From: Andrew Morton <akpm@osdl.org>
To: Daniel McNeil <daniel@osdl.org>
Cc: suparna@in.ibm.com, janetmor@us.ibm.com, pbadari@us.ibm.com,
linux-aio@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH linux-2.6.1-rc1-mm1] filemap_fdatawait.patch
Date: Wed, 31 Dec 2003 15:42:39 -0800 [thread overview]
Message-ID: <20031231154239.7c4d140e.akpm@osdl.org> (raw)
In-Reply-To: <1072910061.712.67.camel@ibm-c.pdx.osdl.net>
Daniel McNeil <daniel@osdl.org> wrote:
>
> The other potential race in filemap_fdatawait() was that it
> removed the page from the locked list while waiting for a writeback
> and if there was a 2nd filemap_fdatawait() running on another cpu,
> it would not wait for the page being written since it would never see
> it on the list.
That would only happen if one thread or the other was not running under
i_sem. The only path I see doing that is in generic_file_direct_IO()?
> + /*
> + * If the page is locked, it might be in process of being
> + * setup for writeback but without PG_writeback set
> + * and with PG_dirty cleared.
> + * (PG_dirty is cleared BEFORE PG_writeback is set)
> + * So, wait for the PG_locked to clear, then start over.
> + */
> + if (PageLocked(page)) {
> + page_cache_get(page);
> + spin_unlock(&mapping->page_lock);
> + wait_on_page_locked(page);
> + page_cache_release(page);
> + goto restart;
> + }
Why is this a problem which needs addressing here? If some other thread is
in the process of starting I/O against this page then the page must have
been clean when this thread ran filemap_fdatawrite()?
next prev parent reply other threads:[~2003-12-31 23:42 UTC|newest]
Thread overview: 58+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <3FCD4B66.8090905@us.ibm.com>
2003-12-06 1:29 ` [PATCH linux-2.6.0-test10-mm1] dio-read-race-fix Daniel McNeil
2003-12-08 18:23 ` Daniel McNeil
2003-12-12 0:51 ` Daniel McNeil
2003-12-17 1:25 ` [PATCH linux-2.6.0-test10-mm1] filemap_fdatawait.patch Daniel McNeil
2003-12-17 2:03 ` Andrew Morton
2003-12-17 19:25 ` Daniel McNeil
2003-12-17 20:17 ` Janet Morgan
2003-12-31 9:18 ` Suparna Bhattacharya
2003-12-31 9:35 ` Andrew Morton
2003-12-31 9:55 ` Suparna Bhattacharya
2003-12-31 9:59 ` Andrew Morton
2003-12-31 10:09 ` Suparna Bhattacharya
2003-12-31 10:10 ` Andrew Morton
2003-12-31 10:48 ` Suparna Bhattacharya
2003-12-31 10:53 ` Andrew Morton
2003-12-31 10:54 ` Andrew Morton
2003-12-31 11:17 ` Andrew Morton
2003-12-31 22:34 ` [PATCH linux-2.6.1-rc1-mm1] filemap_fdatawait.patch Daniel McNeil
2003-12-31 22:41 ` [PATCH linux-2.6.1-rc1-mm1] aiodio_fallback_bio_count.patch Daniel McNeil
2003-12-31 23:46 ` Andrew Morton
2004-01-02 5:14 ` Suparna Bhattacharya
2004-01-02 7:46 ` Andrew Morton
2004-01-05 3:55 ` Suparna Bhattacharya
2004-01-05 5:06 ` Andrew Morton
2004-01-05 5:28 ` Suparna Bhattacharya
2004-01-05 5:28 ` Andrew Morton
2004-01-05 6:06 ` Suparna Bhattacharya
2004-01-05 6:14 ` Lincoln Dale
2003-12-31 22:47 ` [PATCH linux-2.6.1-rc1-mm1] dio_isize.patch Daniel McNeil
2003-12-31 23:42 ` Andrew Morton [this message]
2004-01-02 4:20 ` [PATCH linux-2.6.1-rc1-mm1] filemap_fdatawait.patch Suparna Bhattacharya
2004-01-02 4:36 ` Andrew Morton
2004-01-02 5:50 ` [PATCH linux-2.6.0-test10-mm1] filemap_fdatawait.patch Suparna Bhattacharya
2004-01-02 7:31 ` Andrew Morton
2004-01-05 13:49 ` Marcelo Tosatti
2004-01-05 20:27 ` Andrew Morton
2004-03-29 15:44 ` Marcelo Tosatti
2004-01-11 23:14 ` Janet Morgan
2004-01-11 23:44 ` Andrew Morton
2004-01-12 18:00 ` filemap_fdatawait.patch Daniel McNeil
2004-01-12 19:39 ` [PATCH linux-2.6.0-test10-mm1] filemap_fdatawait.patch Janet Morgan
2004-01-12 19:46 ` Daniel McNeil
2004-01-13 4:12 ` Janet Morgan
2003-12-30 4:53 ` [PATCH linux-2.6.0-test10-mm1] dio-read-race-fix Suparna Bhattacharya
2003-12-31 0:29 ` Daniel McNeil
2003-12-31 6:09 ` Suparna Bhattacharya
2004-01-08 23:55 ` Daniel McNeil
2004-01-09 3:55 ` Suparna Bhattacharya
2004-02-05 1:39 ` [PATCH 2.6.2-rc3-mm1] DIO read race fix Daniel McNeil
2004-02-05 1:54 ` Badari Pulavarty
2004-02-05 2:07 ` Andrew Morton
2004-02-05 2:54 ` Janet Morgan
2004-02-05 3:19 ` Andrew Morton
2004-02-05 3:43 ` Suparna Bhattacharya
2004-02-05 5:33 ` Andrew Morton
2004-02-05 17:52 ` Daniel McNeil
2004-02-05 18:53 ` Badari Pulavarty
2004-03-29 15:41 ` [PATCH linux-2.6.0-test10-mm1] dio-read-race-fix Suparna Bhattacharya
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=20031231154239.7c4d140e.akpm@osdl.org \
--to=akpm@osdl.org \
--cc=daniel@osdl.org \
--cc=janetmor@us.ibm.com \
--cc=linux-aio@kvack.org \
--cc=linux-kernel@vger.kernel.org \
--cc=pbadari@us.ibm.com \
--cc=suparna@in.ibm.com \
/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).