lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Thu, 10 Aug 2017 18:46:05 +0200 From: Paolo Bonzini <pbonzini@...hat.com> To: "Richard W.M. Jones" <rjones@...hat.com>, jejb@...ux.vnet.ibm.com Cc: martin.petersen@...cle.com, mst@...hat.com, jasowang@...hat.com, linux-scsi@...r.kernel.org, linux-kernel@...r.kernel.org, virtualization@...ts.linux-foundation.org, hch@....de Subject: Re: [PATCH 2/2] virtio: virtio_scsi: Set can_queue to the length of the virtqueue. On 10/08/2017 18:40, Richard W.M. Jones wrote: > Since switching to blk-mq as the default in commit 5c279bd9e406 > ("scsi: default to scsi-mq"), virtio-scsi LUNs consume about 10x as > much kernel memory. > > qemu currently allocates a fixed 128 entry virtqueue. can_queue > currently is set to 1024. But with indirect descriptors, each command > in the queue takes 1 virtqueue entry, so the number of commands which > can be queued is equal to the length of the virtqueue. > > Note I intend to send a patch to qemu to allow the virtqueue size to > be configured from the qemu command line. You can clear .can_queue from the templates. Otherwise looks good. Paolo > Thanks Paolo Bonzini, Christoph Hellwig. > > Signed-off-by: Richard W.M. Jones <rjones@...hat.com> > --- > drivers/scsi/virtio_scsi.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c > index 9be211d68b15..d6b4ff634c0d 100644 > --- a/drivers/scsi/virtio_scsi.c > +++ b/drivers/scsi/virtio_scsi.c > @@ -972,6 +972,8 @@ static int virtscsi_probe(struct virtio_device *vdev) > if (err) > goto virtscsi_init_failed; > > + shost->can_queue = virtqueue_get_vring_size(vscsi->req_vqs[0].vq); > + > cmd_per_lun = virtscsi_config_get(vdev, cmd_per_lun) ?: 1; > shost->cmd_per_lun = min_t(u32, cmd_per_lun, shost->can_queue); > shost->max_sectors = virtscsi_config_get(vdev, max_sectors) ?: 0xFFFF; >
Powered by blists - more mailing lists