[RFC,3/4] bpf,cgroup,tracing: add new BPF_PROG_TYPE_CGROUP_TRACEPOINT

Commit Message

Ho, Kenny Nov. 18, 2021, 8:28 p.m. UTC

Change-Id: Ic9727186bb8c76c757e48635143b16e607f2299f
Signed-off-by: Kenny Ho <[e-mail]>
---
 include/linux/bpf-cgroup.h | 2 ++
 include/linux/bpf_types.h  | 4 ++++
 include/uapi/linux/bpf.h   | 2 ++
 kernel/bpf/syscall.c       | 4 ++++
 kernel/trace/bpf_trace.c   | 8 ++++++++
 5 files changed, 20 insertions(+)

Patch

diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h
index 2746fd804216..a5e4d9b19470 100644
--- a/include/linux/bpf-cgroup.h
+++ b/include/linux/bpf-cgroup.h
@@ -48,6 +48,7 @@  enum cgroup_bpf_attach_type {
 	CGROUP_INET4_GETSOCKNAME,
 	CGROUP_INET6_GETSOCKNAME,
 	CGROUP_INET_SOCK_RELEASE,
+	CGROUP_TRACEPOINT,
 	MAX_CGROUP_BPF_ATTACH_TYPE
 };
 
@@ -81,6 +82,7 @@  to_cgroup_bpf_attach_type(enum bpf_attach_type attach_type)
 	CGROUP_ATYPE(CGROUP_INET4_GETSOCKNAME);
 	CGROUP_ATYPE(CGROUP_INET6_GETSOCKNAME);
 	CGROUP_ATYPE(CGROUP_INET_SOCK_RELEASE);
+	CGROUP_ATYPE(CGROUP_TRACEPOINT);
 	default:
 		return CGROUP_BPF_ATTACH_TYPE_INVALID;
 	}
diff --git a/include/linux/bpf_types.h b/include/linux/bpf_types.h
index 9c81724e4b98..c108f498a35e 100644
--- a/include/linux/bpf_types.h
+++ b/include/linux/bpf_types.h
@@ -57,6 +57,10 @@  BPF_PROG_TYPE(BPF_PROG_TYPE_CGROUP_SYSCTL, cg_sysctl,
 BPF_PROG_TYPE(BPF_PROG_TYPE_CGROUP_SOCKOPT, cg_sockopt,
 	      struct bpf_sockopt, struct bpf_sockopt_kern)
 #endif
+#if defined (CONFIG_BPF_EVENTS) && defined (CONFIG_CGROUP_BPF)
+BPF_PROG_TYPE(BPF_PROG_TYPE_CGROUP_TRACEPOINT, cg_tracepoint,
+	      __u64, u64)
+#endif
 #ifdef CONFIG_BPF_LIRC_MODE2
 BPF_PROG_TYPE(BPF_PROG_TYPE_LIRC_MODE2, lirc_mode2,
 	      __u32, u32)
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 6fc59d61937a..014ffaa3fc2a 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -949,6 +949,7 @@  enum bpf_prog_type {
 	BPF_PROG_TYPE_LSM,
 	BPF_PROG_TYPE_SK_LOOKUP,
 	BPF_PROG_TYPE_SYSCALL, /* a program that can execute syscalls */
+	BPF_PROG_TYPE_CGROUP_TRACEPOINT,
 };
 
 enum bpf_attach_type {
@@ -994,6 +995,7 @@  enum bpf_attach_type {
 	BPF_SK_REUSEPORT_SELECT,
 	BPF_SK_REUSEPORT_SELECT_OR_MIGRATE,
 	BPF_PERF_EVENT,
+	BPF_CGROUP_TRACEPOINT,
 	__MAX_BPF_ATTACH_TYPE
 };
 
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 4e50c0bfdb7d..d77598fa4eb2 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -2149,6 +2149,7 @@  static bool is_perfmon_prog_type(enum bpf_prog_type prog_type)
 	case BPF_PROG_TYPE_LSM:
 	case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */
 	case BPF_PROG_TYPE_EXT: /* extends any prog */
+	case BPF_PROG_TYPE_CGROUP_TRACEPOINT:
 		return true;
 	default:
 		return false;
@@ -3137,6 +3138,8 @@  attach_type_to_prog_type(enum bpf_attach_type attach_type)
 		return BPF_PROG_TYPE_SK_LOOKUP;
 	case BPF_XDP:
 		return BPF_PROG_TYPE_XDP;
+	case BPF_CGROUP_TRACEPOINT:
+		return BPF_PROG_TYPE_CGROUP_TRACEPOINT;
 	default:
 		return BPF_PROG_TYPE_UNSPEC;
 	}
@@ -3189,6 +3192,7 @@  static int bpf_prog_attach(const union bpf_attr *attr)
 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
+	case BPF_PROG_TYPE_CGROUP_TRACEPOINT:
 	case BPF_PROG_TYPE_SOCK_OPS:
 		ret = cgroup_bpf_prog_attach(attr, ptype, prog);
 		break;
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 8addd10202c2..4ad864a4852a 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1798,6 +1798,14 @@  const struct bpf_verifier_ops perf_event_verifier_ops = {
 const struct bpf_prog_ops perf_event_prog_ops = {
 };
 
+const struct bpf_verifier_ops cg_tracepoint_verifier_ops = {
+	.get_func_proto  = tp_prog_func_proto,
+	.is_valid_access = tp_prog_is_valid_access,
+};
+
+const struct bpf_prog_ops cg_tracepoint_prog_ops = {
+};
+
 static DEFINE_MUTEX(bpf_event_mutex);
 
 #define BPF_TRACE_MAX_PROGS 64