evsel.c 48.2 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 <api/fs/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"
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Adrian Hunter 已提交
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#include "debug.h"
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#include "trace-event.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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	evsel->unit	   = "";
	evsel->scale	   = 1.0;
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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_idx(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 perf_evsel *perf_evsel__newtp_idx(const char *sys, const char *name, int idx)
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{
	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 = trace_event__tp_format(sys, name);
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		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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	zfree(&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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static void
perf_evsel__config_callgraph(struct perf_evsel *evsel,
			     struct record_opts *opts)
{
	bool function = perf_evsel__is_function_event(evsel);
	struct perf_event_attr *attr = &evsel->attr;

	perf_evsel__set_sample_bit(evsel, CALLCHAIN);

	if (opts->call_graph == CALLCHAIN_DWARF) {
		if (!function) {
			perf_evsel__set_sample_bit(evsel, REGS_USER);
			perf_evsel__set_sample_bit(evsel, STACK_USER);
			attr->sample_regs_user = PERF_REGS_MASK;
			attr->sample_stack_user = opts->stack_dump_size;
			attr->exclude_callchain_user = 1;
		} else {
			pr_info("Cannot use DWARF unwind for function trace event,"
				" falling back to framepointers.\n");
		}
	}

	if (function) {
		pr_info("Disabling user space callchains for function trace event.\n");
		attr->exclude_callchain_user = 1;
	}
}

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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 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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	bool per_cpu = opts->target.default_per_cpu && !opts->target.per_thread;
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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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	/*
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	 * We default some events to have a default interval. But keep
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	 * it a weak assumption overridable by the user.
	 */
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	if (!attr->sample_period || (opts->user_freq != UINT_MAX ||
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				     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_enabled && !evsel->no_aux_samples)
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		perf_evsel__config_callgraph(evsel, opts);
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	if (target__has_cpu(&opts->target))
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		perf_evsel__set_sample_bit(evsel, CPU);
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	if (opts->period)
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		perf_evsel__set_sample_bit(evsel, PERIOD);
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	if (!perf_missing_features.sample_id_all &&
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	    (opts->sample_time || !opts->no_inherit ||
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	     target__has_cpu(&opts->target) || per_cpu))
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		perf_evsel__set_sample_bit(evsel, TIME);
639

640
	if (opts->raw_samples && !evsel->no_aux_samples) {
641 642 643
		perf_evsel__set_sample_bit(evsel, TIME);
		perf_evsel__set_sample_bit(evsel, RAW);
		perf_evsel__set_sample_bit(evsel, CPU);
644 645
	}

646
	if (opts->sample_address)
647
		perf_evsel__set_sample_bit(evsel, DATA_SRC);
648

649
	if (opts->no_buffering) {
650 651 652
		attr->watermark = 0;
		attr->wakeup_events = 1;
	}
653
	if (opts->branch_stack && !evsel->no_aux_samples) {
654
		perf_evsel__set_sample_bit(evsel, BRANCH_STACK);
655 656
		attr->branch_sample_type = opts->branch_stack;
	}
657

658
	if (opts->sample_weight)
659
		perf_evsel__set_sample_bit(evsel, WEIGHT);
660

661
	attr->mmap  = track;
662
	attr->mmap2 = track && !perf_missing_features.mmap2;
663
	attr->comm  = track;
664

665
	if (opts->sample_transaction)
666
		perf_evsel__set_sample_bit(evsel, TRANSACTION);
667

668 669 670 671 672 673
	/*
	 * XXX see the function comment above
	 *
	 * Disabling only independent events or group leaders,
	 * keeping group members enabled.
	 */
674
	if (perf_evsel__is_group_leader(evsel))
675 676 677 678 679 680
		attr->disabled = 1;

	/*
	 * Setting enable_on_exec for independent events and
	 * group leaders for traced executed by perf.
	 */
681 682
	if (target__none(&opts->target) && perf_evsel__is_group_leader(evsel) &&
		!opts->initial_delay)
683
		attr->enable_on_exec = 1;
684 685 686 687 688

	if (evsel->immediate) {
		attr->disabled = 0;
		attr->enable_on_exec = 0;
	}
689 690
}

