From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
Andrew Morton <akpm@linux-foundation.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Linux-MM <linux-mm@kvack.org>, Nitin Gupta <ngupta@vflare.org>,
Jerome Marchand <jmarchan@redhat.com>,
Ganesh Mahendran <opensource.ganesh@gmail.com>
Subject: Re: [PATCH v1 2/2] zram: remove init_lock in zram_make_request
Date: Mon, 2 Feb 2015 16:06:29 +0900 [thread overview]
Message-ID: <20150202070604.GA666@swordfish> (raw)
In-Reply-To: <20150202061812.GJ6402@blaptop>
On (02/02/15 15:18), Minchan Kim wrote:
> > a quick idea:
> > can we additionally move all bd flush and put work after zram_reset_device(zram, true)
> > and, perhaps, replace ->bd_holders with something else?
> >
> > zram_reset_device() will not return until we have active IOs, pending IOs will be
> > invalidated by ->disksize != 0.
>
> Sorry, I don't get it. Could you describe what you are concerning about active I/O?
> My concern is just race bd_holder/bd_openers and bd_holders of zram check.
> I don't think any simple solution without bd_mutex.
> If we can close the race, anything could be a solution.
> If we close the race, we should return -EBUSY if anyone is opening the zram device
> so bd_openers check would be better than bd_holders.
>
yeah, sorry. nevermind.
So, guys, how about doing it differently, in less lines of code,
hopefully. Don't move reset_store()'s work to zram_reset_device().
Instead, move
set_capacity(zram->disk, 0);
revalidate_disk(zram->disk);
out from zram_reset_device() to reset_store(). this two function are
executed only when called from reset_store() anyway. this also will let
us drop `bool reset capacity' param from zram_reset_device().
so we will do in reset_store()
mutex_lock(bdev->bd_mutex);
fsync_bdev(bdev);
zram_reset_device(zram);
set_capacity(zram->disk, 0);
mutex_unlock(&bdev->bd_mutex);
revalidate_disk(zram->disk);
bdput(bdev);
and change zram_reset_device(zram, false) call to simply zram_reset_device(zram)
in __exit zram_exit(void).
-ss
next prev parent reply other threads:[~2015-02-02 7:06 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-02-02 3:41 [PATCH v1 2/2] zram: remove init_lock in zram_make_request Minchan Kim
2015-02-02 5:59 ` Sergey Senozhatsky
2015-02-02 6:18 ` Minchan Kim
2015-02-02 7:06 ` Sergey Senozhatsky [this message]
2015-02-03 1:54 ` Sergey Senozhatsky
2015-02-03 3:02 ` Minchan Kim
2015-02-03 3:56 ` Sergey Senozhatsky
[not found] <1422432945-6764-1-git-send-email-minchan@kernel.org>
[not found] ` <1422432945-6764-2-git-send-email-minchan@kernel.org>
2015-01-28 14:56 ` Sergey Senozhatsky
2015-01-28 15:04 ` Sergey Senozhatsky
2015-01-28 23:33 ` Minchan Kim
[not found] ` <CAHqPoqKZFDSjO1pL+ixYe_m_L0nGNcu04qSNp-jd1fUixKtHnw@mail.gmail.com>
2015-01-29 2:01 ` Minchan Kim
2015-01-29 2:22 ` Sergey Senozhatsky
2015-01-29 5:28 ` Minchan Kim
2015-01-29 6:06 ` Sergey Senozhatsky
2015-01-29 6:35 ` Minchan Kim
2015-01-29 7:08 ` Sergey Senozhatsky
2015-01-30 14:41 ` Minchan Kim
2015-01-31 11:31 ` Sergey Senozhatsky
2015-02-01 14:50 ` Sergey Senozhatsky
2015-02-01 15:04 ` Sergey Senozhatsky
2015-02-02 1:43 ` Minchan Kim
2015-02-02 1:59 ` Sergey Senozhatsky
2015-02-02 2:45 ` Minchan Kim
2015-02-02 3:47 ` Sergey Senozhatsky
2015-02-02 1:30 ` Minchan Kim
2015-02-02 1:48 ` Sergey Senozhatsky
2015-02-02 2:44 ` Minchan Kim
2015-02-02 4:01 ` Sergey Senozhatsky
2015-02-02 4:28 ` Minchan Kim
2015-02-02 5:09 ` Sergey Senozhatsky
2015-02-02 5:18 ` Minchan Kim
2015-02-02 5:28 ` Sergey Senozhatsky
2015-02-02 5:10 ` Minchan Kim
2015-01-30 0:20 ` Sergey Senozhatsky
2015-01-29 13:48 ` Ganesh Mahendran
2015-01-29 15:12 ` Sergey Senozhatsky
2015-01-30 7:52 ` Ganesh Mahendran
2015-01-30 8:08 ` Sergey Senozhatsky
2015-01-31 8:50 ` Ganesh Mahendran
2015-01-31 11:07 ` Sergey Senozhatsky
2015-01-31 12:59 ` Ganesh Mahendran
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=20150202070604.GA666@swordfish \
--to=sergey.senozhatsky.work@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=jmarchan@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=minchan@kernel.org \
--cc=ngupta@vflare.org \
--cc=opensource.ganesh@gmail.com \
--cc=sergey.senozhatsky@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).