[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20240201135231.tgnn7cnlmtqh5n4f@quack3>
Date: Thu, 1 Feb 2024 14:52:31 +0100
From: Jan Kara <jack@...e.cz>
To: Matthew Wilcox <willy@...radead.org>
Cc: Liu Shixin <liushixin2@...wei.com>,
Alexander Viro <viro@...iv.linux.org.uk>,
Christian Brauner <brauner@...nel.org>, Jan Kara <jack@...e.cz>,
Andrew Morton <akpm@...ux-foundation.org>,
linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
linux-mm@...ck.org
Subject: Re: [PATCH 1/2] mm/readahead: stop readahead loop if memcg charge
fails
On Thu 01-02-24 13:47:03, Matthew Wilcox wrote:
> On Thu, Feb 01, 2024 at 06:08:34PM +0800, Liu Shixin wrote:
> > @@ -247,9 +248,12 @@ void page_cache_ra_unbounded(struct readahead_control *ractl,
> > folio = filemap_alloc_folio(gfp_mask, 0);
> > if (!folio)
> > break;
> > - if (filemap_add_folio(mapping, folio, index + i,
> > - gfp_mask) < 0) {
> > +
> > + ret = filemap_add_folio(mapping, folio, index + i, gfp_mask);
> > + if (ret < 0) {
> > folio_put(folio);
> > + if (ret == -ENOMEM)
> > + break;
>
> No, that's too early. You've still got a batch of pages which were
> successfully added; you have to read them. You were only off by one
> line though ;-)
There's a read_pages() call just outside of the loop so this break is
actually fine AFAICT.
Honza
--
Jan Kara <jack@...e.com>
SUSE Labs, CR
Powered by blists - more mailing lists