On Mon, Mar 12, 2018 at 05:30:12PM +0000, Dr. David Alan Gilbert wrote:
> * Peter Xu (pet...@redhat.com) wrote:
> > After we updated the dirty bitmaps of ramblocks, we also need to update
> > the critical fields in RAMState to make sure it is ready for a resume.
> >
> > Signed-off-by: Peter Xu <pet...@redhat.com>
> > ---
> > migration/ram.c | 45 ++++++++++++++++++++++++++++++++++++++++++++-
> > migration/trace-events | 1 +
> > 2 files changed, 45 insertions(+), 1 deletion(-)
> >
> > diff --git a/migration/ram.c b/migration/ram.c
> > index 196b1ba876..5cd9f43728 100644
> > --- a/migration/ram.c
> > +++ b/migration/ram.c
> > @@ -2254,6 +2254,41 @@ static int ram_init_all(RAMState **rsp)
> > return 0;
> > }
> >
> > +static void ram_state_resume_prepare(RAMState *rs, QEMUFile *out)
> > +{
> > + RAMBlock *block;
> > + uint64_t pages = 0;
> > +
> > + /*
> > + * Postcopy is not using xbzrle/compression, so no need for that.
> > + * Also, since source are already halted, we don't need to care
> > + * about dirty page logging as well.
> > + */
> > +
> > + RAMBLOCK_FOREACH(block) {
> > + pages += bitmap_count_one(block->bmap,
> > + block->used_length >> TARGET_PAGE_BITS);
> > + }
> > +
> > + /* This may not be aligned with current bitmaps. Recalculate. */
> > + rs->migration_dirty_pages = pages;
> > +
> > + rs->last_seen_block = NULL;
> > + rs->last_sent_block = NULL;
> > + rs->last_page = 0;
> > + rs->last_version = ram_list.version;
> > + /*
> > + * Disable the bulk stage, otherwise we'll resend the whole RAM no
> > + * matter what we have sent.
> > + */
> > + rs->ram_bulk_stage = false;
> > +
> > + /* Update RAMState cache of output QEMUFile */
> > + rs->f = out;
> > +
> > + trace_ram_state_resume_prepare(pages);
> > +}
> > +
> > /*
> > * Each of ram_save_setup, ram_save_iterate and ram_save_complete has
> > * long-running RCU critical section. When rcu-reclaims in the code
> > @@ -3182,8 +3217,16 @@ out:
> > static int ram_resume_prepare(MigrationState *s, void *opaque)
> > {
> > RAMState *rs = *(RAMState **)opaque;
> > + int ret;
> >
> > - return ram_dirty_bitmap_sync_all(s, rs);
> > + ret = ram_dirty_bitmap_sync_all(s, rs);
> > + if (ret) {
> > + return ret;
> > + }
> > +
> > + ram_state_resume_prepare(rs, s->to_dst_file);
> > +
> > + return 0;
> > }
> >
> > static SaveVMHandlers savevm_ram_handlers = {
> > diff --git a/migration/trace-events b/migration/trace-events
> > index 45b1d89217..f5913ff51c 100644
> > --- a/migration/trace-events
> > +++ b/migration/trace-events
> > @@ -88,6 +88,7 @@ ram_dirty_bitmap_reload_complete(char *str) "%s"
> > ram_dirty_bitmap_sync_start(void) ""
> > ram_dirty_bitmap_sync_wait(void) ""
> > ram_dirty_bitmap_sync_complete(void) ""
> > +ram_state_resume_prepare(long v) "%ld"
>
> Actually, just noticed that's a long but the values passed is now
> uint64_t - be careful.
Yeah, will fix that up. Thanks,
--
Peter Xu
