Re: [Qemu-devel] [PULL 25/57] Add wrappers and handlers for sending/receiving the postcopy-ram migration messages.

[Dr. David Alan Gilbert]

* Stefan Weil (address@hidden) wrote:
> Am 16.11.2015 um 11:07 schrieb Dr. David Alan Gilbert:
> > * Stefan Weil (address@hidden) wrote:
> >> Am 10.11.2015 um 15:25 schrieb Juan Quintela:
> >>> From: "Dr. David Alan Gilbert" <address@hidden>
> >>>
> >>> The state of the postcopy process is managed via a series of messages;
> >>>    * Add wrappers and handlers for sending/receiving these messages
> >>>    * Add state variable that track the current state of postcopy
> >>>
> >>> Signed-off-by: Dr. David Alan Gilbert <address@hidden>
> >>> Reviewed-by: Amit Shah <address@hidden>
> >>> Reviewed-by: Juan Quintela <address@hidden>
> >>> Signed-off-by: Juan Quintela <address@hidden>
> >>> ---
> >>>  include/migration/migration.h |  27 +++++
> >>>  include/sysemu/sysemu.h       |  19 ++++
> >>>  migration/migration.c         |  20 ++++
> >>>  migration/savevm.c            | 254 
> >>> ++++++++++++++++++++++++++++++++++++++++++
> >>>  trace-events                  |  10 ++
> >>>  5 files changed, 330 insertions(+)
> >>>
> >> [...]
> >>> diff --git a/migration/savevm.c b/migration/savevm.c
> >> [...]
> >>> +    if (remote_hps != getpagesize())  {
> >>> +        /*
> >>> +         * Some combinations of mismatch are probably possible but it 
> >>> gets
> >>> +         * a bit more complicated.  In particular we need to place whole
> >>> +         * host pages on the dest at once, and we need to ensure that we
> >>> +         * handle dirtying to make sure we never end up sending part of
> >>> +         * a hostpage on it's own.
> >>> +         */
> >>> +        error_report("Postcopy needs matching host page sizes (s=%d 
> >>> d=%d)",
> >>> +                     (int)remote_hps, getpagesize());
> >>
> >> This statement introduces a new warning when compiling for
> >> Windows where getpagesize() returns a size_t. I'll send a patch
> >> to change that definition to return an int value.
> > 
> > Interesting; which compiler are you using; I don't think any of us testing 
> > with
> > ming hit that.
> 
> I use Debian GNU Linux jessie with package gcc-mingw-w64-x86-64.
> 
>   CC    i386-softmmu/migration/savevm.o
> migration/savevm.c: In function ‘loadvm_postcopy_handle_advise’:
> migration/savevm.c:1284:22: warning: format ‘%d’ expects argument of
> type ‘int’, but argument 3 has type ‘size_t’ [-Wformat=]
>                       (int)remote_hps, getpagesize());
>                       ^
> $ x86_64-w64-mingw32-gcc --version
> x86_64-w64-mingw32-gcc (GCC) 4.9.1
> Copyright (C) 2014 Free Software Foundation, Inc.
> This is free software; see the source for copying conditions.  There is NO
> warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Ah OK, I see that but only when I build with a 64bit mingw.

Dave
--
Dr. David Alan Gilbert / address@hidden / Manchester, UK