Re: [libvirt] [PATCH 3/4] domain_conf: Add support for iothreads in disk definition

On 08/26/2014 12:04 PM, Ján Tomko wrote: > On 08/26/2014 02:38 AM, John Ferlan wrote: >> Add a new disk "driver" attribute "iothread" to be parsed as the thread >> number for the disk to use. In order to more easily facilitate the usage >> and configuration of the iothread, a "zero" for the attribute indicates >> iothreads are not supported for the device and a positive value indicates >> the specific thread to try and use. >> >> Signed-off-by: John Ferlan <jferlan(a)redhat.com&gt; >> --- >> docs/formatdomain.html.in | 8 ++++++++ >> docs/schemas/domaincommon.rng | 13 +++++++++++++ >> src/conf/domain_conf.c | 24 +++++++++++++++++++++++- >> src/conf/domain_conf.h | 2 ++ >> 4 files changed, 46 insertions(+), 1 deletion(-) >> > >> @@ -11968,6 +11980,14 @@ virDomainDefParseXML(xmlDocPtr xml, >> goto error; >> } >> def->iothreads = count; >> + >> + /* Create a bitmap for inuse threads - noting that entries are >> + * numbered 1..def->iothreads since 0 (zero) iothreads means >> + * nothing and assigning a disk to an IOThread requires at least a >> + * thread# > 0 since a zero would indicate no IOThread for the disk >> + */ >> + if (!(def->iothreadmap = virBitmapNew(def->iothreads+1))) >> + goto error; >> } > > Do you plan to do multiple disks on a single iothread in the followup patches? > Or is that a configuration that doesn't make sense? > I would say it doesn't make sense and from the bz I have the comment is "2. 1 IOThread per device" (bz 1101574 if you care to read although it's mostly private comments though which is why I didn't put it in the patches).