| Message ID | 20170628190047.26159-27-dgilbert@redhat.com |
|---|---|
| State | New |
| Headers | show |
On 06/28/2017 09:00 PM, Dr. David Alan Gilbert (git) wrote: > From: "Dr. David Alan Gilbert" <dgilbert@redhat.com> > > This message is sent just before the end of postcopy to get the > client to stop using userfault since we wont respond to any more > requests. It should close userfaultfd so that any other pages > get mapped to the backing file automatically by the kernel, since > at this point we know we've received everything. > > Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> > --- > contrib/libvhost-user/libvhost-user.c | 23 +++++++++++++++++++++++ > contrib/libvhost-user/libvhost-user.h | 1 + > hw/virtio/vhost-user.c | 1 + > 3 files changed, 25 insertions(+) > > diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c > index d37052b7b0..c1716d1a62 100644 > --- a/contrib/libvhost-user/libvhost-user.c > +++ b/contrib/libvhost-user/libvhost-user.c > @@ -68,6 +68,7 @@ vu_request_to_string(int req) > REQ(VHOST_USER_INPUT_GET_CONFIG), > REQ(VHOST_USER_POSTCOPY_ADVISE), > REQ(VHOST_USER_POSTCOPY_LISTEN), > + REQ(VHOST_USER_POSTCOPY_END), > REQ(VHOST_USER_MAX), > }; > #undef REQ > @@ -889,6 +890,26 @@ vu_set_postcopy_listen(VuDev *dev, VhostUserMsg *vmsg) > > return false; > } > + > +static bool > +vu_set_postcopy_end(VuDev *dev, VhostUserMsg *vmsg) > +{ > + fprintf(stderr, "%s: Entry\n", __func__); > + dev->postcopy_listening = false; > + if (dev->postcopy_ufd > 0) { > + close(dev->postcopy_ufd); > + dev->postcopy_ufd = -1; > + fprintf(stderr, "%s: Done close\n", __func__); > + } > + > + vmsg->fd_num = 0; > + vmsg->payload.u64 = 0; > + vmsg->size = sizeof(vmsg->payload.u64); > + vmsg->flags = VHOST_USER_VERSION | VHOST_USER_REPLY_MASK; > + fprintf(stderr, "%s: exit\n", __func__); > + return true; > +} > + It is what reply-ack is done for, so to avoid code duplication, maybe Qemu could set VHOST_USER_NEED_REPLY_MASK bit when reply-ack feature is supported. I'm wondering if we shouldn't consider adding reply-ack feature support to libvhost-user, and make postcopy support to depend on this feature. Cheers, Maxime
* Maxime Coquelin (maxime.coquelin@redhat.com) wrote: > > > On 06/28/2017 09:00 PM, Dr. David Alan Gilbert (git) wrote: > > From: "Dr. David Alan Gilbert" <dgilbert@redhat.com> > > > > This message is sent just before the end of postcopy to get the > > client to stop using userfault since we wont respond to any more > > requests. It should close userfaultfd so that any other pages > > get mapped to the backing file automatically by the kernel, since > > at this point we know we've received everything. > > > > Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> > > --- > > contrib/libvhost-user/libvhost-user.c | 23 +++++++++++++++++++++++ > > contrib/libvhost-user/libvhost-user.h | 1 + > > hw/virtio/vhost-user.c | 1 + > > 3 files changed, 25 insertions(+) > > > > diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c > > index d37052b7b0..c1716d1a62 100644 > > --- a/contrib/libvhost-user/libvhost-user.c > > +++ b/contrib/libvhost-user/libvhost-user.c > > @@ -68,6 +68,7 @@ vu_request_to_string(int req) > > REQ(VHOST_USER_INPUT_GET_CONFIG), > > REQ(VHOST_USER_POSTCOPY_ADVISE), > > REQ(VHOST_USER_POSTCOPY_LISTEN), > > + REQ(VHOST_USER_POSTCOPY_END), > > REQ(VHOST_USER_MAX), > > }; > > #undef REQ > > @@ -889,6 +890,26 @@ vu_set_postcopy_listen(VuDev *dev, VhostUserMsg *vmsg) > > return false; > > } > > + > > +static bool > > +vu_set_postcopy_end(VuDev *dev, VhostUserMsg *vmsg) > > +{ > > + fprintf(stderr, "%s: Entry\n", __func__); > > + dev->postcopy_listening = false; > > + if (dev->postcopy_ufd > 0) { > > + close(dev->postcopy_ufd); > > + dev->postcopy_ufd = -1; > > + fprintf(stderr, "%s: Done close\n", __func__); > > + } > > + > > + vmsg->fd_num = 0; > > + vmsg->payload.u64 = 0; > > + vmsg->size = sizeof(vmsg->payload.u64); > > + vmsg->flags = VHOST_USER_VERSION | VHOST_USER_REPLY_MASK; > > + fprintf(stderr, "%s: exit\n", __func__); > > + return true; > > +} > > + > > It is what reply-ack is done for, so to avoid code duplication, > maybe Qemu could set VHOST_USER_NEED_REPLY_MASK bit when reply-ack > feature is supported. > > I'm wondering if we shouldn't consider adding reply-ack feature support > to libvhost-user, and make postcopy support to depend on this feature. Yes, that would make sense; for the moment I'm adding what I think is the same replies in the places I need ack's, and setting the VHOST_USER_NEED_REPLY_MASK so for the messages where I need it the semantics should be the same as that. Dave > Cheers, > Maxime -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c index d37052b7b0..c1716d1a62 100644 --- a/contrib/libvhost-user/libvhost-user.c +++ b/contrib/libvhost-user/libvhost-user.c @@ -68,6 +68,7 @@ vu_request_to_string(int req) REQ(VHOST_USER_INPUT_GET_CONFIG), REQ(VHOST_USER_POSTCOPY_ADVISE), REQ(VHOST_USER_POSTCOPY_LISTEN), + REQ(VHOST_USER_POSTCOPY_END), REQ(VHOST_USER_MAX), }; #undef REQ @@ -889,6 +890,26 @@ vu_set_postcopy_listen(VuDev *dev, VhostUserMsg *vmsg) return false; } + +static bool +vu_set_postcopy_end(VuDev *dev, VhostUserMsg *vmsg) +{ + fprintf(stderr, "%s: Entry\n", __func__); + dev->postcopy_listening = false; + if (dev->postcopy_ufd > 0) { + close(dev->postcopy_ufd); + dev->postcopy_ufd = -1; + fprintf(stderr, "%s: Done close\n", __func__); + } + + vmsg->fd_num = 0; + vmsg->payload.u64 = 0; + vmsg->size = sizeof(vmsg->payload.u64); + vmsg->flags = VHOST_USER_VERSION | VHOST_USER_REPLY_MASK; + fprintf(stderr, "%s: exit\n", __func__); + return true; +} + static bool vu_process_message(VuDev *dev, VhostUserMsg *vmsg) { @@ -956,6 +977,8 @@ vu_process_message(VuDev *dev, VhostUserMsg *vmsg) return vu_set_postcopy_advise(dev, vmsg); case VHOST_USER_POSTCOPY_LISTEN: return vu_set_postcopy_listen(dev, vmsg); + case VHOST_USER_POSTCOPY_END: + return vu_set_postcopy_end(dev, vmsg); default: vmsg_close_fds(vmsg); vu_panic(dev, "Unhandled request: %d", vmsg->request); diff --git a/contrib/libvhost-user/libvhost-user.h b/contrib/libvhost-user/libvhost-user.h index 86e1934ddb..1665c729f0 100644 --- a/contrib/libvhost-user/libvhost-user.h +++ b/contrib/libvhost-user/libvhost-user.h @@ -65,6 +65,7 @@ typedef enum VhostUserRequest { VHOST_USER_INPUT_GET_CONFIG = 20, VHOST_USER_POSTCOPY_ADVISE = 23, VHOST_USER_POSTCOPY_LISTEN = 24, + VHOST_USER_POSTCOPY_END = 25, VHOST_USER_MAX } VhostUserRequest; diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c index 74e4313782..b29a141703 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -69,6 +69,7 @@ typedef enum VhostUserRequest { VHOST_USER_IOTLB_MSG = 22, VHOST_USER_POSTCOPY_ADVISE = 23, VHOST_USER_POSTCOPY_LISTEN = 24, + VHOST_USER_POSTCOPY_END = 25, VHOST_USER_MAX } VhostUserRequest;