| /* |
| * 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]; |
| 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); |
| |
| /* |
| * Ordering weight: count-1 * count-2 * ... / count-n |
| */ |
| static double sym_weight(const struct sym_entry *sym) |
| { |
| double weight; |
| int counter; |
| |
| weight = sym->count[0]; |
| |
| 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[] = "[H[2J"; |
| |
| static void list_insert_active_sym(struct sym_entry *syme) |
| { |
| list_add(&syme->node, &active_symbols); |
| } |
| |
| 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 (sym_weight(se) > sym_weight(iter)) |
| 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 */ |
| list_for_each_entry_safe(syme, n, &active_symbols, node) { |
| if (syme->count[0] != 0) { |
| rb_insert_active_sym(&tmp, syme); |
| sum_kevents += syme->count[0]; |
| |
| for (j = 0; j < nr_counters; j++) |
| syme->count[j] = zero ? 0 : syme->count[j] * 7 / 8; |
| } else |
| list_del_init(&syme->node); |
| } |
| |
| 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->count[0] < count_filter) |
| break; |
| |
| pcnt = 100.0 - (100.0 * ((sum_kevents - syme->count[0]) / |
| sum_kevents)); |
| |
| if (nr_counters == 1) |
| printf("%19.2f - %4.1f%% - %016llx : %s\n", |
| sym_weight(syme), |
| pcnt, sym->start, sym->name); |
| else |
| printf("%8.1f %10ld - %4.1f%% - %016llx : %s\n", |
| sym_weight(syme), syme->count[0], |
| 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->start; |
| |
| 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]++; |
| if (list_empty(&syme->node) || !syme->node.next) |
| list_insert_active_sym(syme); |
| 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, ¶m)) { |
| 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(); |
| } |