builtin-top.c

		if (callchain_register_param(&callchain_param) < 0) {
			ui__error("Can't register callchain params.\n");
			return -EINVAL;
		}
	}

	return 0;
}

static int __cmd_top(struct perf_top *top)
{
	pthread_t thread;
	int ret;
	/*
	 * FIXME: perf_session__new should allow passing a O_MMAP, so that all this
	 * mmap reading, etc is encapsulated in it. Use O_WRONLY for now.
	 */
	top->session = perf_session__new(NULL, O_WRONLY, false, false, NULL);
	if (top->session == NULL)
		return -ENOMEM;

	ret = perf_top__setup_sample_type(top);
	if (ret)
		goto out_delete;

	if (perf_target__has_task(&top->target))
		perf_event__synthesize_thread_map(&top->tool, top->evlist->threads,
						  perf_event__process,
						  &top->session->host_machine);
	else
		perf_event__synthesize_threads(&top->tool, perf_event__process,
					       &top->session->host_machine);
	perf_top__start_counters(top);
	top->session->evlist = top->evlist;
	perf_session__update_sample_type(top->session);

	/* Wait for a minimal set of events before starting the snapshot */
	poll(top->evlist->pollfd, top->evlist->nr_fds, 100);

	perf_top__mmap_read(top);

	if (pthread_create(&thread, NULL, (use_browser > 0 ? display_thread_tui :
							    display_thread), top)) {
		ui__error("Could not create display thread.\n");
		exit(-1);
	}

	if (top->realtime_prio) {
		struct sched_param param;

		param.sched_priority = top->realtime_prio;
		if (sched_setscheduler(0, SCHED_FIFO, &param)) {
			ui__error("Could not set realtime priority.\n");
			exit(-1);
		}
	}

	while (1) {
		u64 hits = top->samples;

		perf_top__mmap_read(top);

		if (hits == top->samples)
			ret = poll(top->evlist->pollfd, top->evlist->nr_fds, 100);
	}

out_delete:
	perf_session__delete(top->session);
	top->session = NULL;

	return 0;
}

static int
parse_callchain_opt(const struct option *opt, const char *arg, int unset)
{
	struct perf_top *top = (struct perf_top *)opt->value;
	char *tok, *tok2;
	char *endptr;

	/*
	 * --no-call-graph
	 */
	if (unset) {
		top->dont_use_callchains = true;
		return 0;
	}

	symbol_conf.use_callchain = true;

	if (!arg)
		return 0;

	tok = strtok((char *)arg, ",");
	if (!tok)
		return -1;

	/* get the output mode */
	if (!strncmp(tok, "graph", strlen(arg)))
		callchain_param.mode = CHAIN_GRAPH_ABS;

	else if (!strncmp(tok, "flat", strlen(arg)))
		callchain_param.mode = CHAIN_FLAT;

	else if (!strncmp(tok, "fractal", strlen(arg)))
		callchain_param.mode = CHAIN_GRAPH_REL;

	else if (!strncmp(tok, "none", strlen(arg))) {
		callchain_param.mode = CHAIN_NONE;
		symbol_conf.use_callchain = false;

		return 0;
	} else
		return -1;

	/* get the min percentage */
	tok = strtok(NULL, ",");
	if (!tok)
		goto setup;

	callchain_param.min_percent = strtod(tok, &endptr);
	if (tok == endptr)
		return -1;

	/* get the print limit */
	tok2 = strtok(NULL, ",");
	if (!tok2)
		goto setup;

	if (tok2[0] != 'c') {
		callchain_param.print_limit = strtod(tok2, &endptr);
		tok2 = strtok(NULL, ",");
		if (!tok2)
			goto setup;
	}

