bpf: sock_ops: Change some members of sock_ops_kern from u32 to u8

A later patch needs to add a few pointers and a few u8 to
sock_ops_kern.  Hence, this patch saves some spaces by moving
some of the existing members from u32 to u8 so that the later
patch can still fit everything in a cacheline.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200820190058.2885640-1-kafai@fb.com
This commit is contained in:
Martin KaFai Lau 2020-08-20 12:00:58 -07:00 committed by Alexei Starovoitov
parent 331fca4315
commit c9985d09e1
2 changed files with 12 additions and 7 deletions

View File

@ -1236,13 +1236,13 @@ struct bpf_sock_addr_kern {
struct bpf_sock_ops_kern {
struct sock *sk;
u32 op;
union {
u32 args[4];
u32 reply;
u32 replylong[4];
};
u32 is_fullsock;
u8 op;
u8 is_fullsock;
u64 temp; /* temp and everything after is not
* initialized to 0 before calling
* the BPF program. New fields that

View File

@ -8465,17 +8465,22 @@ static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
return insn - insn_buf;
switch (si->off) {
case offsetof(struct bpf_sock_ops, op) ...
case offsetof(struct bpf_sock_ops, op):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
op),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, op));
break;
case offsetof(struct bpf_sock_ops, replylong[0]) ...
offsetof(struct bpf_sock_ops, replylong[3]):
BUILD_BUG_ON(sizeof_field(struct bpf_sock_ops, op) !=
sizeof_field(struct bpf_sock_ops_kern, op));
BUILD_BUG_ON(sizeof_field(struct bpf_sock_ops, reply) !=
sizeof_field(struct bpf_sock_ops_kern, reply));
BUILD_BUG_ON(sizeof_field(struct bpf_sock_ops, replylong) !=
sizeof_field(struct bpf_sock_ops_kern, replylong));
off = si->off;
off -= offsetof(struct bpf_sock_ops, op);
off += offsetof(struct bpf_sock_ops_kern, op);
off -= offsetof(struct bpf_sock_ops, replylong[0]);
off += offsetof(struct bpf_sock_ops_kern, replylong[0]);
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
off);