raw_name(evsel, bf, sizeof(bf));
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		break;

	case PERF_TYPE_HARDWARE:
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		perf_evsel__hw_name(evsel, bf, sizeof(bf));
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		break;
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	case PERF_TYPE_HW_CACHE:
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		perf_evsel__hw_cache_name(evsel, bf, sizeof(bf));
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		break;

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	case PERF_TYPE_SOFTWARE:
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		perf_evsel__sw_name(evsel, bf, sizeof(bf));
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		break;

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	case PERF_TYPE_TRACEPOINT:
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		scnprintf(bf, sizeof(bf), "%s", "unknown tracepoint");
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		break;

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	case PERF_TYPE_BREAKPOINT:
		perf_evsel__bp_name(evsel, bf, sizeof(bf));
		break;

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	default:
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		scnprintf(bf, sizeof(bf), "unknown attr type: %d",
			  evsel->attr.type);
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		break;
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	}

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	evsel->name = strdup(bf);

	return evsel->name ?: "unknown";
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}

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const char *perf_evsel__group_name(struct perf_evsel *evsel)
{
	return evsel->group_name ?: "anon group";
}

int perf_evsel__group_desc(struct perf_evsel *evsel, char *buf, size_t size)
{
	int ret;
	struct perf_evsel *pos;
	const char *group_name = perf_evsel__group_name(evsel);

	ret = scnprintf(buf, size, "%s", group_name);

	ret += scnprintf(buf + ret, size - ret, " { %s",
			 perf_evsel__name(evsel));

	for_each_group_member(pos, evsel)
		ret += scnprintf(buf + ret, size - ret, ", %s",
				 perf_evsel__name(pos));

	ret += scnprintf(buf + ret, size - ret, " }");

	return ret;
}

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/*
 * The enable_on_exec/disabled value strategy:
 *
 *  1) For any type of traced program:
 *    - all independent events and group leaders are disabled
 *    - all group members are enabled
 *
 *     Group members are ruled by group leaders. They need to
 *     be enabled, because the group scheduling relies on that.
 *
 *  2) For traced programs executed by perf:
 *     - all independent events and group leaders have
 *       enable_on_exec set
 *     - we don't specifically enable or disable any event during
 *       the record command
 *
 *     Independent events and group leaders are initially disabled
 *     and get enabled by exec. Group members are ruled by group
 *     leaders as stated in 1).
 *
 *  3) For traced programs attached by perf (pid/tid):
 *     - we specifically enable or disable all events during
 *       the record command
 *
 *     When attaching events to already running traced we
 *     enable/disable events specifically, as there's no
 *     initial traced exec call.
 */
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void perf_evsel__config(struct perf_evsel *evsel,
			struct perf_record_opts *opts)
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{
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	struct perf_evsel *leader = evsel->leader;
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	struct perf_event_attr *attr = &evsel->attr;
	int track = !evsel->idx; /* only the first counter needs these */

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	attr->sample_id_all = perf_missing_features.sample_id_all ? 0 : 1;
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	attr->inherit	    = !opts->no_inherit;

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	perf_evsel__set_sample_bit(evsel, IP);
	perf_evsel__set_sample_bit(evsel, TID);
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	if (evsel->sample_read) {
		perf_evsel__set_sample_bit(evsel, READ);

		/*
		 * We need ID even in case of single event, because
		 * PERF_SAMPLE_READ process ID specific data.
		 */
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		perf_evsel__set_sample_id(evsel, false);
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		/*
		 * Apply group format only if we belong to group
		 * with more than one members.
		 */
		if (leader->nr_members > 1) {
			attr->read_format |= PERF_FORMAT_GROUP;
			attr->inherit = 0;
		}
	}

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	/*
	 * We default some events to a 1 default interval. But keep
	 * it a weak assumption overridable by the user.
	 */
	if (!attr->sample_period || (opts->user_freq != UINT_MAX &&
				     opts->user_interval != ULLONG_MAX)) {
		if (opts->freq) {
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			perf_evsel__set_sample_bit(evsel, PERIOD);
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			attr->freq		= 1;
			attr->sample_freq	= opts->freq;
		} else {
			attr->sample_period = opts->default_interval;
		}
	}

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	/*
	 * Disable sampling for all group members other
	 * than leader in case leader 'leads' the sampling.
	 */
	if ((leader != evsel) && leader->sample_read) {
		attr->sample_freq   = 0;
		attr->sample_period = 0;
	}

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	if (opts->no_samples)
		attr->sample_freq = 0;

	if (opts->inherit_stat)
		attr->inherit_stat = 1;

	if (opts->sample_address) {
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		perf_evsel__set_sample_bit(evsel, ADDR);
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		attr->mmap_data = track;
	}

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	if (opts->call_graph) {
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		perf_evsel__set_sample_bit(evsel, CALLCHAIN);
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		if (opts->call_graph == CALLCHAIN_DWARF) {
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			perf_evsel__set_sample_bit(evsel, REGS_USER);
			perf_evsel__set_sample_bit(evsel, STACK_USER);
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			attr->sample_regs_user = PERF_REGS_MASK;
			attr->sample_stack_user = opts->stack_dump_size;
			attr->exclude_callchain_user = 1;
		}
	}

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	if (perf_target__has_cpu(&opts->target))
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		perf_evsel__set_sample_bit(evsel, CPU);
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	if (opts->period)
652
		perf_evsel__set_sample_bit(evsel, PERIOD);
653

654
	if (!perf_missing_features.sample_id_all &&
655
	    (opts->sample_time || !opts->no_inherit ||
656
	     perf_target__has_cpu(&opts->target)))
657
		perf_evsel__set_sample_bit(evsel, TIME);
658 659

	if (opts->raw_samples) {
660 661 662
		perf_evsel__set_sample_bit(evsel, TIME);
		perf_evsel__set_sample_bit(evsel, RAW);
		perf_evsel__set_sample_bit(evsel, CPU);
663 664
	}

665
	if (opts->sample_address)
666
		perf_evsel__set_sample_bit(evsel, DATA_SRC);
667

