evsel.c 47.9 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
	}

665 666 667
	if (opts->sample_address)
		attr->sample_type	|= PERF_SAMPLE_DATA_SRC;

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

677 678 679
	if (opts->sample_weight)
		attr->sample_type	|= PERF_SAMPLE_WEIGHT;

680 681 682
	attr->mmap  = track;
	attr->mmap2 = track && !perf_missing_features.mmap2;
	attr->comm  = track;
683

684 685 686
	if (opts->sample_transaction)
		attr->sample_type	|= PERF_SAMPLE_TRANSACTION;

687 688 689 690 691 692
	/*
	 * XXX see the function comment above
	 *
	 * Disabling only independent events or group leaders,
	 * keeping group members enabled.
	 */
693
	if (perf_evsel__is_group_leader(evsel))
694 695 696 697 698 699
		attr->disabled = 1;

	/*
	 * Setting enable_on_exec for independent events and
	 * group leaders for traced executed by perf.
	 */
700
	if (perf_target__none(&opts->target) && perf_evsel__is_group_leader(evsel))
701 702 703
		attr->enable_on_exec = 1;
}

704 705
int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
{
706
	int cpu, thread;
707
	evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
708 709 710 711 712 713 714 715 716

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

717 718 719
	return evsel->fd != NULL ? 0 : -ENOMEM;
}

720 721
static int perf_evsel__run_ioctl(struct perf_evsel *evsel, int ncpus, int nthreads,
			  int ioc,  void *arg)
722 723 724 725 726 727
{
	int cpu, thread;

	for (cpu = 0; cpu < ncpus; cpu++) {
		for (thread = 0; thread < nthreads; thread++) {
			int fd = FD(evsel, cpu, thread),
728
			    err = ioctl(fd, ioc, arg);
729 730 731 732 733 734 735 736 737

			if (err)
				return err;
		}
	}

	return 0;
}

738 739 740 741 742 743 744 745 746 747 748 749 750 751 752
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);
}

753 754
int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
{
755 756 757 758 759 760 761 762 763 764 765 766
	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;
767 768
}

769 770 771 772 773 774
void perf_evsel__reset_counts(struct perf_evsel *evsel, int ncpus)
{
	memset(evsel->counts, 0, (sizeof(*evsel->counts) +
				 (ncpus * sizeof(struct perf_counts_values))));
}

775 776 777 778 779 780 781
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;
}

782 783 784 785 786 787
void perf_evsel__free_fd(struct perf_evsel *evsel)
{
	xyarray__delete(evsel->fd);
	evsel->fd = NULL;
}

788 789
void perf_evsel__free_id(struct perf_evsel *evsel)
{
790 791 792
	xyarray__delete(evsel->sample_id);
	evsel->sample_id = NULL;
	free(evsel->id);
793 794 795
	evsel->id = NULL;
}

796 797 798 799 800 801 802 803 804 805 806
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;
		}
}

807 808 809 810 811
void perf_evsel__free_counts(struct perf_evsel *evsel)
{
	free(evsel->counts);
}

812
void perf_evsel__exit(struct perf_evsel *evsel)
813 814
{
	assert(list_empty(&evsel->node));
815 816
	perf_evsel__free_fd(evsel);
	perf_evsel__free_id(evsel);
817 818 819 820 821
}

void perf_evsel__delete(struct perf_evsel *evsel)
{
	perf_evsel__exit(evsel);
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822
	close_cgroup(evsel->cgrp);
823
	free(evsel->group_name);
824
	if (evsel->tp_format)
825
		pevent_free_format(evsel->tp_format);
826
	free(evsel->name);
827 828
	free(evsel);
}
829

830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851
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;
}

852 853 854 855 856 857 858 859 860
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;

861 862 863
	if (evsel->counts == NULL && perf_evsel__alloc_counts(evsel, cpu + 1) < 0)
		return -ENOMEM;

864 865 866
	if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) < 0)
		return -errno;

867 868
	compute_deltas(evsel, cpu, &count);

869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887
	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;

888
	aggr->val = aggr->ena = aggr->run = 0;
889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906

	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;
			}
		}
	}

907 908
	compute_deltas(evsel, -1, aggr);

909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925
	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;
}
926

927 928 929 930 931
static int get_group_fd(struct perf_evsel *evsel, int cpu, int thread)
{
	struct perf_evsel *leader = evsel->leader;
	int fd;

932
	if (perf_evsel__is_group_leader(evsel))
933 934 935 936 937 938 939 940 941 942 943 944 945 946
		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
947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988
#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);
989
	ret += PRINT_ATTR_U32(mmap2);
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990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006

	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;
}

1007
static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1008
			      struct thread_map *threads)
1009
{
1010
	int cpu, thread;
S
Stephane Eranian 已提交
1011
	unsigned long flags = 0;
1012
	int pid = -1, err;
1013
	enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;
1014

