Jason Wang bc85ccfdf5 virtio-pci: use zero length mmio eventfd for 1.0 notification cap when possible ... We use data match eventfd for 1.0 notification currently. This could be slow since software decoding is needed for mmio exit. To speed this up, we can switch to use zero length mmio eventfd for 1.0 notification since we can examine the queue index directly from the writing address. KVM kernel module can utilize this by registering it to fast mmio bus which could be as fast as pio on ept capable machine when fast mmio is supported by host kernel. Lots of improvements were seen on a ept capable machine: Guest RX:(TCP) size/session/+throughput%/+cpu%/-+per cpu%/ 64/1/+1.6807%/[-16.2421%]/[+21.3984%]/ 64/2/+0.6091%/[-11.0187%]/[+13.0678%]/ 64/4/+0.0553%/[-5.9768%]/[+6.4155%]/ 64/8/+0.1206%/[-4.0057%]/[+4.2984%]/ 256/1/-0.0031%/[-10.1166%]/[+11.2517%]/ 256/2/-0.5058%/[-6.1656%]/+6.0317%]/ ... Guest TX:(TCP) size/session/+throughput%/+cpu%/-+per cpu%/ 64/1/[+18.9183%]/-0.2823%/[+19.2550%]/ 64/2/[+13.5714%]/[+2.2675%]/[+11.0533%]/ 64/4/[+13.1070%]/[+2.1817%]/[+10.6920%]/ 64/8/[+13.0426%]/[+2.0887%]/[+10.7299%]/ 256/1/[+36.2761%]/+6.3434%/[+28.1471%]/ ... 1024/1/[+44.8873%]/+2.0811%/[+41.9335%]/ ... 1024/4/+0.0228%/[-2.2044%]/[+2.2774%]/ ... 16384/2/+0.0127%/[-5.0346%]/[+5.3148%]/ ... 65535/1/[+0.0062%]/[-4.1183%]/[+4.3017%]/ 65535/2/+0.0004%/[-4.2311%]/[+4.4185%]/ 65535/4/+0.0107%/[-4.6106%]/[+4.8446%]/ 65535/8/-0.0090%/[-5.5178%]/[+5.8306%]/ Latency:(TCP_RR) size/session/+transaction rate%/+cpu%/-+per cpu%/ 64/1/[+6.5248%]/[-9.2882%]/[+17.4322%]/ 64/25/[+11.0854%]/[+0.8000%]/[+10.2038%]/ 64/50/[+12.1076%]/[+2.4627%]/[+9.4131%]/ 256/1/[+5.3677%]/[+10.5669%]/-4.7024%/ 256/25/[+5.6402%]/-0.8962%/[+6.5955%]/ 256/50/[+5.9685%]/[+1.7766%]/[+4.1188%]/ 4096/1/+0.2508%/[-10.4941%]/[+12.0047%]/ 4096/25/[+1.8533%]/-0.0273%/+1.8812%/ 4096/50/[+1.2156%]/-1.4134%/+2.6667%/ Notes: data with '[]' is the one whose significance is greater than 95%. Thanks Wenli Quan <wquan@redhat.com> for the benchmarking. Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>		2015-11-12 15:49:32 +02:00
..
dataplane	dataplane: support non-contigious s/g	2015-11-09 09:59:32 +00:00
Makefile.objs	dataplane: endianness-aware accesses	2015-02-16 15:07:16 +00:00
vhost-backend.c	vhost: use a function for each call	2015-10-22 14:34:49 +03:00
vhost-user.c	vhost-user: cleanup msg size math	2015-10-29 11:05:24 +02:00
vhost.c	vhost: set the correct queue index in case of migration with multiqueue	2015-10-22 14:34:50 +03:00
virtio-balloon.c	Inhibit ballooning during postcopy	2015-11-10 15:00:28 +01:00
virtio-bus.c	virtio: get_features() can fail	2015-07-27 18:11:53 +03:00
virtio-mmio.c	virtio: allow virtio-1 queue layout	2015-06-10 18:15:04 +02:00
virtio-pci.c	virtio-pci: use zero length mmio eventfd for 1.0 notification cap when possible	2015-11-12 15:49:32 +02:00
virtio-pci.h	virtio-pci: fix 1.0 virtqueue migration	2015-11-12 15:49:32 +02:00
virtio-rng.c	virtio: get_features() can fail	2015-07-27 18:11:53 +03:00
virtio.c	virtio-pci: fix 1.0 virtqueue migration	2015-11-12 15:49:32 +02:00