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 022972E7376 for ; Tue, 16 Jun 2026 13:54:42 +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=1781618084; cv=none; b=SfLDnAgpDdQl78kLt3m4qDe7TnLsY20aIE8s3AJNRy1uaVdLaAF6P4yqG5AuSQB7Pgi5aYAraXW/C+vhT6plmhrncebm7f0TvpmT/LXtV1VFsPwA+tZjHgWN3S6iXbgUo3d0RmdtxmgrqtaMB5zlGsxxU+3wTA3z4aPkWQDH2e8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781618084; c=relaxed/simple; bh=pTp1Wm8YDPRakNqSMg9dbXZCHmsOuyv7bmm8ybYDxms=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=WjNhV+hVSnk0vmBCltzFUADuXEESmWiWdDtW902sOPB64oRC/7yvuCZv5KW5WbullfTyiWeHiTw0K4exy7Si7a6mlI3fj4XM7d7KErDUTg5RPx0oHjUnTwYVFH4glM95gsjg5hwKqQHFz6ImOaUkKUVq5zzapgQ+XVpnbF4s4Jo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=gkxHyt5A; 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="gkxHyt5A" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3BA221F000E9; Tue, 16 Jun 2026 13:54:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1781618082; bh=Xpx08SY611J6Pr/74Bo3MmKEz6teaPqWyHRCMC9He/8=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=gkxHyt5A8udro5GTv6E1KYahAMFj5L7vsu05TMHtUr8KCgDFke79bpkrsHB20vgBP OaItxE+Pci8Wp4HIN2U/Fy5WT2F/5EcJLaIPxPSnja9GuR/wSeGOObxGLNRuzQ1NNR beR+yQLrWw2JQQT9Pd09OkioCWr9YC+1rBbi/KajsVIjXS+ZozLepELqHAjW5Uataz 6tp7Fo1CCSdI7RyOXrBlFo1X7E/UqHeYhkPrYF434pYFmzm/gIc1l9LhE6wFzj5y/n afrxyu2x0Z0js+rlSvNgcw9vHeg3MaT39BD4dSa2NiIoMdva4KQbdw5MBIv4WTiAnw 8Rle5hCEjof2A== Message-ID: <17c5f031-17e5-44c3-b572-ee224cb294cd@kernel.org> Date: Tue, 16 Jun 2026 15:54:35 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 08/12] mm/swapfile: Add batched version of folio_put_swap To: Dev Jain , akpm@linux-foundation.org, ljs@kernel.org, chrisl@kernel.org, kasong@tencent.com, hughd@google.com, liam@infradead.org Cc: riel@surriel.com, vbabka@kernel.org, harry@kernel.org, jannh@google.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, qi.zheng@linux.dev, shakeel.butt@linux.dev, baohua@kernel.org, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com, shikemeng@huaweicloud.com, nphamcs@gmail.com, bhe@redhat.com, youngjun.park@lge.com, baolin.wang@linux.alibaba.com, pfalcato@suse.de, ryan.roberts@arm.com, anshuman.khandual@arm.com References: <20260526063635.61721-1-dev.jain@arm.com> <20260526063635.61721-9-dev.jain@arm.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 5/26/26 08:36, Dev Jain wrote: > Add folio_put_swap_pages to handle a batch of consecutive pages. Note > that folio_put_swap already can handle a subset of this: nr_pages == 1 and > nr_pages == folio_nr_pages(folio). Generalize this to any nr_pages. > > Currently we have a not-so-nice logic of passing in subpage == NULL if > we mean to exercise the logic on the entire folio, and subpage != NULL if > we want to exercise the logic on only that subpage. Remove this > indirection: the caller invokes folio_put_swap_pages() if it wants to > operate on a range of pages in the folio (i.e nr_pages may be anything > between 1 till folio_nr_pages()), and invokes folio_put_swap() if it "between 1 and folio_nr_pages()" ? > wants to operate on the entire folio. > > Signed-off-by: Dev Jain > --- [...] > +++ b/mm/swap.h > @@ -208,7 +208,8 @@ extern int swap_retry_table_alloc(swp_entry_t entry, gfp_t gfp); > int folio_alloc_swap(struct folio *folio); > int folio_dup_swap_pages(struct folio *folio, struct page *page, > unsigned long nr_pages); > -void folio_put_swap(struct folio *folio, struct page *page); > +void folio_put_swap_pages(struct folio *folio, struct page *page, > + unsigned long nr_pages); Nit \tab\tab (same below) > > /* For internal use */ > extern void __swap_cluster_free_entries(struct swap_info_struct *si, > @@ -397,7 +398,8 @@ static inline int folio_dup_swap_pages(struct folio *folio, struct page *page, > return -EINVAL; > } > [...] > > swap_put_entries_cluster(si, swp_offset(entry), nr_pages, false); > } > @@ -2499,7 +2497,8 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd, > new_pte = pte_mkuffd_wp(new_pte); > setpte: > set_pte_at(vma->vm_mm, addr, pte, new_pte); > - folio_put_swap(swapcache, folio_file_page(swapcache, swp_offset(entry))); > + folio_put_swap_pages(swapcache, > + folio_file_page(swapcache, swp_offset(entry)), 1); > out: > if (pte) > pte_unmap_unlock(pte, ptl); We could consider having a simple folio_put_swap_page() helper. But maybe most of these will be converted to batching in the long run either way. Acked-by: David Hildenbrand (Arm) -- Cheers, David