On Mon, Jun 03, 2019 at 01:40:13PM +0800, Peter Xu wrote: > >Ah I see, thanks for the pointer. Then I would agree it's fine. > >I'm not an expert of TCG - I'm curious on why all those three dirty >bitmaps need to be set at the very beginning. IIUC at least the VGA >bitmap should not require that (so IMHO we should be fine to have all >zeros with VGA bitmap for ramblocks, and we only set them when the >guest touches them). Migration bitmap should be special somehow but I >don't know much on TCG/TLB part I'd confess so I can't say. In other >words, if migration is the only one that requires this "all-1" >initialization then IMHO we may consider to remove the other part >rather than here in migration because that's what we'd better to be >sure with.
I am not sure about the background here, so I didn't make a change at this place. > >And even if you want to remove this, I still have two suggestions: > >(1) proper comment here above bmap on the above fact that although > bmap is not set here but it's actually set somewhere else because > we'll sooner or later copy all 1s from the ramblock bitmap > >(2) imho you can move "migration_dirty_pages = 0" into > ram_list_init_bitmaps() too to let them be together > I will address these two comments and send v2. Thanks. >-- >Peter Xu -- Wei Yang Help you, Help me
