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[141.239.149.160]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-2ccf7b2c5edsm7366670a91.3.2024.07.22.11.15.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 22 Jul 2024 11:15:41 -0700 (PDT) Sender: Tejun Heo Date: Mon, 22 Jul 2024 08:15:40 -1000 From: Tejun Heo To: Boqun Feng Cc: kernel test robot , Suren Baghdasaryan , oe-lkp@lists.linux.dev, lkp@intel.com, linux-kernel@vger.kernel.org, Andrew Morton , Kent Overstreet , Kees Cook , Alexander Viro , Alex Gaynor , Alice Ryhl , Andreas Hindborg , Benno Lossin , =?iso-8859-1?Q?Bj=F6rn?= Roy Baron , Christoph Lameter , Dennis Zhou , Gary Guo , Miguel Ojeda , Pasha Tatashin , Peter Zijlstra , Vlastimil Babka , Wedson Almeida Filho , linux-mm@kvack.org, lkmm@lists.linux.dev Subject: Re: [linus:master] [mm] 24e44cc22a: BUG:KCSAN:data-race_in_pcpu_alloc_noprof/pcpu_block_update_hint_alloc Message-ID: References: <202407191651.f24e499d-oliver.sang@intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Hello, On Mon, Jul 22, 2024 at 11:03:00AM -0700, Boqun Feng wrote: ... > For READ/WRITE_ONCE(), we will need to replace all write accesses and > all out-of-lock read accesses to pcpu_nr_empty_pop_pages, like below. > It's better in the sense that it doesn't rely on compiler behaviors on > data races, not sure about the performance impact though. The patch looks great and I doubt this would impact performance in any noticeable way. Thanks. -- tejun