Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Fri, 31 Jan 2020 13:19:09 +1100
From:   Dave Chinner <david@fromorbit.com>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     linux-fsdevel@vger.kernel.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 11/12] fuse: Convert from readpages to readahead
Message-ID: <20200131021909.GC18575@dread.disaster.area>
References: <20200125013553.24899-1-willy@infradead.org>
 <20200125013553.24899-12-willy@infradead.org>
 <20200129010829.GK18610@dread.disaster.area>
 <20200130213533.GN6615@bombadil.infradead.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20200130213533.GN6615@bombadil.infradead.org>
User-Agent: Mutt/1.10.1 (2018-07-13)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Thu, Jan 30, 2020 at 01:35:33PM -0800, Matthew Wilcox wrote:
> On Wed, Jan 29, 2020 at 12:08:29PM +1100, Dave Chinner wrote:
> > On Fri, Jan 24, 2020 at 05:35:52PM -0800, Matthew Wilcox wrote:
> > > +	while (nr_pages--) {
> > > +		struct page *page = readahead_page(mapping, start++);
> > > +		int err = fuse_readpages_fill(&data, page);
> > > +
> > > +		if (!err)
> > > +			continue;
> > > +		nr_pages++;
> > > +		goto out;
> > >  	}
> > 
> > That's some pretty convoluted logic. Perhaps:
> > 
> > 	for (; nr_pages > 0 ; nr_pages--) {
> > 		struct page *page = readahead_page(mapping, start++);
> > 
> > 		if (fuse_readpages_fill(&data, page))
> > 			goto out;
> > 	}
> 
> I have a bit of an aversion to that style of for loop ... I like this
> instead:
> 
>         while (nr_pages) {
>                 struct page *page = readahead_page(mapping, start++);
> 
>                 if (fuse_readpages_fill(&data, page) != 0)
>                         goto out;
>                 nr_pages--;
>         }

yup, that's also fine.

-Dave.
-- 
Dave Chinner
david@fromorbit.com