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 5E980FC6168 for ; Fri, 13 Sep 2024 17:13:43 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9D6F56B00BF; Fri, 13 Sep 2024 13:13:42 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9878D6B00C1; Fri, 13 Sep 2024 13:13:42 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 84F1F6B00C2; Fri, 13 Sep 2024 13:13:42 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 638146B00BF for ; Fri, 13 Sep 2024 13:13:42 -0400 (EDT) Received: from smtpin19.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id CCC5F1C4FF0 for ; 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charset=us-ascii Content-Disposition: inline In-Reply-To: <20240912204129.1432995-1-yang@os.amperecomputing.com> X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 1E7981C0003 X-Stat-Signature: x6at7dxhbea6wxn9w8zwaffwg1z7gjbc X-Rspam-User: X-HE-Tag: 1726247619-880485 X-HE-Meta: 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 qtaWr9XO cpD39+kiCiKfeFpgcE/iUFqqxZsOxsQ5aBcWBaSEoC5e3vu+rt1fmNdFNIBiTwLHDWT5XZ6eGBFlzJpRZg4uZTo95MxmCMPduC5p/NRzT7UuhAQCl22BX1VMCT2xEtKUwdCqYKFPKDnvIMYdsvHmeIncNUnn1odYnnW6oGhePYB5a2FgZ4tx1OqY2hfDFO9diy9SIXB5oTnHLC6uZnAXT8Iml2FQcadp3pSUIik2A9BCnV3xJIWAD7T0sb5pcLwm0EacyjmP8m3P5ze9RgGBFKX9/9zJcJ0wrQTGHfwoYBU/dQOq7DeVgn9vGphQmQUNGDey/qIx5EHbqgaYxAakpOa+ErXH3WkZbf0s2 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 Thu, Sep 12, 2024 at 01:41:28PM -0700, Yang Shi wrote: > diff --git a/arch/arm64/mm/copypage.c b/arch/arm64/mm/copypage.c > index a7bb20055ce0..c8687ccc2633 100644 > --- a/arch/arm64/mm/copypage.c > +++ b/arch/arm64/mm/copypage.c > @@ -18,17 +18,41 @@ void copy_highpage(struct page *to, struct page *from) > { > void *kto = page_address(to); > void *kfrom = page_address(from); > + struct folio *src = page_folio(from); > + struct folio *dst = page_folio(to); > + unsigned int i, nr_pages; > > copy_page(kto, kfrom); > > if (kasan_hw_tags_enabled()) > page_kasan_tag_reset(to); > > - if (system_supports_mte() && page_mte_tagged(from)) { > - /* It's a new page, shouldn't have been tagged yet */ > - WARN_ON_ONCE(!try_page_mte_tagging(to)); > - mte_copy_page_tags(kto, kfrom); > - set_page_mte_tagged(to); > + if (system_supports_mte()) { > + if (folio_test_hugetlb(src) && > + folio_test_hugetlb_mte_tagged(src)) { > + if (!try_folio_hugetlb_mte_tagging(dst)) > + return; > + > + /* > + * Populate tags for all subpages. > + * > + * Don't assume the first page is head page since > + * huge page copy may start from any subpage. > + */ > + nr_pages = folio_nr_pages(src); > + for (i = 0; i < nr_pages; i++) { > + kfrom = page_address(folio_page(src, i)); > + kto = page_address(folio_page(dst, i)); > + mte_copy_page_tags(kto, kfrom); > + } > + folio_set_hugetlb_mte_tagged(dst); > + } else if (page_mte_tagged(from)) { > + /* It's a new page, shouldn't have been tagged yet */ > + WARN_ON_ONCE(!try_page_mte_tagging(to)); > + > + mte_copy_page_tags(kto, kfrom); > + set_page_mte_tagged(to); > + } > } > } A nitpick here: I don't like that much indentation, so just do an early return if !system_supports_mte() in this function. Otherwise the patch looks fine to me. I agree with David's point on an earlier version of this patch, the naming of these functions isn't great. So, as per David's suggestion (at least for the first two): folio_test_hugetlb_mte_tagged() folio_set_hugetlb_mte_tagged() folio_try_hugetlb_mte_tagging() As for "try" vs "test_and_set_.*_lock", the original name was picked to mimic spin_trylock() since this function is waiting/spinning. It's not great but the alternative naming is closer to test_and_set_bit_lock(). This has different behaviour, it only sets a bit with acquire semantics, no waiting/spinning. -- Catalin