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-rw-r--r--Documentation/perf_counter/builtin-top.c744
1 files changed, 744 insertions, 0 deletions
diff --git a/Documentation/perf_counter/builtin-top.c b/Documentation/perf_counter/builtin-top.c
new file mode 100644
index 000000000000..24a887907a7a
--- /dev/null
+++ b/Documentation/perf_counter/builtin-top.c
@@ -0,0 +1,744 @@
+/*
+ * kerneltop.c: show top kernel functions - performance counters showcase
+
+ Build with:
+
+ make -C Documentation/perf_counter/
+
+ Sample output:
+
+------------------------------------------------------------------------------
+ KernelTop: 2669 irqs/sec [cache-misses/cache-refs], (all, cpu: 2)
+------------------------------------------------------------------------------
+
+ weight RIP kernel function
+ ______ ________________ _______________
+
+ 35.20 - ffffffff804ce74b : skb_copy_and_csum_dev
+ 33.00 - ffffffff804cb740 : sock_alloc_send_skb
+ 31.26 - ffffffff804ce808 : skb_push
+ 22.43 - ffffffff80510004 : tcp_established_options
+ 19.00 - ffffffff8027d250 : find_get_page
+ 15.76 - ffffffff804e4fc9 : eth_type_trans
+ 15.20 - ffffffff804d8baa : dst_release
+ 14.86 - ffffffff804cf5d8 : skb_release_head_state
+ 14.00 - ffffffff802217d5 : read_hpet
+ 12.00 - ffffffff804ffb7f : __ip_local_out
+ 11.97 - ffffffff804fc0c8 : ip_local_deliver_finish
+ 8.54 - ffffffff805001a3 : ip_queue_xmit
+ */
+
+ /*
+ * 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 "perf.h"
+#include "builtin.h"
+#include "util/symbol.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 system_wide = 0;
+
+static __u64 default_event_id[MAX_COUNTERS] = {
+ EID(PERF_TYPE_SOFTWARE, PERF_COUNT_TASK_CLOCK),
+ EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CONTEXT_SWITCHES),
+ EID(PERF_TYPE_SOFTWARE, PERF_COUNT_CPU_MIGRATIONS),
+ EID(PERF_TYPE_SOFTWARE, PERF_COUNT_PAGE_FAULTS),
+
+ EID(PERF_TYPE_HARDWARE, PERF_COUNT_CPU_CYCLES),
+ EID(PERF_TYPE_HARDWARE, PERF_COUNT_INSTRUCTIONS),
+ EID(PERF_TYPE_HARDWARE, PERF_COUNT_CACHE_REFERENCES),
+ EID(PERF_TYPE_HARDWARE, PERF_COUNT_CACHE_MISSES),
+};
+static int default_interval = 100000;
+static int event_count[MAX_COUNTERS];
+static int fd[MAX_NR_CPUS][MAX_COUNTERS];
+
+static __u64 count_filter = 100;
+
+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 use_mmap = 0;
+static int use_munmap = 0;
+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;
+
+static const unsigned int default_count[] = {
+ 1000000,
+ 1000000,
+ 10000,
+ 10000,
+ 1000000,
+ 10000,
+};
+
+/*
+ * 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 events;
+static long userspace_events;
+static const char CONSOLE_CLEAR[] = "";
+
+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, j;
+ int counter;
+ float events_per_sec = events/delay_secs;
+ float kevents_per_sec = (events-userspace_events)/delay_secs;
+ float sum_kevents = 0.0;
+ struct sym_entry *syme, *n;
+ struct rb_root tmp = RB_ROOT;
+ struct rb_node *nd;
+
+ events = userspace_events = 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_kevents += 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);
+ }
+
+ write(1, CONSOLE_CLEAR, strlen(CONSOLE_CLEAR));
+
+ printf(
+"------------------------------------------------------------------------------\n");
+ printf( " KernelTop:%8.0f irqs/sec kernel:%4.1f%% [",
+ events_per_sec,
+ 100.0 - (100.0*((events_per_sec-kevents_per_sec)/events_per_sec)));
+
+ if (nr_counters == 1)
+ printf("%d ", event_count[0]);
+
+ 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(" events pcnt");
+ else
+ printf(" weight events 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);
+ float pcnt;
+
+ if (++printed > 18 || syme->snap_count < count_filter)
+ continue;
+
+ pcnt = 100.0 - (100.0 * ((sum_kevents - syme->snap_count) /
