From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2339E2FD5A7 for ; Fri, 4 Jul 2025 10:26:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751624804; cv=none; b=oLYnn6EL4MOb1p6IP5G6LhQzv4V2XE/+n5rRF2F/jcYlEpN7wLCkE96+Gi5XW4hBo4UVGqZzOtg3UF4FvbM78CD7ao9E1bTV7Cp0e5JKfcGpjN0kDRgoQoBiH8KfcE0tQhpdkYPWa8xGOtr+QyYfJXq6BhK+ahBVOHbWnUiYDN4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751624804; c=relaxed/simple; bh=E7QNy7Hdv+Y8vIwxIlhZiDTu7KEk+npvDBgCx+4vSO8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AjFJ4jKizMtgYgLRpPpAWdjgiHRPAeK0jW6+HlpE2a8QlZHphgBgSTQlVPf/6ee3E2Mt+7wrLAMQrOYHBbv/1BKkIyMmLBOw7EHbWZCE3zykL64MTftQRjHeoPtyoMFVPF3bNOFo2rTzgVo4rf4wEbilYBPtqLVwoJsSpLK2Y8k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=VxjtwtOB; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="VxjtwtOB" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1751624802; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=PJaNSOUY9l76maSUsyNVNOCD+/VPGSxzGfUbWAq4maw=; b=VxjtwtOB/X0IPPDaEVLwvXMHqPwLNLrRmwpUZbId9BrF/qjVx2YryyyxEg0D+cLxo53Ypk JqmkolI65KN/x4mWLQKB6xIa+n793QJJWffDIoX5gkS2VFo3Wr5NxAQcyNGzIn5VOsW540 enaT1QBFoQyBwuU+8klWU3rn3K9yUgA= Received: from mail-wm1-f69.google.com (mail-wm1-f69.google.com [209.85.128.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-434-NF3Z0XXZNeO_jAAVvEn8rg-1; Fri, 04 Jul 2025 06:26:41 -0400 X-MC-Unique: NF3Z0XXZNeO_jAAVvEn8rg-1 X-Mimecast-MFC-AGG-ID: NF3Z0XXZNeO_jAAVvEn8rg_1751624800 Received: by mail-wm1-f69.google.com with SMTP id 5b1f17b1804b1-451d7de4ae3so4257735e9.2 for ; Fri, 04 Jul 2025 03:26:40 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1751624800; x=1752229600; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=PJaNSOUY9l76maSUsyNVNOCD+/VPGSxzGfUbWAq4maw=; b=uSl9QMUoOKS19thSVmvE0fP76vylg8Nrx89dLkTlXVxP9W/bWBqH8LqItSwf58fjUV 1Holjf5zgl3X3lbdpG2GomYeXcvfy2w1040RILzc4oe3N7m6ouPRzFWLJ3G6XozoSXhP C5zfviNCvvRa8KkJ956qlpnIm/CNZwYllH/vMZmpXA9/O9JZ+OxRTnjQfFTRSqkNugfO owHrq7gquAd7qFcVrv7g5vDlsiOteFpBurWW/Zx9CE6gGsRiLbtCuY8EbY4bcqp83Pg4 SFxTu4Z64+f1m6isx/bnHuHSPXN6xolPUSuHXC++w+XL1EzSPuv5bBwC1zaFLBLAof5e iOcA== X-Forwarded-Encrypted: i=1; AJvYcCX2RqtAGsZUJlEaOonCr04ajwUwBIM9ygqxdzqrXlVcezwhO4qq6BsCTZgCQTI8ly+eUeGsTscTrMcuHbKE@vger.kernel.org X-Gm-Message-State: AOJu0Yyve6VY+pDu28tMttsHFUegqsIYy4okvfAqUsS7coju8LKqVh10 VYIfhk3aY7HqvQtfk/3GpYQ+erYMM+hMAprfPqZdtPwvAi44/J0RU0K1wn5B8OZPta7SlrKC5iK rRZKD2iwEPq2yuSnP+cm4OWOJUk5mmpWLBbRc+/IF7VzeBUTSoOrynZZnGKkhh6l8qzo= X-Gm-Gg: ASbGnctxDF8X2aFRxqLUPnTXPFwe89RjCUHola90A/nAyIFnrN/cNLtGrB/aB/jR5k1 SZMndXOQDdM3DvgfBYwFlfHA1mDcP4CbzY89EU7HJj3TDsnTt+da/NAg1O6wAIxkBH72MHP/vuS CKn58JDgpG3YiCtbPPoV/1Vod9ODx2KhMFV+FeLb4BsLgHLJc43LD3OmXdACVzkjejveY4sijWN xeC79cGG+LD543rDmqsTdO2KRJuj6euUfEYaK2h5FXUP0w+77PfFVqtYef5keNpK11mq8JgcTXD 2dlM9y+tuN9CVYvYD1W1tvl+I+2/VKiz0QmBu7aAVFFs5Hy54sjB4JUVeE7OJ5oA2LcXTgOg5q6 iJRYpFQ== X-Received: by 2002:a05:6000:24c1:b0:3a1:f564:cd9d with SMTP id ffacd0b85a97d-3b4964dbbcemr1548395f8f.36.1751624799713; Fri, 04 Jul 2025 03:26:39 -0700 (PDT) X-Google-Smtp-Source: AGHT+IG//N9DaWJpqR05PkmLCvqepmh6sjEbIjzOMJ6H89vpgrAi3DitTSNnZ5FWKxlekTJwwx1oMQ== X-Received: by 