From 15ea59a0e9bf0dce546b6fcab5b00af8b35b870d Mon Sep 17 00:00:00 2001 From: Eddy Tao Date: Sun, 5 Feb 2023 09:35:37 +0800 Subject: net: openvswitch: reduce cpu_used_mask memory Use actual CPU number instead of hardcoded value to decide the size of 'cpu_used_mask' in 'struct sw_flow'. Below is the reason. 'struct cpumask cpu_used_mask' is embedded in struct sw_flow. Its size is hardcoded to CONFIG_NR_CPUS bits, which can be 8192 by default, it costs memory and slows down ovs_flow_alloc. To address this: Redefine cpu_used_mask to pointer. Append cpumask_size() bytes after 'stat' to hold cpumask. Initialization cpu_used_mask right after stats_last_writer. APIs like cpumask_next and cpumask_set_cpu never access bits beyond cpu count, cpumask_size() bytes of memory is enough. Signed-off-by: Eddy Tao Acked-by: Eelco Chaudron Link: https://lore.kernel.org/r/OS3P286MB229570CCED618B20355D227AF5D59@OS3P286MB2295.JPNP286.PROD.OUTLOOK.COM Signed-off-by: Jakub Kicinski --- net/openvswitch/flow.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/openvswitch/flow.h') diff --git a/net/openvswitch/flow.h b/net/openvswitch/flow.h index 073ab73ffeaa..b5711aff6e76 100644 --- a/net/openvswitch/flow.h +++ b/net/openvswitch/flow.h @@ -229,7 +229,7 @@ struct sw_flow { */ struct sw_flow_key key; struct sw_flow_id id; - struct cpumask cpu_used_mask; + struct cpumask *cpu_used_mask; struct sw_flow_mask *mask; struct sw_flow_actions __rcu *sf_acts; struct sw_flow_stats __rcu *stats[]; /* One for each CPU. First one -- cgit v1.2.3