// SPDX-License-Identifier: GPL-2.0
#define _GNU_SOURCE // needed for sched.h to get sched_[gs]etaffinity and CPU_(ZERO,SET)
#include <sched.h>
#include <stdio.h>
#include <stdarg.h>
#include <unistd.h>
#include <stdlib.h>
#include <linux/perf_event.h>
#include <linux/limits.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/prctl.h>
#include <perf/cpumap.h>
#include <perf/threadmap.h>
#include <perf/evlist.h>
#include <perf/evsel.h>
#include <perf/mmap.h>
#include <perf/event.h>
#include <internal/tests.h>
#include <api/fs/fs.h>
#include "tests.h"
#include <internal/evsel.h>

#define EVENT_NUM 15
#define WAIT_COUNT 100000000UL

static int libperf_print(enum libperf_print_level level,
			 const char *fmt, va_list ap)
{
	return vfprintf(stderr, fmt, ap);
}

static int test_stat_cpu(void)
{
	struct perf_cpu_map *cpus;
	struct perf_evlist *evlist;
	struct perf_evsel *evsel, *leader;
	struct perf_event_attr attr1 = {
		.type	= PERF_TYPE_SOFTWARE,
		.config	= PERF_COUNT_SW_CPU_CLOCK,
	};
	struct perf_event_attr attr2 = {
		.type	= PERF_TYPE_SOFTWARE,
		.config	= PERF_COUNT_SW_TASK_CLOCK,
	};
	int err, idx;

	cpus = perf_cpu_map__new(NULL);
	__T("failed to create cpus", cpus);

	evlist = perf_evlist__new();
	__T("failed to create evlist", evlist);

	evsel = leader = perf_evsel__new(&attr1);
	__T("failed to create evsel1", evsel);

	perf_evlist__add(evlist, evsel);

	evsel = perf_evsel__new(&attr2);
	__T("failed to create evsel2", evsel);

	perf_evlist__add(evlist, evsel);

	perf_evlist__set_leader(evlist);
	__T("failed to set leader", leader->leader == leader);
	__T("failed to set leader", evsel->leader  == leader);

	perf_evlist__set_maps(evlist, cpus, NULL);

	err = perf_evlist__open(evlist);
	__T("failed to open evsel", err == 0);

	perf_evlist__for_each_evsel(evlist, evsel) {
		cpus = perf_evsel__cpus(evsel);

		for (idx = 0; idx < perf_cpu_map__nr(cpus); idx++) {
			struct perf_counts_values counts = { .val = 0 };

			perf_evsel__read(evsel, idx, 0, &counts);
			__T("failed to read value for evsel", counts.val != 0);
		}
	}

	perf_evlist__close(evlist);
	perf_evlist__delete(evlist);

	perf_cpu_map__put(cpus);
	return 0;
}

static int test_stat_thread(void)
{
	struct perf_counts_values counts = { .val = 0 };
	struct perf_thread_map *threads;
	struct perf_evlist *evlist;
	struct perf_evsel *evsel, *leader;
	struct perf_event_attr attr1 = {
		.type	= PERF_TYPE_SOFTWARE,
		.config	= PERF_COUNT_SW_CPU_CLOCK,
	};
	struct perf_event_attr attr2 = {
		.type	= PERF_TYPE_SOFTWARE,
		.config	= PERF_COUNT_SW_TASK_CLOCK,
	};
	int err;

	threads = perf_thread_map__new_dummy();
	__T("failed to create threads", threads);

	perf_thread_map__set_pid(threads, 0, 0);

	evlist = perf_evlist__new();
	__T("failed to create evlist", evlist);

	evsel = leader = perf_evsel__new(&attr1);
	__T("failed to create evsel1", evsel);

	perf_evlist__add(evlist, evsel);

	evsel = perf_evsel__new(&attr2);
	__T("failed to create evsel2", evsel);

	perf_evlist__add(evlist, evsel);

	perf_evlist__set_leader(evlist);
	__T("failed to set leader", leader->leader == leader);
	__T("failed to set leader", evsel->leader  == leader);

	perf_evlist__set_maps(evlist, NULL, threads);

	err = perf_evlist__open(evlist);
	__T("failed to open evsel", err == 0);

	perf_evlist__for_each_evsel(evlist, evsel) {
		perf_evsel__read(evsel, 0, 0, &counts);
		__T("failed to read value for evsel", counts.val != 0);
	}

