Generate bpf_kern.o at build time

Use bpf module type to compile bpf_kern.c into bpf_kern.o at build
time.

Bug: 72981744
Test: m
Change-Id: I2d5018541f31ef328e8c78fe2fc90b2d34d69511
Merged-In: I2d5018541f31ef328e8c78fe2fc90b2d34d69511
(cherry picked from commit 883a24655723f237029297ec527c1ef4da4f232b)

4 files changed, 10 insertions, 13 deletions

diff --git a/bpfloader/Android.bp b/bpfloader/Android.bp
index 46b8a1f0..846264cf 100644
--- a/bpfloader/Android.bp
+++ b/bpfloader/Android.bp
@@ -45,3 +45,13 @@ cc_binary {
     ],
 
 }
+
+bpf {
+    name: "bpf_kern.o",
+    srcs: ["bpf_kern.c"],
+    cflags: [
+        "-Wall",
+        "-Werror",
+    ],
+    include_dirs: ["system/netd/libbpf/include"],
+}
diff --git a/bpfloader/Android.mk b/bpfloader/Android.mk
deleted file mode 100644
index 13933767..00000000
--- a/bpfloader/Android.mk
+++ /dev/null
@@ -1,12 +0,0 @@
-LOCAL_PATH:= $(call my-dir)
-
-#######################################
-# bpf_kern.o
-include $(CLEAR_VARS)
-
-LOCAL_MODULE := bpf_kern.o
-LOCAL_SRC_FILES := $(LOCAL_MODULE)
-LOCAL_MODULE_CLASS := ETC
-LOCAL_MODULE_PATH := $(TARGET_OUT_ETC)/bpf
-
-include $(BUILD_PREBUILT)
diff --git a/bpfloader/bpf_kern.h b/bpfloader/bpf_kern.h
index 975f4655..69803e87 100644
--- a/bpfloader/bpf_kern.h
+++ b/bpfloader/bpf_kern.h
@@ -175,7 +175,6 @@ static __always_inline inline int bpf_traffic_account(struct __sk_buff* skb, int
     counterSet = find_map_entry(UID_COUNTERSET_MAP, &uid);
     if (counterSet) key.counterSet = *counterSet;
 
-    int ret;
     if (tag) {
         bpf_update_stats(skb, TAG_STATS_MAP, direction, &key);
     }
diff --git a/bpfloader/bpf_kern.o b/bpfloader/bpf_kern.o
deleted file mode 100644
index 7b60514e..00000000
--- a/bpfloader/bpf_kern.o
+++ /dev/null