[linux-2.6-block.git] / tools / perf / tests / code-reading.c

#include <sys/types.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <inttypes.h>
#include <ctype.h>
#include <string.h>

#include "parse-events.h"
#include "evlist.h"
#include "evsel.h"
#include "thread_map.h"
#include "cpumap.h"
#include "machine.h"
#include "event.h"
#include "thread.h"

#include "tests.h"

#define BUFSZ	1024
#define READLEN	128

struct state {
	u64 done[1024];
	size_t done_cnt;
};

static unsigned int hex(char c)
{
	if (c >= '0' && c <= '9')
		return c - '0';
	if (c >= 'a' && c <= 'f')
		return c - 'a' + 10;
	return c - 'A' + 10;
}

static void read_objdump_line(const char *line, size_t line_len, void **buf,
			      size_t *len)
{
	const char *p;
	size_t i;

	/* Skip to a colon */
	p = strchr(line, ':');
	if (!p)
		return;
	i = p + 1 - line;

	/* Read bytes */
	while (*len) {
		char c1, c2;

		/* Skip spaces */
		for (; i < line_len; i++) {
			if (!isspace(line[i]))
				break;
		}
		/* Get 2 hex digits */
		if (i >= line_len || !isxdigit(line[i]))
			break;
		c1 = line[i++];
		if (i >= line_len || !isxdigit(line[i]))
			break;
		c2 = line[i++];
		/* Followed by a space */
		if (i < line_len && line[i] && !isspace(line[i]))
			break;
		/* Store byte */
		*(unsigned char *)*buf = (hex(c1) << 4) | hex(c2);
		*buf += 1;
		*len -= 1;
	}
}

static int read_objdump_output(FILE *f, void **buf, size_t *len)
{
	char *line = NULL;
	size_t line_len;
	ssize_t ret;
	int err = 0;

	while (1) {
		ret = getline(&line, &line_len, f);
		if (feof(f))
			break;
		if (ret < 0) {
			pr_debug("getline failed\n");
			err = -1;
			break;
		}
		read_objdump_line(line, ret, buf, len);
	}

	free(line);

	return err;
}

static int read_via_objdump(const char *filename, u64 addr, void *buf,
			    size_t len)
{
	char cmd[PATH_MAX * 2];
	const char *fmt;
	FILE *f;
	int ret;

	fmt = "%s -d --start-address=0x%"PRIx64" --stop-address=0x%"PRIx64" %s";
	ret = snprintf(cmd, sizeof(cmd), fmt, "objdump", addr, addr + len,
		       filename);
	if (ret <= 0 || (size_t)ret >= sizeof(cmd))
		return -1;

	pr_debug("Objdump command is: %s\n", cmd);

	/* Ignore objdump errors */
	strcat(cmd, " 2>/dev/null");

	f = popen(cmd, "r");
	if (!f) {
		pr_debug("popen failed\n");
		return -1;
	}

	ret = read_objdump_output(f, &buf, &len);
	if (len) {
		pr_debug("objdump read too few bytes\n");
		if (!ret)
			ret = len;
	}

	pclose(f);

	return ret;
}

static int read_object_code(u64 addr, size_t len, u8 cpumode,
			    struct thread *thread, struct machine *machine,
			    struct state *state)
{
	struct addr_location al;
	unsigned char buf1[BUFSZ];
	unsigned char buf2[BUFSZ];
	size_t ret_len;
	u64 objdump_addr;
	int ret;

	pr_debug("Reading object code for memory address: %#"PRIx64"\n", addr);

	thread__find_addr_map(thread, machine, cpumode, MAP__FUNCTION, addr,
			      &al);
	if (!al.map || !al.map->dso) {
		pr_debug("thread__find_addr_map failed\n");
		return -1;
	}

	pr_debug("File is: %s\n", al.map->dso->long_name);

	if (al.map->dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS &&
	    !dso__is_kcore(al.map->dso)) {
		pr_debug("Unexpected kernel address - skipping\n");
		return 0;
	}

	pr_debug("On file address is: %#"PRIx64"\n", al.addr);

	if (len > BUFSZ)
		len = BUFSZ;

	/* Do not go off the map */
	if (addr + len > al.map->end)
		len = al.map->end - addr;

