On Tue, Apr 26, 2022 at 09:28:13PM +0900, Ritaro Takenaka wrote: > Thanks for your reply. > > > In 5.4, this check is only enabled for xfrm. > Packet loss occurs with xmit (xfrm is not confirmed). > I also experienced packet loss with 5.10, which runs dst_check periodically. > Route GC and flowtable GC are not synchronized, so it is > necessary to check each packet. > > > dst_check() should deal with this. > When dst_check is used, the performance degradation is not negligible. > From 900 Mbps to 700 Mbps with QCA9563 simple firewall. You mention 5.10 above. Starting 5.12, dst_check() uses INDIRECT_CALL_INET. Is dst_check() still slow with >= 5.12? Asking this because my understanding (at this stage) is that this check for blackhole_netdev is a faster way to check for stale cached routes.
