From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 75038C27C53 for ; Wed, 12 Jun 2024 15:40:40 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 024D06B00A6; Wed, 12 Jun 2024 11:40:40 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id EF0446B00A7; Wed, 12 Jun 2024 11:40:39 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DB7C56B00A8; Wed, 12 Jun 2024 11:40:39 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id B995C6B00A6 for ; Wed, 12 Jun 2024 11:40:39 -0400 (EDT) Received: from smtpin26.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 47C6D4185C for ; Wed, 12 Jun 2024 15:40:39 +0000 (UTC) X-FDA: 82222648998.26.1EA4F4D Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf21.hostedemail.com (Postfix) with ESMTP id 89D2F1C001E for ; Wed, 12 Jun 2024 15:40:37 +0000 (UTC) Authentication-Results: imf21.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=HktmaJO2; spf=pass (imf21.hostedemail.com: domain of djwong@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=djwong@kernel.org; dmarc=pass (policy=none) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1718206837; a=rsa-sha256; cv=none; b=LB1RT3LqxPdb1RPSPTGfCwF8U2u5/pzJskQ5cEve2yeY4ahoBg0j2VVVMTa+sNEOLj0Uk7 Q7JR58UzcMTP7DiP7cOW/rZNskeWB0f9MqVFI0FsAEYAIgir5yAJ3pTVh/TOIylsZE2TlL Ru/U0BGqS8R+PVzWq9+i4u1thDBaZL4= ARC-Authentication-Results: i=1; imf21.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=HktmaJO2; spf=pass (imf21.hostedemail.com: domain of djwong@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=djwong@kernel.org; dmarc=pass (policy=none) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1718206837; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=YxLrkWGC+fWSapUM1rlPinkAq+jUO5asmJYz/OCPPxo=; b=sdvK809qvsmUvhDi9jUbT57VBMc3KoDxVaDHNUSn4NIjy7SHH+iimuweg2fLnzOsB8/YpH pgfY3gg//M0M6n8hksgZ8XA2/NSY30szoeTT2t42JOOvLcG1luBaP5vaQwfIJHEgs3h2Gi YrDqEGXFfQiJtxgWpUnJpxkuLlDZeYE= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 7C50B614CD; Wed, 12 Jun 2024 15:40:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 23ECAC116B1; Wed, 12 Jun 2024 15:40:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718206836; bh=ure0E9PZwCCE0IY9IoqbKopYZ1g301DYRj00CAi1dLM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=HktmaJO2RTpRTrqfSR8FlHZ+rsRypeu+fENZHR48jiez8Y2UbDMAcpNYpiD4vQx6S pEnMbNtoaD0mpi9vtHcGOBYwnFSILO/WdcUWkJNbAb3eKh9NqZ4gF6YWetox81MYuG Ue0Bi9wLpBjv8ORF4K+YUM+90DEHh9uJvbdM0hUOs/mQoRAF6H2t8d9caCfCHC2lCq GwzYHi/OmufmuheIhYrF1nnZ558EAly0Db63nSBFO5Vs0GEQC4cancE4ySQ8TXHYNV TxxaJzEZfbxzovsteb40Wbh6rLI5k1aJGoydnLgPWTgfPHvxgfQ52Bh7wIvk95IUj9 ekLXkiHonZ/vw== Date: Wed, 12 Jun 2024 08:40:35 -0700 From: "Darrick J. Wong" To: "Pankaj Raghav (Samsung)" Cc: david@fromorbit.com, chandan.babu@oracle.com, brauner@kernel.org, akpm@linux-foundation.org, willy@infradead.org, mcgrof@kernel.org, linux-mm@kvack.org, hare@suse.de, linux-kernel@vger.kernel.org, yang@os.amperecomputing.com, Zi Yan , linux-xfs@vger.kernel.org, p.raghav@samsung.com, linux-fsdevel@vger.kernel.org, hch@lst.de, gost.dev@samsung.com, cl@os.amperecomputing.com, john.g.garry@oracle.com Subject: Re: [PATCH v7 03/11] filemap: allocate mapping_min_order folios in the page cache Message-ID: <20240612154035.GB2764752@frogsfrogsfrogs> References: <20240607145902.1137853-1-kernel@pankajraghav.com> <20240607145902.1137853-4-kernel@pankajraghav.