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Mon, 21 Jul 2025 04:50:03 -0700 (PDT) From: wang lian To: david@redhat.com Cc: Liam.Howlett@oracle.com, akpm@linux-foundation.org, brauner@kernel.org, broonie@kernel.org, gkwang@linx-info.com, jannh@google.com, lianux.mm@gmail.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, lorenzo.stoakes@oracle.com, ludovico.zy.wu@gmail.com, p1ucky0923@gmail.com, richard.weiyang@gmail.com, ryncsn@gmail.com, shuah@kernel.org, sj@kernel.org, vbabka@suse.cz, zijing.zhang@proton.me, ziy@nvidia.com Subject: Re: [PATCH 1/2] selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));" Date: Mon, 21 Jul 2025 19:49:50 +0800 Message-ID: <20250721114950.42139-1-lianux.mm@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <42db9f05-11cc-453b-8259-39cee70f137d@redhat.com> References: <42db9f05-11cc-453b-8259-39cee70f137d@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit > On 17.07.25 15:18, wang lian wrote: > > Several mm selftests use the `asm volatile("" : "+r" (variable));` > > construct to force a read of a variable, preventing the compiler from > > optimizing away the memory access. This idiom is cryptic and duplicated > > across multiple test files. > > > > Following a suggestion from David[1], this patch refactors this > > common pattern into a FORCE_READ() macro > > > > [1] https://lore.kernel.org/lkml/4a3e0759-caa1-4cfa-bc3f-402593f1eee3@redhat.com/ > > > > Signed-off-by: wang lian > > Reviewed-by: Lorenzo Stoakes > > --- Hi David, Thank you for the review and the Acked-by tag. I appreciate it. > Acked-by: David Hildenbrand > -- > Cheers, > David / dhildenb Best regards, Wang Lian