668 669 670 671
	if (opts->no_delay) {
		attr->watermark = 0;
		attr->wakeup_events = 1;
	}
672
	if (opts->branch_stack) {
673
		perf_evsel__set_sample_bit(evsel, BRANCH_STACK);
674 675
		attr->branch_sample_type = opts->branch_stack;
	}
676

677
	if (opts->sample_weight)
678
		perf_evsel__set_sample_bit(evsel, WEIGHT);
679

680 681
	attr->mmap  = track;
	attr->comm  = track;
682

683
	if (opts->sample_transaction)
684
		perf_evsel__set_sample_bit(evsel, TRANSACTION);
685

686 687 688 689 690 691
	/*
	 * XXX see the function comment above
	 *
	 * Disabling only independent events or group leaders,
	 * keeping group members enabled.
	 */
692
	if (perf_evsel__is_group_leader(evsel))
693 694 695 696 697 698
		attr->disabled = 1;

	/*
	 * Setting enable_on_exec for independent events and
	 * group leaders for traced executed by perf.
	 */
699
	if (perf_target__none(&opts->target) && perf_evsel__is_group_leader(evsel))
700 701 702
		attr->enable_on_exec = 1;
}

703 704
int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
{
705
	int cpu, thread;
706
	evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
707 708 709 710 711 712 713 714 715

	if (evsel->fd) {
		for (cpu = 0; cpu < ncpus; cpu++) {
			for (thread = 0; thread < nthreads; thread++) {
				FD(evsel, cpu, thread) = -1;
			}
		}
	}

716 717 718
	return evsel->fd != NULL ? 0 : -ENOMEM;
}

719 720
static int perf_evsel__run_ioctl(struct perf_evsel *evsel, int ncpus, int nthreads,
			  int ioc,  void *arg)
721 722 723 724 725 726
{
	int cpu, thread;

	for (cpu = 0; cpu < ncpus; cpu++) {
		for (thread = 0; thread < nthreads; thread++) {
			int fd = FD(evsel, cpu, thread),
727
			    err = ioctl(fd, ioc, arg);
728 729 730 731 732 733 734 735 736

			if (err)
				return err;
		}
	}

	return 0;
}

737 738 739 740 741 742 743 744 745 746 747 748 749 750 751
int perf_evsel__set_filter(struct perf_evsel *evsel, int ncpus, int nthreads,
			   const char *filter)
{
	return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
				     PERF_EVENT_IOC_SET_FILTER,
				     (void *)filter);
}

int perf_evsel__enable(struct perf_evsel *evsel, int ncpus, int nthreads)
{
	return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
				     PERF_EVENT_IOC_ENABLE,
				     0);
}

752 753
int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
{
754 755 756 757 758 759 760 761 762 763 764 765
	evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
	if (evsel->sample_id == NULL)
		return -ENOMEM;

	evsel->id = zalloc(ncpus * nthreads * sizeof(u64));
	if (evsel->id == NULL) {
		xyarray__delete(evsel->sample_id);
		evsel->sample_id = NULL;
		return -ENOMEM;
	}

	return 0;
766 767
}

768 769 770 771 772 773
void perf_evsel__reset_counts(struct perf_evsel *evsel, int ncpus)
{
	memset(evsel->counts, 0, (sizeof(*evsel->counts) +
				 (ncpus * sizeof(struct perf_counts_values))));
}

774 775 776 777 778 779 780
int perf_evsel__alloc_counts(struct perf_evsel *evsel, int ncpus)
{
	evsel->counts = zalloc((sizeof(*evsel->counts) +
				(ncpus * sizeof(struct perf_counts_values))));
	return evsel->counts != NULL ? 0 : -ENOMEM;
}

781 782 783 784 785 786
void perf_evsel__free_fd(struct perf_evsel *evsel)
{
	xyarray__delete(evsel->fd);
	evsel->fd = NULL;
}

787 788
void perf_evsel__free_id(struct perf_evsel *evsel)
{
789 790 791
	xyarray__delete(evsel->sample_id);
	evsel->sample_id = NULL;
	free(evsel->id);
792 793 794
	evsel->id = NULL;
}

795 796 797 798 799 800 801 802 803 804 805
void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
{
	int cpu, thread;

	for (cpu = 0; cpu < ncpus; cpu++)
		for (thread = 0; thread < nthreads; ++thread) {
			close(FD(evsel, cpu, thread));
			FD(evsel, cpu, thread) = -1;
		}
}

806 807 808 809 810
void perf_evsel__free_counts(struct perf_evsel *evsel)
{
	free(evsel->counts);
}

811
void perf_evsel__exit(struct perf_evsel *evsel)
812 813
{
	assert(list_empty(&evsel->node));
814 815
	perf_evsel__free_fd(evsel);
	perf_evsel__free_id(evsel);
816 817 818 819 820
}

void perf_evsel__delete(struct perf_evsel *evsel)
{
	perf_evsel__exit(evsel);
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821
	close_cgroup(evsel->cgrp);
822
	free(evsel->group_name);
823
	if (evsel->tp_format)
824
		pevent_free_format(evsel->tp_format);
825
	free(evsel->name);
826 827
	free(evsel);
}
828

829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850
static inline void compute_deltas(struct perf_evsel *evsel,
				  int cpu,
				  struct perf_counts_values *count)
{
	struct perf_counts_values tmp;

	if (!evsel->prev_raw_counts)
		return;

	if (cpu == -1) {
		tmp = evsel->prev_raw_counts->aggr;
		evsel->prev_raw_counts->aggr = *count;
	} else {
		tmp = evsel->prev_raw_counts->cpu[cpu];
		evsel->prev_raw_counts->cpu[cpu] = *count;
	}

	count->val = count->val - tmp.val;
	count->ena = count->ena - tmp.ena;
	count->run = count->run - tmp.run;
}

851 852 853 854 855 856 857 858 859
int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
			      int cpu, int thread, bool scale)
{
	struct perf_counts_values count;
	size_t nv = scale ? 3 : 1;

	if (FD(evsel, cpu, thread) < 0)
		return -EINVAL;

860 861 862
	if (evsel->counts == NULL && perf_evsel__alloc_counts(evsel, cpu + 1) < 0)
		return -ENOMEM;

863 864 865
	if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) < 0)
		return -errno;

866 867
	compute_deltas(evsel, cpu, &count);