	/* Read the object code using perf */
	ret_len = dso__data_read_offset(al.map->dso, machine, al.addr, buf1,
					len);
	if (ret_len != len) {
		pr_debug("dso__data_read_offset failed\n");
		return -1;
	}

	/*
	 * Converting addresses for use by objdump requires more information.
	 * map__load() does that.  See map__rip_2objdump() for details.
	 */
	if (map__load(al.map, NULL))
		return -1;

	/* objdump struggles with kcore - try each map only once */
	if (dso__is_kcore(al.map->dso)) {
		size_t d;

		for (d = 0; d < state->done_cnt; d++) {
			if (state->done[d] == al.map->start) {
				pr_debug("kcore map tested already");
				pr_debug(" - skipping\n");
				return 0;
			}
		}
		if (state->done_cnt >= ARRAY_SIZE(state->done)) {
			pr_debug("Too many kcore maps - skipping\n");
			return 0;
		}
		state->done[state->done_cnt++] = al.map->start;
	}

	/* Read the object code using objdump */
	objdump_addr = map__rip_2objdump(al.map, al.addr);
	ret = read_via_objdump(al.map->dso->long_name, objdump_addr, buf2, len);
	if (ret > 0) {
		/*
		 * The kernel maps are inaccurate - assume objdump is right in
		 * that case.
		 */
		if (cpumode == PERF_RECORD_MISC_KERNEL ||
		    cpumode == PERF_RECORD_MISC_GUEST_KERNEL) {
			len -= ret;
			if (len) {
				pr_debug("Reducing len to %zu\n", len);
			} else if (dso__is_kcore(al.map->dso)) {
				/*
				 * objdump cannot handle very large segments
				 * that may be found in kcore.
				 */
				pr_debug("objdump failed for kcore");
				pr_debug(" - skipping\n");
				return 0;
			} else {
				return -1;
			}
		}
	}
	if (ret < 0) {
		pr_debug("read_via_objdump failed\n");
		return -1;
	}

	/* The results should be identical */
	if (memcmp(buf1, buf2, len)) {
		pr_debug("Bytes read differ from those read by objdump\n");
		return -1;
	}
	pr_debug("Bytes read match those read by objdump\n");

	return 0;
}

static int process_sample_event(struct machine *machine,
				struct perf_evlist *evlist,
				union perf_event *event, struct state *state)
{
	struct perf_sample sample;
	struct thread *thread;
	u8 cpumode;

	if (perf_evlist__parse_sample(evlist, event, &sample)) {
		pr_debug("perf_evlist__parse_sample failed\n");
		return -1;
	}

	thread = machine__findnew_thread(machine, sample.pid);
	if (!thread) {
		pr_debug("machine__findnew_thread failed\n");
		return -1;
	}

	cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;

	return read_object_code(sample.ip, READLEN, cpumode, thread, machine,
				state);
}

static int process_event(struct machine *machine, struct perf_evlist *evlist,
			 union perf_event *event, struct state *state)
{
	if (event->header.type == PERF_RECORD_SAMPLE)
		return process_sample_event(machine, evlist, event, state);

	if (event->header.type < PERF_RECORD_MAX)
		return machine__process_event(machine, event);

	return 0;
}

static int process_events(struct machine *machine, struct perf_evlist *evlist,
			  struct state *state)
{
	union perf_event *event;
	int i, ret;

	for (i = 0; i < evlist->nr_mmaps; i++) {
		while ((event = perf_evlist__mmap_read(evlist, i)) != NULL) {
			ret = process_event(machine, evlist, event, state);
			if (ret < 0)
				return ret;
		}
	}
	return 0;
}

static int comp(const void *a, const void *b)
{
	return *(int *)a - *(int *)b;
}

static void do_sort_something(void)
{
	int buf[40960], i;

	for (i = 0; i < (int)ARRAY_SIZE(buf); i++)
		buf[i] = ARRAY_SIZE(buf) - i - 1;

	qsort(buf, ARRAY_SIZE(buf), sizeof(int), comp);

	for (i = 0; i < (int)ARRAY_SIZE(buf); i++) {
		if (buf[i] != i) {
			pr_debug("qsort failed\n");
			break;
		}
	}
}

static void sort_something(void)
{
	int i;

	for (i = 0; i < 10; i++)
		do_sort_something();
}

static void syscall_something(void)
{
	int pipefd[2];
	int i;

