packet: reorder a member in packet_ring_buffer
authorDaniel Borkmann <dborkman@redhat.com>
Fri, 19 Apr 2013 06:12:28 +0000 (06:12 +0000)
committerDavid S. Miller <davem@davemloft.net>
Thu, 25 Apr 2013 05:29:43 +0000 (01:29 -0400)
commit0578edc5604e3e192980f406f9e1040aa6434ca4
tree20d3f3cf7a9666235c20d541b3a3c4b938995200
parent660f7d22298ceb82facd2088c197f2de5cbfb7d6
packet: reorder a member in packet_ring_buffer

There's a 4 byte hole in packet_ring_buffer structure before
prb_bdqc, that can be filled with 'pending' member, thus we can
reduce the overall structure size from 224 bytes to 216 bytes.
This also has the side-effect, that in struct packet_sock 2*4 byte
holes after the embedded packet_ring_buffer members are removed,
and overall, packet_sock can be reduced by 1 cacheline:

Before: size: 1344, cachelines: 21, members: 24
After:  size: 1280, cachelines: 20, members: 24

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/packet/internal.h