/*
* builtin-top.c
*
* Builtin top command: Display a continuously updated profile of
* any workload, CPU or specific PID.
*
* Copyright (C) 2008, Red Hat Inc, Ingo Molnar <mingo@redhat.com>
*
* Improvements and fixes by:
*
* Arjan van de Ven <arjan@linux.intel.com>
* Yanmin Zhang <yanmin.zhang@intel.com>
* Wu Fengguang <fengguang.wu@intel.com>
* Mike Galbraith <efault@gmx.de>
* Paul Mackerras <paulus@samba.org>
*
* Released under the GPL v2. (and only v2, not any later version)
*/
#include "builtin.h"
#include "perf.h"
#include "util/symbol.h"
#include "util/color.h"
#include "util/util.h"
#include "util/rbtree.h"
#include "util/parse-options.h"
#include "util/parse-events.h"
#include <assert.h>
#include <fcntl.h>
#include <stdio.h>
#include <errno.h>
#include <time.h>
#include <sched.h>
#include <pthread.h>
#include <sys/syscall.h>
#include <sys/ioctl.h>
#include <sys/poll.h>
#include <sys/prctl.h>
#include <sys/wait.h>
#include <sys/uio.h>
#include <sys/mman.h>
#include <linux/unistd.h>
#include <linux/types.h>
static int fd[MAX_NR_CPUS][MAX_COUNTERS];
static int system_wide = 0;
static int default_interval = 100000;
static __u64 count_filter = 5;
static int print_entries = 15;
static int target_pid = -1;
static int profile_cpu = -1;
static int nr_cpus = 0;
static unsigned int realtime_prio = 0;
static int group = 0;
static unsigned int page_size;
static unsigned int mmap_pages = 16;
static int freq = 0;
static char *sym_filter;
static unsigned long filter_start;
static unsigned long filter_end;
static int delay_secs = 2;
static int zero;
static int dump_symtab;
/*
* Symbols
*/
static uint64_t min_ip;
static uint64_t max_ip = -1ll;
struct sym_entry {
struct rb_node rb_node;
struct list_head node;
unsigned long count[MAX_COUNTERS];
unsigned long snap_count;
double weight;
int skip;
};
struct sym_entry *sym_filter_entry;
struct dso *kernel_dso;
/*
* Symbols will be added here in record_ip and will get out
* after decayed.
*/
static LIST_HEAD(active_symbols);
static pthread_mutex_t active_symbols_lock = PTHREAD_MUTEX_INITIALIZER;
/*
* Ordering weight: count-1 * count-2 * ... / count-n
*/
static double sym_weight(const struct sym_entry *sym)
{
double weight = sym->snap_count;
int counter;
for (counter = 1; counter < nr_counters-1; counter++)
weight *= sym->count[counter];
weight /= (sym->count[counter] + 1);
return weight;
}
static long samples;
static long userspace_samples;
static const char CONSOLE_CLEAR[] = "[H[2J";
static void __list_insert_active_sym(struct sym_entry *syme)
{
list_add(&syme->node, &active_symbols);
}
static void list_remove_active_sym(struct sym_entry *syme)
{
pthread_mutex_lock(&active_symbols_lock);
list_del_init(&syme->node);
pthread_mutex_unlock(&active_symbols_lock);
}
static void rb_insert_active_sym(struct rb_root *tree, struct sym_entry *se)
{
struct rb_node **p = &tree->rb_node;
struct rb_node *parent = NULL;
struct sym_entry *iter;
while (*p != NULL) {
parent = *p;
iter = rb_entry(parent, struct sym_entry, rb_node);
if (se->weight > iter->weight)
p = &(*p)->rb_left;
else
p = &(*p)->rb_right;
}
rb_link_node(&se->rb_node, parent, p);
rb_insert_color(&se->rb_node, tree);
}
static void print_sym_table(void)
{
int printed = 0, j;
int counter;
float samples_per_sec = samples/delay_secs;
float ksamples_per_sec = (samples-userspace_samples)/delay_secs;
float sum_ksamples = 0.0;
struct sym_entry *syme, *n;
