From: Sha Zhengju <handai.szj@gmail.com>
To: Sage Weil <sage@inktank.com>
Cc: "Yan, Zheng" <ukernel@gmail.com>,
"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
ceph-devel <ceph-devel@vger.kernel.org>,
linux-mm <linux-mm@kvack.org>, Cgroups <cgroups@vger.kernel.org>,
Michal Hocko <mhocko@suse.cz>,
KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
Glauber Costa <glommer@gmail.com>,
Greg Thelen <gthelen@google.com>,
Wu Fengguang <fengguang.wu@intel.com>,
Andrew Morton <akpm@linux-foundation.org>,
Sha Zhengju <handai.szj@taobao.com>
Subject: Re: [PATCH V5 2/8] fs/ceph: vfs __set_page_dirty_nobuffers interface instead of doing it inside filesystem
Date: Fri, 2 Aug 2013 18:04:17 +0800 [thread overview]
Message-ID: <CAFj3OHVXvtr5BDMrGatHZi7M9y+dh1ZKRMQZGjZmNBcg3pNQtw@mail.gmail.com> (raw)
In-Reply-To: <alpine.DEB.2.00.1308011121080.22584@cobra.newdream.net>
On Fri, Aug 2, 2013 at 2:27 AM, Sage Weil <sage@inktank.com> wrote:
> On Thu, 1 Aug 2013, Yan, Zheng wrote:
>> On Thu, Aug 1, 2013 at 7:51 PM, Sha Zhengju <handai.szj@gmail.com> wrote:
>> > From: Sha Zhengju <handai.szj@taobao.com>
>> >
>> > Following we will begin to add memcg dirty page accounting around
>> __set_page_dirty_
>> > {buffers,nobuffers} in vfs layer, so we'd better use vfs interface to
>> avoid exporting
>> > those details to filesystems.
>> >
>> > Signed-off-by: Sha Zhengju <handai.szj@taobao.com>
>> > ---
>> > fs/ceph/addr.c | 13 +------------
>> > 1 file changed, 1 insertion(+), 12 deletions(-)
>> >
>> > diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
>> > index 3e68ac1..1445bf1 100644
>> > --- a/fs/ceph/addr.c
>> > +++ b/fs/ceph/addr.c
>> > @@ -76,7 +76,7 @@ static int ceph_set_page_dirty(struct page *page)
>> > if (unlikely(!mapping))
>> > return !TestSetPageDirty(page);
>> >
>> > - if (TestSetPageDirty(page)) {
>> > + if (!__set_page_dirty_nobuffers(page)) {
>> it's too early to set the radix tree tag here. We should set page's snapshot
>> context and increase the i_wrbuffer_ref first. This is because once the tag
>> is set, writeback thread can find and start flushing the page.
>
> Unfortunately I only remember being frustrated by this code. :) Looking
> at it now, though, it seems like the minimum fix is to set the
> page->private before marking the page dirty. I don't know the locking
> rules around that, though. If that is potentially racy, maybe the safest
> thing would be if __set_page_dirty_nobuffers() took a void* to set
> page->private to atomically while holding the tree_lock.
>
Sorry, I don't catch the point of your last sentence... Could you
please explain it again?
I notice there is a check in __set_page_dirty_nobuffers():
WARN_ON_ONCE(!PagePrivate(page) && !PageUptodate(page));
So does it mean we can only set page->private after it? but if so the
__mark_inode_dirty is still ahead of setting snapc.
Thanks,
Sha
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2013-08-02 10:04 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1375357402-9811-1-git-send-email-handai.szj@taobao.com>
2013-08-01 11:51 ` [PATCH V5 2/8] fs/ceph: vfs __set_page_dirty_nobuffers interface instead of doing it inside filesystem Sha Zhengju
2013-08-01 15:19 ` Yan, Zheng
2013-08-01 18:27 ` Sage Weil
2013-08-02 10:04 ` Sha Zhengju [this message]
[not found] ` <CAFj3OHVXvtr5BDMrGatHZi7M9y+dh1ZKRMQZGjZmNBcg3pNQtw-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-08-02 20:30 ` Sage Weil
2013-08-03 8:58 ` Sha Zhengju
2013-08-02 9:04 ` Sha Zhengju
2013-08-02 13:11 ` Yan, Zheng
2013-08-01 11:53 ` [PATCH V5 4/8] memcg: add per cgroup dirty pages accounting Sha Zhengju
2013-08-01 11:54 ` [PATCH V5 5/8] memcg: add per cgroup writeback " Sha Zhengju
2013-08-01 14:53 ` Michal Hocko
[not found] ` <20130801145302.GJ5198-2MMpYkNvuYDjFM9bn6wA6Q@public.gmane.org>
2013-08-03 9:25 ` Sha Zhengju
[not found] ` <CAFj3OHV-VCKJfe6bv4UMvv+uj4LELDXsieRZFJD06Yrdyy=XxA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-08-04 10:08 ` Michal Hocko
2013-08-22 9:46 ` Fwd: " Sha Zhengju
2013-08-22 9:50 ` [PATCH 1/4] memcg: remove MEMCG_NR_FILE_MAPPED Sha Zhengju
2013-08-22 9:52 ` [PATCH 2/4] memcg: check for proper lock held in mem_cgroup_update_page_stat Sha Zhengju
2013-08-22 9:53 ` [PATCH 3/4] memcg: add per cgroup writeback pages accounting Sha Zhengju
2013-08-22 22:40 ` Andrew Morton
2013-08-23 16:11 ` Sha Zhengju
2013-08-22 9:53 ` [PATCH 4/4] memcg: Document cgroup dirty/writeback memory statistics Sha Zhengju
2013-08-04 18:51 ` [PATCH V5 5/8] memcg: add per cgroup writeback pages accounting Greg Thelen
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=CAFj3OHVXvtr5BDMrGatHZi7M9y+dh1ZKRMQZGjZmNBcg3pNQtw@mail.gmail.com \
--to=handai.szj@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=ceph-devel@vger.kernel.org \
--cc=cgroups@vger.kernel.org \
--cc=fengguang.wu@intel.com \
--cc=glommer@gmail.com \
--cc=gthelen@google.com \
--cc=handai.szj@taobao.com \
--cc=kamezawa.hiroyu@jp.fujitsu.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mhocko@suse.cz \
--cc=sage@inktank.com \
--cc=ukernel@gmail.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).