	perf_evlist__close(evlist);
	perf_evlist__delete(evlist);

	perf_thread_map__put(threads);
	return 0;
}

static int test_stat_thread_enable(void)
{
	struct perf_counts_values counts = { .val = 0 };
	struct perf_thread_map *threads;
	struct perf_evlist *evlist;
	struct perf_evsel *evsel, *leader;
	struct perf_event_attr attr1 = {
		.type	  = PERF_TYPE_SOFTWARE,
		.config	  = PERF_COUNT_SW_CPU_CLOCK,
		.disabled = 1,
	};
	struct perf_event_attr attr2 = {
		.type	  = PERF_TYPE_SOFTWARE,
		.config	  = PERF_COUNT_SW_TASK_CLOCK,
		.disabled = 1,
	};
	int err;

	threads = perf_thread_map__new_dummy();
	__T("failed to create threads", threads);

	perf_thread_map__set_pid(threads, 0, 0);

	evlist = perf_evlist__new();
	__T("failed to create evlist", evlist);

	evsel = leader = perf_evsel__new(&attr1);
	__T("failed to create evsel1", evsel);

	perf_evlist__add(evlist, evsel);

	evsel = perf_evsel__new(&attr2);
	__T("failed to create evsel2", evsel);

	perf_evlist__add(evlist, evsel);

	perf_evlist__set_leader(evlist);
	__T("failed to set leader", leader->leader == leader);
	__T("failed to set leader", evsel->leader  == leader);

	perf_evlist__set_maps(evlist, NULL, threads);

	err = perf_evlist__open(evlist);
	__T("failed to open evsel", err == 0);

	perf_evlist__for_each_evsel(evlist, evsel) {
		perf_evsel__read(evsel, 0, 0, &counts);
		__T("failed to read value for evsel", counts.val == 0);
	}

	perf_evlist__enable(evlist);

	perf_evlist__for_each_evsel(evlist, evsel) {
		perf_evsel__read(evsel, 0, 0, &counts);
		__T("failed to read value for evsel", counts.val != 0);
	}

	perf_evlist__disable(evlist);

	perf_evlist__close(evlist);
	perf_evlist__delete(evlist);

	perf_thread_map__put(threads);
	return 0;
}

static int test_mmap_thread(void)
{
	struct perf_evlist *evlist;
	struct perf_evsel *evsel;
	struct perf_mmap *map;
	struct perf_cpu_map *cpus;
	struct perf_thread_map *threads;
	struct perf_event_attr attr = {
		.type             = PERF_TYPE_TRACEPOINT,
		.sample_period    = 1,
		.wakeup_watermark = 1,
		.disabled         = 1,
	};
	char path[PATH_MAX];
	int id, err, pid, go_pipe[2];
	union perf_event *event;
	int count = 0;

	snprintf(path, PATH_MAX, "%s/kernel/debug/tracing/events/syscalls/sys_enter_prctl/id",
		 sysfs__mountpoint());

	if (filename__read_int(path, &id)) {
		tests_failed++;
		fprintf(stderr, "error: failed to get tracepoint id: %s\n", path);
		return -1;
	}

	attr.config = id;

	err = pipe(go_pipe);
	__T("failed to create pipe", err == 0);

	fflush(NULL);

	pid = fork();
	if (!pid) {
		int i;
		char bf;

		read(go_pipe[0], &bf, 1);

		/* Generate 100 prctl calls. */
		for (i = 0; i < 100; i++)
			prctl(0, 0, 0, 0, 0);

		exit(0);
	}

	threads = perf_thread_map__new_dummy();
	__T("failed to create threads", threads);

	cpus = perf_cpu_map__dummy_new();
	__T("failed to create cpus", cpus);

	perf_thread_map__set_pid(threads, 0, pid);

	evlist = perf_evlist__new();
	__T("failed to create evlist", evlist);

	evsel = perf_evsel__new(&attr);
	__T("failed to create evsel1", evsel);
	__T("failed to set leader", evsel->leader == evsel);

	perf_evlist__add(evlist, evsel);

	perf_evlist__set_maps(evlist, cpus, threads);

	err = perf_evlist__open(evlist);
	__T("failed to open evlist", err == 0);

	err = perf_evlist__mmap(evlist, 4);
	__T("failed to mmap evlist", err == 0);

	perf_evlist__enable(evlist);

