Alexander Lobakin <aleksander.lobakin@xxxxxxxxx> writes: > Now that cpumap uses GRO, which drops unused skb heads to the NAPI > cache, use napi_skb_cache_get_bulk() to try to reuse cached entries > and lower MM layer pressure. Always disable the BH before checking and > running the cpumap-pinned XDP prog and don't re-enable it in between > that and allocating an skb bulk, as we can access the NAPI caches only > from the BH context. > The better GRO aggregates packets, the less new skbs will be allocated. > If an aggregated skb contains 16 frags, this means 15 skbs were returned > to the cache, so next 15 skbs will be built without allocating anything. > > The same trafficgen UDP GRO test now shows: > > GRO off GRO on > threaded GRO 2.3 4 Mpps > thr bulk GRO 2.4 4.7 Mpps > diff +4 +17 % > > Comparing to the baseline cpumap: > > baseline 2.7 N/A Mpps > thr bulk GRO 2.4 4.7 Mpps > diff -11 +74 % > > Signed-off-by: Alexander Lobakin <aleksander.lobakin@xxxxxxxxx> > Tested-by: Daniel Xu <dxu@xxxxxxxxx> Reviewed-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx>