struct rb_root tmp = RB_ROOT;
struct rb_node *nd;
samples = userspace_samples = 0;
/* Sort the active symbols */
pthread_mutex_lock(&active_symbols_lock);
syme = list_entry(active_symbols.next, struct sym_entry, node);
pthread_mutex_unlock(&active_symbols_lock);
list_for_each_entry_safe_from(syme, n, &active_symbols, node) {
syme->snap_count = syme->count[0];
if (syme->snap_count != 0) {
syme->weight = sym_weight(syme);
rb_insert_active_sym(&tmp, syme);
sum_ksamples += syme->snap_count;
for (j = 0; j < nr_counters; j++)
syme->count[j] = zero ? 0 : syme->count[j] * 7 / 8;
} else
list_remove_active_sym(syme);
}
puts(CONSOLE_CLEAR);
printf(
"------------------------------------------------------------------------------\n");
printf( " PerfTop:%8.0f irqs/sec kernel:%4.1f%% [",
samples_per_sec,
100.0 - (100.0*((samples_per_sec-ksamples_per_sec)/samples_per_sec)));
if (nr_counters == 1) {
printf("%Ld", attrs[0].sample_period);
if (freq)
printf("Hz ");
else
printf(" ");
}
for (counter = 0; counter < nr_counters; counter++) {
if (counter)
printf("/");
printf("%s", event_name(counter));
}
printf( "], ");
if (target_pid != -1)
printf(" (target_pid: %d", target_pid);
else
printf(" (all");
if (profile_cpu != -1)
printf(", cpu: %d)\n", profile_cpu);
else {
if (target_pid != -1)
printf(")\n");
else
printf(", %d CPUs)\n", nr_cpus);
}
printf("------------------------------------------------------------------------------\n\n");
if (nr_counters == 1)
printf(" samples pcnt");
else
printf(" weight samples pcnt");
printf(" RIP kernel function\n"
" ______ _______ _____ ________________ _______________\n\n"
);
for (nd = rb_first(&tmp); nd; nd = rb_next(nd)) {
struct sym_entry *syme = rb_entry(nd, struct sym_entry, rb_node);
struct symbol *sym = (struct symbol *)(syme + 1);
char *color = PERF_COLOR_NORMAL;
double pcnt;
if (++printed > print_entries || syme->snap_count < count_filter)
continue;
pcnt = 100.0 - (100.0 * ((sum_ksamples - syme->snap_count) /
sum_ksamples));
/*
* We color high-overhead entries in red, low-overhead
* entries in green - and keep the middle ground normal:
*/
if (pcnt >= 5.0)
color = PERF_COLOR_RED;
if (pcnt < 0.5)
color = PERF_COLOR_GREEN;
if (nr_counters == 1)
printf("%20.2f - ", syme->weight);
else
printf("%9.1f %10ld - ", syme->weight, syme->snap_count);
color_fprintf(stdout, color, "%4.1f%%", pcnt);
printf(" - %016llx : %s\n", sym->start, sym->name);
}
}
static void *display_thread(void *arg)
{
struct pollfd stdin_poll = { .fd = 0, .events = POLLIN };
int delay_msecs = delay_secs * 1000;
printf("PerfTop refresh period: %d seconds\n", delay_secs);
do {
print_sym_table();
} while (!poll(&stdin_poll, 1, delay_msecs) == 1);
printf("key pressed - exiting.\n");
exit(0);
return NULL;
}
static int symbol_filter(struct dso *self, struct symbol *sym)
{
static int filter_match;
struct sym_entry *syme;
const char *name = sym->name;
if (!strcmp(name, "_text") ||
!strcmp(name, "_etext") ||
!strcmp(name, "_sinittext") ||
!strncmp("init_module", name, 11) ||
!strncmp("cleanup_module", name, 14) ||
strstr(name, "_text_start") ||
strstr(name, "_text_end"))
return 1;
syme = dso__sym_priv(self, sym);
/* Tag samples to be skipped. */
if (!strcmp("default_idle", name) ||
!strcmp("cpu_idle", name) ||
!strcmp("enter_idle", name) ||
!strcmp("exit_idle", name) ||
!strcmp("mwait_idle", name))
syme->skip = 1;
if (filter_match == 1) {
filter_end = sym->start;
