From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56480) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yf8cZ-0003HZ-Fe for qemu-devel@nongnu.org; Mon, 06 Apr 2015 11:07:29 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Yf8cU-0006T5-EB for qemu-devel@nongnu.org; Mon, 06 Apr 2015 11:07:27 -0400 Received: from mx1.redhat.com ([209.132.183.28]:53054) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yf8cU-0006Sw-6X for qemu-devel@nongnu.org; Mon, 06 Apr 2015 11:07:22 -0400 Date: Mon, 6 Apr 2015 17:07:15 +0200 From: "Michael S. Tsirkin" Message-ID: <20150406164938-mutt-send-email-mst@redhat.com> References: <20150124121851.4278.77991.stgit@s440> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150124121851.4278.77991.stgit@s440> Subject: Re: [Qemu-devel] [PATCH v2] vhost-user: add multi queue support List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Nikolay Nikolaev Cc: snabb-devel@googlegroups.com, thomas.long@intel.com, qemu-devel@nongnu.org, tech@virtualopensystems.com On Sat, Jan 24, 2015 at 02:22:29PM +0200, Nikolay Nikolaev wrote: > Vhost-user will implement the multiqueueu support in a similar way to what multiqueue > vhost already has - a separate thread for each queue. > > To enable the multiqueue funcionality - a new command line parameter > "queues" is introduced for the vhost-user netdev. > > Changes since v1: > - use s->nc.info_str when bringing up/down the backend > > Signed-off-by: Nikolay Nikolaev > --- > docs/specs/vhost-user.txt | 5 +++++ > hw/virtio/vhost-user.c | 6 +++++- > net/vhost-user.c | 39 +++++++++++++++++++++++++-------------- > qapi-schema.json | 6 +++++- > qemu-options.hx | 5 +++-- > 5 files changed, 43 insertions(+), 18 deletions(-) > > diff --git a/docs/specs/vhost-user.txt b/docs/specs/vhost-user.txt > index 650bb18..d7b208c 100644 > --- a/docs/specs/vhost-user.txt > +++ b/docs/specs/vhost-user.txt I've been thinking that the protocol might be a useful addition to the virtio spec. For this, as a minimum you would have to submit this document as a comment to virtio TC with a proposal to include it in the virtio spec. See https://www.oasis-open.org/committees/comments/index.php?wg_abbrev=virtio Can you do this? We can take it from there, though I would encourage your company to join as a contributor. > @@ -127,6 +127,11 @@ in the ancillary data: > If Master is unable to send the full message or receives a wrong reply it will > close the connection. An optional reconnection mechanism can be implemented. > > +Multi queue suport > +--------------------- > +The protocol supports multiple queues by setting all index fields in the sent > +messages to a properly calculated value. > + Something that's not clear from this document is what happens with control VQ. Can you clarify please? > Message types > ------------- > > diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c > index aefe0bb..83ebcaa 100644 > --- a/hw/virtio/vhost-user.c > +++ b/hw/virtio/vhost-user.c > @@ -253,17 +253,20 @@ static int vhost_user_call(struct vhost_dev *dev, unsigned long int request, > case VHOST_SET_VRING_NUM: > case VHOST_SET_VRING_BASE: > memcpy(&msg.state, arg, sizeof(struct vhost_vring_state)); > + msg.state.index += dev->vq_index; > msg.size = sizeof(m.state); > break; > > case VHOST_GET_VRING_BASE: > memcpy(&msg.state, arg, sizeof(struct vhost_vring_state)); > + msg.state.index += dev->vq_index; > msg.size = sizeof(m.state); > need_reply = 1; > break; > > case VHOST_SET_VRING_ADDR: > memcpy(&msg.addr, arg, sizeof(struct vhost_vring_addr)); > + msg.addr.index += dev->vq_index; > msg.size = sizeof(m.addr); > break; > > @@ -271,7 +274,7 @@ static int vhost_user_call(struct vhost_dev *dev, unsigned long int request, > case VHOST_SET_VRING_CALL: > case VHOST_SET_VRING_ERR: > file = arg; > - msg.u64 = file->index & VHOST_USER_VRING_IDX_MASK; > + msg.u64 = (file->index + dev->vq_index) & VHOST_USER_VRING_IDX_MASK; > msg.size = sizeof(m.u64); > if (ioeventfd_enabled() && file->fd > 0) { > fds[fd_num++] = file->fd; > @@ -313,6 +316,7 @@ static int vhost_user_call(struct vhost_dev *dev, unsigned long int request, > error_report("Received bad msg size.