691 692
int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
{
693
	int cpu, thread;
694
	evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
695 696 697 698 699 700 701 702 703

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

704 705 706
	return evsel->fd != NULL ? 0 : -ENOMEM;
}

707 708
static int perf_evsel__run_ioctl(struct perf_evsel *evsel, int ncpus, int nthreads,
			  int ioc,  void *arg)
709 710 711 712 713 714
{
	int cpu, thread;

	for (cpu = 0; cpu < ncpus; cpu++) {
		for (thread = 0; thread < nthreads; thread++) {
			int fd = FD(evsel, cpu, thread),
715
			    err = ioctl(fd, ioc, arg);
716 717 718 719 720 721 722 723 724

			if (err)
				return err;
		}
	}

	return 0;
}

725 726 727 728 729 730 731 732 733 734 735 736 737 738 739
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);
}

740 741
int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
{
742 743 744 745 746 747 748 749 750 751 752 753
	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;
754 755
}

756 757 758 759 760 761
void perf_evsel__reset_counts(struct perf_evsel *evsel, int ncpus)
{
	memset(evsel->counts, 0, (sizeof(*evsel->counts) +
				 (ncpus * sizeof(struct perf_counts_values))));
}

762 763 764 765 766 767 768
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;
}

769 770 771 772 773 774
void perf_evsel__free_fd(struct perf_evsel *evsel)
{
	xyarray__delete(evsel->fd);
	evsel->fd = NULL;
}

775 776
void perf_evsel__free_id(struct perf_evsel *evsel)
{
777 778
	xyarray__delete(evsel->sample_id);
	evsel->sample_id = NULL;
779
	zfree(&evsel->id);
780 781
}

782 783 784 785 786 787 788 789 790 791 792
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;
		}
}

793 794
void perf_evsel__free_counts(struct perf_evsel *evsel)
{
795
	zfree(&evsel->counts);
796 797
}

798
void perf_evsel__exit(struct perf_evsel *evsel)
799 800
{
	assert(list_empty(&evsel->node));
801 802
	perf_evsel__free_fd(evsel);
	perf_evsel__free_id(evsel);
803 804 805 806 807
}

void perf_evsel__delete(struct perf_evsel *evsel)
{
	perf_evsel__exit(evsel);
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808
	close_cgroup(evsel->cgrp);
809
	zfree(&evsel->group_name);
810
	if (evsel->tp_format)
811
		pevent_free_format(evsel->tp_format);
812
	zfree(&evsel->name);
813 814
	free(evsel);
}
815

816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837
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;
}

838 839 840 841 842 843 844 845 846
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;

847 848 849
	if (evsel->counts == NULL && perf_evsel__alloc_counts(evsel, cpu + 1) < 0)
		return -ENOMEM;

850 851 852
	if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) < 0)
		return -errno;

853 854
	compute_deltas(evsel, cpu, &count);

855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873
	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;

874
	aggr->val = aggr->ena = aggr->run = 0;
875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892

	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;
			}
		}
	}

893 894
	compute_deltas(evsel, -1, aggr);

895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911
	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;
}
912

913 914 915 916 917
static int get_group_fd(struct perf_evsel *evsel, int cpu, int thread)
{
	struct perf_evsel *leader = evsel->leader;
	int fd;

918
	if (perf_evsel__is_group_leader(evsel))
919 920 921 922 923 924 925 926 927 928 929 930 931 932
		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
933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967
#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);
968
	ret += PRINT_ATTR2(mmap2, comm_exec);
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969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992
	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);

	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;
}

993
static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
994
			      struct thread_map *threads)
995
{
996
	int cpu, thread;
S
Stephane Eranian 已提交
997
	unsigned long flags = 0;
998
	int pid = -1, err;
999
	enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;
1000

