| // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) |
| // Copyright (c) 2020 Wenbo Zhang |
| // |
| // Based on llcstat(8) from BCC by Teng Qin. |
| // 29-Sep-2020 Wenbo Zhang Created this. |
| // 20-Jun-2022 YeZhengMao Added tid info. |
| #include <argp.h> |
| #include <signal.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <unistd.h> |
| #include <linux/perf_event.h> |
| #include <asm/unistd.h> |
| #include <bpf/libbpf.h> |
| #include <bpf/bpf.h> |
| #include "llcstat.h" |
| #include "llcstat.skel.h" |
| #include "btf_helpers.h" |
| #include "trace_helpers.h" |
| |
| struct env { |
| int sample_period; |
| time_t duration; |
| bool verbose; |
| bool per_thread; |
| } env = { |
| .sample_period = 100, |
| .duration = 10, |
| }; |
| |
| static volatile bool exiting; |
| |
| const char *argp_program_version = "llcstat 0.1"; |
| const char *argp_program_bug_address = |
| "https://github.com/iovisor/bcc/tree/master/libbpf-tools"; |
| const char argp_program_doc[] = |
| "Summarize cache references and misses by PID.\n" |
| "\n" |
| "USAGE: llcstat [--help] [-c SAMPLE_PERIOD] [duration]\n"; |
| |
| static const struct argp_option opts[] = { |
| { "sample_period", 'c', "SAMPLE_PERIOD", 0, "Sample one in this many " |
| "number of cache reference / miss events" }, |
| { "verbose", 'v', NULL, 0, "Verbose debug output" }, |
| { "tid", 't', NULL, 0, |
| "Summarize cache references and misses by PID/TID" }, |
| { NULL, 'h', NULL, OPTION_HIDDEN, "Show the full help" }, |
| {}, |
| }; |
| |
| static error_t parse_arg(int key, char *arg, struct argp_state *state) |
| { |
| static int pos_args; |
| |
| switch (key) { |
| case 'h': |
| argp_state_help(state, stderr, ARGP_HELP_STD_HELP); |
| break; |
| case 'v': |
| env.verbose = true; |
| break; |
| case 't': |
| env.per_thread = true; |
| break; |
| case 'c': |
| errno = 0; |
| env.sample_period = strtol(arg, NULL, 10); |
| if (errno) { |
| fprintf(stderr, "invalid sample period\n"); |
| argp_usage(state); |
| } |
| break; |
| case ARGP_KEY_ARG: |
| if (pos_args++) { |
| fprintf(stderr, |
| "unrecognized positional argument: %s\n", arg); |
| argp_usage(state); |
| } |
| errno = 0; |
| env.duration = strtol(arg, NULL, 10); |
| if (errno) { |
| fprintf(stderr, "invalid duration\n"); |
| argp_usage(state); |
| } |
| break; |
| default: |
| return ARGP_ERR_UNKNOWN; |
| } |
| return 0; |
| } |
| |
| static int nr_cpus; |
| |
| static int open_and_attach_perf_event(__u64 config, int period, |
| struct bpf_program *prog, |
| struct bpf_link *links[]) |
| { |
| struct perf_event_attr attr = { |
| .type = PERF_TYPE_HARDWARE, |
| .freq = 0, |
| .sample_period = period, |
| .config = config, |
| }; |
| int i, fd; |
| |
| for (i = 0; i < nr_cpus; i++) { |
| fd = syscall(__NR_perf_event_open, &attr, -1, i, -1, 0); |
| if (fd < 0) { |
| /* Ignore CPU that is offline */ |
| if (errno == ENODEV) |
| continue; |
| fprintf(stderr, "failed to init perf sampling: %s\n", |
| strerror(errno)); |
| return -1; |
| } |
| links[i] = bpf_program__attach_perf_event(prog, fd); |
| if (!links[i]) { |
| fprintf(stderr, "failed to attach perf event on cpu: %d\n", i); |
| close(fd); |
| return -1; |
| } |
| } |
| return 0; |
| } |
| |
| static int libbpf_print_fn(enum libbpf_print_level level, const char *format, va_list args) |
| { |
| if (level == LIBBPF_DEBUG && !env.verbose) |
| return 0; |
| return vfprintf(stderr, format, args); |
| } |
| |
| static void sig_handler(int sig) |
| { |
| exiting = true; |
| } |
| |
| static void print_map(struct bpf_map *map) |
| { |
| __u64 total_ref = 0, total_miss = 0, total_hit, hit; |