	for (i = 0; i < 1000; i++) {
		if (pipe(pipefd) < 0) {
			pr_debug("pipe failed\n");
			break;
		}
		close(pipefd[1]);
		close(pipefd[0]);
	}
}

static void fs_something(void)
{
	const char *test_file_name = "temp-perf-code-reading-test-file--";
	FILE *f;
	int i;

	for (i = 0; i < 1000; i++) {
		f = fopen(test_file_name, "w+");
		if (f) {
			fclose(f);
			unlink(test_file_name);
		}
	}
}

static void do_something(void)
{
	fs_something();

	sort_something();

	syscall_something();
}

enum {
	TEST_CODE_READING_OK,
	TEST_CODE_READING_NO_VMLINUX,
	TEST_CODE_READING_NO_KCORE,
	TEST_CODE_READING_NO_ACCESS,
	TEST_CODE_READING_NO_KERNEL_OBJ,
};

static int do_test_code_reading(bool try_kcore)
{
	struct machines machines;
	struct machine *machine;
	struct thread *thread;
	struct perf_record_opts opts = {
		.mmap_pages	     = UINT_MAX,
		.user_freq	     = UINT_MAX,
		.user_interval	     = ULLONG_MAX,
		.freq		     = 4000,
		.target		     = {
			.uses_mmap   = true,
		},
	};
	struct state state = {
		.done_cnt = 0,
	};
	struct thread_map *threads = NULL;
	struct cpu_map *cpus = NULL;
	struct perf_evlist *evlist = NULL;
	struct perf_evsel *evsel = NULL;
	int err = -1, ret;
	pid_t pid;
	struct map *map;
	bool have_vmlinux, have_kcore, excl_kernel = false;

	pid = getpid();

	machines__init(&machines);
	machine = &machines.host;

	ret = machine__create_kernel_maps(machine);
	if (ret < 0) {
		pr_debug("machine__create_kernel_maps failed\n");
		goto out_err;
	}

	/* Force the use of kallsyms instead of vmlinux to try kcore */
	if (try_kcore)
		symbol_conf.kallsyms_name = "/proc/kallsyms";

	/* Load kernel map */
	map = machine->vmlinux_maps[MAP__FUNCTION];
	ret = map__load(map, NULL);
	if (ret < 0) {
		pr_debug("map__load failed\n");
		goto out_err;
	}
	have_vmlinux = dso__is_vmlinux(map->dso);
	have_kcore = dso__is_kcore(map->dso);

	/* 2nd time through we just try kcore */
	if (try_kcore && !have_kcore)
		return TEST_CODE_READING_NO_KCORE;

	/* No point getting kernel events if there is no kernel object */
	if (!have_vmlinux && !have_kcore)
		excl_kernel = true;

	threads = thread_map__new_by_tid(pid);
	if (!threads) {
		pr_debug("thread_map__new_by_tid failed\n");
		goto out_err;
	}

	ret = perf_event__synthesize_thread_map(NULL, threads,
						perf_event__process, machine);
	if (ret < 0) {
		pr_debug("perf_event__synthesize_thread_map failed\n");
		goto out_err;
	}

	thread = machine__findnew_thread(machine, pid);
	if (!thread) {
		pr_debug("machine__findnew_thread failed\n");
		goto out_err;
	}

	cpus = cpu_map__new(NULL);
	if (!cpus) {
		pr_debug("cpu_map__new failed\n");
		goto out_err;
	}

	while (1) {
		const char *str;

		evlist = perf_evlist__new();
		if (!evlist) {
			pr_debug("perf_evlist__new failed\n");
			goto out_err;
		}

		perf_evlist__set_maps(evlist, cpus, threads);

		if (excl_kernel)
			str = "cycles:u";
		else
			str = "cycles";
		pr_debug("Parsing event '%s'\n", str);
		ret = parse_events(evlist, str);
		if (ret < 0) {
			pr_debug("parse_events failed\n");
			goto out_err;
		}

		perf_evlist__config(evlist, &opts);

		evsel = perf_evlist__first(evlist);

		evsel->attr.comm = 1;
		evsel->attr.disabled = 1;
		evsel->attr.enable_on_exec = 0;

		ret = perf_evlist__open(evlist);
		if (ret < 0) {
			if (!excl_kernel) {
				excl_kernel = true;
				perf_evlist__delete(evlist);
				evlist = NULL;
				continue;
			}
			pr_debug("perf_evlist__open failed\n");
			goto out_err;
		}
		break;
	}