1001 1002
	if (evsel->fd == NULL &&
	    perf_evsel__alloc_fd(evsel, cpus->nr, threads->nr) < 0)
1003
		return -ENOMEM;
1004

S
Stephane Eranian 已提交
1005 1006 1007 1008 1009
	if (evsel->cgrp) {
		flags = PERF_FLAG_PID_CGROUP;
		pid = evsel->cgrp->fd;
	}

1010
fallback_missing_features:
1011 1012
	if (perf_missing_features.mmap2)
		evsel->attr.mmap2 = 0;
1013 1014 1015 1016 1017 1018
	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
1019 1020 1021
	if (verbose >= 2)
		perf_event_attr__fprintf(&evsel->attr, stderr);

1022
	for (cpu = 0; cpu < cpus->nr; cpu++) {
1023

1024
		for (thread = 0; thread < threads->nr; thread++) {
1025
			int group_fd;
S
Stephane Eranian 已提交
1026 1027 1028 1029

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

1030
			group_fd = get_group_fd(evsel, cpu, thread);
1031
retry_open:
1032
			pr_debug2("sys_perf_event_open: pid %d  cpu %d  group_fd %d  flags %#lx\n",
A
Adrian Hunter 已提交
1033 1034
				  pid, cpus->map[cpu], group_fd, flags);

1035
			FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
S
Stephane Eranian 已提交
1036
								     pid,
1037
								     cpus->map[cpu],
S
Stephane Eranian 已提交
1038
								     group_fd, flags);
1039 1040
			if (FD(evsel, cpu, thread) < 0) {
				err = -errno;
1041
				pr_debug2("sys_perf_event_open failed, error %d\n",
1042
					  err);
1043
				goto try_fallback;
1044
			}
1045
			set_rlimit = NO_CHANGE;
1046
		}
1047 1048 1049 1050
	}

	return 0;

1051
try_fallback:
1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075
	/*
	 * 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;
	}

1076 1077 1078
	if (err != -EINVAL || cpu > 0 || thread > 0)
		goto out_close;

1079 1080 1081 1082 1083
	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)) {
1084 1085 1086 1087 1088 1089 1090
		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;
	}

1091
out_close:
1092 1093 1094 1095 1096 1097 1098
	do {
		while (--thread >= 0) {
			close(FD(evsel, cpu, thread));
			FD(evsel, cpu, thread) = -1;
		}
		thread = threads->nr;
	} while (--cpu >= 0);
1099 1100 1101 1102 1103 1104 1105 1106 1107 1108
	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);
1109 1110
}

1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126
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, },
};

1127
int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1128
		     struct thread_map *threads)
1129
{
1130 1131 1132
	if (cpus == NULL) {
		/* Work around old compiler warnings about strict aliasing */
		cpus = &empty_cpu_map.map;
1133 1134
	}

1135 1136
	if (threads == NULL)
		threads = &empty_thread_map.map;
1137

1138
	return __perf_evsel__open(evsel, cpus, threads);
1139 1140
}

1141
int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
1142
			     struct cpu_map *cpus)
1143
{
1144
	return __perf_evsel__open(evsel, cpus, &empty_thread_map.map);
1145
}
1146

1147
int perf_evsel__open_per_thread(struct perf_evsel *evsel,
1148
				struct thread_map *threads)
1149
{
1150
	return __perf_evsel__open(evsel, &empty_cpu_map.map, threads);
1151
}
1152

1153 1154 1155
static int perf_evsel__parse_id_sample(const struct perf_evsel *evsel,
				       const union perf_event *event,
				       struct perf_sample *sample)
1156
{
1157
	u64 type = evsel->attr.sample_type;
1158
	const u64 *array = event->sample.array;
1159
	bool swapped = evsel->needs_swap;
1160
	union u64_swap u;
1161 1162 1163 1164

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

1165 1166 1167 1168 1169
	if (type & PERF_SAMPLE_IDENTIFIER) {
		sample->id = *array;
		array--;
	}

