From 5f4197a020c049a59ea7907c31f9ab037dcefefe 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 [ Upstream commit 396ef64113a8ba01c46315d67a99db8dde3eef51 ] 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: c07531c01d82 ("netfilter: flowtable: Remove redundant hw refresh bit") Signed-off-by: Felix Fietkau Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- 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 b90eca7a2f22b..52e7f94d2450d 100644 --- a/net/netfilter/nf_flow_table_core.c +++ b/net/netfilter/nf_flow_table_core.c @@ -329,8 +329,10 @@ 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; -- 2.30.2