Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 256 insertions, 0 deletions

diff --git a/tools/bpf/bpftool/pids.c b/tools/bpf/bpftool/pids.c
new file mode 100644
index 000000000..bb6c969a1
--- /dev/null
+++ b/tools/bpf/bpftool/pids.c
@@ -0,0 +1,256 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/* Copyright (C) 2020 Facebook */
+#include <errno.h>
+#include <linux/err.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <bpf/bpf.h>
+#include <bpf/hashmap.h>
+
+#include "main.h"
+#include "skeleton/pid_iter.h"
+
+#ifdef BPFTOOL_WITHOUT_SKELETONS
+
+int build_obj_refs_table(struct hashmap **map, enum bpf_obj_type type)
+{
+	return -ENOTSUP;
+}
+void delete_obj_refs_table(struct hashmap *map) {}
+void emit_obj_refs_plain(struct hashmap *map, __u32 id, const char *prefix) {}
+void emit_obj_refs_json(struct hashmap *map, __u32 id, json_writer_t *json_writer) {}
+
+#else /* BPFTOOL_WITHOUT_SKELETONS */
+
+#include "pid_iter.skel.h"
+
+static void add_ref(struct hashmap *map, struct pid_iter_entry *e)
+{
+	struct hashmap_entry *entry;
+	struct obj_refs *refs;
+	struct obj_ref *ref;
+	int err, i;
+	void *tmp;
+
+	hashmap__for_each_key_entry(map, entry, u32_as_hash_field(e->id)) {
+		refs = entry->value;
+
+		for (i = 0; i < refs->ref_cnt; i++) {
+			if (refs->refs[i].pid == e->pid)
+				return;
+		}
+
+		tmp = realloc(refs->refs, (refs->ref_cnt + 1) * sizeof(*ref));
+		if (!tmp) {
+			p_err("failed to re-alloc memory for ID %u, PID %d, COMM %s...",
+			      e->id, e->pid, e->comm);
+			return;
+		}
+		refs->refs = tmp;
+		ref = &refs->refs[refs->ref_cnt];
+		ref->pid = e->pid;
+		memcpy(ref->comm, e->comm, sizeof(ref->comm));
+		refs->ref_cnt++;
+
+		return;
+	}
+
+	/* new ref */
+	refs = calloc(1, sizeof(*refs));
+	if (!refs) {
+		p_err("failed to alloc memory for ID %u, PID %d, COMM %s...",
+		      e->id, e->pid, e->comm);
+		return;
+	}
+
+	refs->refs = malloc(sizeof(*refs->refs));
+	if (!refs->refs) {
+		free(refs);
+		p_err("failed to alloc memory for ID %u, PID %d, COMM %s...",
+		      e->id, e->pid, e->comm);
+		return;
+	}
+	ref = &refs->refs[0];
+	ref->pid = e->pid;
+	memcpy(ref->comm, e->comm, sizeof(ref->comm));
+	refs->ref_cnt = 1;
+	refs->has_bpf_cookie = e->has_bpf_cookie;
+	refs->bpf_cookie = e->bpf_cookie;
+
+	err = hashmap__append(map, u32_as_hash_field(e->id), refs);
+	if (err)
+		p_err("failed to append entry to hashmap for ID %u: %s",
+		      e->id, strerror(errno));
+}
+
+static int __printf(2, 0)
+libbpf_print_none(__maybe_unused enum libbpf_print_level level,
+		  __maybe_unused const char *format,
+		  __maybe_unused va_list args)
+{
+	return 0;
+}
+
+int build_obj_refs_table(struct hashmap **map, enum bpf_obj_type type)
+{
+	struct pid_iter_entry *e;
+	char buf[4096 / sizeof(*e) * sizeof(*e)];
+	struct pid_iter_bpf *skel;
+	int err, ret, fd = -1, i;
+	libbpf_print_fn_t default_print;
+
+	*map = hashmap__new(hash_fn_for_key_as_id, equal_fn_for_key_as_id, NULL);
+	if (IS_ERR(*map)) {
+		p_err("failed to create hashmap for PID references");
+		return -1;
+	}
+	set_max_rlimit();
+
+	skel = pid_iter_bpf__open();
