--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Google LLC.
+ *
+ * Based on klockstat from BCC by Jiri Olsa and others
+ * 2021-10-26 Barret Rhoden Created this.
+ */
+#include "vmlinux.h"
+#include <bpf/bpf_core_read.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include "klockstat.h"
+#include "bits.bpf.h"
+
+const volatile pid_t targ_tgid = 0;
+const volatile pid_t targ_pid = 0;
+struct mutex *const volatile targ_lock = NULL;
+
+struct {
+ __uint(type, BPF_MAP_TYPE_STACK_TRACE);
+ __uint(max_entries, MAX_ENTRIES);
+ __uint(key_size, sizeof(u32));
+ __uint(value_size, PERF_MAX_STACK_DEPTH * sizeof(u64));
+} stack_map SEC(".maps");
+
+/*
+ * Uniquely identifies a task grabbing a particular lock; a task can only hold
+ * the same lock once (non-recursive mutexes).
+ */
+struct task_lock {
+ u64 task_id;
+ u64 lock_ptr;
+};
+
+struct lockholder_info {
+ s32 stack_id;
+ u64 task_id;
+ u64 try_at;
+ u64 acq_at;
+ u64 rel_at;
+};
+
+struct {
+ __uint(type, BPF_MAP_TYPE_HASH);
+ __uint(max_entries, MAX_ENTRIES);
+ __type(key, struct task_lock);
+ __type(value, struct lockholder_info);
+} lockholder_map SEC(".maps");
+
+/*
+ * Keyed by stack_id.
+ *
+ * Multiple call sites may have the same underlying lock, but we only know the
+ * stats for a particular stack frame. Multiple tasks may have the same
+ * stackframe.
+ */
+struct {
+ __uint(type, BPF_MAP_TYPE_HASH);
+ __uint(max_entries, MAX_ENTRIES);
+ __type(key, s32);
+ __type(value, struct lock_stat);
+} stat_map SEC(".maps");
+
+static bool tracing_task(u64 task_id)
+{
+ u32 tgid = task_id >> 32;
+ u32 pid = task_id;
+
+ if (targ_tgid && targ_tgid != tgid)
+ return false;
+ if (targ_pid && targ_pid != pid)
+ return false;
+ return true;
+}
+
+static void lock_contended(void *ctx, struct mutex *lock)
+{
+ u64 task_id;
+ struct lockholder_info li[1] = {0};
+ struct task_lock tl = {};
+
+ if (targ_lock && targ_lock != lock)
+ return;
+ task_id = bpf_get_current_pid_tgid();
+ if (!tracing_task(task_id))
+ return;
+
+ li->task_id = task_id;
+ /*
+ * Skip 4 frames, e.g.:
+ * __this_module+0x34ef
+ * __this_module+0x34ef
+ * __this_module+0x8c44
+ * mutex_lock+0x5
+ *
+ * Note: if you make major changes to this bpf program, double check
+ * that you aren't skipping too many frames.
+ */
+ li->stack_id = bpf_get_stackid(ctx, &stack_map,
+ 4 | BPF_F_FAST_STACK_CMP);
+ /* Legit failures include EEXIST */
+ if (li->stack_id < 0)
+ return;
+ li->try_at = bpf_ktime_get_ns();
+
+ tl.task_id = task_id;
+ tl.lock_ptr = (u64)lock;
+ bpf_map_update_elem(&lockholder_map, &tl, li, BPF_ANY);
+}
+
+static void lock_acquired(struct mutex *lock)
+{
+ u64 task_id;
+ struct lockholder_info *li;
+ struct task_lock tl = {};
+
+ if (targ_lock && targ_lock != lock)
+ return;
+ task_id = bpf_get_current_pid_tgid();
+ if (!tracing_task(task_id))
+ return;
+
+ tl.task_id = task_id;
+ tl.lock_ptr = (u64)lock;
+ li = bpf_map_lookup_elem(&lockholder_map, &tl);
+ if (!li)
+ return;
+
+ li->acq_at = bpf_ktime_get_ns();
+}
+
+static void account(struct lockholder_info *li)
+{
+ struct lock_stat *ls;
+ u64 delta;
+
+ /*
+ * Multiple threads may have the same stack_id. Even though we are
+ * holding the lock, dynamically allocated mutexes can have the same
+ * callgraph but represent different locks. They will be accounted as
+ * the same lock, which is what we want, but we need to use atomics to
+ * avoid corruption, especially for the total_time variables.