	ret = perf_evlist__mmap(evlist, UINT_MAX, false);
	if (ret < 0) {
		pr_debug("perf_evlist__mmap failed\n");
		goto out_err;
	}

	perf_evlist__enable(evlist);

	do_something();

	perf_evlist__disable(evlist);

	ret = process_events(machine, evlist, &state);
	if (ret < 0)
		goto out_err;

	if (!have_vmlinux && !have_kcore && !try_kcore)
		err = TEST_CODE_READING_NO_KERNEL_OBJ;
	else if (!have_vmlinux && !try_kcore)
		err = TEST_CODE_READING_NO_VMLINUX;
	else if (excl_kernel)
		err = TEST_CODE_READING_NO_ACCESS;
	else
		err = TEST_CODE_READING_OK;
out_err:
	if (evlist) {
		perf_evlist__munmap(evlist);
		perf_evlist__close(evlist);
		perf_evlist__delete(evlist);
	}
	if (cpus)
		cpu_map__delete(cpus);
	if (threads)
		thread_map__delete(threads);
	machines__destroy_kernel_maps(&machines);
	machine__delete_threads(machine);
	machines__exit(&machines);

	return err;
}

int test__code_reading(void)
{
	int ret;

	ret = do_test_code_reading(false);
	if (!ret)
		ret = do_test_code_reading(true);

