From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 636BF2FFF90 for ; Mon, 10 Aug 2026 12:55:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786366528; cv=none; b=CTR4uQfknD1M0U54GzJrKqxXgMiMwHBj+Tc5AFjngN7cBqKToOKMyr5oNX2ZOQGzabTOsNskZIFfxtr25j1+lxZIovuTvXsxcpK8i9QHFp0RR5obLvaPSb+dWBu2MFKIwcplGr75Q91Yv9e29SE5DxADga2Gb81cwTKJS8hF1NQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786366528; c=relaxed/simple; bh=PN5oO/vuMzABxSY/381UcI3wYI9qkw0HJxSU25Zk57M=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=C2AkRHQ2ZvlYzSwvyH/S3ynRkb+AcenlmxpurrLr1ZolXkt99Vg14x3mX6G36xgzbC4NrdDvpJ839JSjvET8gcDkeorSIoEoK0vS7j18ClWZFtTn9NWQB0sIYCXd/dvhvwY+lqbRPq7fnIHGUcsyNFT4w1sLGTAoAszkkq5gfwk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=YWXhF5g4; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="YWXhF5g4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 585561F000E9; Mon, 10 Aug 2026 12:55:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786366527; bh=q3fbdyvCGVnrDuoB4RN/w4ZZdW26Al8oLsjQqGypFMs=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=YWXhF5g4j1HNEuU2xUlOoC0+xwHqbDkrFN4BAhSr4rCpMTZw0Y852TJrOp8Cibh/Z NqTcD6/AiIBvgB9Wh4lWhGwogYj7Wqi4bCZjwu3a2GCZF1MuYUGr7X1NZNvniErEnp j0H8t1sbfQP3yhRLBcxkw/kOSK8z9UokIcgm0NESHCk9lSFtjLjSTtP6JX7vQJvCOP ZbKOvSGfoK2j3E47ZDk6KHjXdhqoit6TA2CE3qqc3hNYDUNymCJ8zPVdhxEXDUx4Cm 9A4pkl+QuIqBMqfzr4+1/YcBsbgR2pyGOe4XS1ER8/2c5JuZjokcmOdza9a/V7xX0d M+FlldjqDDJ9Q== Date: Mon, 10 Aug 2026 13:55:06 +0100 From: "Lorenzo Stoakes (ARM)" To: Tal Zussman Cc: Andrew Morton , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , Barry Song , Youngjun Park , David Hildenbrand , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Matthew Wilcox , Christoph Hellwig , Johannes Weiner , Yosry Ahmed , Chengming Zhou , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/6] mm/page_io: use swap entries directly in zeromap helpers Message-ID: References: <20260806-b4-page_io-folios-v1-0-0899bac3b826@columbia.edu> <20260806-b4-page_io-folios-v1-3-0899bac3b826@columbia.edu> Precedence: bulk X-Mailing-List: linux-kernel@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: <20260806-b4-page_io-folios-v1-3-0899bac3b826@columbia.edu> On Thu, Aug 06, 2026 at 06:55:35PM -0400, Tal Zussman wrote: > Increment swp_entry_t::val directly instead of recomputing each entry > with page_swap_entry(). This removes the last struct page usage in > page_io.c and saves one call to compound_head() per page. > > Signed-off-by: Tal Zussman Lord I just looked at page_swap_entry() and... yeah. This is an improvement thanks :) I haven't looked at the rest of the series so maybe you already did it but I wonder if we could remove it altogether? Should we rename page_io.c to folio_io.c now? :P Anyway LGTM so: Reviewed-by: Lorenzo Stoakes (ARM) > --- > mm/page_io.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/mm/page_io.c b/mm/page_io.c > index 43b4383a4729..c6d0949b3f1e 100644 > --- a/mm/page_io.c > +++ b/mm/page_io.c > @@ -159,7 +159,7 @@ static void swap_zeromap_folio_set(struct folio *folio) > struct obj_cgroup *objcg = get_obj_cgroup_from_folio(folio); > int nr_pages = folio_nr_pages(folio); > struct swap_cluster_info *ci; > - swp_entry_t entry; > + swp_entry_t entry = folio->swap; > unsigned int i; > > VM_WARN_ON_ONCE_FOLIO(!folio_test_swapcache(folio), folio); > @@ -167,8 +167,8 @@ static void swap_zeromap_folio_set(struct folio *folio) > > ci = swap_cluster_get_and_lock(folio); > for (i = 0; i < folio_nr_pages(folio); i++) { > - entry = page_swap_entry(folio_page(folio, i)); > __swap_table_set_zero(ci, swp_cluster_offset(entry)); > + entry.val++; > } > swap_cluster_unlock(ci); > > @@ -182,7 +182,7 @@ static void swap_zeromap_folio_set(struct folio *folio) > static void swap_zeromap_folio_clear(struct folio *folio) > { > struct swap_cluster_info *ci; > - swp_entry_t entry; > + swp_entry_t entry = folio->swap; > unsigned int i; > > VM_WARN_ON_ONCE_FOLIO(!folio_test_swapcache(folio), folio); > @@ -190,8 +190,8 @@ static void swap_zeromap_folio_clear(struct folio *folio) > > ci = swap_cluster_get_and_lock(folio); > for (i = 0; i < folio_nr_pages(folio); i++) { > - entry = page_swap_entry(folio_page(folio, i)); > __swap_table_clear_zero(ci, swp_cluster_offset(entry)); > + entry.val++; > } > swap_cluster_unlock(ci); > } > > -- > 2.39.5 > -- Cheers, Lorenzo