1170
	if (type & PERF_SAMPLE_CPU) {
1171 1172 1173 1174 1175 1176 1177 1178
		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];
1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197
		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) {
1198 1199 1200 1201 1202 1203 1204 1205 1206 1207
		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];
1208
		array--;
1209 1210 1211 1212 1213
	}

	return 0;
}

1214 1215
static inline bool overflow(const void *endp, u16 max_size, const void *offset,
			    u64 size)
1216
{
1217 1218
	return size > max_size || offset + size > endp;
}
1219

1220 1221 1222 1223 1224
#define OVERFLOW_CHECK(offset, size, max_size)				\
	do {								\
		if (overflow(endp, (max_size), (offset), (size)))	\
			return -EFAULT;					\
	} while (0)
1225

1226 1227
#define OVERFLOW_CHECK_u64(offset) \
	OVERFLOW_CHECK(offset, sizeof(u64), sizeof(u64))
1228

1229
int perf_evsel__parse_sample(struct perf_evsel *evsel, union perf_event *event,
1230
			     struct perf_sample *data)
1231
{
1232
	u64 type = evsel->attr.sample_type;
1233
	bool swapped = evsel->needs_swap;
1234
	const u64 *array;
1235 1236 1237
	u16 max_size = event->header.size;
	const void *endp = (void *)event + max_size;
	u64 sz;
1238

1239 1240 1241 1242
	/*
	 * used for cross-endian analysis. See git commit 65014ab3
	 * for why this goofiness is needed.
	 */
1243
	union u64_swap u;
1244

1245
	memset(data, 0, sizeof(*data));
1246 1247
	data->cpu = data->pid = data->tid = -1;
	data->stream_id = data->id = data->time = -1ULL;
1248
	data->period = evsel->attr.sample_period;
1249
	data->weight = 0;
1250 1251

	if (event->header.type != PERF_RECORD_SAMPLE) {
1252
		if (!evsel->attr.sample_id_all)
1253
			return 0;
1254
		return perf_evsel__parse_id_sample(evsel, event, data);
1255 1256 1257 1258
	}

	array = event->sample.array;

1259 1260 1261 1262 1263
	/*
	 * 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.
	 */
1264
	if (evsel->sample_size + sizeof(event->header) > event->header.size)
1265 1266
		return -EFAULT;

1267 1268 1269 1270 1271 1272
	data->id = -1ULL;
	if (type & PERF_SAMPLE_IDENTIFIER) {
		data->id = *array;
		array++;
	}

1273
	if (type & PERF_SAMPLE_IP) {
1274
		data->ip = *array;
1275 1276 1277 1278
		array++;
	}

	if (type & PERF_SAMPLE_TID) {
1279 1280 1281 1282 1283 1284 1285 1286 1287 1288
		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];
1289 1290 1291 1292 1293 1294 1295 1296
		array++;
	}

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

1297
	data->addr = 0;
1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313
	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) {
1314 1315 1316 1317 1318 1319 1320 1321 1322

		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];
1323 1324 1325 1326 1327 1328 1329 1330 1331
		array++;
	}

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

	if (type & PERF_SAMPLE_READ) {
1332 1333
		u64 read_format = evsel->attr.read_format;

1334
		OVERFLOW_CHECK_u64(array);
1335 1336 1337 1338 1339 1340 1341 1342
		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) {
1343
			OVERFLOW_CHECK_u64(array);
1344 1345 1346 1347 1348
			data->read.time_enabled = *array;
			array++;
		}

		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1349
			OVERFLOW_CHECK_u64(array);
1350 1351 1352 1353 1354 1355
			data->read.time_running = *array;
			array++;
		}

		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
		if (read_format & PERF_FORMAT_GROUP) {
1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366
			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;
1367
		} else {
1368
			OVERFLOW_CHECK_u64(array);
1369 1370 1371
			data->read.one.id = *array;
			array++;
		}
1372 1373 1374
	}

	if (type & PERF_SAMPLE_CALLCHAIN) {
1375
		const u64 max_callchain_nr = UINT64_MAX / sizeof(u64);
1376