	/* kick the child and wait for it to finish */
	write(go_pipe[1], "A", 1);
	waitpid(pid, NULL, 0);

	/*
	 * There's no need to call perf_evlist__disable,
	 * monitored process is dead now.
	 */

	perf_evlist__for_each_mmap(evlist, map, false) {
		if (perf_mmap__read_init(map) < 0)
			continue;

		while ((event = perf_mmap__read_event(map)) != NULL) {
			count++;
			perf_mmap__consume(map);
		}

		perf_mmap__read_done(map);
	}

	/* calls perf_evlist__munmap/perf_evlist__close */
	perf_evlist__delete(evlist);

	perf_thread_map__put(threads);
	perf_cpu_map__put(cpus);

	/*
	 * The generated prctl calls should match the
	 * number of events in the buffer.
	 */
	__T("failed count", count == 100);

	return 0;
}

static int test_mmap_cpus(void)
{
	struct perf_evlist *evlist;
	struct perf_evsel *evsel;
	struct perf_mmap *map;
	struct perf_cpu_map *cpus;
	struct perf_event_attr attr = {
		.type             = PERF_TYPE_TRACEPOINT,
		.sample_period    = 1,
		.wakeup_watermark = 1,
		.disabled         = 1,
	};
	cpu_set_t saved_mask;
	char path[PATH_MAX];
	int id, err, tmp;
	struct perf_cpu cpu;
	union perf_event *event;
	int count = 0;

	snprintf(path, PATH_MAX, "%s/kernel/debug/tracing/events/syscalls/sys_enter_prctl/id",
		 sysfs__mountpoint());

	if (filename__read_int(path, &id)) {
		fprintf(stderr, "error: failed to get tracepoint id: %s\n", path);
		return -1;
	}

	attr.config = id;

	cpus = perf_cpu_map__new(NULL);
	__T("failed to create cpus", cpus);

	evlist = perf_evlist__new();
	__T("failed to create evlist", evlist);

	evsel = perf_evsel__new(&attr);
	__T("failed to create evsel1", evsel);
	__T("failed to set leader", evsel->leader == evsel);

	perf_evlist__add(evlist, evsel);

	perf_evlist__set_maps(evlist, cpus, NULL);

	err = perf_evlist__open(evlist);
	__T("failed to open evlist", err == 0);

	err = perf_evlist__mmap(evlist, 4);
	__T("failed to mmap evlist", err == 0);

	perf_evlist__enable(evlist);

	err = sched_getaffinity(0, sizeof(saved_mask), &saved_mask);
	__T("sched_getaffinity failed", err == 0);

	perf_cpu_map__for_each_cpu(cpu, tmp, cpus) {
		cpu_set_t mask;

		CPU_ZERO(&mask);
		CPU_SET(cpu.cpu, &mask);

		err = sched_setaffinity(0, sizeof(mask), &mask);
		__T("sched_setaffinity failed", err == 0);

		prctl(0, 0, 0, 0, 0);
	}

	err = sched_setaffinity(0, sizeof(saved_mask), &saved_mask);
	__T("sched_setaffinity failed", err == 0);

	perf_evlist__disable(evlist);

	perf_evlist__for_each_mmap(evlist, map, false) {
		if (perf_mmap__read_init(map) < 0)
			continue;

		while ((event = perf_mmap__read_event(map)) != NULL) {
			count++;
			perf_mmap__consume(map);
		}

		perf_mmap__read_done(map);
	}

	/* calls perf_evlist__munmap/perf_evlist__close */
	perf_evlist__delete(evlist);

	/*
	 * The generated prctl events should match the
	 * number of cpus or be bigger (we are system-wide).
	 */
	__T("failed count", count >= perf_cpu_map__nr(cpus));

	perf_cpu_map__put(cpus);

	return 0;
}

static double display_error(long long average,
			    long long high,
			    long long low,
			    long long expected)
{
	double error;

	error = (((double)average - expected) / expected) * 100.0;

	__T_VERBOSE("   Expected: %lld\n", expected);
	__T_VERBOSE("   High: %lld   Low:  %lld   Average:  %lld\n",
		    high, low, average);