	switch (ret) {
	case TEST_CODE_READING_OK:
		return 0;
	case TEST_CODE_READING_NO_VMLINUX:
		fprintf(stderr, " (no vmlinux)");
		return 0;
	case TEST_CODE_READING_NO_KCORE:
		fprintf(stderr, " (no kcore)");
		return 0;
	case TEST_CODE_READING_NO_ACCESS:
		fprintf(stderr, " (no access)");
		return 0;
	case TEST_CODE_READING_NO_KERNEL_OBJ:
		fprintf(stderr, " (no kernel obj)");
		return 0;
	default:
		return -1;
	};
}
Commit	Line	Data
b55ae0a9 AH	1	#include <sys/types.h>
	2	#include <stdlib.h>
	3	#include <unistd.h>
	4	#include <stdio.h>
	5	#include <inttypes.h>
	6	#include <ctype.h>
	7	#include <string.h>
	8
	9	#include "parse-events.h"
	10	#include "evlist.h"
	11	#include "evsel.h"
	12	#include "thread_map.h"
	13	#include "cpumap.h"
	14	#include "machine.h"
	15	#include "event.h"
	16	#include "thread.h"
	17
	18	#include "tests.h"
	19
	20	#define BUFSZ 1024
	21	#define READLEN 128
	22
7a77bc2c AH	23	struct state {
	24	u64 done[1024];
	25	size_t done_cnt;
	26	};
	27
b55ae0a9 AH	28	static unsigned int hex(char c)
	29	{
	30	if (c >= '0' && c <= '9')
	31	return c - '0';
	32	if (c >= 'a' && c <= 'f')
	33	return c - 'a' + 10;
	34	return c - 'A' + 10;
	35	}
	36
	37	static void read_objdump_line(const char line, size_t line_len, void *buf,
	38	size_t *len)
	39	{
	40	const char *p;
	41	size_t i;
	42
	43	/* Skip to a colon */
	44	p = strchr(line, ':');
	45	if (!p)
	46	return;
	47	i = p + 1 - line;
	48
	49	/* Read bytes */
	50	while (*len) {
	51	char c1, c2;
	52
	53	/* Skip spaces */
	54	for (; i < line_len; i++) {
	55	if (!isspace(line[i]))
	56	break;
	57	}
	58	/* Get 2 hex digits */
	59	if (i >= line_len \|\| !isxdigit(line[i]))
	60	break;
	61	c1 = line[i++];
	62	if (i >= line_len \|\| !isxdigit(line[i]))
	63	break;
	64	c2 = line[i++];
	65	/* Followed by a space */
	66	if (i < line_len && line[i] && !isspace(line[i]))
	67	break;
	68	/* Store byte */
	69	(unsigned char )*buf = (hex(c1) << 4) \| hex(c2);
	70	*buf += 1;
	71	*len -= 1;
	72	}
	73	}
	74
	75	static int read_objdump_output(FILE f, void buf, size_t len)
	76	{
	77	char *line = NULL;
	78	size_t line_len;
	79	ssize_t ret;
	80	int err = 0;
	81
	82	while (1) {
	83	ret = getline(&line, &line_len, f);
	84	if (feof(f))
	85	break;
	86	if (ret < 0) {
	87	pr_debug("getline failed\n");
	88	err = -1;
	89	break;
	90	}
	91	read_objdump_line(line, ret, buf, len);
92	}
93
94	free(line);
95
96	return err;
97	}
98
99	static int read_via_objdump(const char filename, u64 addr, void buf,
100	size_t len)
101	{
102	char cmd[PATH_MAX * 2];
103	const char *fmt;
104	FILE *f;
105	int ret;
106
107	fmt = "%s -d --start-address=0x%"PRIx64" --stop-address=0x%"PRIx64" %s";
108	ret = snprintf(cmd, sizeof(cmd), fmt, "objdump", addr, addr + len,
109	filename);
110	if (ret <= 0 \|\| (size_t)ret >= sizeof(cmd))
111	return -1;
112
113	pr_debug("Objdump command is: %s\n", cmd);
114
7a77bc2c AH	115	/* Ignore objdump errors */
	116	strcat(cmd, " 2>/dev/null");
	117
b55ae0a9 AH	118	f = popen(cmd, "r");
	119	if (!f) {
	120	pr_debug("popen failed\n");
	121	return -1;
	122	}
	123
	124	ret = read_objdump_output(f, &buf, &len);
	125	if (len) {
	126	pr_debug("objdump read too few bytes\n");
	127	if (!ret)
	128	ret = len;
	129	}
	130
	131	pclose(f);
	132
	133	return ret;
	134	}
	135
	136	static int read_object_code(u64 addr, size_t len, u8 cpumode,
7a77bc2c AH	137	struct thread thread, struct machine machine,
7a77bc2c AH	138	struct state *state)
b55ae0a9 AH	139	{
	140	struct addr_location al;
	141	unsigned char buf1[BUFSZ];
	142	unsigned char buf2[BUFSZ];
	143	size_t ret_len;
	144	u64 objdump_addr;
	145	int ret;
	146
	147	pr_debug("Reading object code for memory address: %#"PRIx64"\n", addr);
	148
	149	thread__find_addr_map(thread, machine, cpumode, MAP__FUNCTION, addr,
