path: root/net/packet/internal.h
diff options
authorDaniel Borkmann <dborkman@redhat.com>2013-04-19 06:12:28 +0000
committerDavid S. Miller <davem@davemloft.net>2013-04-25 01:29:43 -0400
commit0578edc5604e3e192980f406f9e1040aa6434ca4 (patch)
tree20d3f3cf7a9666235c20d541b3a3c4b938995200 /net/packet/internal.h
parent660f7d22298ceb82facd2088c197f2de5cbfb7d6 (diff)
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>
Diffstat (limited to 'net/packet/internal.h')
1 files changed, 3 insertions, 1 deletions
diff --git a/net/packet/internal.h b/net/packet/internal.h
index e891f025a1b..650751b9a7e 100644
--- a/net/packet/internal.h
+++ b/net/packet/internal.h
@@ -54,6 +54,7 @@ struct pgv {
struct packet_ring_buffer {
struct pgv *pg_vec;
unsigned int head;
unsigned int frames_per_block;
unsigned int frame_size;
@@ -63,8 +64,9 @@ struct packet_ring_buffer {
unsigned int pg_vec_pages;
unsigned int pg_vec_len;
- struct tpacket_kbdq_core prb_bdqc;
atomic_t pending;
+ struct tpacket_kbdq_core prb_bdqc;
extern struct mutex fanout_mutex;