diff options
Diffstat (limited to 'samples/bpf/tracex3_user.c')
| -rw-r--r-- | samples/bpf/tracex3_user.c | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/samples/bpf/tracex3_user.c b/samples/bpf/tracex3_user.c new file mode 100644 index 000000000..83e0fecbb --- /dev/null +++ b/samples/bpf/tracex3_user.c @@ -0,0 +1,190 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2013-2015 PLUMgrid, http://plumgrid.com + */ +#include <stdio.h> +#include <stdlib.h> +#include <signal.h> +#include <unistd.h> +#include <stdbool.h> +#include <string.h> +#include <sys/resource.h> + +#include <bpf/bpf.h> +#include <bpf/libbpf.h> +#include "bpf_util.h" + +#define SLOTS 100 + +static void clear_stats(int fd) +{ + unsigned int nr_cpus = bpf_num_possible_cpus(); + __u64 values[nr_cpus]; + __u32 key; + + memset(values, 0, sizeof(values)); + for (key = 0; key < SLOTS; key++) + bpf_map_update_elem(fd, &key, values, BPF_ANY); +} + +const char *color[] = { + "\033[48;5;255m", + "\033[48;5;252m", + "\033[48;5;250m", + "\033[48;5;248m", + "\033[48;5;246m", + "\033[48;5;244m", + "\033[48;5;242m", + "\033[48;5;240m", + "\033[48;5;238m", + "\033[48;5;236m", + "\033[48;5;234m", + "\033[48;5;232m", +}; +const int num_colors = ARRAY_SIZE(color); + +const char nocolor[] = "\033[00m"; + +const char *sym[] = { + " ", + " ", + ".", + ".", + "*", + "*", + "o", + "o", + "O", + "O", + "#", + "#", +}; + +bool full_range = false; +bool text_only = false; + +static void print_banner(void) +{ + if (full_range) + printf("|1ns |10ns |100ns |1us |10us |100us" + " |1ms |10ms |100ms |1s |10s\n"); + else + printf("|1us |10us |100us |1ms |10ms " + "|100ms |1s |10s\n"); +} + +static void print_hist(int fd) +{ + unsigned int nr_cpus = bpf_num_possible_cpus(); + __u64 total_events = 0; + long values[nr_cpus]; + __u64 max_cnt = 0; + __u64 cnt[SLOTS]; + __u64 value; + __u32 key; + int i; + + for (key = 0; key < SLOTS; key++) { + bpf_map_lookup_elem(fd, &key, values); + value = 0; + for (i = 0; i < nr_cpus; i++) + value += values[i]; + cnt[key] = value; + total_events += value; + if (value > max_cnt) + max_cnt = value; + } + clear_stats(fd); + for (key = full_range ? 0 : 29; key < SLOTS; key++) { + int c = num_colors * cnt[key] / (max_cnt + 1); + + if (text_only) + printf("%s", sym[c]); + else + printf("%s %s", color[c], nocolor); + } + printf(" # %lld\n", total_events); +} + +int main(int ac, char **argv) +{ + struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY}; + struct bpf_link *links[2]; + struct bpf_program *prog; + struct bpf_object *obj; + char filename[256]; + int map_fd, i, j = 0; + + for (i = 1; i < ac; i++) { + if (strcmp(argv[i], "-a") == 0) { + full_range = true; + } else if (strcmp(argv[i], "-t") == 0) { + text_only = true; + } else if (strcmp(argv[i], "-h") == 0) { + printf("Usage:\n" + " -a display wider latency range\n" + " -t text only\n"); + return 1; + } + } + + if (setrlimit(RLIMIT_MEMLOCK, &r)) { + perror("setrlimit(RLIMIT_MEMLOCK)"); + return 1; + } + + snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); + obj = bpf_object__open_file(filename, NULL); + if (libbpf_get_error(obj)) { + fprintf(stderr, "ERROR: opening BPF object file failed\n"); + return 0; + } + + /* load BPF program */ + if (bpf_object__load(obj)) { + fprintf(stderr, "ERROR: loading BPF object file failed\n"); + goto cleanup; + } + + map_fd = bpf_object__find_map_fd_by_name(obj, "lat_map"); + if (map_fd < 0) { + fprintf(stderr, "ERROR: finding a map in obj file failed\n"); + goto cleanup; + } + + bpf_object__for_each_program(prog, obj) { + links[j] = bpf_program__attach(prog); + if (libbpf_get_error(links[j])) { + fprintf(stderr, "ERROR: bpf_program__attach failed\n"); + links[j] = NULL; + goto cleanup; + } + j++; + } + + printf(" heatmap of IO latency\n"); + if (text_only) + printf(" %s", sym[num_colors - 1]); + else + printf(" %s %s", color[num_colors - 1], nocolor); + printf(" - many events with this latency\n"); + + if (text_only) + printf(" %s", sym[0]); + else + printf(" %s %s", color[0], nocolor); + printf(" - few events\n"); + + for (i = 0; ; i++) { + if (i % 20 == 0) + print_banner(); + print_hist(map_fd); + sleep(2); + } + +cleanup: + for (j--; j >= 0; j--) + bpf_link__destroy(links[j]); + + bpf_object__close(obj); + return 0; +} |