return -1;
}
-static int
-map_parse_fd_and_info(int *argc, char ***argv, void *info, __u32 *info_len)
+int map_parse_fd_and_info(int *argc, char ***argv, void *info, __u32 *info_len)
{
int err;
int fd;
fprintf(stderr,
"Usage: %s %s { show | list } [MAP]\n"
- " %s %s dump MAP\n"
- " %s %s update MAP key DATA value VALUE [UPDATE_FLAGS]\n"
- " %s %s lookup MAP key DATA\n"
- " %s %s getnext MAP [key DATA]\n"
- " %s %s delete MAP key DATA\n"
- " %s %s pin MAP FILE\n"
+ " %s %s dump MAP\n"
+ " %s %s update MAP key DATA value VALUE [UPDATE_FLAGS]\n"
+ " %s %s lookup MAP key DATA\n"
+ " %s %s getnext MAP [key DATA]\n"
+ " %s %s delete MAP key DATA\n"
+ " %s %s pin MAP FILE\n"
+ " %s %s event_pipe MAP [cpu N index M]\n"
" %s %s help\n"
"\n"
" MAP := { id MAP_ID | pinned FILE }\n"
"",
bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2],
bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2],
- bin_name, argv[-2], bin_name, argv[-2]);
+ bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2]);
return 0;
}
{ "getnext", do_getnext },
{ "delete", do_delete },
{ "pin", do_pin },
+ { "event_pipe", do_event_pipe },
{ 0 }
};
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2018 Netronome Systems, Inc. */
+/* 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 <errno.h>
+#include <fcntl.h>
+#include <libbpf.h>
+#include <poll.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <linux/bpf.h>
+#include <linux/perf_event.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/syscall.h>
+
+#include <bpf.h>
+#include <perf-sys.h>
+
+#include "main.h"
+
+#define MMAP_PAGE_CNT 16
+
+static bool stop;
+
+struct event_ring_info {
+ int fd;
+ int key;
+ unsigned int cpu;
+ void *mem;
+};
+
+struct perf_event_sample {
+ struct perf_event_header header;
+ __u32 size;
+ unsigned char data[];
+};
+
+static void int_exit(int signo)
+{
+ fprintf(stderr, "Stopping...\n");
+ stop = true;
+}
+
+static void
+print_bpf_output(struct event_ring_info *ring, struct perf_event_sample *e)
+{
+ struct {
+ struct perf_event_header header;
+ __u64 id;
+ __u64 lost;
+ } *lost = (void *)e;
+ struct timespec ts;
+
+ if (clock_gettime(CLOCK_MONOTONIC, &ts)) {
+ perror("Can't read clock for timestamp");
+ return;
+ }
+
+ if (json_output) {
+ jsonw_start_object(json_wtr);
+ jsonw_name(json_wtr, "timestamp");
+ jsonw_uint(json_wtr, ts.tv_sec * 1000000000ull + ts.tv_nsec);
+ jsonw_name(json_wtr, "type");
+ jsonw_uint(json_wtr, e->header.type);
+ jsonw_name(json_wtr, "cpu");
+ jsonw_uint(json_wtr, ring->cpu);
+ jsonw_name(json_wtr, "index");
+ jsonw_uint(json_wtr, ring->key);
+ if (e->header.type == PERF_RECORD_SAMPLE) {
+ jsonw_name(json_wtr, "data");
+ print_data_json(e->data, e->size);
+ } else if (e->header.type == PERF_RECORD_LOST) {
+ jsonw_name(json_wtr, "lost");
+ jsonw_start_object(json_wtr);
+ jsonw_name(json_wtr, "id");
+ jsonw_uint(json_wtr, lost->id);
+ jsonw_name(json_wtr, "count");
+ jsonw_uint(json_wtr, lost->lost);
+ jsonw_end_object(json_wtr);
+ }
+ jsonw_end_object(json_wtr);
+ } else {
+ if (e->header.type == PERF_RECORD_SAMPLE) {
+ printf("== @%ld.%ld CPU: %d index: %d =====\n",
+ (long)ts.tv_sec, ts.tv_nsec,
+ ring->cpu, ring->key);
+ fprint_hex(stdout, e->data, e->size, " ");
+ printf("\n");
+ } else if (e->header.type == PERF_RECORD_LOST) {
+ printf("lost %lld events\n", lost->lost);
+ } else {
+ printf("unknown event type=%d size=%d\n",
+ e->header.type, e->header.size);
+ }
+ }
+}
+
+static void
+perf_event_read(struct event_ring_info *ring, void **buf, size_t *buf_len)
+{
+ volatile struct perf_event_mmap_page *header = ring->mem;
+ __u64 buffer_size = MMAP_PAGE_CNT * get_page_size();
+ __u64 data_tail = header->data_tail;
+ __u64 data_head = header->data_head;
+ void *base, *begin, *end;
+
+ asm volatile("" ::: "memory"); /* in real code it should be smp_rmb() */
+ if (data_head == data_tail)
+ return;
+
+ base = ((char *)header) + get_page_size();
+
+ begin = base + data_tail % buffer_size;
+ end = base + data_head % buffer_size;
+
+ while (begin != end) {
+ struct perf_event_sample *e;
+
+ e = begin;
+ if (begin + e->header.size > base + buffer_size) {
+ long len = base + buffer_size - begin;
+
+ if (*buf_len < e->header.size) {
+ free(*buf);
+ *buf = malloc(e->header.size);
+ if (!*buf) {
+ fprintf(stderr,
+ "can't allocate memory");
+ stop = true;
+ return;
+ }
+ *buf_len = e->header.size;
+ }
+
+ memcpy(*buf, begin, len);
+ memcpy(*buf + len, base, e->header.size - len);
+ e = (void *)*buf;
+ begin = base + e->header.size - len;
+ } else if (begin + e->header.size == base + buffer_size) {
+ begin = base;
+ } else {
+ begin += e->header.size;
+ }
+
+ print_bpf_output(ring, e);
+ }
+
+ __sync_synchronize(); /* smp_mb() */
+ header->data_tail = data_head;
+}
+
+static int perf_mmap_size(void)
+{
+ return get_page_size() * (MMAP_PAGE_CNT + 1);
+}
+
+static void *perf_event_mmap(int fd)
+{
+ int mmap_size = perf_mmap_size();
+ void *base;
+
+ base = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+ if (base == MAP_FAILED) {
+ p_err("event mmap failed: %s\n", strerror(errno));
+ return NULL;
+ }
+
+ return base;
+}
+
+static void perf_event_unmap(void *mem)
+{
+ if (munmap(mem, perf_mmap_size()))
+ fprintf(stderr, "Can't unmap ring memory!\n");
+}
+
+static int bpf_perf_event_open(int map_fd, int key, int cpu)
+{
+ struct perf_event_attr attr = {
+ .sample_type = PERF_SAMPLE_RAW,
+ .type = PERF_TYPE_SOFTWARE,
+ .config = PERF_COUNT_SW_BPF_OUTPUT,
+ };
+ int pmu_fd;
+
+ pmu_fd = sys_perf_event_open(&attr, -1, cpu, -1, 0);
+ if (pmu_fd < 0) {
+ p_err("failed to open perf event %d for CPU %d", key, cpu);
+ return -1;
+ }
+
+ if (bpf_map_update_elem(map_fd, &key, &pmu_fd, BPF_ANY)) {
+ p_err("failed to update map for event %d for CPU %d", key, cpu);
