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Thu, 17 Apr 2025 07:58:27 -0700 (PDT) Date: Thu, 17 Apr 2025 10:58:26 -0400 From: Johannes Weiner To: Muchun Song Cc: mhocko@kernel.org, roman.gushchin@linux.dev, shakeel.butt@linux.dev, muchun.song@linux.dev, akpm@linux-foundation.org, david@fromorbit.com, zhengqi.arch@bytedance.com, yosry.ahmed@linux.dev, nphamcs@gmail.com, chengming.zhou@linux.dev, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, hamzamahfooz@linux.microsoft.com, apais@linux.microsoft.com Subject: Re: [PATCH RFC 06/28] mm: thp: introduce folio_split_queue_lock and its variants Message-ID: <20250417145826.GI780688@cmpxchg.org> References: <20250415024532.26632-1-songmuchun@bytedance.com> <20250415024532.26632-7-songmuchun@bytedance.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: <20250415024532.26632-7-songmuchun@bytedance.com> On Tue, Apr 15, 2025 at 10:45:10AM +0800, Muchun Song wrote: > In future memcg removal, the binding between a folio and a memcg may change, > making the split lock within the memcg unstable when held. > > A new approach is required to reparent the split queue to its parent. This > patch starts introducing a unified way to acquire the split lock for future > work. > > It's a code-only refactoring with no functional changes. > > Signed-off-by: Muchun Song Acked-by: Johannes Weiner