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-rw-r--r--tools/bpf/bpftool/skeleton/pid_iter.bpf.c103
1 files changed, 103 insertions, 0 deletions
diff --git a/tools/bpf/bpftool/skeleton/pid_iter.bpf.c b/tools/bpf/bpftool/skeleton/pid_iter.bpf.c
new file mode 100644
index 000000000000..eb05ea53afb1
--- /dev/null
+++ b/tools/bpf/bpftool/skeleton/pid_iter.bpf.c
@@ -0,0 +1,103 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/* Copyright (c) 2020 Facebook */
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_core_read.h>
+#include <bpf/bpf_tracing.h>
+#include "pid_iter.h"
+
+/* keep in sync with the definition in main.h */
+enum bpf_obj_type {
+ BPF_OBJ_UNKNOWN,
+ BPF_OBJ_PROG,
+ BPF_OBJ_MAP,
+ BPF_OBJ_LINK,
+ BPF_OBJ_BTF,
+};
+
+extern const void bpf_link_fops __ksym;
+extern const void bpf_map_fops __ksym;
+extern const void bpf_prog_fops __ksym;
+extern const void btf_fops __ksym;
+
+const volatile enum bpf_obj_type obj_type = BPF_OBJ_UNKNOWN;
+
+static __always_inline __u32 get_obj_id(void *ent, enum bpf_obj_type type)
+{
+ switch (type) {
+ case BPF_OBJ_PROG:
+ return BPF_CORE_READ((struct bpf_prog *)ent, aux, id);
+ case BPF_OBJ_MAP:
+ return BPF_CORE_READ((struct bpf_map *)ent, id);
+ case BPF_OBJ_BTF:
+ return BPF_CORE_READ((struct btf *)ent, id);
+ case BPF_OBJ_LINK:
+ return BPF_CORE_READ((struct bpf_link *)ent, id);
+ default:
+ return 0;
+ }
+}
+
+/* could be used only with BPF_LINK_TYPE_PERF_EVENT links */
+static __u64 get_bpf_cookie(struct bpf_link *link)
+{
+ struct bpf_perf_link *perf_link;
+ struct perf_event *event;
+
+ perf_link = container_of(link, struct bpf_perf_link, link);
+ event = BPF_CORE_READ(perf_link, perf_file, private_data);
+ return BPF_CORE_READ(event, bpf_cookie);
+}
+
+SEC("iter/task_file")
+int iter(struct bpf_iter__task_file *ctx)
+{
+ struct file *file = ctx->file;
+ struct task_struct *task = ctx->task;
+ struct pid_iter_entry e;
+ const void *fops;
+
+ if (!file || !task)
+ return 0;
+
+ switch (obj_type) {
+ case BPF_OBJ_PROG:
+ fops = &bpf_prog_fops;
+ break;
+ case BPF_OBJ_MAP:
+ fops = &bpf_map_fops;
+ break;
+ case BPF_OBJ_BTF:
+ fops = &btf_fops;
+ break;
+ case BPF_OBJ_LINK:
+ fops = &bpf_link_fops;
+ break;
+ default:
+ return 0;
+ }
+
+ if (file->f_op != fops)
+ return 0;
+
+ __builtin_memset(&e, 0, sizeof(e));
+ e.pid = task->tgid;
+ e.id = get_obj_id(file->private_data, obj_type);
+
+ if (obj_type == BPF_OBJ_LINK) {
+ struct bpf_link *link = (struct bpf_link *) file->private_data;
+
+ if (BPF_CORE_READ(link, type) == BPF_LINK_TYPE_PERF_EVENT) {
+ e.has_bpf_cookie = true;
+ e.bpf_cookie = get_bpf_cookie(link);
+ }
+ }
+
+ bpf_probe_read_kernel_str(&e.comm, sizeof(e.comm),
+ task->group_leader->comm);
+ bpf_seq_write(ctx->meta->seq, &e, sizeof(e));
+
+ return 0;
+}
+
+char LICENSE[] SEC("license") = "Dual BSD/GPL";