868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886
	if (scale) {
		if (count.run == 0)
			count.val = 0;
		else if (count.run < count.ena)
			count.val = (u64)((double)count.val * count.ena / count.run + 0.5);
	} else
		count.ena = count.run = 0;

	evsel->counts->cpu[cpu] = count;
	return 0;
}

int __perf_evsel__read(struct perf_evsel *evsel,
		       int ncpus, int nthreads, bool scale)
{
	size_t nv = scale ? 3 : 1;
	int cpu, thread;
	struct perf_counts_values *aggr = &evsel->counts->aggr, count;

887
	aggr->val = aggr->ena = aggr->run = 0;
888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905

	for (cpu = 0; cpu < ncpus; cpu++) {
		for (thread = 0; thread < nthreads; thread++) {
			if (FD(evsel, cpu, thread) < 0)
				continue;

			if (readn(FD(evsel, cpu, thread),
				  &count, nv * sizeof(u64)) < 0)
				return -errno;

			aggr->val += count.val;
			if (scale) {
				aggr->ena += count.ena;
				aggr->run += count.run;
			}
		}
	}

906 907
	compute_deltas(evsel, -1, aggr);

908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924
	evsel->counts->scaled = 0;
	if (scale) {
		if (aggr->run == 0) {
			evsel->counts->scaled = -1;
			aggr->val = 0;
			return 0;
		}

		if (aggr->run < aggr->ena) {
			evsel->counts->scaled = 1;
			aggr->val = (u64)((double)aggr->val * aggr->ena / aggr->run + 0.5);
		}
	} else
		aggr->ena = aggr->run = 0;

	return 0;
}
925

926 927 928 929 930
static int get_group_fd(struct perf_evsel *evsel, int cpu, int thread)
{
	struct perf_evsel *leader = evsel->leader;
	int fd;

931
	if (perf_evsel__is_group_leader(evsel))
932 933 934 935 936 937 938 939 940 941 942 943 944 945
		return -1;

	/*
	 * Leader must be already processed/open,
	 * if not it's a bug.
	 */
	BUG_ON(!leader->fd);

	fd = FD(leader, cpu, thread);
	BUG_ON(fd == -1);

	return fd;
}

A
Adrian Hunter 已提交
946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987
#define __PRINT_ATTR(fmt, cast, field)  \
	fprintf(fp, "  %-19s "fmt"\n", #field, cast attr->field)

#define PRINT_ATTR_U32(field)  __PRINT_ATTR("%u" , , field)
#define PRINT_ATTR_X32(field)  __PRINT_ATTR("%#x", , field)
#define PRINT_ATTR_U64(field)  __PRINT_ATTR("%" PRIu64, (uint64_t), field)
#define PRINT_ATTR_X64(field)  __PRINT_ATTR("%#"PRIx64, (uint64_t), field)

#define PRINT_ATTR2N(name1, field1, name2, field2)	\
	fprintf(fp, "  %-19s %u    %-19s %u\n",		\
	name1, attr->field1, name2, attr->field2)

#define PRINT_ATTR2(field1, field2) \
	PRINT_ATTR2N(#field1, field1, #field2, field2)

static size_t perf_event_attr__fprintf(struct perf_event_attr *attr, FILE *fp)
{
	size_t ret = 0;

	ret += fprintf(fp, "%.60s\n", graph_dotted_line);
	ret += fprintf(fp, "perf_event_attr:\n");

	ret += PRINT_ATTR_U32(type);
	ret += PRINT_ATTR_U32(size);
	ret += PRINT_ATTR_X64(config);
	ret += PRINT_ATTR_U64(sample_period);
	ret += PRINT_ATTR_U64(sample_freq);
	ret += PRINT_ATTR_X64(sample_type);
	ret += PRINT_ATTR_X64(read_format);

	ret += PRINT_ATTR2(disabled, inherit);
	ret += PRINT_ATTR2(pinned, exclusive);
	ret += PRINT_ATTR2(exclude_user, exclude_kernel);
	ret += PRINT_ATTR2(exclude_hv, exclude_idle);
	ret += PRINT_ATTR2(mmap, comm);
	ret += PRINT_ATTR2(freq, inherit_stat);
	ret += PRINT_ATTR2(enable_on_exec, task);
	ret += PRINT_ATTR2(watermark, precise_ip);
	ret += PRINT_ATTR2(mmap_data, sample_id_all);
	ret += PRINT_ATTR2(exclude_host, exclude_guest);
	ret += PRINT_ATTR2N("excl.callchain_kern", exclude_callchain_kernel,
			    "excl.callchain_user", exclude_callchain_user);
988
	ret += PRINT_ATTR_U32(mmap2);
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989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005

	ret += PRINT_ATTR_U32(wakeup_events);
	ret += PRINT_ATTR_U32(wakeup_watermark);
	ret += PRINT_ATTR_X32(bp_type);
	ret += PRINT_ATTR_X64(bp_addr);
	ret += PRINT_ATTR_X64(config1);
	ret += PRINT_ATTR_U64(bp_len);
	ret += PRINT_ATTR_X64(config2);
	ret += PRINT_ATTR_X64(branch_sample_type);
	ret += PRINT_ATTR_X64(sample_regs_user);
	ret += PRINT_ATTR_U32(sample_stack_user);

	ret += fprintf(fp, "%.60s\n", graph_dotted_line);

	return ret;
}

1006
static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1007
			      struct thread_map *threads)
1008
{
1009
	int cpu, thread;
S
Stephane Eranian 已提交
1010
	unsigned long flags = 0;
1011
	int pid = -1, err;
1012
	enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;
1013

1014 1015
	if (evsel->fd == NULL &&
	    perf_evsel__alloc_fd(evsel, cpus->nr, threads->nr) < 0)
1016
		return -ENOMEM;
1017

S
Stephane Eranian 已提交
1018 1019 1020 1021 1022
	if (evsel->cgrp) {
		flags = PERF_FLAG_PID_CGROUP;
		pid = evsel->cgrp->fd;
	}

