From: Andrew Morton <akpm@linux-foundation.org>
To: Matthew Wilcox <willy@infradead.org>
Cc: Christoph Hellwig <hch@infradead.org>,
Manjong Lee <mj0123.lee@samsung.com>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org,
seunghwan.hyun@samsung.com, sookwan7.kim@samsung.com,
nanich.lee@samsung.com, yt0928.kim@samsung.com,
junho89.kim@samsung.com, jisoo2146.oh@samsung.com
Subject: Re: [PATCH 1/1] mm: bdi: Initialize bdi_min_ratio when bdi unregister
Date: Thu, 21 Oct 2021 19:45:30 -0700 [thread overview]
Message-ID: <20211021194530.1fabf4fa45cfe3bee6598484@linux-foundation.org> (raw)
In-Reply-To: <YXFWmo9v65kJWVWC@casper.infradead.org>
On Thu, 21 Oct 2021 13:01:30 +0100 Matthew Wilcox <willy@infradead.org> wrote:
> On Thu, Oct 21, 2021 at 04:16:52AM -0700, Christoph Hellwig wrote:
> > On Fri, Oct 22, 2021 at 01:19:43AM +0900, Manjong Lee wrote:
> > > Because when sdcard is removed, bdi_min_ratio value will remain.
> > > Currently, the only way to reset bdi_ min_ratio is to reboot.
> >
> > But bdis that are unregistered are never re-registered. What is
> > the problem you're trying to solve?
>
> The global bdi_min_ratio needs to be adjusted. See
> bdi_set_min_ratio() in mm/page-writeback.c.
I added cc:stable to this and tweaked the comment & coding style a bit:
--- a/mm/backing-dev.c~mm-bdi-initialize-bdi_min_ratio-when-bdi-unregister-fix
+++ a/mm/backing-dev.c
@@ -947,10 +947,12 @@ void bdi_unregister(struct backing_dev_i
wb_shutdown(&bdi->wb);
cgwb_bdi_unregister(bdi);
- /* if min ratio doesn't 0, it has to set 0 before unregister */
- if (bdi->min_ratio) {
+ /*
+ * If this BDI's min ratio has been set, use bdi_set_min_ratio() to
+ * update the global bdi_min_ratio.
+ */
+ if (bdi->min_ratio)
bdi_set_min_ratio(bdi, 0);
- }
if (bdi->dev) {
bdi_debug_unregister(bdi);
_
next prev parent reply other threads:[~2021-10-22 2:45 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20211021072307epcas1p4aa4388c13e71a66e3e1d5f7ee68b5a7f@epcas1p4.samsung.com>
2021-10-21 16:19 ` [PATCH 1/1] mm: bdi: Initialize bdi_min_ratio when bdi unregister Manjong Lee
2021-10-21 11:16 ` Christoph Hellwig
2021-10-21 12:01 ` Matthew Wilcox
2021-10-22 2:45 ` Andrew Morton [this message]
2021-10-22 2:58 ` Matthew Wilcox
[not found] ` <CGME20211022043310epcas1p22952e8fa3eb3675717badae9a3e1223e@epcas1p2.samsung.com>
2021-10-22 13:39 ` Manjong Lee
2021-12-10 21:35 ` Peter Zijlstra
2021-12-10 21:36 ` Peter Zijlstra
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=20211021194530.1fabf4fa45cfe3bee6598484@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=hch@infradead.org \
--cc=jisoo2146.oh@samsung.com \
--cc=junho89.kim@samsung.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mj0123.lee@samsung.com \
--cc=nanich.lee@samsung.com \
--cc=seunghwan.hyun@samsung.com \
--cc=sookwan7.kim@samsung.com \
--cc=willy@infradead.org \
--cc=yt0928.kim@samsung.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).