	__T_VERBOSE("   Average Error = %.2f%%\n", error);

	return error;
}

static int test_stat_multiplexing(void)
{
	struct perf_counts_values expected_counts = { .val = 0 };
	struct perf_counts_values counts[EVENT_NUM] = {{ .val = 0 },};
	struct perf_thread_map *threads;
	struct perf_evlist *evlist;
	struct perf_evsel *evsel;
	struct perf_event_attr attr = {
		.type	     = PERF_TYPE_HARDWARE,
		.config	     = PERF_COUNT_HW_INSTRUCTIONS,
		.read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
			       PERF_FORMAT_TOTAL_TIME_RUNNING,
		.disabled    = 1,
	};
	int err, i, nonzero = 0;
	unsigned long count;
	long long max = 0, min = 0, avg = 0;
	double error = 0.0;
	s8 scaled = 0;

	/* read for non-multiplexing event count */
	threads = perf_thread_map__new_dummy();
	__T("failed to create threads", threads);

	perf_thread_map__set_pid(threads, 0, 0);

	evsel = perf_evsel__new(&attr);
	__T("failed to create evsel", evsel);

	err = perf_evsel__open(evsel, NULL, threads);
	__T("failed to open evsel", err == 0);

	err = perf_evsel__enable(evsel);
	__T("failed to enable evsel", err == 0);

	/* wait loop */
	count = WAIT_COUNT;
	while (count--)
		;

	perf_evsel__read(evsel, 0, 0, &expected_counts);
	__T("failed to read value for evsel", expected_counts.val != 0);
	__T("failed to read non-multiplexing event count",
	    expected_counts.ena == expected_counts.run);

	err = perf_evsel__disable(evsel);
	__T("failed to enable evsel", err == 0);

	perf_evsel__close(evsel);
	perf_evsel__delete(evsel);

	perf_thread_map__put(threads);

	/* read for multiplexing event count */
	threads = perf_thread_map__new_dummy();
	__T("failed to create threads", threads);

	perf_thread_map__set_pid(threads, 0, 0);

	evlist = perf_evlist__new();
	__T("failed to create evlist", evlist);

	for (i = 0; i < EVENT_NUM; i++) {
		evsel = perf_evsel__new(&attr);
		__T("failed to create evsel", evsel);

		perf_evlist__add(evlist, evsel);
	}
	perf_evlist__set_maps(evlist, NULL, threads);

	err = perf_evlist__open(evlist);
	__T("failed to open evsel", err == 0);

	perf_evlist__enable(evlist);

	/* wait loop */
	count = WAIT_COUNT;
	while (count--)
		;

	i = 0;
	perf_evlist__for_each_evsel(evlist, evsel) {
		perf_evsel__read(evsel, 0, 0, &counts[i]);
		__T("failed to read value for evsel", counts[i].val != 0);
		i++;
	}

	perf_evlist__disable(evlist);

	min = counts[0].val;
	for (i = 0; i < EVENT_NUM; i++) {
		__T_VERBOSE("Event %2d -- Raw count = %lu, run = %lu, enable = %lu\n",
			    i, counts[i].val, counts[i].run, counts[i].ena);

		perf_counts_values__scale(&counts[i], true, &scaled);
		if (scaled == 1) {
			__T_VERBOSE("\t Scaled count = %lu (%.2lf%%, %lu/%lu)\n",
				    counts[i].val,
				    (double)counts[i].run / (double)counts[i].ena * 100.0,
				    counts[i].run, counts[i].ena);
		} else if (scaled == -1) {
			__T_VERBOSE("\t Not Running\n");
		} else {
			__T_VERBOSE("\t Not Scaling\n");
		}

		if (counts[i].val > max)
			max = counts[i].val;

		if (counts[i].val < min)
			min = counts[i].val;

		avg += counts[i].val;

		if (counts[i].val != 0)
			nonzero++;
	}

	if (nonzero != 0)
		avg = avg / nonzero;
	else
		avg = 0;

	error = display_error(avg, max, min, expected_counts.val);

	__T("Error out of range!", ((error <= 1.0) && (error >= -1.0)));

	perf_evlist__close(evlist);
	perf_evlist__delete(evlist);

	perf_thread_map__put(threads);

	return 0;
}

int test_evlist(int argc, char **argv)
{
	__T_START;

	libperf_init(libperf_print);

	test_stat_cpu();
	test_stat_thread();
	test_stat_thread_enable();
	test_mmap_thread();
	test_mmap_cpus();
	test_stat_multiplexing();

	__T_END;
	return tests_failed == 0 ? 0 : -1;
}