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[2603:7000:c01:2716:97cf:7b55:44af:acd6]) by smtp.gmail.com with ESMTPSA id t23-20020a6b0917000000b007bfea3c536esm23386ioi.28.2024.02.01.09.45.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 01 Feb 2024 09:45:48 -0800 (PST) Date: Thu, 1 Feb 2024 12:45:47 -0500 From: Johannes Weiner To: Chengming Zhou Cc: Nhat Pham , Andrew Morton , Yosry Ahmed , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 1/6] mm/zswap: add more comments in shrink_memcg_cb() Message-ID: <20240201174547.GA321148@cmpxchg.org> References: <20240201-b4-zswap-invalidate-entry-v1-0-56ed496b6e55@bytedance.com> <20240201-b4-zswap-invalidate-entry-v1-1-56ed496b6e55@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: <20240201-b4-zswap-invalidate-entry-v1-1-56ed496b6e55@bytedance.com> On Thu, Feb 01, 2024 at 03:49:01PM +0000, Chengming Zhou wrote: > Add more comments in shrink_memcg_cb() to describe the deref dance > which is implemented to fix race problem between lru writeback and > swapoff, and the reason why we rotate the entry at the beginning. > > Also fix the stale comments in zswap_writeback_entry(), and add > more comments to state that we only deref the tree after we get > the swapcache reference. > > Suggested-by: Yosry Ahmed > Suggested-by: Johannes Weiner > Signed-off-by: Chengming Zhou Signed-off-by: Johannes Weiner Thanks!