Re: [PATCH v3 04/11] readahead: rework loop in page_cache_ra_unbounded()

[Pankaj Raghav (Samsung)]

On Mon, Mar 25, 2024 at 06:41:01PM +0000, Matthew Wilcox wrote:
> On Wed, Mar 13, 2024 at 06:02:46PM +0100, Pankaj Raghav (Samsung) wrote:
> > @@ -239,8 +239,8 @@ void page_cache_ra_unbounded(struct readahead_control *ractl,
> >  			 * not worth getting one just for that.
> >  			 */
> >  			read_pages(ractl);
> > -			ractl->_index++;
> > -			i = ractl->_index + ractl->_nr_pages - index - 1;
> > +			ractl->_index += folio_nr_pages(folio);
> > +			i = ractl->_index + ractl->_nr_pages - index;
> >  			continue;
> >  		}
> >  
> > @@ -252,13 +252,14 @@ void page_cache_ra_unbounded(struct readahead_control *ractl,
> >  			folio_put(folio);
> >  			read_pages(ractl);
> >  			ractl->_index++;
> > -			i = ractl->_index + ractl->_nr_pages - index - 1;
> > +			i = ractl->_index + ractl->_nr_pages - index;
> >  			continue;
> >  		}
> 
> You changed index++ in the first hunk, but not the second hunk.  Is that
> intentional?
After having some back and forth with Hannes, I see where the confusion
is coming from.

I intended this to be a non-functional change that helps with adding 
min_order support later.

As this is a non-functional change, I will move this patch to be at the
start of the series as preparation patches before we start adding min_order
helpers and support.

--
Pankaj