+ */
+ ls = bpf_map_lookup_elem(&stat_map, &li->stack_id);
+ if (!ls) {
+ struct lock_stat fresh = {0};
+
+ bpf_map_update_elem(&stat_map, &li->stack_id, &fresh, BPF_ANY);
+ ls = bpf_map_lookup_elem(&stat_map, &li->stack_id);
+ if (!ls)
+ return;
+ }
+
+ delta = li->acq_at - li->try_at;
+ __sync_fetch_and_add(&ls->acq_count, 1);
+ __sync_fetch_and_add(&ls->acq_total_time, delta);
+ if (delta > READ_ONCE(ls->acq_max_time)) {
+ WRITE_ONCE(ls->acq_max_time, delta);
+ WRITE_ONCE(ls->acq_max_id, li->task_id);
+ /*
+ * Potentially racy, if multiple threads think they are the max,
+ * so you may get a clobbered write.
+ */
+ bpf_get_current_comm(ls->acq_max_comm, TASK_COMM_LEN);
+ }
+
+ delta = li->rel_at - li->acq_at;
+ __sync_fetch_and_add(&ls->hld_count, 1);
+ __sync_fetch_and_add(&ls->hld_total_time, delta);
+ if (delta > READ_ONCE(ls->hld_max_time)) {
+ WRITE_ONCE(ls->hld_max_time, delta);
+ WRITE_ONCE(ls->hld_max_id, li->task_id);
+ bpf_get_current_comm(ls->hld_max_comm, TASK_COMM_LEN);
+ }
+}
+
+static void lock_released(struct mutex *lock)
+{
+ u64 task_id;
+ struct lockholder_info *li;
+ struct task_lock tl = {};
+
+ if (targ_lock && targ_lock != lock)
+ return;
+ task_id = bpf_get_current_pid_tgid();
+ if (!tracing_task(task_id))
+ return;
+ tl.task_id = task_id;
+ tl.lock_ptr = (u64)lock;
+ li = bpf_map_lookup_elem(&lockholder_map, &tl);
+ if (!li)
+ return;
+
+ li->rel_at = bpf_ktime_get_ns();
+ account(li);
+
+ bpf_map_delete_elem(&lockholder_map, &tl);
+}
+
+SEC("fentry/mutex_lock")
+int BPF_PROG(mutex_lock, struct mutex *lock)
+{
+ lock_contended(ctx, lock);
+ return 0;
+}
+
+SEC("fexit/mutex_lock")
+int BPF_PROG(mutex_lock_exit, struct mutex *lock, long ret)
+{
+ lock_acquired(lock);
+ return 0;
+}
+
+SEC("fexit/mutex_trylock")
+int BPF_PROG(mutex_trylock_exit, struct mutex *lock, long ret)
+{
+ if (ret) {
+ lock_contended(ctx, lock);
+ lock_acquired(lock);
+ }
+ return 0;
+}
+
+SEC("fentry/mutex_unlock")
+int BPF_PROG(mutex_unlock, struct mutex *lock)
+{
+ lock_released(lock);
+ return 0;
+}
+
+char LICENSE[] SEC("license") = "GPL";
--- /dev/null
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+/* Copyright (c) 2021 Google LLC.
+ *
+ * Based on klockstat from BCC by Jiri Olsa and others
+ * 2021-10-26 Barret Rhoden Created this.
