qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-devel] [PATCH v4 3/6] vhost: Add temporary memory structure


From: Dr. David Alan Gilbert
Subject: Re: [Qemu-devel] [PATCH v4 3/6] vhost: Add temporary memory structure
Date: Fri, 15 Dec 2017 13:15:22 +0000
User-agent: Mutt/1.9.1 (2017-09-22)

* Igor Mammedov (address@hidden) wrote:
> On Wed, 13 Dec 2017 18:08:04 +0000
> "Dr. David Alan Gilbert (git)" <address@hidden> wrote:
> 
> > From: "Dr. David Alan Gilbert" <address@hidden>
> > 
> > Add a 2nd 'vhost_memory' structure that will be used to build
> > the new version as the listener iterates over the address space.
> I'd suggest to add temporary 'mem_sections' instead and
> create/use/free temporary 'vhost_memory' structure at commit time,
> (1 less duplicated data set to keep in memory)

I don't see how this leads to less duplication;  I still end up with
one set of temporary structures, and the sections use Int128 which
is a pain to work with in the comparison/merging code.

Dave

> > 
> > Signed-off-by: Dr. David Alan Gilbert <address@hidden>
> > ---
> >  hw/virtio/vhost.c         | 3 +++
> >  include/hw/virtio/vhost.h | 1 +
> >  2 files changed, 4 insertions(+)
> > 
> > diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
> > index c7ce7baf9b..4523f45587 100644
> > --- a/hw/virtio/vhost.c
> > +++ b/hw/virtio/vhost.c
> > @@ -632,6 +632,8 @@ static void vhost_begin(MemoryListener *listener)
> >                                           memory_listener);
> >      dev->mem_changed_end_addr = 0;
> >      dev->mem_changed_start_addr = -1;
> > +
> > +    dev->tmp_mem = g_malloc0(offsetof(struct vhost_memory, regions));
> >  }
> >  
> >  static void vhost_commit(MemoryListener *listener)
> > @@ -641,6 +643,7 @@ static void vhost_commit(MemoryListener *listener)
> >      uint64_t log_size;
> >      int r;
> >  
> > +    g_free(dev->tmp_mem);
> >      if (!dev->memory_changed) {
> >          return;
> >      }
> > diff --git a/include/hw/virtio/vhost.h b/include/hw/virtio/vhost.h
> > index 467dc7794b..41f9e569be 100644
> > --- a/include/hw/virtio/vhost.h
> > +++ b/include/hw/virtio/vhost.h
> > @@ -70,6 +70,7 @@ struct vhost_dev {
> >      bool memory_changed;
> >      hwaddr mem_changed_start_addr;
> >      hwaddr mem_changed_end_addr;
> > +    struct vhost_memory *tmp_mem;
> >      const VhostOps *vhost_ops;
> >      void *opaque;
> >      struct vhost_log *log;
> 
--
Dr. David Alan Gilbert / address@hidden / Manchester, UK



reply via email to

[Prev in Thread] Current Thread [Next in Thread]