1015 1016
	if (evsel->fd == NULL &&
	    perf_evsel__alloc_fd(evsel, cpus->nr, threads->nr) < 0)
1017
		return -ENOMEM;
1018

S
Stephane Eranian 已提交
1019 1020 1021 1022 1023
	if (evsel->cgrp) {
		flags = PERF_FLAG_PID_CGROUP;
		pid = evsel->cgrp->fd;
	}

1024
fallback_missing_features:
1025 1026
	if (perf_missing_features.mmap2)
		evsel->attr.mmap2 = 0;
1027 1028 1029 1030 1031 1032
	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
1033 1034 1035
	if (verbose >= 2)
		perf_event_attr__fprintf(&evsel->attr, stderr);

1036
	for (cpu = 0; cpu < cpus->nr; cpu++) {
1037

1038
		for (thread = 0; thread < threads->nr; thread++) {
1039
			int group_fd;
S
Stephane Eranian 已提交
1040 1041 1042 1043

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

1044
			group_fd = get_group_fd(evsel, cpu, thread);
1045
retry_open:
A
Adrian Hunter 已提交
1046 1047 1048
			pr_debug2("perf_event_open: pid %d  cpu %d  group_fd %d  flags %#lx\n",
				  pid, cpus->map[cpu], group_fd, flags);

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

	return 0;

1063
try_fallback:
1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087
	/*
	 * 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;
	}

1088 1089 1090
	if (err != -EINVAL || cpu > 0 || thread > 0)
		goto out_close;

1091 1092 1093 1094 1095
	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)) {
1096 1097 1098 1099 1100 1101 1102
		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;
	}

1103
out_close:
1104 1105 1106 1107 1108 1109 1110
	do {
		while (--thread >= 0) {
			close(FD(evsel, cpu, thread));
			FD(evsel, cpu, thread) = -1;
		}
		thread = threads->nr;
	} while (--cpu >= 0);
1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121
	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;
1122 1123
}

1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139
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, },
};

1140
int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1141
		     struct thread_map *threads)
1142
{
1143 1144 1145
	if (cpus == NULL) {
		/* Work around old compiler warnings about strict aliasing */
		cpus = &empty_cpu_map.map;
1146 1147
	}

1148 1149
	if (threads == NULL)
		threads = &empty_thread_map.map;
1150

1151
	return __perf_evsel__open(evsel, cpus, threads);
1152 1153
}

1154
int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
1155
			     struct cpu_map *cpus)
1156
{
1157
	return __perf_evsel__open(evsel, cpus, &empty_thread_map.map);
1158
}
1159

1160
int perf_evsel__open_per_thread(struct perf_evsel *evsel,
1161
				struct thread_map *threads)
1162
{
1163
	return __perf_evsel__open(evsel, &empty_cpu_map.map, threads);
1164
}
1165

1166 1167 1168
static int perf_evsel__parse_id_sample(const struct perf_evsel *evsel,
				       const union perf_event *event,
				       struct perf_sample *sample)
1169
{
1170
	u64 type = evsel->attr.sample_type;
1171
	const u64 *array = event->sample.array;
1172
	bool swapped = evsel->needs_swap;
1173
	union u64_swap u;
1174 1175 1176 1177

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

1178 1179 1180 1181 1182
	if (type & PERF_SAMPLE_IDENTIFIER) {
		sample->id = *array;
		array--;
	}

1183
	if (type & PERF_SAMPLE_CPU) {
1184 1185 1186 1187 1188 1189 1190 1191
		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];
1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210
		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) {
1211 1212 1213 1214 1215 1216 1217 1218 1219 1220
		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];
1221 1222 1223 1224 1225
	}

	return 0;
}

1226 1227
static inline bool overflow(const void *endp, u16 max_size, const void *offset,
			    u64 size)
1228
{
1229 1230
	return size > max_size || offset + size > endp;
}
1231

1232 1233 1234 1235 1236
#define OVERFLOW_CHECK(offset, size, max_size)				\
	do {								\
		if (overflow(endp, (max_size), (offset), (size)))	\
			return -EFAULT;					\
	} while (0)
1237

1238 1239
#define OVERFLOW_CHECK_u64(offset) \
	OVERFLOW_CHECK(offset, sizeof(u64), sizeof(u64))
1240

1241
int perf_evsel__parse_sample(struct perf_evsel *evsel, union perf_event *event,
1242
			     struct perf_sample *data)
1243
{
1244
	u64 type = evsel->attr.sample_type;
1245
	bool swapped = evsel->needs_swap;
1246
	const u64 *array;
1247 1248 1249
	u16 max_size = event->header.size;
	const void *endp = (void *)event + max_size;
	u64 sz;
1250