+ */
+#include <argp.h>
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <sys/param.h>
+
+#include <bpf/libbpf.h>
+#include <bpf/bpf.h>
+#include "klockstat.h"
+#include "klockstat.skel.h"
+#include "trace_helpers.h"
+
+#define warn(...) fprintf(stderr, __VA_ARGS__)
+
+enum {
+ SORT_ACQ_MAX,
+ SORT_ACQ_COUNT,
+ SORT_ACQ_TOTAL,
+ SORT_HLD_MAX,
+ SORT_HLD_COUNT,
+ SORT_HLD_TOTAL,
+};
+
+static struct prog_env {
+ pid_t pid;
+ pid_t tid;
+ char *caller;
+ char *lock_name;
+ unsigned int nr_locks;
+ unsigned int nr_stack_entries;
+ unsigned int sort_acq;
+ unsigned int sort_hld;
+ unsigned int duration;
+ unsigned int interval;
+ unsigned int iterations;
+ bool reset;
+ bool timestamp;
+} env = {
+ .nr_locks = 99999999,
+ .nr_stack_entries = 1,
+ .sort_acq = SORT_ACQ_MAX,
+ .sort_hld = SORT_HLD_MAX,
+ .interval = 99999999,
+ .iterations = 99999999,
+};
+
+const char *argp_program_version = "klockstat 0.1";
+const char *argp_program_bug_address =
+ "https://github.com/iovisor/bcc/tree/master/libbpf-tools";
+static const char args_doc[] = "FUNCTION";
+static const char program_doc[] =
+"Trace mutex lock acquisition and hold times, in nsec\n"
+"\n"
+"Usage: klockstat [-hRT] [-p PID] [-t TID] [-c FUNC] [-L LOCK] [-n NR_LOCKS]\n"
+" [-s NR_STACKS] [-S SORT] [-d DURATION] [-i INTERVAL]\n"
+"\v"
+"Examples:\n"
+" klockstat # trace system wide until ctrl-c\n"
+" klockstat -d 5 # trace for 5 seconds\n"
+" klockstat -i 5 # print stats every 5 seconds\n"
+" klockstat -p 181 # trace process 181 only\n"
+" klockstat -t 181 # trace thread 181 only\n"
+" klockstat -c pipe_ # print only for lock callers with 'pipe_'\n"
+" # prefix\n"
+" klockstat -L cgroup_mutex # trace the cgroup_mutex lock only\n"
+" klockstat -S acq_count # sort lock acquired results by acquire count\n"
+" klockstat -S hld_total # sort lock held results by total held time\n"
+" klockstat -S acq_count,hld_total # combination of above\n"
+" klockstat -n 3 # display top 3 locks\n"
+" klockstat -s 6 # display 6 stack entries per lock\n"
+;
+
+static const struct argp_option opts[] = {
+ { "pid", 'p', "PID", 0, "Filter by process ID" },
+ { "tid", 't', "TID", 0, "Filter by thread ID" },
+ { 0, 0, 0, 0, "" },
+ { "caller", 'c', "FUNC", 0, "Filter by caller string prefix" },
+ { "lock", 'L', "LOCK", 0, "Filter by specific ksym lock name" },
+ { 0, 0, 0, 0, "" },
+ { "locks", 'n', "NR_LOCKS", 0, "Number of locks to print" },
+ { "stacks", 's', "NR_STACKS", 0, "Number of stack entries to print per lock" },
+ { "sort", 'S', "SORT", 0, "Sort by field:\n acq_[max|total|count]\n hld_[max|total|count]" },
+ { 0, 0, 0, 0, "" },
+ { "duration", 'd', "SECONDS", 0, "Duration to trace" },
+ { "interval", 'i', "SECONDS", 0, "Print interval" },
+ { "reset", 'R', NULL, 0, "Reset stats each interval" },
+ { "timestamp", 'T', NULL, 0, "Print timestamp" },
+
+ { NULL, 'h', NULL, OPTION_HIDDEN, "Show the full help" },
+ {},
+};
+
+static bool parse_one_sort(struct prog_env *env, const char *sort)
+{
+ const char *field = sort + 4;
+
+ if (!strncmp(sort, "acq_", 4)) {
+ if (!strcmp(field, "max")) {
+ env->sort_acq = SORT_ACQ_MAX;
+ return true;
+ } else if (!strcmp(field, "total")) {
+ env->sort_acq = SORT_ACQ_TOTAL;
+ return true;
+ } else if (!strcmp(field, "count")) {