| __u32 pid, cpu, tid; |
| struct key_info lookup_key = { .cpu = -1 }, next_key; |
| int err, fd = bpf_map__fd(map); |
| struct value_info info; |
| |
| while (!bpf_map_get_next_key(fd, &lookup_key, &next_key)) { |
| err = bpf_map_lookup_elem(fd, &next_key, &info); |
| if (err < 0) { |
| fprintf(stderr, "failed to lookup infos: %d\n", err); |
| return; |
| } |
| hit = info.ref > info.miss ? info.ref - info.miss : 0; |
| cpu = next_key.cpu; |
| pid = next_key.pid; |
| tid = next_key.tid; |
| printf("%-8u ", pid); |
| if (env.per_thread) { |
| printf("%-8u ", tid); |
| } |
| printf("%-16s %-4u %12llu %12llu %6.2f%%\n", |
| info.comm, cpu, info.ref, info.miss, |
| info.ref > 0 ? hit * 1.0 / info.ref * 100 : 0); |
| total_miss += info.miss; |
| total_ref += info.ref; |
| lookup_key = next_key; |
| } |
| total_hit = total_ref > total_miss ? total_ref - total_miss : 0; |
| printf("Total References: %llu Total Misses: %llu Hit Rate: %.2f%%\n", |
| total_ref, total_miss, total_ref > 0 ? |
| total_hit * 1.0 / total_ref * 100 : 0); |
| |
| lookup_key.cpu = -1; |
| while (!bpf_map_get_next_key(fd, &lookup_key, &next_key)) { |
| err = bpf_map_delete_elem(fd, &next_key); |
| if (err < 0) { |
| fprintf(stderr, "failed to cleanup infos: %d\n", err); |
| return; |
| } |
| lookup_key = next_key; |
| } |
| } |
| |
| int main(int argc, char **argv) |
| { |
| struct bpf_link **rlinks = NULL, **mlinks = NULL; |
| LIBBPF_OPTS(bpf_object_open_opts, open_opts); |
| static const struct argp argp = { |
| .options = opts, |
| .parser = parse_arg, |
| .doc = argp_program_doc, |
| }; |
| struct llcstat_bpf *obj; |
| int err, i; |
| |
| err = argp_parse(&argp, argc, argv, 0, NULL, NULL); |
| if (err) |
| return err; |
| |
| libbpf_set_print(libbpf_print_fn); |
| |
| nr_cpus = libbpf_num_possible_cpus(); |
| if (nr_cpus < 0) { |
| fprintf(stderr, "failed to get # of possible cpus: '%s'!\n", |
| strerror(-nr_cpus)); |
| return 1; |
| } |
| mlinks = calloc(nr_cpus, sizeof(*mlinks)); |
| rlinks = calloc(nr_cpus, sizeof(*rlinks)); |
| if (!mlinks || !rlinks) { |
| fprintf(stderr, "failed to alloc mlinks or rlinks\n"); |
| return 1; |
| } |
| |
| err = ensure_core_btf(&open_opts); |
| if (err) { |
| fprintf(stderr, "failed to fetch necessary BTF for CO-RE: %s\n", strerror(-err)); |
| return 1; |
| } |
| |
| obj = llcstat_bpf__open_opts(&open_opts); |
| if (!obj) { |
| fprintf(stderr, "failed to open and/or load BPF object\n"); |
| goto cleanup; |
| } |
| |
| obj->rodata->targ_per_thread = env.per_thread; |
| |
| err = llcstat_bpf__load(obj); |
| if (err) { |
| fprintf(stderr, "failed to load BPF object: %d\n", err); |
| goto cleanup; |
| } |
| |
| if (open_and_attach_perf_event(PERF_COUNT_HW_CACHE_MISSES, |
| env.sample_period, |
| obj->progs.on_cache_miss, mlinks)) |
| goto cleanup; |
| if (open_and_attach_perf_event(PERF_COUNT_HW_CACHE_REFERENCES, |
| env.sample_period, |
| obj->progs.on_cache_ref, rlinks)) |
| goto cleanup; |
| |
| printf("Running for %ld seconds or Hit Ctrl-C to end.\n", env.duration); |
| |
| signal(SIGINT, sig_handler); |
| |
| sleep(env.duration); |
| |
| printf("%-8s ", "PID"); |
| if (env.per_thread) { |
| printf("%-8s ", "TID"); |
| } |
| printf("%-16s %-4s %12s %12s %7s\n", |
| "NAME", "CPU", "REFERENCE", "MISS", "HIT%"); |
| |
| print_map(obj->maps.infos); |
| |
| cleanup: |
| for (i = 0; i < nr_cpus; i++) { |
| bpf_link__destroy(mlinks[i]); |
| bpf_link__destroy(rlinks[i]); |
| } |
| free(mlinks); |
| free(rlinks); |
| llcstat_bpf__destroy(obj); |
| cleanup_core_btf(&open_opts); |
| |
| return err != 0; |
| } |