On Thu, Apr 11, 2019 at 06:40:59PM +0200, Johannes Thumshirn wrote: > Currently read_extent_buffer_pages() uses a 4 pass algorithm to read an > extent buffer's pages from disk, all 4 stages looping over all pages of > the extent buffer. > > 1) Loop over all pages and lock them. > 2) Loop over all pages and see if one is not marked as PageUptodate, so we > can break out of the function early. > 3) Loop over all pages and if the page is !PageUptodate read the page, > otherwise unlock the page. > 4) Loop over all pages and wait for stable pages. > > Unify the 1st two for loops, we can count the number of uptodate pages > after we have locked them without the need for re-starting the loop.
Effectively reverting 2571e739677f1e4c0c63f5ed49adcc0857923625 that fixed a bug. Please have a look if something has really changed so that the split loops are no longer necessary.
