From 909dc495f3b2f989a652022a78fbb5ef313a0652 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Mon, 9 May 2022 14:26:13 +0200 Subject: [PATCH] netfilter: flowtable: fix excessive hw offload attempts after failure If a flow cannot be offloaded, the code currently repeatedly tries again as quickly as possible, which can significantly increase system load. Fix this by limiting flow timeout update and hardware offload retry to once per second. Fixes: cad1732afa56 ("netfilter: flowtable: Remove redundant hw refresh bit") Signed-off-by: Felix Fietkau Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_flow_table_core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nf_flow_table_core.c b/net/netfilter/nf_flow_table_core.c index 3db256da919ba..20b4a14e5d4ea 100644 --- a/net/netfilter/nf_flow_table_core.c +++ b/net/netfilter/nf_flow_table_core.c @@ -335,8 +335,10 @@ void flow_offload_refresh(struct nf_flowtable *flow_table, u32 timeout; timeout = nf_flowtable_time_stamp + flow_offload_get_timeout(flow); - if (READ_ONCE(flow->timeout) != timeout) + if (timeout - READ_ONCE(flow->timeout) > HZ) WRITE_ONCE(flow->timeout, timeout); + else + return; if (likely(!nf_flowtable_hw_offload(flow_table))) return; -- 2.39.5