The patch below is base on https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/drivers/vhost/vhost.c?id=refs/tags/next-20130517 Signed-off-by: Chuanyu Qin <qinchuanyu@xxxxxxxxxx> --- a/drivers/vhost/vhost.c 2013-05-20 11:47:05.000000000 +0800 +++ b/drivers/vhost/vhost.c 2013-05-20 11:48:24.000000000 +0800 @@ -154,9 +154,10 @@ if (list_empty(&work->node)) { list_add_tail(&work->node, &dev->work_list); work->queue_seq++; + spin_unlock_irqrestore(&dev->work_lock, flags); wake_up_process(dev->worker); - } - spin_unlock_irqrestore(&dev->work_lock, flags); + } else + spin_unlock_irqrestore(&dev->work_lock, flags); } void vhost_poll_queue(struct vhost_poll *poll) I did the test by using iperf in 10G environment, the test num as below: orignal modified thread_num tp(Gbps) vhost(%) | tp(Gbps) vhost(%) 1 9.59 28.82 | 9.59 27.49 8 9.61 32.92 | 9.62 26.77 64 9.58 46.48 | 9.55 38.99 256 9.6 63.7 | 9.6 52.59 The cost of vhost reduced while the throughput is almost unchanged. On 05/20/2013 11:06 AM, Qinchuanyu wrote: > Right now the wake_up_process func is included in spin_lock/unlock, but it could be done outside the spin_lock. > I have test it with kernel 3.0.27 and guest suse11-sp2, it provide 2%-3% net performance improved. > > Signed-off-by: Chuanyu Qin <qinchuanyu@xxxxxxxxxx> Make sense to me but need generate a patch against net-next.git or vhost.git in git.kernel.org. Btw. How did you test this? Care to share the perf numbers? Thanks > mu > --- a/drivers/vhost/vhost.c 2013-05-20 10:36:30.000000000 +0800 > +++ b/drivers/vhost/vhost.c 2013-05-20 10:36:54.000000000 +0800 > @@ -144,9 +144,10 @@ > if (list_empty(&work->node)) { > list_add_tail(&work->node, &dev->work_list); > work->queue_seq++; > + spin_unlock_irqrestore(&dev->work_lock, flags); > wake_up_process(dev->worker); > - } > - spin_unlock_irqrestore(&dev->work_lock, flags); > + } else > + spin_unlock_irqrestore(&dev->work_lock, flags); > } > > void vhost_poll_queue(struct vhost_poll *poll) > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html ��.n��������+%������w��{.n�����o�^n�r������&��z�ޗ�zf���h���~����������_��+v���)ߣ�
