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Commit 9b190f18 authored by Andrii Nakryiko's avatar Andrii Nakryiko Committed by Daniel Borkmann
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tools/bpftool: switch map event_pipe to libbpf's perf_buffer 

Switch event_pipe implementation to rely on new libbpf perf buffer API
(it's raw low-level variant).
Signed-off-by: default avatarAndrii Nakryiko <andriin@fb.com>
Acked-by: default avatarJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: default avatarYonghong Song <yhs@fb.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
parent ee5cf82c
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Inline Side-by-side
Showing with 64 additions and 137 deletions
tools/bpf/bpftool/map_perf_ring.c
View file @ 9b190f18
......@@ -28,7 +28,7 @@
#define MMAP_PAGE_CNT 16
static bool stop;
static volatile bool stop;
struct event_ring_info {
int fd;
......@@ -44,32 +44,44 @@ struct perf_event_sample {
unsigned char data[];
};
struct perf_event_lost {
struct perf_event_header header;
__u64 id;
__u64 lost;
};
static void int_exit(int signo)
{
fprintf(stderr, "Stopping...\n");
stop = true;
}
struct event_pipe_ctx {
bool all_cpus;
int cpu;
int idx;
};
static enum bpf_perf_event_ret
print_bpf_output(struct perf_event_header *event, void *private_data)
print_bpf_output(void *private_data, int cpu, struct perf_event_header *event)
{
struct perf_event_sample *e = container_of(event, struct perf_event_sample,
struct perf_event_sample *e = container_of(event,
struct perf_event_sample,
header);
struct event_ring_info *ring = private_data;
struct {
struct perf_event_header header;
__u64 id;
__u64 lost;
} *lost = (typeof(lost))event;
struct perf_event_lost *lost = container_of(event,
struct perf_event_lost,
header);
struct event_pipe_ctx *ctx = private_data;
int idx = ctx->all_cpus ? cpu : ctx->idx;
if (json_output) {
jsonw_start_object(json_wtr);
jsonw_name(json_wtr, "type");
jsonw_uint(json_wtr, e->header.type);
jsonw_name(json_wtr, "cpu");
jsonw_uint(json_wtr, ring->cpu);
jsonw_uint(json_wtr, cpu);
jsonw_name(json_wtr, "index");
jsonw_uint(json_wtr, ring->key);
jsonw_uint(json_wtr, idx);
if (e->header.type == PERF_RECORD_SAMPLE) {
jsonw_name(json_wtr, "timestamp");
jsonw_uint(json_wtr, e->time);
......@@ -89,7 +101,7 @@ print_bpf_output(struct perf_event_header *event, void *private_data)
if (e->header.type == PERF_RECORD_SAMPLE) {
printf("== @%lld.%09lld CPU: %d index: %d =====\n",
e->time / 1000000000ULL, e->time % 1000000000ULL,
ring->cpu, ring->key);
cpu, idx);
fprint_hex(stdout, e->data, e->size, " ");
printf("\n");
} else if (e->header.type == PERF_RECORD_LOST) {
......@@ -103,87 +115,25 @@ print_bpf_output(struct perf_event_header *event, void *private_data)
return LIBBPF_PERF_EVENT_CONT;
}
static void
perf_event_read(struct event_ring_info *ring, void **buf, size_t *buf_len)
{
enum bpf_perf_event_ret ret;
ret = bpf_perf_event_read_simple(ring->mem,
MMAP_PAGE_CNT * get_page_size(),
get_page_size(), buf, buf_len,
print_bpf_output, ring);
if (ret != LIBBPF_PERF_EVENT_CONT) {
fprintf(stderr, "perf read loop failed with %d\n", ret);
stop = true;
}
}
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)
int do_event_pipe(int argc, char **argv)
{
struct perf_event_attr attr = {
struct perf_event_attr perf_attr = {
.sample_type = PERF_SAMPLE_RAW | PERF_SAMPLE_TIME,
.type = PERF_TYPE_SOFTWARE,
.config = PERF_COUNT_SW_BPF_OUTPUT,
.sample_period = 1,
.wakeup_events = 1,
};
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;
struct perf_buffer_raw_opts opts = {};
struct event_pipe_ctx ctx = {
.all_cpus = true,
.cpu = -1,
.idx = -1,
};
struct perf_buffer *pb;
__u32 map_info_len;
bool do_all = true;
int err, map_fd;
map_info_len = sizeof(map_info);
map_fd = map_parse_fd_and_info(&argc, &argv, &map_info, &map_info_len);
......@@ -205,7 +155,7 @@ int do_event_pipe(int argc, char **argv)
char *endptr;
NEXT_ARG();
cpu = strtoul(*argv, &endptr, 0);
ctx.cpu = strtoul(*argv, &endptr, 0);
if (*endptr) {
p_err("can't parse %s as CPU ID", **argv);
goto err_close_map;
......@@ -216,7 +166,7 @@ int do_event_pipe(int argc, char **argv)
char *endptr;
NEXT_ARG();
index = strtoul(*argv, &endptr, 0);
ctx.idx = strtoul(*argv, &endptr, 0);
if (*endptr) {
p_err("can't parse %s as index", **argv);
goto err_close_map;
......@@ -228,45 +178,32 @@ int do_event_pipe(int argc, char **argv)
goto err_close_map;
}
do_all = false;
ctx.all_cpus = false;
}
if (!do_all) {
if (index == -1 || cpu == -1) {
if (!ctx.all_cpus) {
if (ctx.idx == -1 || ctx.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;
ctx.cpu = 0;
ctx.idx = 0;
}
rings = calloc(nfds, sizeof(rings[0]));
if (!rings)
opts.attr = &perf_attr;
opts.event_cb = print_bpf_output;
opts.ctx = &ctx;
opts.cpu_cnt = ctx.all_cpus ? 0 : 1;
opts.cpus = &ctx.cpu;
opts.map_keys = &ctx.idx;
pb = perf_buffer__new_raw(map_fd, MMAP_PAGE_CNT, &opts);
err = libbpf_get_error(pb);
if (err) {
p_err("failed to create perf buffer: %s (%d)",
strerror(err), err);
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);
......@@ -277,34 +214,24 @@ int do_event_pipe(int argc, char **argv)
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);
err = perf_buffer__poll(pb, 200);
if (err < 0 && err != -EINTR) {
p_err("perf buffer polling failed: %s (%d)",
strerror(err), err);
goto err_close_pb;
}
}
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);
perf_buffer__free(pb);
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_pb:
perf_buffer__free(pb);
err_close_map:
close(map_fd);
return -1;
......
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