Re: [Qemu-devel] [PATCH v5 11/17] migration: Really use multiple pages at a time

[Peter Xu]

On Tue, Aug 08, 2017 at 06:06:04PM +0200, Juan Quintela wrote:
> Peter Xu <address@hidden> wrote:
> > On Mon, Jul 17, 2017 at 03:42:32PM +0200, Juan Quintela wrote:
> >
> > [...]
> >
> >>  static int multifd_send_page(uint8_t *address)
> >>  {
> >> -    int i;
> >> +    int i, j;
> >>      MultiFDSendParams *p = NULL; /* make happy gcc */
> >> +    static multifd_pages_t pages;
> >> +    static bool once;
> >> +
> >> +    if (!once) {
> >> +        multifd_init_group(&pages);
> >> +        once = true;
> >
> > Would it be good to put the "pages" into multifd_send_state? One is to
> > stick globals together; another benefit is that we can remove the
> > "once" here: we can then init the "pages" when init multifd_send_state
> > struct (but maybe with a better name?...).
> 
> I did to be able to free it.

Free it? But they a static variables, then how can we free them?

(I thought the only way to free it is putting it into
 multifd_send_state...)

Something I must have missed here. :(

> 
> > (there are similar static variables in multifd_recv_page() as well, if
> >  this one applies, then we can possibly use multifd_recv_state for
> >  that one)
> 
> Also there.
> 
> >> +    }
> >> +
> >> +    pages.iov[pages.num].iov_base = address;
> >> +    pages.iov[pages.num].iov_len = TARGET_PAGE_SIZE;
> >> +    pages.num++;
> >> +
> >> +    if (pages.num < (pages.size - 1)) {
> >> +        return UINT16_MAX;
> >
> > Nit: shall we define something for readability?  Like:
> >
> > #define  MULTIFD_FD_INVALID  UINT16_MAX
> 
> Also done.
> 
> MULTIFD_CONTINUE
> 
> But I am open to changes.

It's clear enough at least to me. Thanks!

-- 
Peter Xu