326f59bf	150	&al);
b55ae0a9 AH	151	if (!al.map \|\| !al.map->dso) {
	152	pr_debug("thread__find_addr_map failed\n");
	153	return -1;
	154	}
	155
	156	pr_debug("File is: %s\n", al.map->dso->long_name);
	157
7a77bc2c AH	158	if (al.map->dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS &&
7a77bc2c AH	159	!dso__is_kcore(al.map->dso)) {
b55ae0a9 AH	160	pr_debug("Unexpected kernel address - skipping\n");
	161	return 0;
	162	}
	163
	164	pr_debug("On file address is: %#"PRIx64"\n", al.addr);
	165
	166	if (len > BUFSZ)
	167	len = BUFSZ;
	168
	169	/* Do not go off the map */
	170	if (addr + len > al.map->end)
	171	len = al.map->end - addr;
	172
	173	/* Read the object code using perf */
	174	ret_len = dso__data_read_offset(al.map->dso, machine, al.addr, buf1,
	175	len);
	176	if (ret_len != len) {
	177	pr_debug("dso__data_read_offset failed\n");
	178	return -1;
	179	}
	180
	181	/*
	182	* Converting addresses for use by objdump requires more information.
	183	* map__load() does that. See map__rip_2objdump() for details.
	184	*/
	185	if (map__load(al.map, NULL))
	186	return -1;
	187
7a77bc2c AH	188	/* objdump struggles with kcore - try each map only once */
	189	if (dso__is_kcore(al.map->dso)) {
	190	size_t d;
	191
	192	for (d = 0; d < state->done_cnt; d++) {
	193	if (state->done[d] == al.map->start) {
	194	pr_debug("kcore map tested already");
	195	pr_debug(" - skipping\n");
	196	return 0;
	197	}
	198	}
	199	if (state->done_cnt >= ARRAY_SIZE(state->done)) {
	200	pr_debug("Too many kcore maps - skipping\n");
	201	return 0;
	202	}
	203	state->done[state->done_cnt++] = al.map->start;
	204	}
	205
b55ae0a9 AH	206	/* Read the object code using objdump */
	207	objdump_addr = map__rip_2objdump(al.map, al.addr);
	208	ret = read_via_objdump(al.map->dso->long_name, objdump_addr, buf2, len);
	209	if (ret > 0) {
	210	/*
	211	* The kernel maps are inaccurate - assume objdump is right in
	212	* that case.
	213	*/
	214	if (cpumode == PERF_RECORD_MISC_KERNEL \|\|
	215	cpumode == PERF_RECORD_MISC_GUEST_KERNEL) {
	216	len -= ret;
7a77bc2c	217	if (len) {
b55ae0a9	218	pr_debug("Reducing len to %zu\n", len);
7a77bc2c AH	219	} else if (dso__is_kcore(al.map->dso)) {
	220	/*
	221	* objdump cannot handle very large segments
	222	* that may be found in kcore.
	223	*/
	224	pr_debug("objdump failed for kcore");
	225	pr_debug(" - skipping\n");
	226	return 0;
	227	} else {
b55ae0a9	228	return -1;
7a77bc2c	229	}
b55ae0a9 AH	230	}
	231	}
	232	if (ret < 0) {
	233	pr_debug("read_via_objdump failed\n");
	234	return -1;
	235	}
	236
	237	/* The results should be identical */
	238	if (memcmp(buf1, buf2, len)) {
	239	pr_debug("Bytes read differ from those read by objdump\n");
	240	return -1;
	241	}
	242	pr_debug("Bytes read match those read by objdump\n");
	243
	244	return 0;
	245	}
	246
	247	static int process_sample_event(struct machine *machine,
	248	struct perf_evlist *evlist,
7a77bc2c	249	union perf_event event, struct state state)
b55ae0a9 AH	250	{
	251	struct perf_sample sample;
	252	struct thread *thread;
	253	u8 cpumode;
	254
	255	if (perf_evlist__parse_sample(evlist, event, &sample)) {
	256	pr_debug("perf_evlist__parse_sample failed\n");
	257	return -1;
	258	}
	259
	260	thread = machine__findnew_thread(machine, sample.pid);
	261	if (!thread) {
	262	pr_debug("machine__findnew_thread failed\n");
	263	return -1;
	264	}
	265
	266	cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
	267
7a77bc2c AH	268	return read_object_code(sample.ip, READLEN, cpumode, thread, machine,
7a77bc2c AH	269	state);
b55ae0a9 AH	270	}
	271
	272	static int process_event(struct machine machine, struct perf_evlist evlist,
7a77bc2c	273	union perf_event event, struct state state)
b55ae0a9 AH	274	{