+ sum_kevents));
+
+ if (nr_counters == 1)
+ printf("%19.2f - %4.1f%% - %016llx : %s\n",
+ syme->weight, pcnt, sym->start, sym->name);
+ else
+ printf("%8.1f %10ld - %4.1f%% - %016llx : %s\n",
+ syme->weight, syme->snap_count,
+ pcnt, sym->start, sym->name);
+ }
+
+ {
+ struct pollfd stdin_poll = { .fd = 0, .events = POLLIN };
+
+ if (poll(&stdin_poll, 1, 0) == 1) {
+ printf("key pressed - exiting.\n");
+ exit(0);
+ }
+ }
+}
+
+static void *display_thread(void *arg)
+{
+ printf("KernelTop refresh period: %d seconds\n", delay_secs);
+
+ while (!sleep(delay_secs))
+ print_sym_table();
+
+ 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 events 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) != 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;
+ }
+ }
+
+ events--;
+}
+
+static void process_event(uint64_t ip, int counter)
+{
+ events++;
+
+ if (ip < min_ip || ip > max_ip) {
+ userspace_events++;
+ 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(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 screw up the events 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_RECORD_IP)
+ process_event(event->ip.ip, md->counter);
+ } else {
+ switch (event->header.type) {
+ case PERF_EVENT_MMAP:
+ case PERF_EVENT_MUNMAP:
+ printf("%s: %Lu %Lu %Lu %s\n",
+ event->header.type == PERF_EVENT_MMAP
+ ? "mmap" : "munmap",
+ event->mmap.start,
+ event->mmap.len,
+ event->mmap.pgoff,
+ event->mmap.filename);
+ break;
+ }
+ }
+ }
+
+ 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 int __cmd_top(void)
+{
+ struct perf_counter_hw_event hw_event;
+ 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;
+
+ memset(&hw_event, 0, sizeof(hw_event));
+ hw_event.config = event_id[counter];
+ hw_event.irq_period = event_count[counter];
+ hw_event.record_type = PERF_RECORD_IP | PERF_RECORD_TID;
+ hw_event.nmi = 1;
+ hw_event.mmap = use_mmap;
+ hw_event.munmap = use_munmap;
+ hw_event.freq = freq;
+
+ fd[i][counter] = sys_perf_counter_open(&hw_event, target_pid, cpu, group_fd, 0);
+ if (fd[i][counter] < 0) {
+ int err = errno;
+ printf("kerneltop 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) {
+ printf("kerneltop error: failed to mmap with %d (%s)\n",
+ errno, strerror(errno));
+ exit(-1);
+ }
+ }
+ }
+
+ 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, &param)) {
+ printf("Could not set realtime priority.\n");
+ exit(-1);
+ }
+ }
+
+ while (1) {
+ int hits = events;
+
+ for (i = 0; i < nr_cpus; i++) {
+ for (counter = 0; counter < nr_counters; counter++)
+ mmap_read(&mmap_array[i][counter]);
+ }
+
+ if (hits == events)
+ ret = poll(event_array, nr_poll, 100);
+ }
+
+ return 0;
+}
+
+static const char * const top_usage[] = {
+ "perf top [<options>]",
+ NULL
+};
+
+static char events_help_msg[EVENTS_HELP_MAX];
+
+static const struct option options[] = {
+ OPT_CALLBACK('e', "event", NULL, "event",
+ events_help_msg, 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_BOOLEAN('M', "use-mmap", &use_mmap,
+ "track mmap events"),
+ OPT_BOOLEAN('U', "use-munmap", &use_munmap,
+ "track munmap events"),
+ OPT_INTEGER('F', "--freq", &freq,
+ "profile at this frequency"),
+ OPT_END()
+};
+
+int cmd_top(int argc, const char **argv, const char *prefix)
+{
+ int counter;
+
+ page_size = sysconf(_SC_PAGE_SIZE);
+
+ create_events_help(events_help_msg);
+ memcpy(event_id, default_event_id, sizeof(default_event_id));
+
+ 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;
+ event_id[0] = 0;
+ }
+
+ for (counter = 0; counter < nr_counters; counter++) {
+ if (event_count[counter])
+ continue;
+
+ event_count[counter] = 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;
+
+ parse_symbols();
+
+ return __cmd_top();
+}
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