2002:a05:6000:24c1:b0:3a1:f564:cd9d with SMTP id ffacd0b85a97d-3b4964dbbcemr1548348f8f.36.1751624799228; Fri, 04 Jul 2025 03:26:39 -0700 (PDT) Received: from localhost (p200300d82f2c5500098823f9faa07232.dip0.t-ipconnect.de. [2003:d8:2f2c:5500:988:23f9:faa0:7232]) by smtp.gmail.com with UTF8SMTPSA id 5b1f17b1804b1-454b1628d6csm23008015e9.10.2025.07.04.03.26.37 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 04 Jul 2025 03:26:38 -0700 (PDT) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-doc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, virtualization@lists.linux.dev, linux-fsdevel@vger.kernel.org, David Hildenbrand , Andrew Morton , Jonathan Corbet , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Jerrin Shaji George , Arnd Bergmann , Greg Kroah-Hartman , "Michael S. Tsirkin" , Jason Wang , Xuan Zhuo , =?UTF-8?q?Eugenio=20P=C3=A9rez?= , Alexander Viro , Christian Brauner , Jan Kara , Zi Yan , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Gregory Price , Ying Huang , Alistair Popple , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , "Matthew Wilcox (Oracle)" , Minchan Kim , Sergey Senozhatsky , Brendan Jackman , Johannes Weiner , Jason Gunthorpe , John Hubbard , Peter Xu , Xu Xin , Chengming Zhou , Miaohe Lin , Naoya Horiguchi , Oscar Salvador , Rik van Riel , Harry Yoo , Qi Zheng , Shakeel Butt Subject: [PATCH v2 25/29] mm: simplify folio_expected_ref_count() Date: Fri, 4 Jul 2025 12:25:19 +0200 Message-ID: <20250704102524.326966-26-david@redhat.com> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250704102524.326966-1-david@redhat.com> References: <20250704102524.326966-1-david@redhat.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Now that PAGE_MAPPING_MOVABLE is gone, we can simplify and rely on the folio_test_anon() test only. ... but staring at the users, this function should never even have been called on movable_ops pages. E.g., * __buffer_migrate_folio() does not make sense for them * folio_migrate_mapping() does not make sense for them * migrate_huge_page_move_mapping() does not make sense for them * __migrate_folio() does not make sense for them * ... and khugepaged should never stumble over them Let's simply refuse typed pages (which includes slab) except hugetlb, and WARN. Reviewed-by: Zi Yan Reviewed-by: Lorenzo Stoakes Reviewed-by: Harry Yoo Signed-off-by: David Hildenbrand --- include/linux/mm.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index ef40f68c1183d..805108d7bbc31 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2167,13 +2167,13 @@ static inline int folio_expected_ref_count(const struct folio *folio) const int order = folio_order(folio); int ref_count = 0; - if (WARN_ON_ONCE(folio_test_slab(folio))) + if (WARN_ON_ONCE(page_has_type(&folio->page) && !folio_test_hugetlb(folio))) return 0; if (folio_test_anon(folio)) { /* One reference per page from the swapcache. */ ref_count += folio_test_swapcache(folio) << order; - } else if (!((unsigned long)folio->mapping & PAGE_MAPPING_FLAGS)) { + } else { /* One reference per page from the pagecache. */ ref_count += !!folio->mapping << order; /* One reference from PG_private. */ -- 2.49.0