tools: perf: add perf-periodic

Add the 'periodic' command to perf. This allows collection
of counters at a specified interval.

Change-Id: I4e42ac3f21cbdf2c196dbd01d31e6dc6051efd7e
Signed-off-by: Neil Leeder <nleeder@codeaurora.org>
diff --git a/tools/perf/builtin-periodic.c b/tools/perf/builtin-periodic.c
new file mode 100644
index 0000000..70a0e2b
--- /dev/null
+++ b/tools/perf/builtin-periodic.c
@@ -0,0 +1,483 @@
+/*
+ * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+/*
+ *	A very simple perf program to periodically print the performance
+ *	counter reqested on the command line to standard out at the rate
+ *	specified.
+ *
+ *	This is valuable for showing the output in a simple plot or
+ *	exporting the counter data for post processing.  No attempt
+ *	to process the data is made.
+ *
+ *	Scaling is not supported, use only as many counters as are
+ *	provided by the hardware.
+ *
+ *	Math functions are support to combine counter results by using
+ *	the -m flag.
+ *
+ *	The -r -w flags supports user signalling for input. This assumes
+ *	that a pipe/fifo is needed so the -rw cmd line arg is a string
+ *	that is the name of the named pipe to open for read/write.  User
+ *	sends data on the read pipe to the process to collect a sample.
+ *	Commands are also supported on the pipe.
+ *
+ */
+
+#include "perf.h"
+#include "builtin.h"
+#include "util/util.h"
+#include "util/parse-options.h"
+#include "util/parse-events.h"
+#include "util/event.h"
+#include "util/evsel.h"
+#include "util/evlist.h"
+#include "util/debug.h"
+#include "util/header.h"
+#include "util/cpumap.h"
+#include "util/thread.h"
+#include <signal.h>
+#include <sys/types.h>
+
+#define PERF_PERIODIC_ERROR -1
+
+/* number of pieces of data on each read. */
+#define DATA_SIZE 2
+
+#define DEFAULT_FIFO_NAME "xxbadFiFo"
+#define MAX_NAMELEN 50
+
+struct perf_evlist *evsel_list;
+
+/*
+ * command line variables and settings
+ * Default to current process, no_inherit, process
+ */
+static pid_t target_pid = -1; /* all */
+static bool system_wide;
+static int cpumask = -1;  /* all */
+static int ncounts;
+static int ms_sleep = 1000;  /* 1 second */
+static char const *operations = "nnnnnnnnnnnnnnnn";  /* nop */
+static bool math_enabled;
+static bool calc_delta;
+static double old_accum, accum;
+static int math_op_index;
+static char const *wfifo_name = DEFAULT_FIFO_NAME;
+static char const *rfifo_name = DEFAULT_FIFO_NAME;
+static bool use_fifo;
+static bool is_ratio;
+static FILE *fd_in, *fd_out;
+
+static FILE *tReadFifo, *tWriteFifo;
+
+/*
+ * Raw results from perf, we track the current value and
+ * the old value.
+ */
+struct perf_raw_results_s {
+	u64 values;
+	u64 old_value;
+};
+
+/*
+ * Everything we need to support a perf counter across multiple
+ * CPUs.  We need to support multiple file descriptors (perf_fd)
+ * because perf requires a fd per counter, so 1 per core enabled.
+ *
+ * Raw results values are calculated across all the cores as they
+ * are read.
