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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /samples/bpf/trace_output_user.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'samples/bpf/trace_output_user.c')
-rw-r--r-- | samples/bpf/trace_output_user.c | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/samples/bpf/trace_output_user.c b/samples/bpf/trace_output_user.c new file mode 100644 index 000000000..4837d73ed --- /dev/null +++ b/samples/bpf/trace_output_user.c @@ -0,0 +1,106 @@ +/* This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + */ +#include <stdio.h> +#include <unistd.h> +#include <stdlib.h> +#include <stdbool.h> +#include <string.h> +#include <fcntl.h> +#include <poll.h> +#include <linux/perf_event.h> +#include <linux/bpf.h> +#include <errno.h> +#include <assert.h> +#include <sys/syscall.h> +#include <sys/ioctl.h> +#include <sys/mman.h> +#include <time.h> +#include <signal.h> +#include <libbpf.h> +#include "bpf_load.h" +#include "perf-sys.h" +#include "trace_helpers.h" + +static int pmu_fd; + +static __u64 time_get_ns(void) +{ + struct timespec ts; + + clock_gettime(CLOCK_MONOTONIC, &ts); + return ts.tv_sec * 1000000000ull + ts.tv_nsec; +} + +static __u64 start_time; + +#define MAX_CNT 100000ll + +static int print_bpf_output(void *data, int size) +{ + static __u64 cnt; + struct { + __u64 pid; + __u64 cookie; + } *e = data; + + if (e->cookie != 0x12345678) { + printf("BUG pid %llx cookie %llx sized %d\n", + e->pid, e->cookie, size); + return LIBBPF_PERF_EVENT_ERROR; + } + + cnt++; + + if (cnt == MAX_CNT) { + printf("recv %lld events per sec\n", + MAX_CNT * 1000000000ll / (time_get_ns() - start_time)); + return LIBBPF_PERF_EVENT_DONE; + } + + return LIBBPF_PERF_EVENT_CONT; +} + +static void test_bpf_perf_event(void) +{ + struct perf_event_attr attr = { + .sample_type = PERF_SAMPLE_RAW, + .type = PERF_TYPE_SOFTWARE, + .config = PERF_COUNT_SW_BPF_OUTPUT, + }; + int key = 0; + + pmu_fd = sys_perf_event_open(&attr, -1/*pid*/, 0/*cpu*/, -1/*group_fd*/, 0); + + assert(pmu_fd >= 0); + assert(bpf_map_update_elem(map_fd[0], &key, &pmu_fd, BPF_ANY) == 0); + ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0); +} + +int main(int argc, char **argv) +{ + char filename[256]; + FILE *f; + int ret; + + snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); + + if (load_bpf_file(filename)) { + printf("%s", bpf_log_buf); + return 1; + } + + test_bpf_perf_event(); + + if (perf_event_mmap(pmu_fd) < 0) + return 1; + + f = popen("taskset 1 dd if=/dev/zero of=/dev/null", "r"); + (void) f; + + start_time = time_get_ns(); + ret = perf_event_poller(pmu_fd, print_bpf_output); + kill(0, SIGINT); + return ret; +} |