+ env->sort_acq = SORT_ACQ_COUNT;
+ return true;
+ }
+ } else if (!strncmp(sort, "hld_", 4)) {
+ if (!strcmp(field, "max")) {
+ env->sort_hld = SORT_HLD_MAX;
+ return true;
+ } else if (!strcmp(field, "total")) {
+ env->sort_hld = SORT_HLD_TOTAL;
+ return true;
+ } else if (!strcmp(field, "count")) {
+ env->sort_hld = SORT_HLD_COUNT;
+ return true;
+ }
+ }
+
+ return false;
+}
+
+static bool parse_sorts(struct prog_env *env, char *arg)
+{
+ char *comma = strchr(arg, ',');
+
+ if (comma) {
+ *comma = '\0';
+ comma++;
+ if (!parse_one_sort(env, comma))
+ return false;
+ }
+ return parse_one_sort(env, arg);
+}
+
+static error_t parse_arg(int key, char *arg, struct argp_state *state)
+{
+ struct prog_env *env = state->input;
+ long duration, interval;
+
+ switch (key) {
+ case 'p':
+ errno = 0;
+ env->pid = strtol(arg, NULL, 10);
+ if (errno || env->pid <= 0) {
+ warn("Invalid PID: %s\n", arg);
+ argp_usage(state);
+ }
+ break;
+ case 't':
+ errno = 0;
+ env->tid = strtol(arg, NULL, 10);
+ if (errno || env->tid <= 0) {
+ warn("Invalid TID: %s\n", arg);
+ argp_usage(state);
+ }
+ break;
+ case 'c':
+ env->caller = arg;
+ break;
+ case 'L':
+ env->lock_name = arg;
+ break;
+ case 'n':
+ errno = 0;
+ env->nr_locks = strtol(arg, NULL, 10);
+ if (errno || env->nr_locks <= 0) {
+ warn("Invalid NR_LOCKS: %s\n", arg);
+ argp_usage(state);
+ }
+ break;
+ case 's':
+ errno = 0;
+ env->nr_stack_entries = strtol(arg, NULL, 10);
+ if (errno || env->nr_stack_entries <= 0) {
+ warn("Invalid NR_STACKS: %s\n", arg);
+ argp_usage(state);
+ }
+ break;
+ case 'S':
+ if (!parse_sorts(env, arg)) {
+ warn("Bad sort string: %s\n", arg);
+ argp_usage(state);
+ }
+ break;
+ case 'd':
+ errno = 0;
+ duration = strtol(arg, NULL, 10);
+ if (errno || duration <= 0) {
+ warn("Invalid duration: %s\n", arg);
+ argp_usage(state);
+ }
+ env->duration = duration;
+ break;
+ case 'i':
+ errno = 0;
+ interval = strtol(arg, NULL, 10);
+ if (errno || interval <= 0) {
+ warn("Invalid interval: %s\n", arg);
+ argp_usage(state);
+ }
+ env->interval = interval;
+ break;
+ case 'R':
+ env->reset = true;
+ break;
+ case 'T':
+ env->timestamp = true;
+ break;
+ case 'h':
+ argp_state_help(state, stderr, ARGP_HELP_STD_HELP);
+ break;
+ case ARGP_KEY_END:
+ if (env->duration) {
+ if (env->interval > env->duration)
+ env->interval = env->duration;
+ env->iterations = env->duration / env->interval;
+ }
+ break;
+ default:
+ return ARGP_ERR_UNKNOWN;
+ }
+ return 0;
+}
+
+struct stack_stat {
+ uint32_t stack_id;
+ struct lock_stat ls;
+ uint64_t bt[PERF_MAX_STACK_DEPTH];
+};
+
+static bool caller_is_traced(struct ksyms *ksyms, uint64_t caller_pc)
+{
+ const struct ksym *ksym;
+
+ if (!env.caller)
+ return true;
+ ksym = ksyms__map_addr(ksyms, caller_pc);
+ if (!ksym)
+ return true;
+ return strncmp(env.caller, ksym->name, strlen(env.caller)) == 0;
+}
+
+static int larger_first(uint64_t x, uint64_t y)
+{
+ if (x > y)
+ return -1;
+ if (x == y)
+ return 0;
+ return 1;
+}
+
+static int sort_by_acq(const void *x, const void *y)
+{
+ struct stack_stat *ss_x = *(struct stack_stat**)x;
+ struct stack_stat *ss_y = *(struct stack_stat**)y;
+
+ switch (env.sort_acq) {
+ case SORT_ACQ_MAX:
+ return larger_first(ss_x->ls.acq_max_time,
+ ss_y->ls.acq_max_time);
