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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /samples/bpf/offwaketime_user.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'samples/bpf/offwaketime_user.c')
-rw-r--r-- | samples/bpf/offwaketime_user.c | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/samples/bpf/offwaketime_user.c b/samples/bpf/offwaketime_user.c new file mode 100644 index 0000000000..5557b53936 --- /dev/null +++ b/samples/bpf/offwaketime_user.c @@ -0,0 +1,153 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2016 Facebook + */ +#include <stdio.h> +#include <unistd.h> +#include <stdlib.h> +#include <signal.h> +#include <linux/perf_event.h> +#include <errno.h> +#include <stdbool.h> +#include <bpf/libbpf.h> +#include <bpf/bpf.h> +#include "trace_helpers.h" + +#define PRINT_RAW_ADDR 0 + +/* counts, stackmap */ +static int map_fd[2]; + +static void print_ksym(__u64 addr) +{ + struct ksym *sym; + + if (!addr) + return; + sym = ksym_search(addr); + if (!sym) { + printf("ksym not found. Is kallsyms loaded?\n"); + return; + } + + if (PRINT_RAW_ADDR) + printf("%s/%llx;", sym->name, addr); + else + printf("%s;", sym->name); +} + +#define TASK_COMM_LEN 16 + +struct key_t { + char waker[TASK_COMM_LEN]; + char target[TASK_COMM_LEN]; + __u32 wret; + __u32 tret; +}; + +static void print_stack(struct key_t *key, __u64 count) +{ + __u64 ip[PERF_MAX_STACK_DEPTH] = {}; + static bool warned; + int i; + + printf("%s;", key->target); + if (bpf_map_lookup_elem(map_fd[1], &key->tret, ip) != 0) { + printf("---;"); + } else { + for (i = PERF_MAX_STACK_DEPTH - 1; i >= 0; i--) + print_ksym(ip[i]); + } + printf("-;"); + if (bpf_map_lookup_elem(map_fd[1], &key->wret, ip) != 0) { + printf("---;"); + } else { + for (i = 0; i < PERF_MAX_STACK_DEPTH; i++) + print_ksym(ip[i]); + } + printf(";%s %lld\n", key->waker, count); + + if ((key->tret == -EEXIST || key->wret == -EEXIST) && !warned) { + printf("stackmap collisions seen. Consider increasing size\n"); + warned = true; + } else if (((int)(key->tret) < 0 || (int)(key->wret) < 0)) { + printf("err stackid %d %d\n", key->tret, key->wret); + } +} + +static void print_stacks(int fd) +{ + struct key_t key = {}, next_key; + __u64 value; + + while (bpf_map_get_next_key(fd, &key, &next_key) == 0) { + bpf_map_lookup_elem(fd, &next_key, &value); + print_stack(&next_key, value); + key = next_key; + } +} + +static void int_exit(int sig) +{ + print_stacks(map_fd[0]); + exit(0); +} + +int main(int argc, char **argv) +{ + struct bpf_object *obj = NULL; + struct bpf_link *links[2]; + struct bpf_program *prog; + int delay = 1, i = 0; + char filename[256]; + + if (load_kallsyms()) { + printf("failed to process /proc/kallsyms\n"); + return 2; + } + + snprintf(filename, sizeof(filename), "%s.bpf.o", argv[0]); + obj = bpf_object__open_file(filename, NULL); + if (libbpf_get_error(obj)) { + fprintf(stderr, "ERROR: opening BPF object file failed\n"); + obj = NULL; + goto cleanup; + } + + /* load BPF program */ + if (bpf_object__load(obj)) { + fprintf(stderr, "ERROR: loading BPF object file failed\n"); + goto cleanup; + } + + map_fd[0] = bpf_object__find_map_fd_by_name(obj, "counts"); + map_fd[1] = bpf_object__find_map_fd_by_name(obj, "stackmap"); + if (map_fd[0] < 0 || map_fd[1] < 0) { + fprintf(stderr, "ERROR: finding a map in obj file failed\n"); + goto cleanup; + } + + signal(SIGINT, int_exit); + signal(SIGTERM, int_exit); + + bpf_object__for_each_program(prog, obj) { + links[i] = bpf_program__attach(prog); + if (libbpf_get_error(links[i])) { + fprintf(stderr, "ERROR: bpf_program__attach failed\n"); + links[i] = NULL; + goto cleanup; + } + i++; + } + + if (argc > 1) + delay = atoi(argv[1]); + sleep(delay); + print_stacks(map_fd[0]); + +cleanup: + for (i--; i >= 0; i--) + bpf_link__destroy(links[i]); + + bpf_object__close(obj); + return 0; +} |