1023
fallback_missing_features:
1024 1025
	if (perf_missing_features.mmap2)
		evsel->attr.mmap2 = 0;
1026 1027 1028 1029 1030 1031
	if (perf_missing_features.exclude_guest)
		evsel->attr.exclude_guest = evsel->attr.exclude_host = 0;
retry_sample_id:
	if (perf_missing_features.sample_id_all)
		evsel->attr.sample_id_all = 0;

A
Adrian Hunter 已提交
1032 1033 1034
	if (verbose >= 2)
		perf_event_attr__fprintf(&evsel->attr, stderr);

1035
	for (cpu = 0; cpu < cpus->nr; cpu++) {
1036

1037
		for (thread = 0; thread < threads->nr; thread++) {
1038
			int group_fd;
S
Stephane Eranian 已提交
1039 1040 1041 1042

			if (!evsel->cgrp)
				pid = threads->map[thread];

1043
			group_fd = get_group_fd(evsel, cpu, thread);
1044
retry_open:
A
Adrian Hunter 已提交
1045 1046 1047
			pr_debug2("perf_event_open: pid %d  cpu %d  group_fd %d  flags %#lx\n",
				  pid, cpus->map[cpu], group_fd, flags);

1048
			FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
S
Stephane Eranian 已提交
1049
								     pid,
1050
								     cpus->map[cpu],
S
Stephane Eranian 已提交
1051
								     group_fd, flags);
1052 1053
			if (FD(evsel, cpu, thread) < 0) {
				err = -errno;
1054 1055
				pr_debug2("perf_event_open failed, error %d\n",
					  err);
1056
				goto try_fallback;
1057
			}
1058
			set_rlimit = NO_CHANGE;
1059
		}
1060 1061 1062 1063
	}

	return 0;

1064
try_fallback:
1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088
	/*
	 * perf stat needs between 5 and 22 fds per CPU. When we run out
	 * of them try to increase the limits.
	 */
	if (err == -EMFILE && set_rlimit < INCREASED_MAX) {
		struct rlimit l;
		int old_errno = errno;

		if (getrlimit(RLIMIT_NOFILE, &l) == 0) {
			if (set_rlimit == NO_CHANGE)
				l.rlim_cur = l.rlim_max;
			else {
				l.rlim_cur = l.rlim_max + 1000;
				l.rlim_max = l.rlim_cur;
			}
			if (setrlimit(RLIMIT_NOFILE, &l) == 0) {
				set_rlimit++;
				errno = old_errno;
				goto retry_open;
			}
		}
		errno = old_errno;
	}

1089 1090 1091
	if (err != -EINVAL || cpu > 0 || thread > 0)
		goto out_close;

1092 1093 1094 1095 1096
	if (!perf_missing_features.mmap2 && evsel->attr.mmap2) {
		perf_missing_features.mmap2 = true;
		goto fallback_missing_features;
	} else if (!perf_missing_features.exclude_guest &&
		   (evsel->attr.exclude_guest || evsel->attr.exclude_host)) {
1097 1098 1099 1100 1101 1102 1103
		perf_missing_features.exclude_guest = true;
		goto fallback_missing_features;
	} else if (!perf_missing_features.sample_id_all) {
		perf_missing_features.sample_id_all = true;
		goto retry_sample_id;
	}

1104
out_close:
1105 1106 1107 1108 1109 1110 1111
	do {
		while (--thread >= 0) {
			close(FD(evsel, cpu, thread));
			FD(evsel, cpu, thread) = -1;
		}
		thread = threads->nr;
	} while (--cpu >= 0);
1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122
	return err;
}

void perf_evsel__close(struct perf_evsel *evsel, int ncpus, int nthreads)
{
	if (evsel->fd == NULL)
		return;

	perf_evsel__close_fd(evsel, ncpus, nthreads);
	perf_evsel__free_fd(evsel);
	evsel->fd = NULL;
1123 1124
}

1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140
static struct {
	struct cpu_map map;
	int cpus[1];
} empty_cpu_map = {
	.map.nr	= 1,
	.cpus	= { -1, },
};

static struct {
	struct thread_map map;
	int threads[1];
} empty_thread_map = {
	.map.nr	 = 1,
	.threads = { -1, },
};

1141
int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1142
		     struct thread_map *threads)
1143
{
1144 1145 1146
	if (cpus == NULL) {
		/* Work around old compiler warnings about strict aliasing */
		cpus = &empty_cpu_map.map;
1147 1148
	}

1149 1150
	if (threads == NULL)
		threads = &empty_thread_map.map;
1151

1152
	return __perf_evsel__open(evsel, cpus, threads);
1153 1154
}

1155
int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
1156
			     struct cpu_map *cpus)
1157
{
1158
	return __perf_evsel__open(evsel, cpus, &empty_thread_map.map);
1159
}
1160

1161
int perf_evsel__open_per_thread(struct perf_evsel *evsel,
1162
				struct thread_map *threads)
1163
{
1164
	return __perf_evsel__open(evsel, &empty_cpu_map.map, threads);
1165
}
1166

1167 1168 1169
static int perf_evsel__parse_id_sample(const struct perf_evsel *evsel,
				       const union perf_event *event,
				       struct perf_sample *sample)
1170
{
1171
	u64 type = evsel->attr.sample_type;
1172
	const u64 *array = event->sample.array;
1173
	bool swapped = evsel->needs_swap;
1174
	union u64_swap u;
1175 1176 1177 1178

	array += ((event->header.size -
		   sizeof(event->header)) / sizeof(u64)) - 1;

1179 1180 1181 1182 1183
	if (type & PERF_SAMPLE_IDENTIFIER) {
		sample->id = *array;
		array--;
	}

1184
	if (type & PERF_SAMPLE_CPU) {
1185 1186 1187 1188 1189 1190 1191 1192
		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]);
		}

		sample->cpu = u.val32[0];
1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211
		array--;
	}

	if (type & PERF_SAMPLE_STREAM_ID) {
		sample->stream_id = *array;
		array--;
	}

	if (type & PERF_SAMPLE_ID) {
		sample->id = *array;
		array--;
	}

	if (type & PERF_SAMPLE_TIME) {
		sample->time = *array;
		array--;
	}

	if (type & PERF_SAMPLE_TID) {
1212 1213 1214 1215 1216 1217 1218 1219 1220 1221
		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]);
			u.val32[1] = bswap_32(u.val32[1]);
		}

		sample->pid = u.val32[0];
		sample->tid = u.val32[1];
1222
		array--;
1223 1224 1225 1226 1227
	}

	return 0;
}

1228 1229
static inline bool overflow(const void *endp, u16 max_size, const void *offset,
			    u64 size)
1230
{
1231 1232
	return size > max_size || offset + size > endp;
}
1233

