On 01/07/15 at 09:32am, Alexei Starovoitov wrote:
> I'm afraid 'union' style with first u8 flags working as selector
> won't work for the case you're describing, but since
> md.gbp = ntohs(vxh->gbp.policy_id);
> 2652: 41 0f b7 55 0a movzwl 0xa(%r13),%edx
> then at least from performance side it's ok at least on x86.
> So this _packed stuff is fine, though not pretty.
> It's internal header, so we can improve it later.
I'm not sure I understand your first sentence but I'm not
married to the code as-is.
Would you like something like this?
struct vxlanhdr_gbp {
__u8 vx_flags;
+#ifdef __LITTLE_ENDIAN_BITFIELD
+ __u8 reserved_flags1:3,
+ policy_applied:1,
+ reserved_flags2:2,
+ dont_learn:1,
+ reserved_flags3:1;
+#elif defined(__BIG_ENDIAN_BITFIELD)
+ __u8 reserved_flags1:1,
+ dont_learn:1,
+ reserved_flags2:2,
+ policy_applied:1,
+ reserved_flags3:3;
+#else
+#error "Please fix <asm/byteorder.h>"
+#endif
+ __be16 policy_id;
+ __be32 vx_vni;
};
struct vxlanhdr {
+ union {
+ struct {
+#ifdef __LITTLE_ENDIAN_BITFIELD
+ __u8 reserved_flags1:3,
+ vni_present:1,
+ reserved_flags2:3,
+ gbp_present:1;
+#elif defined(__BIG_ENDIAN_BITFIELD)
+ __u8 gbp_present:1,
+ reserved_flags2:3,
+ vni_present:1,
+ reserved_flags1:3;
+#else
+#error "Please fix <asm/byteorder.h>"
+#endif
+ __u8 vx_reserved1;
+ __be16 vx_reserved2;
+ };
+ __be32 vx_flags;
+ };
+ __be32 vx_vni;
};
_______________________________________________
dev mailing list
dev@openvswitch.org
http://openvswitch.org/mailman/listinfo/dev