+ goto err_close;
+ }
+ if (ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0)) {
+ p_err("failed to enable event %d for CPU %d", key, cpu);
+ goto err_close;
+ }
+
+ return pmu_fd;
+
+err_close:
+ close(pmu_fd);
+ return -1;
+}
+
+int do_event_pipe(int argc, char **argv)
+{
+ int i, nfds, map_fd, index = -1, cpu = -1;
+ struct bpf_map_info map_info = {};
+ struct event_ring_info *rings;
+ size_t tmp_buf_sz = 0;
+ void *tmp_buf = NULL;
+ struct pollfd *pfds;
+ __u32 map_info_len;
+ bool do_all = true;
+
+ map_info_len = sizeof(map_info);
+ map_fd = map_parse_fd_and_info(&argc, &argv, &map_info, &map_info_len);
+ if (map_fd < 0)
+ return -1;
+
+ if (map_info.type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) {
+ p_err("map is not a perf event array");
+ goto err_close_map;
+ }
+
+ while (argc) {
+ if (argc < 2)
+ BAD_ARG();
+
+ if (is_prefix(*argv, "cpu")) {
+ char *endptr;
+
+ NEXT_ARG();
+ cpu = strtoul(*argv, &endptr, 0);
+ if (*endptr) {
+ p_err("can't parse %s as CPU ID", **argv);
+ goto err_close_map;
+ }
+
+ NEXT_ARG();
+ } else if (is_prefix(*argv, "index")) {
+ char *endptr;
+
+ NEXT_ARG();
+ index = strtoul(*argv, &endptr, 0);
+ if (*endptr) {
+ p_err("can't parse %s as index", **argv);
+ goto err_close_map;
+ }
+
+ NEXT_ARG();
+ } else {
+ BAD_ARG();
+ }
+
+ do_all = false;
+ }
+
+ if (!do_all) {
+ if (index == -1 || cpu == -1) {
+ p_err("cpu and index must be specified together");
+ goto err_close_map;
+ }
+
+ nfds = 1;
+ } else {
+ nfds = min(get_possible_cpus(), map_info.max_entries);
+ cpu = 0;
+ index = 0;
+ }
+
+ rings = calloc(nfds, sizeof(rings[0]));
+ if (!rings)
+ goto err_close_map;
+
+ pfds = calloc(nfds, sizeof(pfds[0]));
+ if (!pfds)
+ goto err_free_rings;
+
+ for (i = 0; i < nfds; i++) {
+ rings[i].cpu = cpu + i;
+ rings[i].key = index + i;
+
+ rings[i].fd = bpf_perf_event_open(map_fd, rings[i].key,
+ rings[i].cpu);
+ if (rings[i].fd < 0)
+ goto err_close_fds_prev;
+
+ rings[i].mem = perf_event_mmap(rings[i].fd);
+ if (!rings[i].mem)
+ goto err_close_fds_current;
+
+ pfds[i].fd = rings[i].fd;
+ pfds[i].events = POLLIN;
+ }
+
+ signal(SIGINT, int_exit);
+ signal(SIGHUP, int_exit);
+ signal(SIGTERM, int_exit);
+
+ if (json_output)
+ jsonw_start_array(json_wtr);
+
+ while (!stop) {
+ poll(pfds, nfds, 200);
+ for (i = 0; i < nfds; i++)
+ perf_event_read(&rings[i], &tmp_buf, &tmp_buf_sz);
+ }
+ free(tmp_buf);
+
+ if (json_output)
+ jsonw_end_array(json_wtr);
+
+ for (i = 0; i < nfds; i++) {
+ perf_event_unmap(rings[i].mem);
+ close(rings[i].fd);
+ }
+ free(pfds);
+ free(rings);
+ close(map_fd);
+
+ return 0;
+
+err_close_fds_prev:
+ while (i--) {
+ perf_event_unmap(rings[i].mem);
+err_close_fds_current:
+ close(rings[i].fd);
+ }
+ free(pfds);
+err_free_rings:
+ free(rings);
+err_close_map:
+ close(map_fd);
+ return -1;
+}
projects / linux.git / commitdiff