Messages in this thread | | | Date | Sat, 02 Nov 2002 13:48:41 -0800 | From | Andrew Morton <> | Subject | Re: Hot/cold allocation -- swsusp can not handle hot pages |
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Pavel Machek wrote: > > Hi! > > > > Swsusp counts free pages, and relies on fact that when it allocates > > > page there's one free page less. That is no longer true with hot > > > pages. > > > I attempted to work it around but it seems I am getting hot pages even > > > when I ask for cold one. This seems to fix it. Does it looks like > > > "possibly mergable" patch? > > > --- clean/mm/page_alloc.c 2002-11-01 00:37:44.000000000 +0100 > > > +++ linux-swsusp/mm/page_alloc.c 2002-11-01 22:53:47.000000000 +0100 > > > @@ -361,7 +361,7 @@ > > > unsigned long flags; > > > struct page *page = NULL; > > > > > > - if (order == 0) { > > > + if ((order == 0) && !cold) { > > > struct per_cpu_pages *pcp; > > > > > > pcp = &zone->pageset[get_cpu()].pcp[cold]; > > > > > > > This doesn't seem to be doing what you want, even if it seems to work. > > If you want there to be one free page less, then allocating it will > > work regardless. What are you looking for besides that? If it's not > > already working you want some additional semantics. Could this involve > > is_head_of_free_region()? That should be solvable with a per-cpu list > > shootdown algorithm to fully merge all the buddy bitmap things. > > I need pages I allocate to disappear from "is_head_of_free_region()", > so my counts match. >
hm. swsusp does funny things. Would it be posible to get a big-picture "how this whole thing works" story? What exactly is the nature of its relationship with the page allocator?
I'm not really sure what to suggest here. Emptying the per-cpu page pools would be tricky. Maybe a swsusp-special page allocator which goes direct to the buddy lists or something. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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