	/* get the call chain order */
	if (!strcmp(tok2, "caller"))
		callchain_param.order = ORDER_CALLER;
	else if (!strcmp(tok2, "callee"))
		callchain_param.order = ORDER_CALLEE;
	else
		return -1;
setup:
	if (callchain_register_param(&callchain_param) < 0) {
		fprintf(stderr, "Can't register callchain params\n");
		return -1;
	}
	return 0;
}

static const char * const top_usage[] = {
	"perf top [<options>]",
	NULL
};

int cmd_top(int argc, const char **argv, const char *prefix __used)
{
	struct perf_evsel *pos;
	int status;
	char errbuf[BUFSIZ];
	struct perf_top top = {
		.count_filter	     = 5,
		.delay_secs	     = 2,
		.freq		     = 4000, /* 4 KHz */
		.mmap_pages	     = 128,
		.sym_pcnt_filter     = 5,
		.target		     = {
			.uses_mmap   = true,
		},
	};
	char callchain_default_opt[] = "fractal,0.5,callee";
	const struct option options[] = {
	OPT_CALLBACK('e', "event", &top.evlist, "event",
		     "event selector. use 'perf list' to list available events",
		     parse_events_option),
	OPT_INTEGER('c', "count", &top.default_interval,
		    "event period to sample"),
	OPT_STRING('p', "pid", &top.target.pid, "pid",
		    "profile events on existing process id"),
	OPT_STRING('t', "tid", &top.target.tid, "tid",
		    "profile events on existing thread id"),
	OPT_BOOLEAN('a', "all-cpus", &top.target.system_wide,
			    "system-wide collection from all CPUs"),
	OPT_STRING('C', "cpu", &top.target.cpu_list, "cpu",
		    "list of cpus to monitor"),
	OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
		   "file", "vmlinux pathname"),
	OPT_BOOLEAN('K', "hide_kernel_symbols", &top.hide_kernel_symbols,
		    "hide kernel symbols"),
	OPT_UINTEGER('m', "mmap-pages", &top.mmap_pages, "number of mmap data pages"),
	OPT_INTEGER('r', "realtime", &top.realtime_prio,
		    "collect data with this RT SCHED_FIFO priority"),
	OPT_INTEGER('d', "delay", &top.delay_secs,
		    "number of seconds to delay between refreshes"),
	OPT_BOOLEAN('D', "dump-symtab", &top.dump_symtab,
			    "dump the symbol table used for profiling"),
	OPT_INTEGER('f', "count-filter", &top.count_filter,
		    "only display functions with more events than this"),
	OPT_BOOLEAN('g', "group", &top.group,
			    "put the counters into a counter group"),
	OPT_BOOLEAN('i', "inherit", &top.inherit,
		    "child tasks inherit counters"),
	OPT_STRING(0, "sym-annotate", &top.sym_filter, "symbol name",
		    "symbol to annotate"),
	OPT_BOOLEAN('z', "zero", &top.zero,
		    "zero history across updates"),
	OPT_INTEGER('F', "freq", &top.freq,
		    "profile at this frequency"),
	OPT_INTEGER('E', "entries", &top.print_entries,
		    "display this many functions"),
	OPT_BOOLEAN('U', "hide_user_symbols", &top.hide_user_symbols,
		    "hide user symbols"),
	OPT_BOOLEAN(0, "tui", &top.use_tui, "Use the TUI interface"),
	OPT_BOOLEAN(0, "stdio", &top.use_stdio, "Use the stdio interface"),
	OPT_INCR('v', "verbose", &verbose,
		    "be more verbose (show counter open errors, etc)"),
	OPT_STRING('s', "sort", &sort_order, "key[,key2...]",
		   "sort by key(s): pid, comm, dso, symbol, parent"),
	OPT_BOOLEAN('n', "show-nr-samples", &symbol_conf.show_nr_samples,
		    "Show a column with the number of samples"),
	OPT_CALLBACK_DEFAULT('G', "call-graph", &top, "output_type,min_percent, call_order",
		     "Display callchains using output_type (graph, flat, fractal, or none), min percent threshold and callchain order. "
		     "Default: fractal,0.5,callee", &parse_callchain_opt,
		     callchain_default_opt),
	OPT_BOOLEAN(0, "show-total-period", &symbol_conf.show_total_period,
		    "Show a column with the sum of periods"),
	OPT_STRING(0, "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
		   "only consider symbols in these dsos"),
	OPT_STRING(0, "comms", &symbol_conf.comm_list_str, "comm[,comm...]",
		   "only consider symbols in these comms"),
	OPT_STRING(0, "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",
		   "only consider these symbols"),
	OPT_BOOLEAN(0, "source", &symbol_conf.annotate_src,
		    "Interleave source code with assembly code (default)"),
	OPT_BOOLEAN(0, "asm-raw", &symbol_conf.annotate_asm_raw,
		    "Display raw encoding of assembly instructions (default)"),
	OPT_STRING('M', "disassembler-style", &disassembler_style, "disassembler style",
		   "Specify disassembler style (e.g. -M intel for intel syntax)"),
	OPT_STRING('u', "uid", &top.target.uid_str, "user", "user to profile"),
	OPT_END()
	};