+ */
+struct perf_setup_s {
+	int event_index;
+	struct perf_event_attr *attr;
+	int perf_fd[MAX_NR_CPUS];
+	pid_t pid;
+	int cpu;
+	int flags;
+	int group;
+	struct perf_raw_results_s data;
+	struct perf_raw_results_s totals;
+	struct perf_raw_results_s output;
+};
+
+static void do_cleanup(void)
+{
+	if (fd_in) {
+		if (0 != fclose(fd_in))
+			error("Error closing fd_in\n");
+	}
+	if (fd_out) {
+		if (0 != fclose(fd_out))
+			error("Error closing fd_out\n");
+	}
+	if (use_fifo) {
+		if (0 != unlink(rfifo_name))
+			error("Error unlinking rfifo\n");
+		if (0 != unlink(wfifo_name))
+			error("Error unlinking wfifo\n");
+	}
+}
+
+/*
+ * Unexpected signal for error indication, cleanup
+ */
+static int sig_dummy;
+static void sig_do_cleanup(int sig)
+{
+	sig_dummy = sig;
+	do_cleanup();
+	exit(0);
+}
+
+#define PERIODIC_MAX_STRLEN 100
+/*
+ * Delay for either a timed period or the wait on the read_fifo
+ */
+static void delay(unsigned long milli)
+{
+	char tmp_stg[PERIODIC_MAX_STRLEN];
+	int done;
+	int ret;
+
+	if (use_fifo) {
+		do {
+			done = true;
+			ret = fscanf(tReadFifo, "%s", tmp_stg);
+			if (ret == 0)
+				return;
+			/*
+			 * Look for a command request, and if we get a command
+			 * Need to process and then wait again w/o sending data.
+			 */
+			if (strncmp(tmp_stg, "PID", strnlen(tmp_stg,
+				PERIODIC_MAX_STRLEN)) == 0) {
+				fprintf(fd_out, " %u\n", getpid());
+				fflush(fd_out);
+				done = false;
+			} else if (strncmp(tmp_stg, "EXIT",
+					strnlen(tmp_stg, PERIODIC_MAX_STRLEN))
+						== 0) {
+				do_cleanup();
+				exit(0);
+			}
+
+		} while (done != true);
+	} else
+		usleep(milli*1000);
+}
+
+/*
+ * Create a perf counter event.
+ * Some interesting behaviour that is not documented anywhere else:
+ * the CPU will not work if out of range.
+ * The CPU will only work for a single CPU, so to collect the counts
+ * on the system in SMP based systems a counter needs to be created
+ * for each CPU.
+ */
+static int create_perf_counter(struct perf_setup_s *p)
+{
+	struct cpu_map *cpus;
+	int cpu;
+
+	cpus = cpu_map__new(NULL);
+	if (p == NULL)
+		return PERF_PERIODIC_ERROR;
+	for (cpu = 0; cpu < cpus->nr; cpu++) {
+		p->perf_fd[cpu] = sys_perf_event_open(p->attr, target_pid, cpu,
+					-1, 0);
+		if (p->perf_fd[cpu] < 0)
+			return PERF_PERIODIC_ERROR;
+	}
+	return 0;
+}
+
+/*
+ * Perf init setup
+ */
+static int perf_setup_init(struct perf_setup_s *p)
+{
+	if (p == NULL)
+		return PERF_PERIODIC_ERROR;
+
+	bzero(p, sizeof(struct perf_setup_s));
+	p->group = -1;
+	p->flags = 0;
+
+	p->output.values = 0;
+	p->output.old_value = 0;
+	p->data.values = 0;
+	p->data.old_value = 0;
+	p->totals.old_value = 0;
+	p->totals.values = 0;
+
+	return 0;
+}
+
+/*
+ * Read in ALL the performance counters configured for the CPU,
+ * one performance monitor per core that was configured during
+ * "all" mode
+ */
+static int perf_setup_read(struct perf_setup_s *p)
+{
+	u64 data[DATA_SIZE];
+	int i, status;
+
+	p->totals.values = 0;
+	p->data.values = 0;
+	for (i = 0; i < MAX_NR_CPUS; i++) {
+		if (p->perf_fd[i] == 0)
+			continue;
+		status = read(p->perf_fd[i], &data, sizeof(data));
+		p->data.values += data[0];
+		p->totals.values += data[0];
+	}
+
+	/*
+	 * Normally we show totals, we want to support
+	 * showing deltas from the previous value so external apps do not have
+	 * to do this...
