Messages in this thread | | | Date | Tue, 19 Feb 2013 10:56:27 -0800 (PST) | From | Hugh Dickins <> | Subject | Re: Should a swapped out page be deleted from swap cache? |
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On Tue, 19 Feb 2013, Ric Mason wrote: > > There is a call of try_to_free_swap in function swap_writepage, if > swap_writepage is call from shrink_page_list path, PageSwapCache(page) == > trure, PageWriteback(page) maybe false, page_swapcount(page) == 0, then will > delete the page from swap cache and free swap slot, where I miss?
That's correct. PageWriteback is sure to be false there. page_swapcount usually won't be 0 there, but sometimes it will be, and in that case we do want to delete from swap cache and free the swap slot.
Hugh
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