1234 1235 1236 1237 1238
#define OVERFLOW_CHECK(offset, size, max_size)				\
	do {								\
		if (overflow(endp, (max_size), (offset), (size)))	\
			return -EFAULT;					\
	} while (0)
1239

1240 1241
#define OVERFLOW_CHECK_u64(offset) \
	OVERFLOW_CHECK(offset, sizeof(u64), sizeof(u64))
1242

1243
int perf_evsel__parse_sample(struct perf_evsel *evsel, union perf_event *event,
1244
			     struct perf_sample *data)
1245
{
1246
	u64 type = evsel->attr.sample_type;
1247
	bool swapped = evsel->needs_swap;
1248
	const u64 *array;
1249 1250 1251
	u16 max_size = event->header.size;
	const void *endp = (void *)event + max_size;
	u64 sz;
1252

1253 1254 1255 1256
	/*
	 * used for cross-endian analysis. See git commit 65014ab3
	 * for why this goofiness is needed.
	 */
1257
	union u64_swap u;
1258

1259
	memset(data, 0, sizeof(*data));
1260 1261
	data->cpu = data->pid = data->tid = -1;
	data->stream_id = data->id = data->time = -1ULL;
1262
	data->period = 1;
1263
	data->weight = 0;
1264 1265

	if (event->header.type != PERF_RECORD_SAMPLE) {
1266
		if (!evsel->attr.sample_id_all)
1267
			return 0;
1268
		return perf_evsel__parse_id_sample(evsel, event, data);
1269 1270 1271 1272
	}

	array = event->sample.array;

1273 1274 1275 1276 1277
	/*
	 * The evsel's sample_size is based on PERF_SAMPLE_MASK which includes
	 * up to PERF_SAMPLE_PERIOD.  After that overflow() must be used to
	 * check the format does not go past the end of the event.
	 */
1278
	if (evsel->sample_size + sizeof(event->header) > event->header.size)
1279 1280
		return -EFAULT;

1281 1282 1283 1284 1285 1286
	data->id = -1ULL;
	if (type & PERF_SAMPLE_IDENTIFIER) {
		data->id = *array;
		array++;
	}

1287
	if (type & PERF_SAMPLE_IP) {
1288
		data->ip = *array;
1289 1290 1291 1292
		array++;
	}

	if (type & PERF_SAMPLE_TID) {
1293 1294 1295 1296 1297 1298 1299 1300 1301 1302
		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]);
			u.val32[1] = bswap_32(u.val32[1]);
		}

		data->pid = u.val32[0];
		data->tid = u.val32[1];
1303 1304 1305 1306 1307 1308 1309 1310
		array++;
	}

	if (type & PERF_SAMPLE_TIME) {
		data->time = *array;
		array++;
	}

1311
	data->addr = 0;
1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327
	if (type & PERF_SAMPLE_ADDR) {
		data->addr = *array;
		array++;
	}

	if (type & PERF_SAMPLE_ID) {
		data->id = *array;
		array++;
	}

	if (type & PERF_SAMPLE_STREAM_ID) {
		data->stream_id = *array;
		array++;
	}

	if (type & PERF_SAMPLE_CPU) {
1328 1329 1330 1331 1332 1333 1334 1335 1336

		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];
1337 1338 1339 1340 1341 1342 1343 1344 1345
		array++;
	}

	if (type & PERF_SAMPLE_PERIOD) {
		data->period = *array;
		array++;
	}

	if (type & PERF_SAMPLE_READ) {
1346 1347
		u64 read_format = evsel->attr.read_format;

1348
		OVERFLOW_CHECK_u64(array);
1349 1350 1351 1352 1353 1354 1355 1356
		if (read_format & PERF_FORMAT_GROUP)
			data->read.group.nr = *array;
		else
			data->read.one.value = *array;

		array++;

		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1357
			OVERFLOW_CHECK_u64(array);
1358 1359 1360 1361 1362
			data->read.time_enabled = *array;
			array++;
		}

		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1363
			OVERFLOW_CHECK_u64(array);
1364 1365 1366 1367 1368 1369
			data->read.time_running = *array;
			array++;
		}

		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
		if (read_format & PERF_FORMAT_GROUP) {
1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380
			const u64 max_group_nr = UINT64_MAX /
					sizeof(struct sample_read_value);

			if (data->read.group.nr > max_group_nr)
				return -EFAULT;
			sz = data->read.group.nr *
			     sizeof(struct sample_read_value);
			OVERFLOW_CHECK(array, sz, max_size);
			data->read.group.values =
					(struct sample_read_value *)array;
			array = (void *)array + sz;
1381
		} else {
1382
			OVERFLOW_CHECK_u64(array);
1383 1384 1385
			data->read.one.id = *array;
			array++;
		}
1386 1387 1388
	}

	if (type & PERF_SAMPLE_CALLCHAIN) {
1389
		const u64 max_callchain_nr = UINT64_MAX / sizeof(u64);
1390

1391 1392 1393
		OVERFLOW_CHECK_u64(array);
		data->callchain = (struct ip_callchain *)array++;
		if (data->callchain->nr > max_callchain_nr)
1394
			return -EFAULT;
1395 1396 1397
		sz = data->callchain->nr * sizeof(u64);
		OVERFLOW_CHECK(array, sz, max_size);
		array = (void *)array + sz;
1398 1399 1400
	}

	if (type & PERF_SAMPLE_RAW) {
1401
		OVERFLOW_CHECK_u64(array);
1402 1403 1404 1405 1406 1407 1408 1409 1410
		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]);
		}
		data->raw_size = u.val32[0];
1411
		array = (void *)array + sizeof(u32);
1412

1413 1414 1415
		OVERFLOW_CHECK(array, data->raw_size, max_size);
		data->raw_data = (void *)array;
		array = (void *)array + data->raw_size;
1416 1417
	}