+	if (!skel) {
+		p_err("failed to open PID iterator skeleton");
+		return -1;
+	}
+
+	skel->rodata->obj_type = type;
+
+	/* we don't want output polluted with libbpf errors if bpf_iter is not
+	 * supported
+	 */
+	default_print = libbpf_set_print(libbpf_print_none);
+	err = pid_iter_bpf__load(skel);
+	libbpf_set_print(default_print);
+	if (err) {
+		/* too bad, kernel doesn't support BPF iterators yet */
+		err = 0;
+		goto out;
+	}
+	err = pid_iter_bpf__attach(skel);
+	if (err) {
+		/* if we loaded above successfully, attach has to succeed */
+		p_err("failed to attach PID iterator: %d", err);
+		goto out;
+	}
+
+	fd = bpf_iter_create(bpf_link__fd(skel->links.iter));
+	if (fd < 0) {
+		err = -errno;
+		p_err("failed to create PID iterator session: %d", err);
+		goto out;
+	}
+
+	while (true) {
+		ret = read(fd, buf, sizeof(buf));
+		if (ret < 0) {
+			if (errno == EAGAIN)
+				continue;
+			err = -errno;
+			p_err("failed to read PID iterator output: %d", err);
+			goto out;
+		}
+		if (ret == 0)
+			break;
+		if (ret % sizeof(*e)) {
+			err = -EINVAL;
+			p_err("invalid PID iterator output format");
+			goto out;
+		}
+		ret /= sizeof(*e);
+
+		e = (void *)buf;
+		for (i = 0; i < ret; i++, e++) {
+			add_ref(*map, e);
+		}
+	}
+	err = 0;
+out:
+	if (fd >= 0)
+		close(fd);
+	pid_iter_bpf__destroy(skel);
+	return err;
+}
+
+void delete_obj_refs_table(struct hashmap *map)
+{
+	struct hashmap_entry *entry;
+	size_t bkt;
+
+	if (!map)
+		return;
+
+	hashmap__for_each_entry(map, entry, bkt) {
+		struct obj_refs *refs = entry->value;
+
+		free(refs->refs);
+		free(refs);
+	}
+
+	hashmap__free(map);
+}
+
+void emit_obj_refs_json(struct hashmap *map, __u32 id,
+			json_writer_t *json_writer)
+{
+	struct hashmap_entry *entry;
+
+	if (hashmap__empty(map))
+		return;
+
+	hashmap__for_each_key_entry(map, entry, u32_as_hash_field(id)) {
+		struct obj_refs *refs = entry->value;
+		int i;
+
+		if (refs->ref_cnt == 0)
+			break;
+
+		if (refs->has_bpf_cookie)
+			jsonw_lluint_field(json_writer, "bpf_cookie", refs->bpf_cookie);
+
+		jsonw_name(json_writer, "pids");
+		jsonw_start_array(json_writer);
+		for (i = 0; i < refs->ref_cnt; i++) {
+			struct obj_ref *ref = &refs->refs[i];
+
+			jsonw_start_object(json_writer);
+			jsonw_int_field(json_writer, "pid", ref->pid);
+			jsonw_string_field(json_writer, "comm", ref->comm);
+			jsonw_end_object(json_writer);
+		}
+		jsonw_end_array(json_writer);
+		break;
+	}
+}
+
+void emit_obj_refs_plain(struct hashmap *map, __u32 id, const char *prefix)
+{
+	struct hashmap_entry *entry;
+
+	if (hashmap__empty(map))
+		return;
+
+	hashmap__for_each_key_entry(map, entry, u32_as_hash_field(id)) {
+		struct obj_refs *refs = entry->value;
+		int i;
+
+		if (refs->ref_cnt == 0)
+			break;
+
+		if (refs->has_bpf_cookie)
+			printf("\n\tbpf_cookie %llu", (unsigned long long) refs->bpf_cookie);
+
+		printf("%s", prefix);
+		for (i = 0; i < refs->ref_cnt; i++) {
+			struct obj_ref *ref = &refs->refs[i];
+
+			printf("%s%s(%d)", i == 0 ? "" : ", ", ref->comm, ref->pid);
+		}
+		break;
+	}
+}
+
+
+#endif