Re: [PATCH 2/2] readahead: improve sequential read detection

From: Ram
Date: Wed Mar 09 2005 - 19:20:17 EST


On Wed, 2005-03-09 at 16:03, Steven Pratt wrote:
> Ram wrote:
>
> >On Wed, 2005-03-02 at 11:08, Oleg Nesterov wrote:
> >
> >
> >..snip...
> >
> >
> >
> >>@@ -527,7 +527,7 @@ page_cache_readahead(struct address_spac
> >> }
> >>
> >> out:
> >>- return newsize;
> >>+ return ra->prev_page + 1;
> >>
> >>
> >
> >This change introduces one key behavioural change in
> >page_cache_readahead(). Instead of returning the number-of-pages
> >successfully read, it now returns the next-page-index which is yet to be
> >read. Was this essential?
> >
> >
> >
> and unless filmap.c was changed accordingly this is broken.. need. to
> look at this more.


Oleg has taken care of it in filemap.c whereever page_cache_readahead()
is called. So its not a bug as such. But I dont think it was necessary.
Doing so takes care of 1-line code reduction in filemap.c which is the
only plus point.

RP

> >
> >
>

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