On 12/7/18 3:20 PM, Eric Dumazet wrote:
>
>
> On 12/07/2018 01:49 PM, David Ahern wrote:
>> From: David Ahern <dsah...@gmail.com>
>>
>> Similar to routes and rules, add protocol attribute to neighbor entries
>> for easier tracking of how each was created.
>>
>> Signed-off-by: David Ahern <dsah...@gmail.com>
>> ---
>> include/net/neighbour.h | 2 ++
>> include/uapi/linux/neighbour.h | 1 +
>> net/core/neighbour.c | 24 +++++++++++++++++++++++-
>> 3 files changed, 26 insertions(+), 1 deletion(-)
>>
>> diff --git a/include/net/neighbour.h b/include/net/neighbour.h
>> index 6c13072910ab..e93c59df9501 100644
>> --- a/include/net/neighbour.h
>> +++ b/include/net/neighbour.h
>> @@ -149,6 +149,7 @@ struct neighbour {
>> __u8 nud_state;
>> __u8 type;
>> __u8 dead;
>> + u8 protocol;
>> seqlock_t ha_lock;
>> unsigned char ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))];
>
> This looks like ha[] alignment would change, I am not sure how critical it is.
Just adds 4 bytes to neighbour:
...
/* --- cacheline 2 boundary (128 bytes) --- */
long unsigned int used; /* 128 8 */
atomic_t probes; /* 136 4 */
__u8 flags; /* 140 1 */
__u8 nud_state; /* 141 1 */
__u8 type; /* 142 1 */
__u8 dead; /* 143 1 */
u8 protocol; /* 144 1 */
/* XXX 3 bytes hole, try to pack */
seqlock_t ha_lock; /* 148 8 */
unsigned char ha[32]; /* 156 32 */
/* XXX 4 bytes hole, try to pack */
/* --- cacheline 3 boundary (192 bytes) --- */
struct hh_cache hh; /* 192 48 */
...
but does not change the actual allocation size which is rounded to 512.
