From: Matthew Wilcox <willy@infradead.org>
To: Christoph Hellwig <hch@lst.de>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Kent Overstreet <kent.overstreet@gmail.com>,
linux-mm@kvack.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 04/13] mm: handle readahead in generic_file_buffered_read_pagenotuptodate
Date: Sat, 31 Oct 2020 17:06:46 +0000 [thread overview]
Message-ID: <20201031170646.GT27442@casper.infradead.org> (raw)
In-Reply-To: <20201031090004.452516-5-hch@lst.de>
On Sat, Oct 31, 2020 at 09:59:55AM +0100, Christoph Hellwig wrote:
> Move the calculation of the per-page variables and the readahead handling
> from the only caller into generic_file_buffered_read_pagenotuptodate,
> which now becomes a routine to handle everything related to bringing
> one page uptodate and thus is renamed to filemap_read_one_page.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
> mm/filemap.c | 63 +++++++++++++++++++++++-----------------------------
> 1 file changed, 28 insertions(+), 35 deletions(-)
>
> diff --git a/mm/filemap.c b/mm/filemap.c
> index bae5b905aa7bdc..5cdf8090d4e12c 100644
> --- a/mm/filemap.c
> +++ b/mm/filemap.c
> @@ -2217,13 +2217,26 @@ static int filemap_readpage(struct kiocb *iocb, struct page *page)
> return error;
> }
>
> -static int generic_file_buffered_read_pagenotuptodate(struct kiocb *iocb,
> - struct iov_iter *iter, struct page *page, loff_t pos,
> - loff_t count, bool first)
> +static int filemap_make_page_uptodate(struct kiocb *iocb, struct iov_iter *iter,
> + struct page *page, pgoff_t pg_index, bool first)
I prefer "filemap_update_page".
I don't understand why you pass in pg_index instead of using page->index.
We dereferenced the page pointer already to check PageReadahead(), so
there's no performance issue here.
Also, if filemap_find_get_pages() stops on the first !Uptodate or
Readahead page, as I had it in my patchset, then we don't need the loop
at all -- filemap_read_pages() looks like:
nr_pages = filemap_find_get_pages(iocb, iter, pages, nr);
if (!nr_pages) {
pages[0] = filemap_create_page(iocb, iter);
if (!IS_ERR_OR_NULL(pages[0]))
return 1;
if (!pages[0])
goto retry;
return PTR_ERR(pages[0]);
}
page = pages[nr_pages - 1];
if (PageUptodate(page) && !PageReadahead(page))
return nr_pages;
err = filemap_update_page(iocb, iter, page);
if (!err)
return nr_pages;
nr_pages -= 1;
if (nr_pages)
return nr_pages;
return err;
next prev parent reply other threads:[~2020-10-31 17:06 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-31 8:59 clean up the generic pagecache read helpers Christoph Hellwig
2020-10-31 8:59 ` [PATCH 01/13] mm: simplify generic_file_buffered_read_readpage Christoph Hellwig
2020-10-31 8:59 ` [PATCH 02/13] mm: simplify generic_file_buffered_read_pagenotuptodate Christoph Hellwig
2020-10-31 8:59 ` [PATCH 03/13] mm: lift the nowait checks into generic_file_buffered_read_pagenotuptodate Christoph Hellwig
2020-10-31 8:59 ` [PATCH 04/13] mm: handle readahead in generic_file_buffered_read_pagenotuptodate Christoph Hellwig
2020-10-31 17:06 ` Matthew Wilcox [this message]
2020-11-01 10:31 ` Christoph Hellwig
2020-11-01 10:49 ` Matthew Wilcox
2020-11-01 10:51 ` Christoph Hellwig
2020-11-01 10:51 ` Christoph Hellwig
2020-11-01 11:04 ` Matthew Wilcox
2020-11-01 11:52 ` Christoph Hellwig
2020-11-01 14:55 ` Matthew Wilcox
2020-11-02 8:18 ` Christoph Hellwig
2020-10-31 8:59 ` [PATCH 05/13] mm: simplify generic_file_buffered_read_no_cached_page Christoph Hellwig
2020-10-31 16:20 ` Matthew Wilcox
2020-10-31 16:28 ` Matthew Wilcox
2020-11-01 10:29 ` Christoph Hellwig
2020-10-31 8:59 ` [PATCH 06/13] mm: factor out a filemap_find_get_pages helper Christoph Hellwig
2020-10-31 8:59 ` [PATCH 07/13] mm: refactor generic_file_buffered_read_get_pages Christoph Hellwig
2020-11-01 11:18 ` Matthew Wilcox
2020-10-31 8:59 ` [PATCH 08/13] mm: move putting the page on error out of filemap_readpage Christoph Hellwig
2020-10-31 9:00 ` [PATCH 09/13] mm: move putting the page on error out of filemap_make_page_uptodate Christoph Hellwig
2020-10-31 9:00 ` [PATCH 10/13] mm: open code readahead in filemap_new_page Christoph Hellwig
2020-11-01 11:20 ` Matthew Wilcox
2020-10-31 9:00 ` [PATCH 11/13] mm: streamline the partially uptodate checks in filemap_make_page_uptodate Christoph Hellwig
2020-11-01 11:23 ` Matthew Wilcox
2020-10-31 9:00 ` [PATCH 12/13] mm: rename generic_file_buffered_read to filemap_read Christoph Hellwig
2020-10-31 9:00 ` [PATCH 13/13] mm: simplify generic_file_read_iter Christoph Hellwig
2020-10-31 15:42 ` clean up the generic pagecache read helpers Matthew Wilcox
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20201031170646.GT27442@casper.infradead.org \
--to=willy@infradead.org \
--cc=akpm@linux-foundation.org \
--cc=hch@lst.de \
--cc=kent.overstreet@gmail.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-mm@kvack.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).