ebpf: align fault_val to 8 bytes both sides (BTF warning fix)

Author: Twyx22

packaging/arch/PKGBUILD

@@ -15,7 +15,9 @@ provides=('memflux')
 conflicts=('memflux-git')
 backup=('etc/memflux.conf')
 source=("$pkgname-$pkgver.tar.gz::$url/archive/refs/tags/v$pkgver.tar.gz")
-sha256sums=('cc23c26143e62f24913ec0853ed1fee2e80abbcc7e0abe7075c80b4d3b67e7cd')
+# NOTE: GitHub release tarballs embed mtimes and are not byte-reproducible;
+# update this checksum on each version bump (makepkg prints the mismatch).
+sha256sums=('6938b43616ec5e451d2544c31493def3b7df0e6e4f9c6b587bbf85f859f30d92')
 install=memflux.install
 
 prepare() {

src/kern/ebpf.cpp

@@ -66,7 +66,7 @@ void unload(){
 bool loaded(){ return g.obj != nullptr; }
 
 struct fault_key { __u32 pid; };
-struct fault_val { __u64 minor; __u32 pad; };
+struct fault_val { __u64 minor; };
 
 std::map<pid_t, uint64_t> drain_faults(){
   std::map<pid_t, uint64_t> out;

src/kern/ebpf_access.bpf.c

@@ -13,7 +13,6 @@ struct fault_key { __u32 pid; };
 
 struct fault_val {
   __u64 minor;       // minor faults (page Fault sur address)
-  __u32 pad;
 };
 
 struct {