Merge pull request iovisor#2994 from aspsk/tcpconnect-libbpf

Tcpconnect libbpf

libbpf-tools/.gitignore

@@ -7,5 +7,6 @@
 /opensnoop
 /runqslower
 /syscount
+/tcpconnect
 /vfsstat
 /xfsslower

libbpf-tools/Makefile

@@ -18,6 +18,7 @@ APPS = \
  opensnoop \
  runqslower \
  syscount \
+ tcpconnect \
  vfsstat \
  xfsslower \
  #
@@ -26,6 +27,7 @@ COMMON_OBJ = \
  $(OUTPUT)/trace_helpers.o \
  $(OUTPUT)/syscall_helpers.o \
  $(OUTPUT)/errno_helpers.o \
+ $(OUTPUT)/map_helpers.o \
  #
 
 .PHONY: all

libbpf-tools/map_helpers.c

@@ -0,0 +1,106 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+// Copyright (c) 2020 Anton Protopopov
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+
+#include "map_helpers.h"
+
+#define warn(...) fprintf(stderr, __VA_ARGS__)
+
+static bool batch_map_ops = true; /* hope for the best */
+
+static int
+dump_hash_iter(int map_fd, void *keys, __u32 key_size,
+ void *values, __u32 value_size, __u32 *count,
+ void *invalid_key)
+{
+ __u8 key[key_size], next_key[key_size];
+ __u32 n = 0;
+ int err;
+
+ /* First get keys */
+ __builtin_memcpy(key, invalid_key, key_size);
+ while (n < *count) {
+ err = bpf_map_get_next_key(map_fd, key, next_key);
+ if (err && errno != ENOENT) {
+ return -1;
+ } else if (err) {
+ break;
+ }
+ __builtin_memcpy(key, next_key, key_size);
+ __builtin_memcpy(keys + key_size * n, next_key, key_size);
+ n++;
+ }
+
+ /* Now read values */
+ for (int i = 0; i < n; i++) {
+ err = bpf_map_lookup_elem(map_fd, keys + key_size * i,
+ values + value_size * i);
+ if (err)
+ return -1;
+ }
+
+ *count = n;
+ return 0;
+}
+
+static int
+dump_hash_batch(int map_fd, void *keys, __u32 key_size,
+ void *values, __u32 value_size, __u32 *count)
+{
+ void *in = NULL, *out;
+ __u32 n, n_read = 0;
+ int err = 0;
+
+ while (n_read < *count && !err) {
+ n = *count - n_read;
+ err = bpf_map_lookup_batch(map_fd, &in, &out,
+ keys + n_read * key_size,
+ values + n_read * value_size,
+ &n, NULL);
+ if (err && errno != ENOENT) {
+ return -1;
+ }
+ n_read += n;
+ in = out;
+ }
+
+ *count = n_read;
+ return 0;
+}
+
+int dump_hash(int map_fd,
+ void *keys, __u32 key_size,
+ void *values, __u32 value_size,
+ __u32 *count, void *invalid_key)
+{
+ int err;
+
+ if (!keys || !values || !count || !key_size || !value_size) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ if (batch_map_ops) {
+ err = dump_hash_batch(map_fd, keys, key_size,
+ values, value_size, count);
+ if (err) {
+ if (errno != EINVAL) {
+ return -1;
+
+ /* assume that batch operations are not
+ * supported and try non-batch mode */
+ batch_map_ops = false;
+ }
+ }
+ }
+
+ if (!invalid_key) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ return dump_hash_iter(map_fd, keys, key_size,
+ values, value_size, count, invalid_key);
+}

libbpf-tools/map_helpers.h

@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
+/* Copyright (c) 2020 Anton Protopopov */
+#ifndef __MAP_HELPERS_H
+#define __MAP_HELPERS_H
+
+#include <bpf/bpf.h>
+
+int dump_hash(int map_fd, void *keys, __u32 key_size,
+ void *values, __u32 value_size, __u32 *count, void *invalid_key);
+
+#endif /* __MAP_HELPERS_H */

libbpf-tools/maps.bpf.h

@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+// Copyright (c) 2020 Anton Protopopov
+#ifndef __MAPS_BPF_H
+#define __MAPS_BPF_H
+
+#include <bpf/bpf_helpers.h>
+#include <errno.h>
+
+static __always_inline void *
+bpf_map_lookup_or_try_init(void *map, const void *key, const void *init)
+{
+ void *val;
+ long err;
+
+ val = bpf_map_lookup_elem(map, key);
+ if (val)
+ return val;
+
+ err = bpf_map_update_elem(map, key, init, BPF_NOEXIST);
+ if (err && err != -EEXIST)
+ return 0;
+
+ return bpf_map_lookup_elem(map, key);
+}
+
+#endif /* __MAPS_BPF_H */

libbpf-tools/syscount.bpf.c

@@ -7,6 +7,7 @@
 #include <bpf/bpf_tracing.h>
 #include <bpf/bpf_core_read.h>
 #include "syscount.h"
+#include "maps.bpf.h"
 
 const volatile bool count_by_process = false;
 const volatile bool measure_latency = false;
@@ -30,23 +31,6 @@ struct {
  __uint(map_flags, BPF_F_NO_PREALLOC);
 } data SEC(".maps");
 
-static __always_inline
-void *bpf_map_lookup_or_try_init(void *map, void *key, const void *init)
-{
- void *val;
- int err;
-
- val = bpf_map_lookup_elem(map, key);
- if (val)
- return val;
-
- err = bpf_map_update_elem(map, key, init, 0);
- if (err)
- return (void *) 0;
-
- return bpf_map_lookup_elem(map, key);
-}
-
 static __always_inline
 void save_proc_name(struct data_t *val)
 {

libbpf-tools/syscount.c

@@ -434,7 +434,7 @@ int main(int argc, char **argv)
  }
 
  if (signal(SIGINT, sig_int) == SIG_ERR) {
- warn("can't set signal handler: %s\n", strerror(-errno));
+ warn("can't set signal handler: %s\n", strerror(errno));
  goto cleanup_obj;
  }