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charset=us-ascii Content-Disposition: inline In-Reply-To: <20260417-swap-table-p4-v2-9-17f5d1015428@tencent.com> X-Rspamd-Server: rspam10 X-Stat-Signature: 18a3f6u8wscpmqfurb7gyn3wrkfuog17 X-Rspam-User: X-Rspamd-Queue-Id: AA1961C0012 X-HE-Tag: 1776521006-292500 X-HE-Meta: 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 tX3XjayM mTV8n+Tx/EFe53+46NGmVPhpgJK1CImhwvSKxjHwkc3dDBoQj7UQQ7kF/ehe+T7EL+esF720ewaS2d2KRmNUPgpFJ85Wzz0/hTMRVKJetSzvKDOZtKI9BNKQJGqeRnusyDQthYRabAtELDsdG1cBQ59pO8BoR1S0iSMaJAu1XpMayIYtTbmpZzINCSQMB/f3ksA6p0oiixqU/bofHYyAF098QBQ== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > + if (IS_ENABLED(CONFIG_MEMCG) && !memcg_table) { > + swap_table_free(table); > + return -ENOMEM; > + } Hi Kairui, Nit: (Just a readability nit. purely my preference, feel free to ignore.) the checks around swap_memcg_table_alloc() reduce to two equivalent forms of the same memcg success/failure question: (!IS_ENABLED(CONFIG_MEMCG) || memcg_table) /* success */ (IS_ENABLED(CONFIG_MEMCG) && !memcg_table) /* failure */ A macro for the failure side would let the call sites read as plain positive/negative: #define SWAP_MEMCG_TABLE_ALLOC_FAILED(t) \ (IS_ENABLED(CONFIG_MEMCG) && !(t)) SWAP_MEMCG_TABLE_ALLOC_FAILED(memcg_table) /* failure */ !SWAP_MEMCG_TABLE_ALLOC_FAILED(memcg_table) /* success */ Equivalently, the same macro can be expressed by splitting on CONFIG_MEMCG. #ifdef CONFIG_MEMCG #define SWAP_MEMCG_TABLE_ALLOC_FAILED(t) (!(t)) #else #define SWAP_MEMCG_TABLE_ALLOC_FAILED(t) (0) #endif What do you think? Thanks, Youngjun Park