\n"); > return -1; > } > + msg.state.index -= dev->vq_index; > memcpy(arg, &msg.state, sizeof(struct vhost_vring_state)); > break; > default: > diff --git a/net/vhost-user.c b/net/vhost-user.c > index 24e050c..a0b4af2 100644 > --- a/net/vhost-user.c > +++ b/net/vhost-user.c > @@ -122,37 +122,39 @@ static void net_vhost_user_event(void *opaque, int event) > case CHR_EVENT_OPENED: > vhost_user_start(s); > net_vhost_link_down(s, false); > - error_report("chardev \"%s\" went up\n", s->chr->label); > + error_report("chardev \"%s\" went up\n", s->nc.info_str); > break; > case CHR_EVENT_CLOSED: > net_vhost_link_down(s, true); > vhost_user_stop(s); > - error_report("chardev \"%s\" went down\n", s->chr->label); > + error_report("chardev \"%s\" went down\n", s->nc.info_str); > break; > } > } > > static int net_vhost_user_init(NetClientState *peer, const char *device, > const char *name, CharDriverState *chr, > - bool vhostforce) > + bool vhostforce, uint32_t queues) > { > NetClientState *nc; > VhostUserState *s; > + int i; > > - nc = qemu_new_net_client(&net_vhost_user_info, peer, device, name); > + for (i = 0; i < queues; i++) { > + nc = qemu_new_net_client(&net_vhost_user_info, peer, device, name); > > - snprintf(nc->info_str, sizeof(nc->info_str), "vhost-user to %s", > - chr->label); > + snprintf(nc->info_str, sizeof(nc->info_str), "vhost-user%d to %s", > + i, chr->label); > > - s = DO_UPCAST(VhostUserState, nc, nc); > + s = DO_UPCAST(VhostUserState, nc, nc); > > - /* We don't provide a receive callback */ > - s->nc.receive_disabled = 1; > - s->chr = chr; > - s->vhostforce = vhostforce; > - > - qemu_chr_add_handlers(s->chr, NULL, NULL, net_vhost_user_event, s); > + /* We don't provide a receive callback */ > + s->nc.receive_disabled = 1; > + s->chr = chr; > + s->vhostforce = vhostforce; > > + qemu_chr_add_handlers(s->chr, NULL, NULL, net_vhost_user_event, s); > + } > return 0; > } > > @@ -228,6 +230,7 @@ static int net_vhost_check_net(QemuOpts *opts, void *opaque) > int net_init_vhost_user(const NetClientOptions *opts, const char *name, > NetClientState *peer) > { > + uint32_t queues; > const NetdevVhostUserOptions *vhost_user_opts; > CharDriverState *chr; > bool vhostforce; > @@ -254,5 +257,13 @@ int net_init_vhost_user(const NetClientOptions *opts, const char *name, > vhostforce = false; > } > > - return net_vhost_user_init(peer, "vhost_user", name, chr, vhostforce); > + /* number of queues for multiqueue */ > + if (vhost_user_opts->has_queues) { > + queues = vhost_user_opts->queues; > + } else { > + queues = 1; > + } > + > + return net_vhost_user_init(peer, "vhost_user", name, chr, vhostforce, > + queues); > } > diff --git a/qapi-schema.json b/qapi-schema.json > index e16f8eb..c2cead0 100644 > --- a/qapi-schema.json > +++ b/qapi-schema.json > @@ -2287,12 +2287,16 @@ > # > # @vhostforce: #optional vhost on for non-MSIX virtio guests (default: false). > # > +# @queues: #optional number of queues to be created for multiqueue vhost-user > +# (Since 2.3) > +# > # Since 2.1 > ## > { 'type': 'NetdevVhostUserOptions', > 'data': { > 'chardev': 'str', > - '*vhostforce': 'bool' } } > + '*vhostforce': 'bool', > + '*queues': 'uint32' } } > > ## > # @NetClientOptions > diff --git a/qemu-options.hx b/qemu-options.hx > index 85ca3ad..b5fa61f 100644 > --- a/qemu-options.hx > +++ b/qemu-options.hx > @@ -1894,13 +1894,14 @@ The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single > netdev. @code{-net} and @code{-device} with parameter @option{vlan} create the > required hub automatically. > > -@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off] > +@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n] > > Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should > be a unix domain socket backed one. The vhost-user uses a specifically defined > protocol to pass vhost ioctl replacement messages to an application on the other > end of the socket. On non-MSIX guests, the feature can be forced with > -@var{vhostforce}. > +@var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to > +be created for multiqueue vhost-user. > > Example: > @example