Messages in this thread | | | Date | Tue, 6 Nov 2007 18:23:44 -0800 (PST) | From | Christoph Lameter <> | Subject | Re: [RFC PATCH 3/10] define page_file_cache |
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On Sat, 3 Nov 2007, Rik van Riel wrote:
> Define page_file_cache() function to answer the question: > is page backed by a file?
Well its not clear what is meant by a file in the first place. By file you mean disk space in contrast to ram based filesystems?
I think we could add a flag to the bdi to indicate wheter the backing store is a disk file. In fact you can also deduce if if a device has no writeback capability set in the BDI.
> Unfortunately this needs to use a page flag, since the > PG_swapbacked state needs to be preserved all the way > to the point where the page is last removed from the > LRU. Trying to derive the status from other info in > the page resulted in wrong VM statistics in earlier > split VM patchsets.
The bdi may avoid that extra flag. - 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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