filter_match = -1;
if (filter_end - filter_start > 10000) {
fprintf(stderr,
"hm, too large filter symbol <%s> - skipping.\n",
sym_filter);
fprintf(stderr, "symbol filter start: %016lx\n",
filter_start);
fprintf(stderr, " end: %016lx\n",
filter_end);
filter_end = filter_start = 0;
sym_filter = NULL;
sleep(1);
}
}
if (filter_match == 0 && sym_filter && !strcmp(name, sym_filter)) {
filter_match = 1;
filter_start = sym->start;
}
return 0;
}
static int parse_symbols(void)
{
struct rb_node *node;
struct symbol *sym;
kernel_dso = dso__new("[kernel]", sizeof(struct sym_entry));
if (kernel_dso == NULL)
return -1;
if (dso__load_kernel(kernel_dso, NULL, symbol_filter, 1) != 0)
goto out_delete_dso;
node = rb_first(&kernel_dso->syms);
sym = rb_entry(node, struct symbol, rb_node);
min_ip = sym->start;
node = rb_last(&kernel_dso->syms);
sym = rb_entry(node, struct symbol, rb_node);
max_ip = sym->end;
if (dump_symtab)
dso__fprintf(kernel_dso, stderr);
return 0;
out_delete_dso:
dso__delete(kernel_dso);
kernel_dso = NULL;
return -1;
}
#define TRACE_COUNT 3
/*
* Binary search in the histogram table and record the hit:
*/
static void record_ip(uint64_t ip, int counter)
{
struct symbol *sym = dso__find_symbol(kernel_dso, ip);
if (sym != NULL) {
struct sym_entry *syme = dso__sym_priv(kernel_dso, sym);
if (!syme->skip) {
syme->count[counter]++;
pthread_mutex_lock(&active_symbols_lock);
if (list_empty(&syme->node) || !syme->node.next)
__list_insert_active_sym(syme);
pthread_mutex_unlock(&active_symbols_lock);
return;
}
}
samples--;
}
static void process_event(uint64_t ip, int counter)
{
samples++;
if (ip < min_ip || ip > max_ip) {
userspace_samples++;
return;
}
record_ip(ip, counter);
}
struct mmap_data {
int counter;
void *base;
unsigned int mask;
unsigned int prev;
};
static unsigned int mmap_read_head(struct mmap_data *md)
{
struct perf_counter_mmap_page *pc = md->base;
int head;
head = pc->data_head;
rmb();
return head;
}
struct timeval last_read, this_read;
static void mmap_read_counter(struct mmap_data *md)
{
unsigned int head = mmap_read_head(md);
unsigned int old = md->prev;
unsigned char *data = md->base + page_size;
int diff;
gettimeofday(&this_read, NULL);
/*
* If we're further behind than half the buffer, there's a chance
* the writer will bite our tail and mess up the samples under us.
*
* If we somehow ended up ahead of the head, we got messed up.
*
* In either case, truncate and restart at head.
*/
diff = head - old;
if (diff > md->mask / 2 || diff < 0) {
struct timeval iv;
unsigned long msecs;
timersub(&this_read, &last_read, &iv);
msecs = iv.tv_sec*1000 + iv.tv_usec/1000;
fprintf(stderr, "WARNING: failed to keep up with mmap data."
" Last read %lu msecs ago.\n", msecs);
/*
* head points to a known good entry, start there.
*/
old = head;
}
last_read = this_read;
for (; old != head;) {
struct ip_event {
struct perf_event_header header;
__u64 ip;
__u32 pid, target_pid;
};
struct mmap_event {
struct perf_event_header header;
__u32 pid, target_pid;
__u64 start;
__u64 len;
__u64 pgoff;
char filename[PATH_MAX];
};
typedef union event_union {
struct perf_event_header header;
struct ip_event ip;
struct mmap_event mmap;
} event_t;
event_t *event = (event_t *)&data[old & md->mask];
event_t event_copy;
size_t size = event->header.size;
/*
* Event straddles the mmap boundary -- header should always
* be inside due to u64 alignment of output.