1418
	if (type & PERF_SAMPLE_BRANCH_STACK) {
1419 1420
		const u64 max_branch_nr = UINT64_MAX /
					  sizeof(struct branch_entry);
1421

1422 1423
		OVERFLOW_CHECK_u64(array);
		data->branch_stack = (struct branch_stack *)array++;
1424

1425 1426
		if (data->branch_stack->nr > max_branch_nr)
			return -EFAULT;
1427
		sz = data->branch_stack->nr * sizeof(struct branch_entry);
1428 1429
		OVERFLOW_CHECK(array, sz, max_size);
		array = (void *)array + sz;
1430
	}
1431 1432

	if (type & PERF_SAMPLE_REGS_USER) {
1433
		OVERFLOW_CHECK_u64(array);
1434 1435
		data->user_regs.abi = *array;
		array++;
1436

1437
		if (data->user_regs.abi) {
1438 1439 1440 1441
			u64 regs_user = evsel->attr.sample_regs_user;

			sz = hweight_long(regs_user) * sizeof(u64);
			OVERFLOW_CHECK(array, sz, max_size);
1442
			data->user_regs.regs = (u64 *)array;
1443
			array = (void *)array + sz;
1444 1445 1446 1447
		}
	}

	if (type & PERF_SAMPLE_STACK_USER) {
1448 1449
		OVERFLOW_CHECK_u64(array);
		sz = *array++;
1450 1451 1452 1453

		data->user_stack.offset = ((char *)(array - 1)
					  - (char *) event);

1454
		if (!sz) {
1455 1456
			data->user_stack.size = 0;
		} else {
1457
			OVERFLOW_CHECK(array, sz, max_size);
1458
			data->user_stack.data = (char *)array;
1459 1460
			array = (void *)array + sz;
			OVERFLOW_CHECK_u64(array);
1461
			data->user_stack.size = *array++;
1462 1463 1464
			if (WARN_ONCE(data->user_stack.size > sz,
				      "user stack dump failure\n"))
				return -EFAULT;
1465 1466 1467
		}
	}

1468 1469
	data->weight = 0;
	if (type & PERF_SAMPLE_WEIGHT) {
1470
		OVERFLOW_CHECK_u64(array);
1471 1472 1473 1474
		data->weight = *array;
		array++;
	}

1475 1476
	data->data_src = PERF_MEM_DATA_SRC_NONE;
	if (type & PERF_SAMPLE_DATA_SRC) {
1477
		OVERFLOW_CHECK_u64(array);
1478 1479 1480 1481
		data->data_src = *array;
		array++;
	}

1482 1483
	data->transaction = 0;
	if (type & PERF_SAMPLE_TRANSACTION) {
1484
		OVERFLOW_CHECK_u64(array);
1485 1486 1487 1488
		data->transaction = *array;
		array++;
	}

1489 1490
	return 0;
}
1491

1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580
size_t perf_event__sample_event_size(const struct perf_sample *sample, u64 type,
				     u64 sample_regs_user, u64 read_format)
{
	size_t sz, result = sizeof(struct sample_event);

	if (type & PERF_SAMPLE_IDENTIFIER)
		result += sizeof(u64);

	if (type & PERF_SAMPLE_IP)
		result += sizeof(u64);

	if (type & PERF_SAMPLE_TID)
		result += sizeof(u64);

	if (type & PERF_SAMPLE_TIME)
		result += sizeof(u64);

	if (type & PERF_SAMPLE_ADDR)
		result += sizeof(u64);

	if (type & PERF_SAMPLE_ID)
		result += sizeof(u64);

	if (type & PERF_SAMPLE_STREAM_ID)
		result += sizeof(u64);

	if (type & PERF_SAMPLE_CPU)
		result += sizeof(u64);

	if (type & PERF_SAMPLE_PERIOD)
		result += sizeof(u64);

	if (type & PERF_SAMPLE_READ) {
		result += sizeof(u64);
		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
			result += sizeof(u64);
		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
			result += sizeof(u64);
		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
		if (read_format & PERF_FORMAT_GROUP) {
			sz = sample->read.group.nr *
			     sizeof(struct sample_read_value);
			result += sz;
		} else {
			result += sizeof(u64);
		}
	}

	if (type & PERF_SAMPLE_CALLCHAIN) {
		sz = (sample->callchain->nr + 1) * sizeof(u64);
		result += sz;
	}

	if (type & PERF_SAMPLE_RAW) {
		result += sizeof(u32);
		result += sample->raw_size;
	}

	if (type & PERF_SAMPLE_BRANCH_STACK) {
		sz = sample->branch_stack->nr * sizeof(struct branch_entry);
		sz += sizeof(u64);
		result += sz;
	}

	if (type & PERF_SAMPLE_REGS_USER) {
		if (sample->user_regs.abi) {
			result += sizeof(u64);
			sz = hweight_long(sample_regs_user) * sizeof(u64);
			result += sz;
		} else {
			result += sizeof(u64);
		}
	}

	if (type & PERF_SAMPLE_STACK_USER) {
		sz = sample->user_stack.size;
		result += sizeof(u64);
		if (sz) {
			result += sz;
			result += sizeof(u64);
		}
	}

	if (type & PERF_SAMPLE_WEIGHT)
		result += sizeof(u64);

	if (type & PERF_SAMPLE_DATA_SRC)
		result += sizeof(u64);

1581 1582 1583
	if (type & PERF_SAMPLE_TRANSACTION)
		result += sizeof(u64);

1584 1585 1586
	return result;
}

1587
int perf_event__synthesize_sample(union perf_event *event, u64 type,
1588
				  u64 sample_regs_user, u64 read_format,
1589 1590 1591 1592
				  const struct perf_sample *sample,
				  bool swapped)
{
	u64 *array;
1593
	size_t sz;
1594 1595 1596 1597
	/*
	 * used for cross-endian analysis. See git commit 65014ab3
	 * for why this goofiness is needed.
	 */
1598
	union u64_swap u;
1599 1600 1601

	array = event->sample.array;

1602 1603 1604 1605 1606
	if (type & PERF_SAMPLE_IDENTIFIER) {
		*array = sample->id;
		array++;
	}

