virtio: batch transmitted packets
virtio: batch transmitted packets

Instead of placing packets directly into the virtio ring, add them to
a temporary queue, and flush it when we are polled.  This reduces
cross-cpu writes and kicks.

avikivity/seastar,acbellini/seastar,tempbottle/seastar,tempbottle/scylla,asias/scylla,asias/scylla,dwdm/seastar,slivne/seastar,bowlofstew/scylla,joerg84/seastar,dreamsxin/seastar,rluta/scylla,rentongzhang/scylla,cloudius-systems/seastar,norcimo5/seastar,scylladb/scylla-seastar,wildinto/scylla,raphaelsc/seastar,jonathanleang/seastar,phonkee/scylla,kjniemi/seastar,hongliangzhao/seastar,kjniemi/scylla,printedheart/seastar,anzihenry/seastar,koolhazz/seastar,scylladb/scylla,rluta/scylla,raphaelsc/seastar,acbellini/scylla,avikivity/scylla,aruanruan/scylla,justintung/scylla,glommer/scylla,eklitzke/scylla,acbellini/scylla,dwdm/seastar,shaunstanislaus/scylla,flashbuckets/seastar,shaunstanislaus/scylla,avikivity/scylla,wildinto/scylla,ducthangho/imdb,slivne/seastar,victorbriz/scylla,capturePointer/scylla,tempbottle/scylla,linearregression/scylla,joerg84/seastar,leejir/seastar,koolhazz/seastar,shaunstanislaus/scylla,stamhe/seastar,raphaelsc/scylla,flashbuckets/seastar,dwdm/scylla,guiquanz/scylla,mixja/seastar,dreamsxin/seastar,syuu1228/seastar,scylladb/scylla,gwicke/scylla,raphaelsc/seastar,rentongzhang/scylla,linearregression/seastar,flashbuckets/seastar,kjniemi/scylla,asias/scylla,avikivity/seastar,bzero/seastar,acbellini/scylla,norcimo5/seastar,raphaelsc/scylla,scylladb/scylla,senseb/scylla,respu/scylla,gwicke/scylla,duarten/scylla,dwdm/scylla,scylladb/seastar,scylladb/scylla-seastar,shyamalschandra/seastar,linearregression/scylla,leejir/seastar,respu/scylla,slivne/seastar,xtao/seastar,sjperkins/seastar,phonkee/scylla,kjniemi/scylla,raphaelsc/scylla,tempbottle/scylla,ducthangho/imdb,scylladb/scylla-seastar,cloudius-systems/seastar,bowlofstew/seastar,kangkot/scylla,hongliangzhao/seastar,chunshengster/seastar,duarten/scylla,tempbottle/seastar,sjperkins/seastar,stamhe/scylla,guiquanz/scylla,stamhe/seastar,justintung/scylla,justintung/scylla,printedheart/seastar,chunshengster/seastar,dwdm/scylla,acbellini/seastar,rentongzhang/scylla,scylladb/seastar,rluta/scylla,kangkot/scylla,anzihenry/seastar,wildinto/scylla,shyamalschandra/seastar,phonkee/scylla,syuu1228/seastar,xtao/seastar,kangkot/scylla,wildinto/seastar,stamhe/seastar,mixja/seastar,wildinto/seastar,sjperkins/seastar,dreamsxin/seastar,duarten/scylla,stamhe/scylla,linearregression/seastar,avikivity/scylla,tempbottle/seastar,jonathanleang/seastar,ducthangho/imdb,guiquanz/scylla,mixja/seastar,norcimo5/seastar,bowlofstew/scylla,victorbriz/scylla,capturePointer/scylla,linearregression/seastar,cloudius-systems/seastar,kjniemi/seastar,koolhazz/seastar,eklitzke/scylla,respu/scylla,stamhe/scylla,kjniemi/seastar,jonathanleang/seastar,bzero/seastar,syuu1228/seastar,joerg84/seastar,victorbriz/scylla,anzihenry/seastar,dwdm/seastar,gwicke/scylla,avikivity/seastar,leejir/seastar,capturePointer/scylla,shyamalschandra/seastar,aruanruan/scylla,glommer/scylla,senseb/scylla,eklitzke/scylla,scylladb/seastar,xtao/seastar,aruanruan/scylla,bzero/seastar,glommer/scylla,scylladb/scylla,bowlofstew/seastar,senseb/scylla,wildinto/seastar,hongliangzhao/seastar,printedheart/seastar,bowlofstew/scylla,acbellini/seastar,bowlofstew/seastar,linearregression/scylla,chunshengster/seastar