openvswitch: Compact sw_flow_key.
Minimize padding in sw_flow_key and move 'tp' top the main struct. These changes simplify code when accessing the transport port numbers and the tcp flags, and makes the sw_flow_key 8 bytes smaller on 64-bit systems (128->120 bytes). These changes also make the keys for IPv4 packets to fit in one cache line. There is a valid concern for safety of packing the struct ovs_key_ipv4_tunnel, as it would be possible to take the address of the tun_id member as a __be64 * which could result in unaligned access in some systems. However: - sw_flow_key itself is 64-bit aligned, so the tun_id within is always 64-bit aligned. - We never make arrays of ovs_key_ipv4_tunnel (which would force every second tun_key to be misaligned). - We never take the address of the tun_id in to a __be64 *. - Whereever we use struct ovs_key_ipv4_tunnel outside the sw_flow_key, it is in stack (on tunnel input functions), where compiler has full control of the alignment. Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com> Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
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