b55ae0a9 AH	275	if (event->header.type == PERF_RECORD_SAMPLE)
7a77bc2c	276	return process_sample_event(machine, evlist, event, state);
b55ae0a9 AH	277
	278	if (event->header.type < PERF_RECORD_MAX)
	279	return machine__process_event(machine, event);
	280
	281	return 0;
	282	}
	283
7a77bc2c AH	284	static int process_events(struct machine machine, struct perf_evlist evlist,
7a77bc2c AH	285	struct state *state)
b55ae0a9 AH	286	{
	287	union perf_event *event;
	288	int i, ret;
	289
	290	for (i = 0; i < evlist->nr_mmaps; i++) {
	291	while ((event = perf_evlist__mmap_read(evlist, i)) != NULL) {
7a77bc2c	292	ret = process_event(machine, evlist, event, state);
b55ae0a9 AH	293	if (ret < 0)
	294	return ret;
	295	}
	296	}
	297	return 0;
	298	}
	299
	300	static int comp(const void a, const void b)
	301	{
	302	return (int )a - (int )b;
	303	}
	304
	305	static void do_sort_something(void)
	306	{
309b5185	307	int buf[40960], i;
b55ae0a9	308
309b5185 DA	309	for (i = 0; i < (int)ARRAY_SIZE(buf); i++)
309b5185 DA	310	buf[i] = ARRAY_SIZE(buf) - i - 1;
b55ae0a9	311
309b5185	312	qsort(buf, ARRAY_SIZE(buf), sizeof(int), comp);
b55ae0a9	313
309b5185	314	for (i = 0; i < (int)ARRAY_SIZE(buf); i++) {
b55ae0a9 AH	315	if (buf[i] != i) {
	316	pr_debug("qsort failed\n");
	317	break;
	318	}
	319	}
	320	}
	321
	322	static void sort_something(void)
	323	{
	324	int i;
	325
	326	for (i = 0; i < 10; i++)
	327	do_sort_something();
	328	}
	329
	330	static void syscall_something(void)
	331	{
	332	int pipefd[2];
	333	int i;
	334
	335	for (i = 0; i < 1000; i++) {
	336	if (pipe(pipefd) < 0) {
	337	pr_debug("pipe failed\n");
	338	break;
	339	}
	340	close(pipefd[1]);
	341	close(pipefd[0]);
	342	}
	343	}
	344
	345	static void fs_something(void)
	346	{
	347	const char *test_file_name = "temp-perf-code-reading-test-file--";
	348	FILE *f;
	349	int i;
	350
	351	for (i = 0; i < 1000; i++) {
	352	f = fopen(test_file_name, "w+");
	353	if (f) {
	354	fclose(f);
	355	unlink(test_file_name);
	356	}
	357	}
	358	}
	359
	360	static void do_something(void)
	361	{
	362	fs_something();
	363
	364	sort_something();
	365
	366	syscall_something();
	367	}
	368
	369	enum {
	370	TEST_CODE_READING_OK,
	371	TEST_CODE_READING_NO_VMLINUX,
7a77bc2c	372	TEST_CODE_READING_NO_KCORE,
b55ae0a9	373	TEST_CODE_READING_NO_ACCESS,
7a77bc2c	374	TEST_CODE_READING_NO_KERNEL_OBJ,
b55ae0a9 AH	375	};
b55ae0a9 AH	376
7a77bc2c	377	static int do_test_code_reading(bool try_kcore)
b55ae0a9 AH	378	{
	379	struct machines machines;
	380	struct machine *machine;
	381	struct thread *thread;
	382	struct perf_record_opts opts = {
	383	.mmap_pages = UINT_MAX,
	384	.user_freq = UINT_MAX,
	385	.user_interval = ULLONG_MAX,
	386	.freq = 4000,
	387	.target = {
	388	.uses_mmap = true,
	389	},
	390	};
7a77bc2c AH	391	struct state state = {
	392	.done_cnt = 0,
	393	};
b55ae0a9 AH	394	struct thread_map *threads = NULL;
	395	struct cpu_map *cpus = NULL;
	396	struct perf_evlist *evlist = NULL;
	397	struct perf_evsel *evsel = NULL;
	398	int err = -1, ret;
	399	pid_t pid;
	400	struct map *map;
7a77bc2c	401	bool have_vmlinux, have_kcore, excl_kernel = false;
b55ae0a9 AH	402
	403	pid = getpid();
	404
	405	machines__init(&machines);
	406	machine = &machines.host;
	407
	408	ret = machine__create_kernel_maps(machine);
	409	if (ret < 0) {
	410	pr_debug("machine__create_kernel_maps failed\n");
	411	goto out_err;
	412	}
	413
7a77bc2c AH	414	/* Force the use of kallsyms instead of vmlinux to try kcore */
	415	if (try_kcore)
	416	symbol_conf.kallsyms_name = "/proc/kallsyms";
	417
b55ae0a9 AH	418	/* Load kernel map */
	419	map = machine->vmlinux_maps[MAP__FUNCTION];
	420	ret = map__load(map, NULL);
	421	if (ret < 0) {
	422	pr_debug("map__load failed\n");
	423	goto out_err;
	424	}