+ case SORT_ACQ_COUNT:
+ return larger_first(ss_x->ls.acq_count,
+ ss_y->ls.acq_count);
+ case SORT_ACQ_TOTAL:
+ return larger_first(ss_x->ls.acq_total_time,
+ ss_y->ls.acq_total_time);
+ }
+
+ warn("bad sort_acq %d\n", env.sort_acq);
+ return -1;
+}
+
+static int sort_by_hld(const void *x, const void *y)
+{
+ struct stack_stat *ss_x = *(struct stack_stat**)x;
+ struct stack_stat *ss_y = *(struct stack_stat**)y;
+
+ switch (env.sort_hld) {
+ case SORT_HLD_MAX:
+ return larger_first(ss_x->ls.hld_max_time,
+ ss_y->ls.hld_max_time);
+ case SORT_HLD_COUNT:
+ return larger_first(ss_x->ls.hld_count,
+ ss_y->ls.hld_count);
+ case SORT_HLD_TOTAL:
+ return larger_first(ss_x->ls.hld_total_time,
+ ss_y->ls.hld_total_time);
+ }
+
+ warn("bad sort_hld %d\n", env.sort_hld);
+ return -1;
+}
+
+static char *symname(struct ksyms *ksyms, uint64_t pc, char *buf, size_t n)
+{
+ const struct ksym *ksym = ksyms__map_addr(ksyms, pc);
+
+ if (!ksym)
+ return "Unknown";
+ snprintf(buf, n, "%s+0x%lx", ksym->name, pc - ksym->addr);
+ return buf;
+}
+
+static void print_acq_header(void)
+{
+ printf("\n Caller Avg Spin Count Max Spin Total Spin\n");
+}
+
+static void print_acq_stat(struct ksyms *ksyms, struct stack_stat *ss,
+ int nr_stack_entries)
+{
+ char buf[40];
+ int i;
+
+ printf("%37s %9llu %8llu %10llu %12llu\n",
+ symname(ksyms, ss->bt[0], buf, sizeof(buf)),
+ ss->ls.acq_total_time / ss->ls.acq_count,
+ ss->ls.acq_count,
+ ss->ls.acq_max_time,
+ ss->ls.acq_total_time);
+ for (i = 1; i < nr_stack_entries; i++) {
+ if (!ss->bt[i])
+ break;
+ printf("%37s\n", symname(ksyms, ss->bt[i], buf, sizeof(buf)));
+ }
+ if (nr_stack_entries > 1)
+ printf(" Max PID %llu, COMM %s\n",
+ ss->ls.acq_max_id >> 32,
+ ss->ls.acq_max_comm);
+}
+
+static void print_hld_header(void)
+{
+ printf("\n Caller Avg Hold Count Max Hold Total Hold\n");
+}
+
+static void print_hld_stat(struct ksyms *ksyms, struct stack_stat *ss,
+ int nr_stack_entries)
+{
+ char buf[40];
+ int i;
+
+ printf("%37s %9llu %8llu %10llu %12llu\n",
+ symname(ksyms, ss->bt[0], buf, sizeof(buf)),
+ ss->ls.hld_total_time / ss->ls.hld_count,
+ ss->ls.hld_count,
+ ss->ls.hld_max_time,
+ ss->ls.hld_total_time);
+ for (i = 1; i < nr_stack_entries; i++) {
+ if (!ss->bt[i])
+ break;
+ printf("%37s\n", symname(ksyms, ss->bt[i], buf, sizeof(buf)));
+ }
+ if (nr_stack_entries > 1)
+ printf(" Max PID %llu, COMM %s\n",
+ ss->ls.hld_max_id >> 32,
+ ss->ls.hld_max_comm);
+}
+
+static int print_stats(struct ksyms *ksyms, int stack_map, int stat_map)
+{
+ struct stack_stat **stats, *ss;
+ size_t stat_idx = 0;
+ size_t stats_sz = 1;
+ uint32_t lookup_key = 0;
+ uint32_t stack_id;
+ int ret, i;
+
+ stats = calloc(stats_sz, sizeof(void *));
+ if (!stats) {
+ warn("Out of memory\n");
+ return -1;
+ }
+
+ while (bpf_map_get_next_key(stat_map, &lookup_key, &stack_id) == 0) {
+ if (stat_idx == stats_sz) {
+ stats_sz *= 2;
+ stats = reallocarray(stats, stats_sz, sizeof(void *));
+ if (!stats) {
+ warn("Out of memory\n");
+ return -1;
+ }
+ }
+ ss = malloc(sizeof(struct stack_stat));
+ if (!ss) {
+ warn("Out of memory\n");
+ return -1;
+ }
+ ss->stack_id = stack_id;
+ if (env.reset) {
+ ret = bpf_map_lookup_and_delete_elem(stat_map,
+ &stack_id,
+ &ss->ls);
+ lookup_key = 0;
+ } else {
