From a7ae7b0b2ea014ff3ed4be812c3efa1b1d86e153 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 29 Mar 2024 15:42:21 +0000 Subject: 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 Signed-off-by: David S. Miller --- net/core/net-procfs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/core/net-procfs.c') diff --git a/net/core/net-procfs.c b/net/core/net-procfs.c index a97eceb84e61..fa6d3969734a 100644 --- a/net/core/net-procfs.c +++ b/net/core/net-procfs.c @@ -144,7 +144,8 @@ static int softnet_seq_show(struct seq_file *seq, void *v) seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x %08x %08x %08x %08x %08x " "%08x %08x\n", - sd->processed, sd->dropped, sd->time_squeeze, 0, + sd->processed, atomic_read(&sd->dropped), + sd->time_squeeze, 0, 0, 0, 0, 0, /* was fastroute */ 0, /* was cpu_collision */ sd->received_rps, flow_limit_count, -- cgit v1.2.3