1377 1378 1379
		OVERFLOW_CHECK_u64(array);
		data->callchain = (struct ip_callchain *)array++;
		if (data->callchain->nr > max_callchain_nr)
1380
			return -EFAULT;
1381 1382 1383
		sz = data->callchain->nr * sizeof(u64);
		OVERFLOW_CHECK(array, sz, max_size);
		array = (void *)array + sz;
1384 1385 1386
	}

	if (type & PERF_SAMPLE_RAW) {
1387
		OVERFLOW_CHECK_u64(array);
1388 1389 1390 1391 1392 1393 1394 1395 1396
		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];
1397
		array = (void *)array + sizeof(u32);
1398

1399 1400 1401
		OVERFLOW_CHECK(array, data->raw_size, max_size);
		data->raw_data = (void *)array;
		array = (void *)array + data->raw_size;
1402 1403
	}

1404
	if (type & PERF_SAMPLE_BRANCH_STACK) {
1405 1406
		const u64 max_branch_nr = UINT64_MAX /
					  sizeof(struct branch_entry);
1407

1408 1409
		OVERFLOW_CHECK_u64(array);
		data->branch_stack = (struct branch_stack *)array++;
1410

1411 1412
		if (data->branch_stack->nr > max_branch_nr)
			return -EFAULT;
1413
		sz = data->branch_stack->nr * sizeof(struct branch_entry);
1414 1415
		OVERFLOW_CHECK(array, sz, max_size);
		array = (void *)array + sz;
1416
	}
1417 1418

	if (type & PERF_SAMPLE_REGS_USER) {
1419
		OVERFLOW_CHECK_u64(array);
1420 1421
		data->user_regs.abi = *array;
		array++;
1422

1423
		if (data->user_regs.abi) {
1424
			u64 mask = evsel->attr.sample_regs_user;
1425

1426
			sz = hweight_long(mask) * sizeof(u64);
1427
			OVERFLOW_CHECK(array, sz, max_size);
1428
			data->user_regs.mask = mask;
1429
			data->user_regs.regs = (u64 *)array;
1430
			array = (void *)array + sz;
1431 1432 1433 1434
		}
	}

	if (type & PERF_SAMPLE_STACK_USER) {
1435 1436
		OVERFLOW_CHECK_u64(array);
		sz = *array++;
1437 1438 1439 1440

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

1441
		if (!sz) {
1442 1443
			data->user_stack.size = 0;
		} else {
1444
			OVERFLOW_CHECK(array, sz, max_size);
1445
			data->user_stack.data = (char *)array;
1446 1447
			array = (void *)array + sz;
			OVERFLOW_CHECK_u64(array);
1448
			data->user_stack.size = *array++;
1449 1450 1451
			if (WARN_ONCE(data->user_stack.size > sz,
				      "user stack dump failure\n"))
				return -EFAULT;
1452 1453 1454
		}
	}

1455 1456
	data->weight = 0;
	if (type & PERF_SAMPLE_WEIGHT) {
1457
		OVERFLOW_CHECK_u64(array);
1458 1459 1460 1461
		data->weight = *array;
		array++;
	}

1462 1463
	data->data_src = PERF_MEM_DATA_SRC_NONE;
	if (type & PERF_SAMPLE_DATA_SRC) {
1464
		OVERFLOW_CHECK_u64(array);
1465 1466 1467 1468
		data->data_src = *array;
		array++;
	}

1469 1470
	data->transaction = 0;
	if (type & PERF_SAMPLE_TRANSACTION) {
1471
		OVERFLOW_CHECK_u64(array);
1472 1473 1474 1475
		data->transaction = *array;
		array++;
	}

1476 1477
	return 0;
}
1478

1479
size_t perf_event__sample_event_size(const struct perf_sample *sample, u64 type,
1480
				     u64 read_format)
1481 1482 1483 1484 1485 1486 1487 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
{
	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);
1546
			sz = hweight_long(sample->user_regs.mask) * sizeof(u64);
1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567
			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);