+ ret = bpf_map_lookup_elem(stat_map, &stack_id, &ss->ls);
+ lookup_key = stack_id;
+ }
+ if (ret) {
+ free(ss);
+ continue;
+ }
+ if (bpf_map_lookup_elem(stack_map, &stack_id, &ss->bt)) {
+ /* Can still report the results without a backtrace. */
+ warn("failed to lookup stack_id %u\n", stack_id);
+ }
+ if (!caller_is_traced(ksyms, ss->bt[0])) {
+ free(ss);
+ continue;
+ }
+ stats[stat_idx++] = ss;
+ }
+
+ qsort(stats, stat_idx, sizeof(void*), sort_by_acq);
+ for (i = 0; i < MIN(env.nr_locks, stat_idx); i++) {
+ if (i == 0 || env.nr_stack_entries > 1)
+ print_acq_header();
+ print_acq_stat(ksyms, stats[i],
+ MIN(env.nr_stack_entries, PERF_MAX_STACK_DEPTH));
+ }
+
+ qsort(stats, stat_idx, sizeof(void*), sort_by_hld);
+ for (i = 0; i < MIN(env.nr_locks, stat_idx); i++) {
+ if (i == 0 || env.nr_stack_entries > 1)
+ print_hld_header();
+ print_hld_stat(ksyms, stats[i],
+ MIN(env.nr_stack_entries, PERF_MAX_STACK_DEPTH));
+ }
+
+ for (i = 0; i < stat_idx; i++)
+ free(stats[i]);
+ free(stats);
+
+ return 0;
+}
+
+static void *get_lock_addr(struct ksyms *ksyms, const char *lock_name)
+{
+ const struct ksym *ksym = ksyms__get_symbol(ksyms, lock_name);
+
+ return ksym ? (void*)ksym->addr : NULL;
+}
+
+static volatile bool exiting;
+
+static void sig_hand(int signr)
+{
+ exiting = true;
+}
+
+static struct sigaction sigact = {.sa_handler = sig_hand};
+
+int main(int argc, char **argv)
+{
+ static const struct argp argp = {
+ .options = opts,
+ .parser = parse_arg,
+ .args_doc = args_doc,
+ .doc = program_doc,
+ };
+ struct klockstat_bpf *obj = NULL;
+ struct ksyms *ksyms = NULL;
+ int i, err;
+ struct tm *tm;
+ char ts[32];
+ time_t t;
+ void *lock_addr = NULL;
+
+ err = argp_parse(&argp, argc, argv, 0, NULL, &env);
+ if (err)
+ return err;
+
+ sigaction(SIGINT, &sigact, 0);
+
+ err = bump_memlock_rlimit();
+ if (err) {
+ warn("failed to increase rlimit: %d\n", err);
+ err = 1;
+ goto cleanup;
+ }
+
+ ksyms = ksyms__load();
+ if (!ksyms) {
+ warn("failed to load kallsyms\n");
+ err = 1;
+ goto cleanup;
+ }
+ if (env.lock_name) {
+ lock_addr = get_lock_addr(ksyms, env.lock_name);
+ if (!lock_addr) {
+ warn("failed to find lock %s\n", env.lock_name);
+ err = 1;
+ goto cleanup;
+ }
+ }
+
+ obj = klockstat_bpf__open();
+ if (!obj) {
+ warn("failed to open BPF object\n");
+ err = 1;
+ goto cleanup;
+ }
+
+ obj->rodata->targ_tgid = env.pid;
+ obj->rodata->targ_pid = env.tid;
+ obj->rodata->targ_lock = lock_addr;
+
+ err = klockstat_bpf__load(obj);
+ if (err) {
+ warn("failed to load BPF object\n");
+ return 1;
+ }
+ err = klockstat_bpf__attach(obj);
+ if (err) {
+ warn("failed to attach BPF object\n");
+ goto cleanup;
+ }
+
+ printf("Tracing mutex lock events... Hit Ctrl-C to end\n");
+
+ for (i = 0; i < env.iterations && !exiting; i++) {
+ sleep(env.interval);
+
+ printf("\n");
+ if (env.timestamp) {
+ time(&t);
+ tm = localtime(&t);
+ strftime(ts, sizeof(ts), "%H:%M:%S", tm);
+ printf("%-8s\n", ts);
+ }
+
+ if (print_stats(ksyms, bpf_map__fd(obj->maps.stack_map),
+ bpf_map__fd(obj->maps.stat_map))) {
+ warn("print_stats error, aborting.\n");
+ break;
+ }
+ }
+
+ printf("Exiting trace of mutex locks\n");
+
+cleanup:
+ klockstat_bpf__destroy(obj);
+ ksyms__free(ksyms);
+
+ return err != 0;
+}
projects / platform / upstream / bcc.git / commitdiff