On 05/28/2010 07:49 PM, tytso@xxxxxxx wrote:
This doesn't fix a bug; it's to make it easy for Dave Chinner to make some changes to fix XFS's performance and to undo some ext4-specific changes to write_cache_pages(). I'm not sure there's a good reason to backport this to 2.6.27.y....
The difference is that, 2.6.27's write_cache_pages() in page-writeback.c still updates wbc->nr_to_write, since the patch which changed that behavior was dropped from .27-rc2 due to the XFS regression it causes on mainline. ext4 appears to want the behavior of write_cache_pages which does not update wbc->nr_to_write. This write_cache_pages_da() does what ext4 wants, without introducing the XFS regression. So I believe it is needed.
Did I mis-judge? Rgds, Jayson -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
