From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 27C7A39EF23; Fri, 27 Mar 2026 12:50:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774615836; cv=none; b=qER/rxGvdeZmdeXLQfRgfWRco09BfSnXq2cR6ss+cd9FWkSH6J99UZLjiCadoeclftaDLqjymRJnkd2/vGEN7KW2o4c2OFPA1matR5ON3Pbc4J56w3C+X0Ca5CHPN+0pKAB5yLkwlrsIKvDmvO4ofeoS49b7CDGlmJE+Z8w/nUY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774615836; c=relaxed/simple; bh=7TtvxfvBKonF+oVtDcunkjFuZJVVhgHI8FyFmO9gAyY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=NzUx5PYB+NEfGDBvwZ6tPwXU6Mj2agjJ5UDbPWjskMB7A3R5B5kJMOw/hDxFAy5C6MJS3fH1ybwqlLoPKBUuLN695gLiBJN+2gSUTDVkit0hrwUoMLTLn1UdWKpmOzr6XM8wDl3f4vo+w/MyHrSiJQT6m8yky1i6x7UZhxjZx0c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=dbrt/V4U; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="dbrt/V4U" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3774DC19423; Fri, 27 Mar 2026 12:50:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774615835; bh=7TtvxfvBKonF+oVtDcunkjFuZJVVhgHI8FyFmO9gAyY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=dbrt/V4U3RhDsEEVQice4TAK4sJiHyb4Calj2k3bm3O2B2llHOuxX9IC0SP/Ooufj JKx+gTxPfFON6p/vKpJsGfUm7cJLFZFJf5/wmGK4M5PmC+rL0K2N5sSwFvcU/9lYRe nfsyXZ91doAm0vVLg3oO3pP0FG6a21YhfdVKVCh5Iy9pYCpPb8QbfeD40nECYwrfuZ EGmtmUxAUOUPOOdjKLVDzABtHSkbofi91uoQUVuMOarXnIoyaZ6g1qxjdzE8d6/APx t3jBYudMko9aT53uZlcaIA+tqoETqvMZsu/56Nwx56rIg6ijstSfa6CPmDX0mnlhHP tQouBAQ0ri3rQ== Date: Fri, 27 Mar 2026 12:50:33 +0000 From: "Lorenzo Stoakes (Oracle)" To: Zi Yan Cc: "Matthew Wilcox (Oracle)" , Song Liu , Chris Mason , David Sterba , Alexander Viro , Christian Brauner , Jan Kara , Andrew Morton , David Hildenbrand , Baolin Wang , "Liam R. Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Shuah Khan , linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org Subject: Re: [PATCH v1 06/10] mm/huge_memory: remove folio split check for READ_ONLY_THP_FOR_FS Message-ID: References: <20260327014255.2058916-1-ziy@nvidia.com> <20260327014255.2058916-7-ziy@nvidia.com> Precedence: bulk X-Mailing-List: linux-btrfs@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: <20260327014255.2058916-7-ziy@nvidia.com> On Thu, Mar 26, 2026 at 09:42:51PM -0400, Zi Yan wrote: > Without READ_ONLY_THP_FOR_FS, large file-backed folios cannot be created by > a FS without large folio support. The check is no longer needed. > > Signed-off-by: Zi Yan Seems legitimate, so: Reviewed-by: Lorenzo Stoakes (Oracle) > --- > mm/huge_memory.c | 22 ---------------------- > 1 file changed, 22 deletions(-) > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index 1da1467328a3..30eddcbf86f1 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -3732,28 +3732,6 @@ int folio_check_splittable(struct folio *folio, unsigned int new_order, > /* order-1 is not supported for anonymous THP. */ > if (new_order == 1) > return -EINVAL; > - } else if (split_type == SPLIT_TYPE_NON_UNIFORM || new_order) { > - if (IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS) && > - !mapping_large_folio_support(folio->mapping)) { > - /* > - * We can always split a folio down to a single page > - * (new_order == 0) uniformly. > - * > - * For any other scenario > - * a) uniform split targeting a large folio > - * (new_order > 0) > - * b) any non-uniform split > - * we must confirm that the file system supports large > - * folios. > - * > - * Note that we might still have THPs in such > - * mappings, which is created from khugepaged when > - * CONFIG_READ_ONLY_THP_FOR_FS is enabled. But in that > - * case, the mapping does not actually support large > - * folios properly. > - */ > - return -EINVAL; > - } > } > > /* > -- > 2.43.0 >