+	 */
+	if (calc_delta) {
+		p->output.values = p->data.values - p->data.old_value;
+		p->data.old_value = p->data.values;
+	} else
+		p->output.values = p->totals.values;
+	return 0;
+}
+
+static int perf_setup_show(struct perf_setup_s *p)
+{
+	if (p == NULL)
+		return PERF_PERIODIC_ERROR;
+	fprintf(fd_out, " %llu", p->output.values);
+	return 0;
+}
+
+
+static const char * const periodic_usage[] = {
+	"perf periodic [<options>]",
+	NULL
+};
+
+static const struct option options[] = {
+	OPT_CALLBACK('e', "event", &evsel_list, "event",
+	"event selector. use 'perf list' to list available events",
+	 parse_events),
+	OPT_STRING('m', "math-operations", &operations, "nnnnnn",
+	"math operation to perform on values collected asmd in order"),
+	OPT_STRING('r', "readpipe", &rfifo_name, "xxbadFiFo",
+	"wait for a user input fifo - will be created"),
+	OPT_STRING('w', "writepipe", &wfifo_name, "xxbadFifo",
+	"write data out on this pipe - pipe is created"),
+	OPT_INTEGER('i', "increment", &ncounts,
+	"number of times periods to count/iterate (default 0-forever)"),
+	OPT_INTEGER('p', "pid", &target_pid,
+	"stat events on existing process id"),
+	OPT_INTEGER('c', "cpumask", &cpumask,
+	"cpumask to enable counters, default all (-1)"),
+	OPT_INTEGER('s', "sleep", &ms_sleep,
+	"how long to sleep in ms between each sample (default 1000)"),
+	OPT_BOOLEAN('a', "all-cpus", &system_wide,
+	"system-wide collection from all CPUs overrides cpumask"),
+	OPT_BOOLEAN('d', "delta", &calc_delta,
+	"calculate and display the delta values math funcs will use delta"),
+	OPT_INCR('v', "verbose", &verbose,
+	"be more verbose (show counter open errors, etc)"),
+	OPT_END()
+};
+
+/*
+ * After every period we reset any math that was performed.
+ */
+static void reset_math(void)
+{
+	math_op_index = 0;
+	old_accum = accum;
+	accum = 0;
+}
+
+static void do_math_op(struct perf_setup_s *p)
+{
+	if (!math_enabled)
+		return;
+	switch (operations[math_op_index++]) {
+	case 'm':
+		accum *= (double)p->output.values; break;
+	case 'a':
+		accum += (double)p->output.values; break;
+	case 's':
+		accum -= (double)p->output.values; break;
+	case 'd':
+		accum /= (double)p->output.values; break;
+	case 'z':
+		accum =  0; break;
+	case 't':
+		accum =  (double)p->output.values; break; /*transfer*/
+	case 'T':
+		accum +=  old_accum; break; /*total*/
+	case 'i':	/* ignore */
+	default:
+		break;
+	}
+}
+
+int cmd_periodic(int argc, const char **argv, const char *prefix __used)
+{
+	int status = 0;
+	int c, i;
+	struct perf_setup_s *p[MAX_COUNTERS];
+	struct perf_evsel *counter;
+	FILE *fp;
+	int nr_counters = 0;
+
+	evsel_list = perf_evlist__new(NULL, NULL);
+	if (evsel_list == NULL)
+		return -ENOMEM;
+
+	argc = parse_options(argc, argv, options, periodic_usage,
+		PARSE_OPT_STOP_AT_NON_OPTION);
+
+	if (system_wide)
+		cpumask = -1;
+
+	/*
+	 * The r & w option redirects stdout to a newly created pipe and
+	 * waits for input on the read pipe before continuing
+	 */
+	fd_in = stdin;
+	fd_out = stdout;