	top.evlist = perf_evlist__new(NULL, NULL);
	if (top.evlist == NULL)
		return -ENOMEM;

	symbol_conf.exclude_other = false;

	argc = parse_options(argc, argv, options, top_usage, 0);
	if (argc)
		usage_with_options(top_usage, options);

	if (sort_order == default_sort_order)
		sort_order = "dso,symbol";

	setup_sorting(top_usage, options);

	if (top.use_stdio)
		use_browser = 0;
	else if (top.use_tui)
		use_browser = 1;

	setup_browser(false);

	status = perf_target__validate(&top.target);
	if (status) {
		perf_target__strerror(&top.target, status, errbuf, BUFSIZ);
		ui__warning("%s", errbuf);
	}

	status = perf_target__parse_uid(&top.target);
	if (status) {
		int saved_errno = errno;

		perf_target__strerror(&top.target, status, errbuf, BUFSIZ);
		ui__error("%s", errbuf);

		status = -saved_errno;
		goto out_delete_evlist;
	}

	if (perf_target__none(&top.target))
		top.target.system_wide = true;

	if (perf_evlist__create_maps(top.evlist, &top.target) < 0)
		usage_with_options(top_usage, options);

	if (!top.evlist->nr_entries &&
	    perf_evlist__add_default(top.evlist) < 0) {
		ui__error("Not enough memory for event selector list\n");
		return -ENOMEM;
	}

	symbol_conf.nr_events = top.evlist->nr_entries;

	if (top.delay_secs < 1)
		top.delay_secs = 1;

	/*
	 * User specified count overrides default frequency.
	 */
	if (top.default_interval)
		top.freq = 0;
	else if (top.freq) {
		top.default_interval = top.freq;
	} else {
		ui__error("frequency and count are zero, aborting\n");
		exit(EXIT_FAILURE);
	}

	list_for_each_entry(pos, &top.evlist->entries, node) {
		/*
		 * Fill in the ones not specifically initialized via -c:
		 */
		if (!pos->attr.sample_period)
			pos->attr.sample_period = top.default_interval;
	}

	top.sym_evsel = list_entry(top.evlist->entries.next, struct perf_evsel, node);

	symbol_conf.priv_size = sizeof(struct annotation);

	symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);
	if (symbol__init() < 0)
		return -1;

	sort_entry__setup_elide(&sort_dso, symbol_conf.dso_list, "dso", stdout);
	sort_entry__setup_elide(&sort_comm, symbol_conf.comm_list, "comm", stdout);
	sort_entry__setup_elide(&sort_sym, symbol_conf.sym_list, "symbol", stdout);

	/*
	 * Avoid annotation data structures overhead when symbols aren't on the
	 * sort list.
	 */
	top.sort_has_symbols = sort_sym.list.next != NULL;

	get_term_dimensions(&top.winsize);
	if (top.print_entries == 0) {
		struct sigaction act = {
			.sa_sigaction = perf_top__sig_winch,
			.sa_flags     = SA_SIGINFO,
		};
		perf_top__update_print_entries(&top);
		sigaction(SIGWINCH, &act, NULL);
	}

	status = __cmd_top(&top);

out_delete_evlist:
	perf_evlist__delete(top.evlist);

	return status;
}