linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: Catalin Marinas <catalin.marinas@arm.com>
To: Guanghui Feng <guanghuifeng@linux.alibaba.com>
Cc: will@kernel.org, maz@kernel.org, qperret@google.com,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, baolin.wang@linux.alibaba.com,
	zhuo.song@linux.alibaba.com, zhangliguang@linux.alibaba.com
Subject: Re: [PATCH] arm64: clear_page: use stnp non-temporal instruction for performance optimizing
Date: Tue, 16 Nov 2021 18:17:12 +0000	[thread overview]
Message-ID: <YZP1qMj4dWCbDrN6@arm.com> (raw)
In-Reply-To: <1637075294-30747-1-git-send-email-guanghuifeng@linux.alibaba.com>

On Tue, Nov 16, 2021 at 11:08:14PM +0800, Guanghui Feng wrote:
> When clear page mem, there is no need to alloc cache for storing these
> mem value.

I theory, DC ZVA is supposed to trigger write streaming mode and all
writes go directly to memory avoiding cache allocation.

> And the copy_page.S have used stnp instruction for optimizing.
> So I rewrite the clear_page.S with stnp. At the same time, I have tested it
> with stnp instruction which will get about twice the performance improvement.

On which CPU implementation? Is the same improvement seen on a wider
range of CPUs?

-- 
Catalin

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2021-11-16 18:18 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-11-16 15:08 [PATCH] arm64: clear_page: use stnp non-temporal instruction for performance optimizing Guanghui Feng
2021-11-16 18:17 ` Catalin Marinas [this message]
2021-11-16 23:12 ` Robin Murphy

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=YZP1qMj4dWCbDrN6@arm.com \
    --to=catalin.marinas@arm.com \
    --cc=baolin.wang@linux.alibaba.com \
    --cc=guanghuifeng@linux.alibaba.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=maz@kernel.org \
    --cc=qperret@google.com \
    --cc=will@kernel.org \
    --cc=zhangliguang@linux.alibaba.com \
    --cc=zhuo.song@linux.alibaba.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).