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Shutemov" To: yanfei.xu@windriver.com Cc: akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] khugepaged: Raplace barrier() with READ_ONCE() for a selective variable Message-ID: <20210323102101.tvlgbijpy37hclgj@box> References: <20210323092730.247583-1-yanfei.xu@windriver.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210323092730.247583-1-yanfei.xu@windriver.com> X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: F222B80192DD X-Stat-Signature: j6ynxw7j6j57pbjspkqx55k49mtzxqii Received-SPF: none (shutemov.name>: No applicable sender policy available) receiver=imf16; identity=mailfrom; envelope-from=""; helo=mail-lf1-f48.google.com; client-ip=209.85.167.48 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616494854-690789 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Mar 23, 2021 at 05:27:30PM +0800, yanfei.xu@windriver.com wrote: > From: Yanfei Xu > > READ_ONCE() is more selective and lightweight. It is more appropriate that > using a READ_ONCE() for the certain variable to prevent the compiler from > reordering. > > Signed-off-by: Yanfei Xu Acked-by: Kirill A. Shutemov -- Kirill A. Shutemov