diff options
| author | Eric Dumazet <edumazet@google.com> | 2024-03-29 15:42:21 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2024-04-01 11:28:32 +0100 |
| commit | a7ae7b0b2ea014ff3ed4be812c3efa1b1d86e153 (patch) | |
| tree | a3f559c1b1381749fa4e444f8ee14a050b74001d /include | |
| parent | 95e48d862ada73188be6d91a33c49d1712815bd2 (diff) | |
net: make softnet_data.dropped an atomic_t
If under extreme cpu backlog pressure enqueue_to_backlog() has
to drop a packet, it could do this without dirtying a cache line
and potentially slowing down the target cpu.
Move sd->dropped into a separate cache line, and make it atomic.
In non pressure mode, this field is not touched, no need to consume
valuable space in a hot cache line.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/netdevice.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 0cd9ee83f554..be9f071a340d 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3237,10 +3237,11 @@ struct softnet_data { unsigned int input_queue_tail; #endif unsigned int received_rps; - unsigned int dropped; struct sk_buff_head input_pkt_queue; struct napi_struct backlog; + atomic_t dropped ____cacheline_aligned_in_smp; + /* Another possibly contended cache line */ spinlock_t defer_lock ____cacheline_aligned_in_smp; int defer_count; |