From: Hao Peng <flyingpenghao@gmail.com>
To: Miklos Szeredi <miklos@szeredi.hu>
Cc: linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] fuse: Use kmap_local_page()
Date: Fri, 20 Aug 2021 09:48:42 +0800 [thread overview]
Message-ID: <CAPm50a+0UK-CvBHZXxjxXpGns3AXpewWyviPyTaq8oQLHcs99Q@mail.gmail.com> (raw)
In-Reply-To: <CAJfpeguDzHO9rx4eVRi4Lvjj0O9-oT8SEN7JAfWtsNj-6M_YAA@mail.gmail.com>
>On Tue, Aug 17, 2021 at 11:42 PM Miklos Szeredi <miklos@szeredi.hu> wrote:
>
> On Tue, 17 Aug 2021 at 05:17, Hao Peng <flyingpenghao@gmail.com> wrote:
> >
> > kmap_local_page() is enough.
>
> This explanation is not enough for me to understand the patch. Please
> describe in more detail.
>
Due to the introduction of kmap_local_*, the storage of slots used for
short-term mapping has
changed from per-CPU to per-thread. kmap_atomic() disable preemption,
while kmap_local_*()
only disable migration.
There is no need to disable preemption in several kamp_atomic places
used in fuse.
The detailed introduction of kmap_local_*d can be found here:
https://lwn.net/Articles/836144/
Thanks.
> Thanks,
> Miklos
next prev parent reply other threads:[~2021-08-20 1:49 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CAPm50aLNUNGo94u1yVKSJwy3rehRP84ha8YmbOdMyehFeVah0w@mail.gmail.com>
2021-08-17 15:41 ` [PATCH] fuse: Use kmap_local_page() Miklos Szeredi
2021-08-20 1:48 ` Hao Peng [this message]
[not found] ` <CAPm50aLXQC_Q+fEPsJaUJjn7ahHV57FM1vCOVwJpFfnghXXbzw@mail.gmail.com>
2021-09-07 15:04 ` Miklos Szeredi
2021-09-08 8:38 Peng Hao
2021-09-08 8:56 ` Miklos Szeredi
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=CAPm50a+0UK-CvBHZXxjxXpGns3AXpewWyviPyTaq8oQLHcs99Q@mail.gmail.com \
--to=flyingpenghao@gmail.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=miklos@szeredi.hu \
/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).