From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [Qemu-devel] [PATCH V2 11/20] tap: support enabling or disabling a queue Date: Wed, 30 Jan 2013 00:11:48 +0200 Message-ID: <20130129221148.GA1777@redhat.com> References: <1359110143-42984-1-git-send-email-jasowang@redhat.com> <1359110143-42984-12-git-send-email-jasowang@redhat.com> <5107D3B5.8050506@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Jason Wang , krkumar2@in.ibm.com, aliguori@us.ibm.com, kvm@vger.kernel.org, mprivozn@redhat.com, rusty@rustcorp.com.au, qemu-devel@nongnu.org, shajnocz@redhat.com, shiyer@redhat.com, jwhan@filewood.snu.ac.kr, gaowanlong@cn.fujitsu.com To: Blue Swirl Return-path: Received: from mx1.redhat.com ([209.132.183.28]:63511 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751483Ab3A2WHw (ORCPT ); Tue, 29 Jan 2013 17:07:52 -0500 Content-Disposition: inline In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: On Tue, Jan 29, 2013 at 08:10:26PM +0000, Blue Swirl wrote: > On Tue, Jan 29, 2013 at 1:50 PM, Jason Wang wrote: > > On 01/26/2013 03:13 AM, Blue Swirl wrote: > >> On Fri, Jan 25, 2013 at 10:35 AM, Jason Wang wrote: > >>> This patch introduce a new bit - enabled in TAPState which tracks whether a > >>> specific queue/fd is enabled. The tap/fd is enabled during initialization and > >>> could be enabled/disabled by tap_enalbe() and tap_disable() which calls platform > >>> specific helpers to do the real work. Polling of a tap fd can only done when > >>> the tap was enabled. > >>> > >>> Signed-off-by: Jason Wang > >>> --- > >>> include/net/tap.h | 2 ++ > >>> net/tap-win32.c | 10 ++++++++++ > >>> net/tap.c | 43 ++++++++++++++++++++++++++++++++++++++++--- > >>> 3 files changed, 52 insertions(+), 3 deletions(-) > >>> > >>> diff --git a/include/net/tap.h b/include/net/tap.h > >>> index bb7efb5..0caf8c4 100644 > >>> --- a/include/net/tap.h > >>> +++ b/include/net/tap.h > >>> @@ -35,6 +35,8 @@ int tap_has_vnet_hdr_len(NetClientState *nc, int len); > >>> void tap_using_vnet_hdr(NetClientState *nc, int using_vnet_hdr); > >>> void tap_set_offload(NetClientState *nc, int csum, int tso4, int tso6, int ecn, int ufo); > >>> void tap_set_vnet_hdr_len(NetClientState *nc, int len); > >>> +int tap_enable(NetClientState *nc); > >>> +int tap_disable(NetClientState *nc); > >>> > >>> int tap_get_fd(NetClientState *nc); > >>> > >>> diff --git a/net/tap-win32.c b/net/tap-win32.c > >>> index 265369c..a2cd94b 100644 > >>> --- a/net/tap-win32.c > >>> +++ b/net/tap-win32.c > >>> @@ -764,3 +764,13 @@ void tap_set_vnet_hdr_len(NetClientState *nc, int len) > >>> { > >>> assert(0); > >>> } > >>> + > >>> +int tap_enable(NetClientState *nc) > >>> +{ > >>> + assert(0); > >> abort() > > > > This is just to be consistent with the reset of the helpers in this file. > >> > >>> +} > >>> + > >>> +int tap_disable(NetClientState *nc) > >>> +{ > >>> + assert(0); > >>> +} > >>> diff --git a/net/tap.c b/net/tap.c > >>> index 67080f1..95e557b 100644 > >>> --- a/net/tap.c > >>> +++ b/net/tap.c > >>> @@ -59,6 +59,7 @@ typedef struct TAPState { > >>> unsigned int write_poll : 1; > >>> unsigned int using_vnet_hdr : 1; > >>> unsigned int has_ufo: 1; > >>> + unsigned int enabled : 1; > >> bool without bit field? > > > > Also to be consistent with other field. If you wish I can send patches > > to convert all those bit field to bool on top of this series. > > That would be nice, likewise for the assert(0). OK so let's go ahead with this patchset as is, and a cleanup patch will be send after 1.4 then. > > > > Thanks > >>> VHostNetState *vhost_net; > >>> unsigned host_vnet_hdr_len; > >>> } TAPState; > >>> @@ -72,9 +73,9 @@ static void tap_writable(void *opaque); > >>> static void tap_update_fd_handler(TAPState *s) > >>> { > >>> qemu_set_fd_handler2(s->fd, > >>> - s->read_poll ? tap_can_send : NULL, > >>> - s->read_poll ? tap_send : NULL, > >>> - s->write_poll ? tap_writable : NULL, > >>> + s->read_poll && s->enabled ? tap_can_send : NULL, > >>> + s->read_poll && s->enabled ? tap_send : NULL, > >>> + s->write_poll && s->enabled ? tap_writable : NULL, > >>> s); > >>> } > >>> > >>> @@ -339,6 +340,7 @@ static TAPState *net_tap_fd_init(NetClientState *peer, > >>> s->host_vnet_hdr_len = vnet_hdr ? sizeof(struct virtio_net_hdr) : 0; > >>> s->using_vnet_hdr = 0; > >>> s->has_ufo = tap_probe_has_ufo(s->fd); > >>> + s->enabled = 1; > >>> tap_set_offload(&s->nc, 0, 0, 0, 0, 0); > >>> /* > >>> * Make sure host header length is set correctly in tap: > >>> @@ -737,3 +739,38 @@ VHostNetState *tap_get_vhost_net(NetClientState *nc) > >>> assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP); > >>> return s->vhost_net; > >>> } > >>> + > >>> +int tap_enable(NetClientState *nc) > >>> +{ > >>> + TAPState *s = DO_UPCAST(TAPState, nc, nc); > >>> + int ret; > >>> + > >>> + if (s->enabled) { > >>> + return 0; > >>> + } else { > >>> + ret = tap_fd_enable(s->fd); > >>> + if (ret == 0) { > >>> + s->enabled = 1; > >>> + tap_update_fd_handler(s); > >>> + } > >>> + return ret; > >>> + } > >>> +} > >>> + > >>> +int tap_disable(NetClientState *nc) > >>> +{ > >>> + TAPState *s = DO_UPCAST(TAPState, nc, nc); > >>> + int ret; > >>> + > >>> + if (s->enabled == 0) { > >>> + return 0; > >>> + } else { > >>> + ret = tap_fd_disable(s->fd); > >>> + if (ret == 0) { > >>> + qemu_purge_queued_packets(nc); > >>> + s->enabled = 0; > >>> + tap_update_fd_handler(s); > >>> + } > >>> + return ret; > >>> + } > >>> +} > >>> -- > >>> 1.7.1 > >>> > >>> > >