1607
	if (type & PERF_SAMPLE_IP) {
1608
		*array = sample->ip;
1609 1610 1611 1612 1613 1614 1615 1616
		array++;
	}

	if (type & PERF_SAMPLE_TID) {
		u.val32[0] = sample->pid;
		u.val32[1] = sample->tid;
		if (swapped) {
			/*
1617
			 * Inverse of what is done in perf_evsel__parse_sample
1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651
			 */
			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) {
			/*
1652
			 * Inverse of what is done in perf_evsel__parse_sample
1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665
			 */
			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++;
	}

1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756
	if (type & PERF_SAMPLE_READ) {
		if (read_format & PERF_FORMAT_GROUP)
			*array = sample->read.group.nr;
		else
			*array = sample->read.one.value;
		array++;

		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
			*array = sample->read.time_enabled;
			array++;
		}

		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
			*array = sample->read.time_running;
			array++;
		}

		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
		if (read_format & PERF_FORMAT_GROUP) {
			sz = sample->read.group.nr *
			     sizeof(struct sample_read_value);
			memcpy(array, sample->read.group.values, sz);
			array = (void *)array + sz;
		} else {
			*array = sample->read.one.id;
			array++;
		}
	}

	if (type & PERF_SAMPLE_CALLCHAIN) {
		sz = (sample->callchain->nr + 1) * sizeof(u64);
		memcpy(array, sample->callchain, sz);
		array = (void *)array + sz;
	}

	if (type & PERF_SAMPLE_RAW) {
		u.val32[0] = sample->raw_size;
		if (WARN_ONCE(swapped,
			      "Endianness of raw data not corrected!\n")) {
			/*
			 * Inverse of what is done in perf_evsel__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 = (void *)array + sizeof(u32);

		memcpy(array, sample->raw_data, sample->raw_size);
		array = (void *)array + sample->raw_size;
	}

	if (type & PERF_SAMPLE_BRANCH_STACK) {
		sz = sample->branch_stack->nr * sizeof(struct branch_entry);
		sz += sizeof(u64);
		memcpy(array, sample->branch_stack, sz);
		array = (void *)array + sz;
	}

	if (type & PERF_SAMPLE_REGS_USER) {
		if (sample->user_regs.abi) {
			*array++ = sample->user_regs.abi;
			sz = hweight_long(sample_regs_user) * sizeof(u64);
			memcpy(array, sample->user_regs.regs, sz);
			array = (void *)array + sz;
		} else {
			*array++ = 0;
		}
	}

	if (type & PERF_SAMPLE_STACK_USER) {
		sz = sample->user_stack.size;
		*array++ = sz;
		if (sz) {
			memcpy(array, sample->user_stack.data, sz);
			array = (void *)array + sz;
			*array++ = sz;
		}
	}

	if (type & PERF_SAMPLE_WEIGHT) {
		*array = sample->weight;
		array++;
	}

	if (type & PERF_SAMPLE_DATA_SRC) {
		*array = sample->data_src;
		array++;
	}

1757 1758 1759 1760 1761
	if (type & PERF_SAMPLE_TRANSACTION) {
		*array = sample->transaction;
		array++;
	}

1762 1763
	return 0;
}
1764

1765 1766 1767 1768 1769
struct format_field *perf_evsel__field(struct perf_evsel *evsel, const char *name)
{
	return pevent_find_field(evsel->tp_format, name);
}

1770
void *perf_evsel__rawptr(struct perf_evsel *evsel, struct perf_sample *sample,
1771 1772
			 const char *name)
{
1773
	struct format_field *field = perf_evsel__field(evsel, name);
1774 1775
	int offset;

1776 1777
	if (!field)
		return NULL;
1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791

	offset = field->offset;

	if (field->flags & FIELD_IS_DYNAMIC) {
		offset = *(int *)(sample->raw_data + field->offset);
		offset &= 0xffff;
	}

	return sample->raw_data + offset;
}

u64 perf_evsel__intval(struct perf_evsel *evsel, struct perf_sample *sample,
		       const char *name)
{
1792
	struct format_field *field = perf_evsel__field(evsel, name);
1793 1794
	void *ptr;
	u64 value;
1795

1796 1797
	if (!field)
		return 0;
1798

1799
	ptr = sample->raw_data + field->offset;
1800

1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831
	switch (field->size) {
	case 1:
		return *(u8 *)ptr;
	case 2:
		value = *(u16 *)ptr;
		break;
	case 4:
		value = *(u32 *)ptr;
		break;
	case 8:
		value = *(u64 *)ptr;
		break;
	default:
		return 0;
	}

	if (!evsel->needs_swap)
		return value;

	switch (field->size) {
	case 2:
		return bswap_16(value);
	case 4:
		return bswap_32(value);
	case 8:
		return bswap_64(value);
	default:
		return 0;
	}

	return 0;
1832
}
1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861

static int comma_fprintf(FILE *fp, bool *first, const char *fmt, ...)
{
	va_list args;
	int ret = 0;

	if (!*first) {
		ret += fprintf(fp, ",");
	} else {
		ret += fprintf(fp, ":");
		*first = false;
	}

	va_start(args, fmt);
	ret += vfprintf(fp, fmt, args);
	va_end(args);
	return ret;
}

static int __if_fprintf(FILE *fp, bool *first, const char *field, u64 value)
{
	if (value == 0)
		return 0;

	return comma_fprintf(fp, first, " %s: %" PRIu64, field, value);
}

#define if_print(field) printed += __if_fprintf(fp, &first, #field, evsel->attr.field)