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240607145902.1137853-4-kernel@pankajraghav.com> X-Stat-Signature: i4gpzbto3b6uumiw7jdh4iak3pqup9r5 X-Rspamd-Queue-Id: 89D2F1C001E X-Rspamd-Server: rspam04 X-Rspam-User: X-HE-Tag: 1718206837-12184 X-HE-Meta: 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 dDCSVe2I QYU6bQH4/ZYk4pDpVU8x9kOQptBkY6TeaKcpgReHnfq+ZtutnvKjADsy76iKkQB4GOMoZtmscM2bdGW1HEH02qA5k/Ec5CMLsUnB3g66/IW2FCliEK0i5y6kYmBNj3d1FpP1tB8WMrKf2HebfMsMlMXnilQZzrOoLMkwSTDYw3LDmRxJziGIvdbMyvknBMcRuNz76vSh24jUkUKD2dh6FW5/AQspNQ66+yIxW3hpZwkoLflkFDHJbkIjOlBlYBU7dqJuUDhKEFw/+FqYrYd+UP6JUzMxxb8eVCxXjdUnwb9zVLbpFwPFChYbDOrF9X40jIyyL 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: List-Subscribe: List-Unsubscribe: On Fri, Jun 07, 2024 at 02:58:54PM +0000, Pankaj Raghav (Samsung) wrote: > From: Pankaj Raghav > > filemap_create_folio() and do_read_cache_folio() were always allocating > folio of order 0. __filemap_get_folio was trying to allocate higher > order folios when fgp_flags had higher order hint set but it will default > to order 0 folio if higher order memory allocation fails. > > Supporting mapping_min_order implies that we guarantee each folio in the > page cache has at least an order of mapping_min_order. When adding new > folios to the page cache we must also ensure the index used is aligned to > the mapping_min_order as the page cache requires the index to be aligned > to the order of the folio. > > Co-developed-by: Luis Chamberlain > Signed-off-by: Luis Chamberlain > Signed-off-by: Pankaj Raghav Seems pretty straightforward, so Reviewed-by: Darrick J. Wong --D > --- > include/linux/pagemap.h | 20 ++++++++++++++++++++ > mm/filemap.c | 26 ++++++++++++++++++-------- > 2 files changed, 38 insertions(+), 8 deletions(-) > > diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h > index 228275e7049f..899b8d751768 100644 > --- a/include/linux/pagemap.h > +++ b/include/linux/pagemap.h > @@ -439,6 +439,26 @@ unsigned int mapping_min_folio_order(const struct address_space *mapping) > return (mapping->flags & AS_FOLIO_ORDER_MIN_MASK) >> AS_FOLIO_ORDER_MIN; > } > > +static inline unsigned long mapping_min_folio_nrpages(struct address_space *mapping) > +{ > + return 1UL << mapping_min_folio_order(mapping); > +} > + > +/** > + * mapping_align_start_index() - Align starting index based on the min > + * folio order of the page cache. > + * @mapping: The address_space. > + * > + * Ensure the index used is aligned to the minimum folio order when adding > + * new folios to the page cache by rounding down to the nearest minimum > + * folio number of pages. > + */ > +static inline pgoff_t mapping_align_start_index(struct address_space *mapping, > + pgoff_t index) > +{ > + return round_down(index, mapping_min_folio_nrpages(mapping)); > +} > + > /* > * Large folio support currently depends on THP. These dependencies are > * being worked on but are not yet fixed. > diff --git a/mm/filemap.c b/mm/filemap.c > index 46c7a6f59788..8bb0d2bc93c5 100644 > --- a/mm/filemap.c > +++ b/mm/filemap.c > @@ -859,6 +859,8 @@ noinline int __filemap_add_folio(struct address_space *mapping, > > VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); > VM_BUG_ON_FOLIO(folio_test_swapbacked(folio), folio); > + VM_BUG_ON_FOLIO(folio_order(folio) < mapping_min_folio_order(mapping), > + folio); > mapping_set_update(&xas, mapping); > > VM_BUG_ON_FOLIO(index & (folio_nr_pages(folio) - 1), folio); > @@ -1919,8 +1921,10 @@ struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index, > folio_wait_stable(folio); > no_page: > if (!folio && (fgp_flags & FGP_CREAT)) { > - unsigned order = FGF_GET_ORDER(fgp_flags); > + unsigned int min_order = mapping_min_folio_order(mapping); > + unsigned int order = max(min_order, FGF_GET_ORDER(fgp_flags)); > int err; > + index = mapping_align_start_index(mapping, index); > > if ((fgp_flags & FGP_WRITE) && mapping_can_writeback(mapping)) > gfp |= __GFP_WRITE; > @@ -1943,7 +1947,7 @@ struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index, > gfp_t alloc_gfp = gfp; > > err = -ENOMEM; > - if (order > 0) > + if (order > min_order) > alloc_gfp |= __GFP_NORETRY | __GFP_NOWARN; > folio = filemap_alloc_folio(alloc_gfp, order); > if (!folio) > @@ -1958,7 +1962,7 @@ struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index, > break; > folio_put(folio); > folio = NULL; > - } while (order-- > 0); > + } while (order-- > min_order); > > if (err == -EEXIST) > goto repeat; > @@ -2447,13 +2451,16 @@ static int filemap_update_page(struct kiocb *iocb, > } > > static int filemap_create_folio(struct file *file, > - struct address_space *mapping, pgoff_t index, > + struct address_space *mapping, loff_t pos, > struct folio_batch *fbatch) > { > struct folio *folio; > int error; > + unsigned int min_order = mapping_min_folio_order(mapping); > + pgoff_t index; > > - folio = filemap_alloc_folio(mapping_gfp_mask(mapping), 0); > + folio = filemap_alloc_folio(mapping_gfp_mask(mapping), > + min_order); > if (!folio) > return -ENOMEM; > > @@ -2471,6 +2478,8 @@ static int filemap_create_folio(struct file *file, > * well to keep locking rules simple. > */ > filemap_invalidate_lock_shared(mapping); > + /* index in PAGE units but aligned to min_order number of pages. */ > + index = (pos >> (PAGE_SHIFT + min_order)) << min_order; > error = filemap_add_folio(mapping, folio, index, > mapping_gfp_constraint(mapping, GFP_KERNEL)); > if (error == -EEXIST) > @@ -2531,8 +2540,7 @@ static int filemap_get_pages(struct kiocb *iocb, size_t count, > if (!folio_batch_count(fbatch)) { > if (iocb->ki_flags & (IOCB_NOWAIT | IOCB_WAITQ)) > return -EAGAIN; > - err = filemap_create_folio(filp, mapping, > - iocb->ki_pos >> PAGE_SHIFT, fbatch); > + err = filemap_create_folio(filp, mapping, iocb->ki_pos, fbatch); > if (err == AOP_TRUNCATED_PAGE) > goto retry; > return err; > @@ -3748,9 +3756,11 @@ static struct folio *do_read_cache_folio(struct address_space *mapping, > repeat: > folio = filemap_get_folio(mapping, index); > if (IS_ERR(folio)) { > - folio = filemap_alloc_folio(gfp, 0); > + folio = filemap_alloc_folio(gfp, > + mapping_min_folio_order(mapping)); > if (!folio) > return ERR_PTR(-ENOMEM); > + index = mapping_align_start_index(mapping, index); > err = filemap_add_folio(mapping, folio, index, gfp); > if (unlikely(err)) { > folio_put(folio); > -- > 2.44.1 > >