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Tue, 08 Aug 2023 01:46:35 -0700 (PDT) Received: from localhost.localdomain ([43.132.141.9]) by smtp.gmail.com with ESMTPSA id kb14-20020a170903338e00b001bbbc655ca1sm8383487plb.219.2023.08.08.01.46.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 08 Aug 2023 01:46:35 -0700 (PDT) From: alexjlzheng@gmail.com X-Google-Original-From: alexjlzheng@tencent.com To: akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Jinliang Zheng Subject: [PATCH] writeback: remove redundant checks for root memcg Date: Tue, 8 Aug 2023 16:44:32 +0800 Message-Id: <20230808084431.1632934-1-alexjlzheng@tencent.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 X-Rspamd-Queue-Id: 1144A4000C X-Rspam-User: X-Stat-Signature: gng8kww3a4u7nroak1rktnufcfxkt46i X-Rspamd-Server: rspam01 X-HE-Tag: 1691484396-878909 X-HE-Meta: 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 PdJYILVw I2G5rxpsJVFIyC7LiolzJUP4ug9Uu+ec0PUHDBjJ5NQhvcoRxZBMVxcaV9r9eFZsVAZep1+4lSKs40Pn9S8mdheOV8FqxjE5MTXrc+VLkRwiIzs9qlu1y4hQJDrxsnZ2V7zp2wUoZUjvOmUeFS7Z4GArlnQXLAdGpM8YrfybBgqZPx/aof7j25ejdCLdIvIQIB8/tIQPG/9EmtXvDEscTbj1bwAVGnWn5RIYp9gJU4KOXEwIbXxuePFcJPFEjcmRuuCa8etBAYuz508zv3HtDadaQ5pqI8W8RMxPgkrwP3/8A9bDx+frNXCADZCw6isK5DjAV21pn3lB0+mvWoUI4KaDy2AgDB+BAuSUcT86moU/RXJf9As6wHSFbs2ZgpPGd2wf1y9FIyrp9OeD8HVOUqye7/ErgOORvoQwXGc0b60Cx57IqijYqN7Jc06toWY2ga06D X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Jinliang Zheng The check for root memcg will be done in wb_get_lookup(), so remove the redundant one to simplify the code. Signed-off-by: Jinliang Zheng --- mm/backing-dev.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/mm/backing-dev.c b/mm/backing-dev.c index 3ffc3cfa7a14..9076f3ad39de 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -733,9 +733,6 @@ struct bdi_writeback *wb_get_create(struct backing_dev_info *bdi, might_alloc(gfp); - if (!memcg_css->parent) - return &bdi->wb; - do { wb = wb_get_lookup(bdi, memcg_css); } while (!wb && !cgwb_create(bdi, memcg_css, gfp));