*/
if ((old & md->mask) + size != ((old + size) & md->mask)) {
unsigned int offset = old;
unsigned int len = min(sizeof(*event), size), cpy;
void *dst = &event_copy;
do {
cpy = min(md->mask + 1 - (offset & md->mask), len);
memcpy(dst, &data[offset & md->mask], cpy);
offset += cpy;
dst += cpy;
len -= cpy;
} while (len);
event = &event_copy;
}
old += size;
if (event->header.misc & PERF_EVENT_MISC_OVERFLOW) {
if (event->header.type & PERF_SAMPLE_IP)
process_event(event->ip.ip, md->counter);
}
}
md->prev = old;
}
static struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS];
static struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS];
static void mmap_read(void)
{
int i, counter;
for (i = 0; i < nr_cpus; i++) {
for (counter = 0; counter < nr_counters; counter++)
mmap_read_counter(&mmap_array[i][counter]);
}
}
static int __cmd_top(void)
{
struct perf_counter_attr *attr;
pthread_t thread;
int i, counter, group_fd, nr_poll = 0;
unsigned int cpu;
int ret;
for (i = 0; i < nr_cpus; i++) {
group_fd = -1;
for (counter = 0; counter < nr_counters; counter++) {
cpu = profile_cpu;
if (target_pid == -1 && profile_cpu == -1)
cpu = i;
attr = attrs + counter;
attr->sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_TID;
attr->freq = freq;
fd[i][counter] = sys_perf_counter_open(attr, target_pid, cpu, group_fd, 0);
if (fd[i][counter] < 0) {
int err = errno;
error("syscall returned with %d (%s)\n",
fd[i][counter], strerror(err));
if (err == EPERM)
printf("Are you root?\n");
exit(-1);
}
assert(fd[i][counter] >= 0);
fcntl(fd[i][counter], F_SETFL, O_NONBLOCK);
/*
* First counter acts as the group leader:
*/
if (group && group_fd == -1)
group_fd = fd[i][counter];
event_array[nr_poll].fd = fd[i][counter];
event_array[nr_poll].events = POLLIN;
nr_poll++;
mmap_array[i][counter].counter = counter;
mmap_array[i][counter].prev = 0;
mmap_array[i][counter].mask = mmap_pages*page_size - 1;
mmap_array[i][counter].base = mmap(NULL, (mmap_pages+1)*page_size,
PROT_READ, MAP_SHARED, fd[i][counter], 0);
if (mmap_array[i][counter].base == MAP_FAILED)
die("failed to mmap with %d (%s)\n", errno, strerror(errno));
}
}
/* Wait for a minimal set of events before starting the snapshot */
poll(event_array, nr_poll, 100);
mmap_read();
if (pthread_create(&thread, NULL, display_thread, NULL)) {
printf("Could not create display thread.\n");
exit(-1);
}
if (realtime_prio) {
struct sched_param param;
param.sched_priority = realtime_prio;
if (sched_setscheduler(0, SCHED_FIFO, ¶m)) {
printf("Could not set realtime priority.\n");
exit(-1);
}
}
while (1) {
int hits = samples;
mmap_read();
if (hits == samples)
ret = poll(event_array, nr_poll, 100);
}
return 0;
}
static const char * const top_usage[] = {
"perf top [<options>]",
NULL
};
static const struct option options[] = {
OPT_CALLBACK('e', "event", NULL, "event",
"event selector. use 'perf list' to list available events",
parse_events),
OPT_INTEGER('c', "count", &default_interval,
"event period to sample"),
OPT_INTEGER('p', "pid", &target_pid,
"profile events on existing pid"),
OPT_BOOLEAN('a', "all-cpus", &system_wide,
"system-wide collection from all CPUs"),
OPT_INTEGER('C', "CPU", &profile_cpu,
"CPU to profile on"),
OPT_INTEGER('m', "mmap-pages", &mmap_pages,
"number of mmap data pages"),
OPT_INTEGER('r', "realtime", &realtime_prio,
"collect data with this RT SCHED_FIFO priority"),
OPT_INTEGER('d', "delay", &delay_secs,
"number of seconds to delay between refreshes"),
OPT_BOOLEAN('D', "dump-symtab", &dump_symtab,
"dump the symbol table used for profiling"),
OPT_INTEGER('f', "count-filter", &count_filter,
"only display functions with more events than this"),
OPT_BOOLEAN('g', "group", &group,
"put the counters into a counter group"),
OPT_STRING('s', "sym-filter", &sym_filter, "pattern",
"only display symbols matchig this pattern"),
OPT_BOOLEAN('z', "zero", &group,
"zero history across updates"),
OPT_INTEGER('F', "freq", &freq,
"profile at this frequency"),
OPT_INTEGER('E', "entries", &print_entries,
"display this many functions"),
OPT_END()
};
int cmd_top(int argc, const char **argv, const char *prefix)
{
int counter;
page_size = sysconf(_SC_PAGE_SIZE);
argc = parse_options(argc, argv, options, top_usage, 0);
if (argc)
usage_with_options(top_usage, options);
if (freq) {
default_interval = freq;
freq = 1;
}
/* CPU and PID are mutually exclusive */
if (target_pid != -1 && profile_cpu != -1) {
printf("WARNING: PID switch overriding CPU\n");
sleep(1);
profile_cpu = -1;
}
if (!nr_counters)
nr_counters = 1;
if (delay_secs < 1)
delay_secs = 1;
parse_symbols();
/*
* Fill in the ones not specifically initialized via -c:
*/
for (counter = 0; counter < nr_counters; counter++) {
if (attrs[counter].sample_period)
continue;
attrs[counter].sample_period = default_interval;
}
nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
assert(nr_cpus <= MAX_NR_CPUS);
assert(nr_cpus >= 0);
if (target_pid != -1 || profile_cpu != -1)
nr_cpus = 1;
return __cmd_top();
}