1251 1252 1253 1254
	/*
	 * used for cross-endian analysis. See git commit 65014ab3
	 * for why this goofiness is needed.
	 */
1255
	union u64_swap u;
1256

1257
	memset(data, 0, sizeof(*data));
1258 1259
	data->cpu = data->pid = data->tid = -1;
	data->stream_id = data->id = data->time = -1ULL;
1260
	data->period = 1;
1261
	data->weight = 0;
1262 1263

	if (event->header.type != PERF_RECORD_SAMPLE) {
1264
		if (!evsel->attr.sample_id_all)
1265
			return 0;
1266
		return perf_evsel__parse_id_sample(evsel, event, data);
1267 1268 1269 1270
	}

	array = event->sample.array;

1271 1272 1273 1274 1275
	/*
	 * 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.
	 */
1276
	if (evsel->sample_size + sizeof(event->header) > event->header.size)
1277 1278
		return -EFAULT;

1279 1280 1281 1282 1283 1284
	data->id = -1ULL;
	if (type & PERF_SAMPLE_IDENTIFIER) {
		data->id = *array;
		array++;
	}

1285
	if (type & PERF_SAMPLE_IP) {
1286
		data->ip = *array;
1287 1288 1289 1290
		array++;
	}

	if (type & PERF_SAMPLE_TID) {
1291 1292 1293 1294 1295 1296 1297 1298 1299 1300
		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];
1301 1302 1303 1304 1305 1306 1307 1308
		array++;
	}

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

1309
	data->addr = 0;
1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325
	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) {
1326 1327 1328 1329 1330 1331 1332 1333 1334

		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];
1335 1336 1337 1338 1339 1340 1341 1342 1343
		array++;
	}

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

	if (type & PERF_SAMPLE_READ) {
1344 1345
		u64 read_format = evsel->attr.read_format;

1346
		OVERFLOW_CHECK_u64(array);
1347 1348 1349 1350 1351 1352 1353 1354
		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) {
1355
			OVERFLOW_CHECK_u64(array);
1356 1357 1358 1359 1360
			data->read.time_enabled = *array;
			array++;
		}

		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1361
			OVERFLOW_CHECK_u64(array);
1362 1363 1364 1365 1366 1367
			data->read.time_running = *array;
			array++;
		}

		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
		if (read_format & PERF_FORMAT_GROUP) {
1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378
			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;
1379
		} else {
1380
			OVERFLOW_CHECK_u64(array);
1381 1382 1383
			data->read.one.id = *array;
			array++;
		}
1384 1385 1386
	}

	if (type & PERF_SAMPLE_CALLCHAIN) {
1387
		const u64 max_callchain_nr = UINT64_MAX / sizeof(u64);
1388

1389 1390 1391
		OVERFLOW_CHECK_u64(array);
		data->callchain = (struct ip_callchain *)array++;
		if (data->callchain->nr > max_callchain_nr)
1392
			return -EFAULT;
1393 1394 1395
		sz = data->callchain->nr * sizeof(u64);
		OVERFLOW_CHECK(array, sz, max_size);
		array = (void *)array + sz;
1396 1397 1398
	}

	if (type & PERF_SAMPLE_RAW) {
1399
		OVERFLOW_CHECK_u64(array);
1400 1401 1402 1403 1404 1405 1406 1407 1408
		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];
1409
		array = (void *)array + sizeof(u32);
1410

1411 1412 1413
		OVERFLOW_CHECK(array, data->raw_size, max_size);
		data->raw_data = (void *)array;
		array = (void *)array + data->raw_size;
1414 1415
	}

1416
	if (type & PERF_SAMPLE_BRANCH_STACK) {
1417 1418
		const u64 max_branch_nr = UINT64_MAX /
					  sizeof(struct branch_entry);
1419

1420 1421
		OVERFLOW_CHECK_u64(array);
		data->branch_stack = (struct branch_stack *)array++;
1422

1423 1424
		if (data->branch_stack->nr > max_branch_nr)
			return -EFAULT;
1425
		sz = data->branch_stack->nr * sizeof(struct branch_entry);
1426 1427
		OVERFLOW_CHECK(array, sz, max_size);
		array = (void *)array + sz;
1428
	}
1429 1430

	if (type & PERF_SAMPLE_REGS_USER) {
1431
		OVERFLOW_CHECK_u64(array);
1432 1433
		data->user_regs.abi = *array;
		array++;
1434

1435
		if (data->user_regs.abi) {
1436 1437 1438 1439
			u64 regs_user = evsel->attr.sample_regs_user;

			sz = hweight_long(regs_user) * sizeof(u64);
			OVERFLOW_CHECK(array, sz, max_size);
1440
			data->user_regs.regs = (u64 *)array;
1441
			array = (void *)array + sz;
1442 1443 1444 1445
		}
	}

	if (type & PERF_SAMPLE_STACK_USER) {
1446 1447
		OVERFLOW_CHECK_u64(array);
		sz = *array++;
1448 1449 1450 1451