1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890
struct bit_names {
	int bit;
	const char *name;
};

static int bits__fprintf(FILE *fp, const char *field, u64 value,
			 struct bit_names *bits, bool *first)
{
	int i = 0, printed = comma_fprintf(fp, first, " %s: ", field);
	bool first_bit = true;

	do {
		if (value & bits[i].bit) {
			printed += fprintf(fp, "%s%s", first_bit ? "" : "|", bits[i].name);
			first_bit = false;
		}
	} while (bits[++i].name != NULL);

	return printed;
}

static int sample_type__fprintf(FILE *fp, bool *first, u64 value)
{
#define bit_name(n) { PERF_SAMPLE_##n, #n }
	struct bit_names bits[] = {
		bit_name(IP), bit_name(TID), bit_name(TIME), bit_name(ADDR),
		bit_name(READ), bit_name(CALLCHAIN), bit_name(ID), bit_name(CPU),
		bit_name(PERIOD), bit_name(STREAM_ID), bit_name(RAW),
		bit_name(BRANCH_STACK), bit_name(REGS_USER), bit_name(STACK_USER),
1891
		bit_name(IDENTIFIER),
1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909
		{ .name = NULL, }
	};
#undef bit_name
	return bits__fprintf(fp, "sample_type", value, bits, first);
}

static int read_format__fprintf(FILE *fp, bool *first, u64 value)
{
#define bit_name(n) { PERF_FORMAT_##n, #n }
	struct bit_names bits[] = {
		bit_name(TOTAL_TIME_ENABLED), bit_name(TOTAL_TIME_RUNNING),
		bit_name(ID), bit_name(GROUP),
		{ .name = NULL, }
	};
#undef bit_name
	return bits__fprintf(fp, "read_format", value, bits, first);
}

1910 1911 1912 1913
int perf_evsel__fprintf(struct perf_evsel *evsel,
			struct perf_attr_details *details, FILE *fp)
{
	bool first = true;
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	int printed = 0;

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	if (details->event_group) {
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		struct perf_evsel *pos;

		if (!perf_evsel__is_group_leader(evsel))
			return 0;

		if (evsel->nr_members > 1)
			printed += fprintf(fp, "%s{", evsel->group_name ?: "");

		printed += fprintf(fp, "%s", perf_evsel__name(evsel));
		for_each_group_member(pos, evsel)
			printed += fprintf(fp, ",%s", perf_evsel__name(pos));

		if (evsel->nr_members > 1)
			printed += fprintf(fp, "}");
		goto out;
	}

	printed += fprintf(fp, "%s", perf_evsel__name(evsel));
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	if (details->verbose || details->freq) {
		printed += comma_fprintf(fp, &first, " sample_freq=%" PRIu64,
					 (u64)evsel->attr.sample_freq);
	}

	if (details->verbose) {
		if_print(type);
		if_print(config);
		if_print(config1);
		if_print(config2);
		if_print(size);
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		printed += sample_type__fprintf(fp, &first, evsel->attr.sample_type);
		if (evsel->attr.read_format)
			printed += read_format__fprintf(fp, &first, evsel->attr.read_format);
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		if_print(disabled);
		if_print(inherit);
		if_print(pinned);
		if_print(exclusive);
		if_print(exclude_user);
		if_print(exclude_kernel);
		if_print(exclude_hv);
		if_print(exclude_idle);
		if_print(mmap);
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		if_print(mmap2);
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		if_print(comm);
		if_print(freq);
		if_print(inherit_stat);
		if_print(enable_on_exec);
		if_print(task);
		if_print(watermark);
		if_print(precise_ip);
		if_print(mmap_data);
		if_print(sample_id_all);
		if_print(exclude_host);
		if_print(exclude_guest);
		if_print(__reserved_1);
		if_print(wakeup_events);
		if_print(bp_type);
		if_print(branch_sample_type);
	}
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out:
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	fputc('\n', fp);
	return ++printed;
}
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bool perf_evsel__fallback(struct perf_evsel *evsel, int err,
			  char *msg, size_t msgsize)
{
1984
	if ((err == ENOENT || err == ENXIO || err == ENODEV) &&
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	    evsel->attr.type   == PERF_TYPE_HARDWARE &&
	    evsel->attr.config == PERF_COUNT_HW_CPU_CYCLES) {
		/*
		 * If it's cycles then fall back to hrtimer based
		 * cpu-clock-tick sw counter, which is always available even if
		 * no PMU support.
		 *
		 * PPC returns ENXIO until 2.6.37 (behavior changed with commit
		 * b0a873e).
		 */
		scnprintf(msg, msgsize, "%s",
"The cycles event is not supported, trying to fall back to cpu-clock-ticks");

		evsel->attr.type   = PERF_TYPE_SOFTWARE;
		evsel->attr.config = PERF_COUNT_SW_CPU_CLOCK;

		free(evsel->name);
		evsel->name = NULL;
		return true;
	}

	return false;
}
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int perf_evsel__open_strerror(struct perf_evsel *evsel,
			      struct perf_target *target,
			      int err, char *msg, size_t size)
{
	switch (err) {
	case EPERM:
	case EACCES:
2016
		return scnprintf(msg, size,
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		 "You may not have permission to collect %sstats.\n"
		 "Consider tweaking /proc/sys/kernel/perf_event_paranoid:\n"
		 " -1 - Not paranoid at all\n"
		 "  0 - Disallow raw tracepoint access for unpriv\n"
		 "  1 - Disallow cpu events for unpriv\n"
		 "  2 - Disallow kernel profiling for unpriv",
				 target->system_wide ? "system-wide " : "");
	case ENOENT:
		return scnprintf(msg, size, "The %s event is not supported.",
				 perf_evsel__name(evsel));
	case EMFILE:
		return scnprintf(msg, size, "%s",
			 "Too many events are opened.\n"
			 "Try again after reducing the number of events.");
	case ENODEV:
		if (target->cpu_list)
			return scnprintf(msg, size, "%s",
	 "No such device - did you specify an out-of-range profile CPU?\n");
		break;
	case EOPNOTSUPP:
		if (evsel->attr.precise_ip)
			return scnprintf(msg, size, "%s",
	"\'precise\' request may not be supported. Try removing 'p' modifier.");
#if defined(__i386__) || defined(__x86_64__)
		if (evsel->attr.type == PERF_TYPE_HARDWARE)
			return scnprintf(msg, size, "%s",
	"No hardware sampling interrupt available.\n"
	"No APIC? If so then you can boot the kernel with the \"lapic\" boot parameter to force-enable it.");
#endif
		break;
	default:
		break;
	}

	return scnprintf(msg, size,
	"The sys_perf_event_open() syscall returned with %d (%s) for event (%s).  \n"
	"/bin/dmesg may provide additional information.\n"
	"No CONFIG_PERF_EVENTS=y kernel support configured?\n",
			 err, strerror(err), perf_evsel__name(evsel));
}