1568 1569 1570
	if (type & PERF_SAMPLE_TRANSACTION)
		result += sizeof(u64);

1571 1572 1573
	return result;
}

1574
int perf_event__synthesize_sample(union perf_event *event, u64 type,
1575
				  u64 read_format,
1576 1577 1578 1579
				  const struct perf_sample *sample,
				  bool swapped)
{
	u64 *array;
1580
	size_t sz;
1581 1582 1583 1584
	/*
	 * used for cross-endian analysis. See git commit 65014ab3
	 * for why this goofiness is needed.
	 */
1585
	union u64_swap u;
1586 1587 1588

	array = event->sample.array;

1589 1590 1591 1592 1593
	if (type & PERF_SAMPLE_IDENTIFIER) {
		*array = sample->id;
		array++;
	}

1594
	if (type & PERF_SAMPLE_IP) {
1595
		*array = sample->ip;
1596 1597 1598 1599 1600 1601 1602 1603
		array++;
	}

	if (type & PERF_SAMPLE_TID) {
		u.val32[0] = sample->pid;
		u.val32[1] = sample->tid;
		if (swapped) {
			/*
1604
			 * Inverse of what is done in perf_evsel__parse_sample
1605 1606 1607 1608 1609 1610 1611 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
			 */
			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) {
			/*
1639
			 * Inverse of what is done in perf_evsel__parse_sample
1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652
			 */
			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++;
	}

1653 1654 1655 1656 1657 1658 1659 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
	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;
1716
			sz = hweight_long(sample->user_regs.mask) * sizeof(u64);
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
			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++;
	}

1744 1745 1746 1747 1748
	if (type & PERF_SAMPLE_TRANSACTION) {
		*array = sample->transaction;
		array++;
	}

1749 1750
	return 0;
}
1751

1752 1753 1754 1755 1756
struct format_field *perf_evsel__field(struct perf_evsel *evsel, const char *name)
{
	return pevent_find_field(evsel->tp_format, name);
}

1757
void *perf_evsel__rawptr(struct perf_evsel *evsel, struct perf_sample *sample,
1758 1759
			 const char *name)
{
1760
	struct format_field *field = perf_evsel__field(evsel, name);
1761 1762
	int offset;

1763 1764
	if (!field)
		return NULL;
1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778

	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)
{
1779
	struct format_field *field = perf_evsel__field(evsel, name);
1780 1781
	void *ptr;
	u64 value;
1782

1783 1784
	if (!field)
		return 0;
1785

1786
	ptr = sample->raw_data + field->offset;
1787

1788 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
	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;
1819
}
1820 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

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)

1849 1850 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
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),
1878
		bit_name(IDENTIFIER),
1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896
		{ .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);
}

1897 1898 1899 1900
int perf_evsel__fprintf(struct perf_evsel *evsel,
			struct perf_attr_details *details, FILE *fp)
{
	bool first = true;
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1901 1902
	int printed = 0;

1903
	if (details->event_group) {
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1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921
		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));
1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933

	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);
1934 1935 1936
		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);
1937 1938 1939 1940 1941 1942 1943 1944 1945
		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);
1946
		if_print(mmap2);
1947
		if_print(comm);
1948
		if_print(comm_exec);
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		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:
1965 1966 1967
	fputc('\n', fp);
	return ++printed;
}
1968 1969 1970 1971

bool perf_evsel__fallback(struct perf_evsel *evsel, int err,
			  char *msg, size_t msgsize)
{
1972
	if ((err == ENOENT || err == ENXIO || err == ENODEV) &&
1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988
	    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;

1989
		zfree(&evsel->name);
1990 1991 1992 1993 1994
		return true;
	}

	return false;
}
1995

1996
int perf_evsel__open_strerror(struct perf_evsel *evsel, struct target *target,
1997 1998 1999 2000 2001
			      int err, char *msg, size_t size)
{
	switch (err) {
	case EPERM:
	case EACCES:
2002
		return scnprintf(msg, size,
2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042
		 "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));
}