7a77bc2c AH	425	have_vmlinux = dso__is_vmlinux(map->dso);
	426	have_kcore = dso__is_kcore(map->dso);
	427
	428	/* 2nd time through we just try kcore */
	429	if (try_kcore && !have_kcore)
	430	return TEST_CODE_READING_NO_KCORE;
	431
	432	/* No point getting kernel events if there is no kernel object */
	433	if (!have_vmlinux && !have_kcore)
b55ae0a9 AH	434	excl_kernel = true;
	435
	436	threads = thread_map__new_by_tid(pid);
	437	if (!threads) {
	438	pr_debug("thread_map__new_by_tid failed\n");
	439	goto out_err;
	440	}
	441
	442	ret = perf_event__synthesize_thread_map(NULL, threads,
	443	perf_event__process, machine);
	444	if (ret < 0) {
	445	pr_debug("perf_event__synthesize_thread_map failed\n");
	446	goto out_err;
	447	}
	448
	449	thread = machine__findnew_thread(machine, pid);
	450	if (!thread) {
	451	pr_debug("machine__findnew_thread failed\n");
	452	goto out_err;
	453	}
	454
	455	cpus = cpu_map__new(NULL);
	456	if (!cpus) {
	457	pr_debug("cpu_map__new failed\n");
	458	goto out_err;
	459	}
	460
	461	while (1) {
	462	const char *str;
	463
	464	evlist = perf_evlist__new();
	465	if (!evlist) {
	466	pr_debug("perf_evlist__new failed\n");
	467	goto out_err;
	468	}
	469
	470	perf_evlist__set_maps(evlist, cpus, threads);
	471
	472	if (excl_kernel)
	473	str = "cycles:u";
	474	else
	475	str = "cycles";
	476	pr_debug("Parsing event '%s'\n", str);
	477	ret = parse_events(evlist, str);
	478	if (ret < 0) {
	479	pr_debug("parse_events failed\n");
	480	goto out_err;
	481	}
	482
	483	perf_evlist__config(evlist, &opts);
	484
	485	evsel = perf_evlist__first(evlist);
	486
	487	evsel->attr.comm = 1;
	488	evsel->attr.disabled = 1;
	489	evsel->attr.enable_on_exec = 0;
	490
	491	ret = perf_evlist__open(evlist);
	492	if (ret < 0) {
	493	if (!excl_kernel) {
	494	excl_kernel = true;
	495	perf_evlist__delete(evlist);
	496	evlist = NULL;
	497	continue;
498	}
499	pr_debug("perf_evlist__open failed\n");
500	goto out_err;
501	}
502	break;
503	}
504
505	ret = perf_evlist__mmap(evlist, UINT_MAX, false);
506	if (ret < 0) {
507	pr_debug("perf_evlist__mmap failed\n");
508	goto out_err;
509	}
510
511	perf_evlist__enable(evlist);
512
513	do_something();
514
515	perf_evlist__disable(evlist);
516
7a77bc2c	517	ret = process_events(machine, evlist, &state);
b55ae0a9 AH	518	if (ret < 0)
	519	goto out_err;
	520
7a77bc2c AH	521	if (!have_vmlinux && !have_kcore && !try_kcore)
	522	err = TEST_CODE_READING_NO_KERNEL_OBJ;
	523	else if (!have_vmlinux && !try_kcore)
b55ae0a9 AH	524	err = TEST_CODE_READING_NO_VMLINUX;
	525	else if (excl_kernel)
	526	err = TEST_CODE_READING_NO_ACCESS;
	527	else
	528	err = TEST_CODE_READING_OK;
	529	out_err:
	530	if (evlist) {
	531	perf_evlist__munmap(evlist);
	532	perf_evlist__close(evlist);
	533	perf_evlist__delete(evlist);
	534	}
	535	if (cpus)
	536	cpu_map__delete(cpus);
	537	if (threads)
	538	thread_map__delete(threads);
	539	machines__destroy_kernel_maps(&machines);
	540	machine__delete_threads(machine);
	541	machines__exit(&machines);
	542
	543	return err;
	544	}
	545
	546	int test__code_reading(void)
	547	{
	548	int ret;
	549
7a77bc2c AH	550	ret = do_test_code_reading(false);
	551	if (!ret)
	552	ret = do_test_code_reading(true);
b55ae0a9 AH	553
	554	switch (ret) {
	555	case TEST_CODE_READING_OK:
	556	return 0;
	557	case TEST_CODE_READING_NO_VMLINUX:
	558	fprintf(stderr, " (no vmlinux)");
	559	return 0;
7a77bc2c AH	560	case TEST_CODE_READING_NO_KCORE:
	561	fprintf(stderr, " (no kcore)");
	562	return 0;
b55ae0a9 AH	563	case TEST_CODE_READING_NO_ACCESS:
	564	fprintf(stderr, " (no access)");
	565	return 0;
7a77bc2c AH	566	case TEST_CODE_READING_NO_KERNEL_OBJ:
	567	fprintf(stderr, " (no kernel obj)");
	568	return 0;
b55ae0a9 AH	569	default:
	570	return -1;
	571	};
	572	}