+	if (strncmp(rfifo_name, DEFAULT_FIFO_NAME,
+				strnlen(rfifo_name, MAX_NAMELEN))) {
+		fp = fopen(rfifo_name, "r");
+		if (fp != NULL) {
+			fclose(fp);
+			remove(rfifo_name);
+		}
+		if (mkfifo(rfifo_name, 0777) == -1) {
+			error("Could not open read fifo\n");
+			do_cleanup();
+			return PERF_PERIODIC_ERROR;
+		}
+		tReadFifo = fopen(rfifo_name, "r+");
+		if (tReadFifo == 0) {
+			do_cleanup();
+			error("Could not open read fifo file\n");
+			return PERF_PERIODIC_ERROR;
+		}
+		use_fifo = true;
+	}
+	if (strncmp(wfifo_name, DEFAULT_FIFO_NAME,
+				strnlen(wfifo_name, MAX_NAMELEN)))  {
+		fp = fopen(wfifo_name, "r");
+		if (fp != NULL) {
+			fclose(fp);
+			remove(wfifo_name);
+		}
+		if (mkfifo(wfifo_name, 0777) == -1) {
+			do_cleanup();
+			error("Could not open write fifo\n");
+			return PERF_PERIODIC_ERROR;
+		}
+		fd_out = fopen(wfifo_name, "w+");
+		if (fd_out == 0) {
+			do_cleanup();
+			error("Could not open write fifo file\n");
+			return PERF_PERIODIC_ERROR;
+		}
+		tWriteFifo = fd_out;
+	}
+
+	math_enabled = (operations[0] != 'n');
+
+	/*
+	 * If we don't ignore SIG_PIPE then when the other side
+	 * of a pipe closes we shutdown too...
+	 */
+	signal(SIGPIPE, SIG_IGN);
+	signal(SIGINT, sig_do_cleanup);
+	signal(SIGQUIT, sig_do_cleanup);
+	signal(SIGKILL, sig_do_cleanup);
+	signal(SIGTERM, sig_do_cleanup);
+
+	i = 0;
+	list_for_each_entry(counter, &evsel_list->entries, node) {
+		p[i] = malloc(sizeof(struct perf_setup_s));
+		if (p[i] == NULL) {
+			error("Error allocating perf_setup_s\n");
+			do_cleanup();
+			return PERF_PERIODIC_ERROR;
+		}
+		bzero(p[i], sizeof(struct perf_setup_s));
+		perf_setup_init(p[i]);
+		p[i]->attr = &(counter->attr);
+		p[i]->event_index = counter->idx;
+		if (create_perf_counter(p[i]) < 0) {
+			do_cleanup();
+			die("Not all events could be opened.\n");
+			return PERF_PERIODIC_ERROR;
+		}
+		i++;
+		nr_counters++;
+	}
+	i = 0;
+	while (1) {
+
+		/*
+		 * Wait first otherwise single sample will print w/o signal
+		 * when using the -u (user signal) flag
+		 */
+		delay(ms_sleep);
+
+		/*
+		 * Do the collection, read and then perform any math operations
+		 */
+		for (c = 0; c < nr_counters; c++) {
+			status = perf_setup_read(p[c]);
+			do_math_op(p[c]);
+		}
+
+		/*
+		 * After all collection and math, we perform one last math
+		 * to allow totaling, if enabled etc, then either printout
+		 * a single float value when the math is enabled or ...
+		 */
+		if (math_enabled) {
+			do_math_op(p[c]);
+			if (is_ratio)
+				fprintf(fd_out, "%#f\n", accum*100);
+			else
+				fprintf(fd_out, "%#f\n", accum);
+		} else {
+			/*
+			 * ... print out one integer value for each counter
+			 */
+			for (c = 0; c < nr_counters; c++)
+				status = perf_setup_show(p[c]);
+			fprintf(fd_out, "\n");
+		}
+
+		/*
+		 * Did the user give us an iteration count?
+		 */
+		if ((ncounts != 0) && (++i >= ncounts))
+			break;
+		reset_math();
+		fflush(fd_out); /* make sure data is flushed out the pipe*/
+	}
+
+	do_cleanup();
+
+	return status;
+}