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

1452
		if (!sz) {
1453 1454
			data->user_stack.size = 0;
		} else {
1455
			OVERFLOW_CHECK(array, sz, max_size);
1456
			data->user_stack.data = (char *)array;
1457 1458
			array = (void *)array + sz;
			OVERFLOW_CHECK_u64(array);
1459
			data->user_stack.size = *array++;
1460 1461 1462
			if (WARN_ONCE(data->user_stack.size > sz,
				      "user stack dump failure\n"))
				return -EFAULT;
1463 1464 1465
		}
	}

1466 1467
	data->weight = 0;
	if (type & PERF_SAMPLE_WEIGHT) {
1468
		OVERFLOW_CHECK_u64(array);
1469 1470 1471 1472
		data->weight = *array;
		array++;
	}

1473 1474
	data->data_src = PERF_MEM_DATA_SRC_NONE;
	if (type & PERF_SAMPLE_DATA_SRC) {
1475
		OVERFLOW_CHECK_u64(array);
1476 1477 1478 1479
		data->data_src = *array;
		array++;
	}

1480 1481 1482 1483 1484 1485
	data->transaction = 0;
	if (type & PERF_SAMPLE_TRANSACTION) {
		data->transaction = *array;
		array++;
	}

1486 1487
	return 0;
}
1488

1489 1490 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);

	return result;
}

1581
int perf_event__synthesize_sample(union perf_event *event, u64 type,
1582
				  u64 sample_regs_user, u64 read_format,
1583 1584 1585 1586
				  const struct perf_sample *sample,
				  bool swapped)
{
	u64 *array;
1587
	size_t sz;
1588 1589 1590 1591
	/*
	 * used for cross-endian analysis. See git commit 65014ab3
	 * for why this goofiness is needed.
	 */
1592
	union u64_swap u;
1593 1594 1595

	array = event->sample.array;

1596 1597 1598 1599 1600
	if (type & PERF_SAMPLE_IDENTIFIER) {
		*array = sample->id;
		array++;
	}

1601
	if (type & PERF_SAMPLE_IP) {
1602
		*array = sample->ip;
1603 1604 1605 1606 1607 1608 1609 1610
		array++;
	}

	if (type & PERF_SAMPLE_TID) {
		u.val32[0] = sample->pid;
		u.val32[1] = sample->tid;
		if (swapped) {
			/*
1611
			 * Inverse of what is done in perf_evsel__parse_sample
1612 1613 1614 1615 1616 1617 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
			 */
			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) {
			/*
1646
			 * Inverse of what is done in perf_evsel__parse_sample
1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659
			 */
			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++;
	}

1660 1661 1662 1663 1664 1665 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
	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++;
	}

1751 1752
	return 0;
}
1753

1754 1755 1756 1757 1758
struct format_field *perf_evsel__field(struct perf_evsel *evsel, const char *name)
{
	return pevent_find_field(evsel->tp_format, name);
}

1759
void *perf_evsel__rawptr(struct perf_evsel *evsel, struct perf_sample *sample,
1760 1761
			 const char *name)
{
1762
	struct format_field *field = perf_evsel__field(evsel, name);
1763 1764
	int offset;

1765 1766
	if (!field)
		return NULL;
1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780

	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)
{
1781
	struct format_field *field = perf_evsel__field(evsel, name);
1782 1783
	void *ptr;
	u64 value;
1784

1785 1786
	if (!field)
		return 0;
1787

1788
	ptr = sample->raw_data + field->offset;
1789

1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820
	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;
1821
}
1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850

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)

1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879
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),
1880
		bit_name(IDENTIFIER),
1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898
		{ .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);
}

1899 1900 1901 1902
int perf_evsel__fprintf(struct perf_evsel *evsel,
			struct perf_attr_details *details, FILE *fp)
{
	bool first = true;
N
Namhyung Kim 已提交
1903 1904
	int printed = 0;

1905
	if (details->event_group) {
N
Namhyung Kim 已提交
1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923
		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));
1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935

	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);
1936 1937 1938
		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);
1939 1940 1941 1942 1943 1944 1945 1946 1947
		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);
1948
		if_print(mmap2);
1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964
		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);
	}
N
Namhyung Kim 已提交
1965
out:
1966 1967 1968
	fputc('\n', fp);
	return ++printed;
}
1969 1970 1971 1972

bool perf_evsel__fallback(struct perf_evsel *evsel, int err,
			  char *msg, size_t msgsize)
{
1973
	if ((err == ENOENT || err == ENXIO || err == ENODEV) &&
1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996
	    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;
}
1997 1998 1999 2000 2001 2002 2003 2004

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:
2005
		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));
}