From patchwork Thu Feb 15 10:31:49 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 13557852 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 434F5C48BEB for ; Thu, 15 Feb 2024 10:32:30 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D3E628D0014; Thu, 15 Feb 2024 05:32:29 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id C9E9A8D0001; Thu, 15 Feb 2024 05:32:29 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BB4668D0014; Thu, 15 Feb 2024 05:32:29 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id AAE408D0001 for ; Thu, 15 Feb 2024 05:32:29 -0500 (EST) Received: from smtpin05.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 7B80D120F31 for ; Thu, 15 Feb 2024 10:32:29 +0000 (UTC) X-FDA: 81793674018.05.AF3E497 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf04.hostedemail.com (Postfix) with ESMTP id BF4F44000E for ; Thu, 15 Feb 2024 10:32:27 +0000 (UTC) Authentication-Results: imf04.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf04.hostedemail.com: domain of ryan.roberts@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=ryan.roberts@arm.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1707993148; a=rsa-sha256; cv=none; b=ht8fmrq9N5wvgEHOPKGH3UtZFvCgtJFPEeNZPL7WOKI8uIYlu5HivNcB7ZTPp5CnoMFc7r v4rJAIxlraQnIsG3vVddAzPlJO1oqhsNdUZRv4u5i6XqUvW0W6FLZZxknSgi+afG0S69fE 0MW4ar9vo0ECVs2GJajLn9Bh8w7XWqM= ARC-Authentication-Results: i=1; imf04.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf04.hostedemail.com: domain of ryan.roberts@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=ryan.roberts@arm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1707993148; 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-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=iYGxY8gKE5MXdRT9yHHw6Vo1X8bbi/EsI1w4KtEcUbM=; b=7wH84Uo1/iu+Ep+3hcX1wwinPJin6g+fy51G2/ONvTq4BMx44y6/MA4K1nGc16NA0eXZG9 4cBak/pnlSBiMvnic2AQlI8a2pMsWS8J8GH0us9QfKK6d43A9B5RVl3wTOjDIbqVAM0KtS B+WYUs1W+k1yAyBEqz1iOzwdr/8ts0E= Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A52231480; Thu, 15 Feb 2024 02:33:07 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9BFF83F7B4; Thu, 15 Feb 2024 02:32:23 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Ard Biesheuvel , Marc Zyngier , James Morse , Andrey Ryabinin , Andrew Morton , Matthew Wilcox , Mark Rutland , David Hildenbrand , Kefeng Wang , John Hubbard , Zi Yan , Barry Song <21cnbao@gmail.com>, Alistair Popple , Yang Shi , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, x86@kernel.org, linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v6 02/18] mm: thp: Batch-collapse PMD with set_ptes() Date: Thu, 15 Feb 2024 10:31:49 +0000 Message-Id: <20240215103205.2607016-3-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240215103205.2607016-1-ryan.roberts@arm.com> References: <20240215103205.2607016-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: BF4F44000E X-Stat-Signature: gp8ak3pbe6mfois31zgo6z66tbb457ae X-Rspam-User: X-HE-Tag: 1707993147-876281 X-HE-Meta: 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 N8xewGSx 07na56FSqlcVxaBzsmS4PECAAQs6lyvYFpKOg3H52hV7H/lD5auenuAlwyw7Lq3a1ISdYdjujOLxisoJpKEK4IDFUoEh2/qtnCJhtio2nqrWG4ajl5HEuXhuVAmH1bKupUaKcLbGzZyZNkiRYtBLHVGNyxBh4mHAES+79dBtVSjIZNDthryL/qCoc1K9y+o3RGGeSBtVbPKUy1T4QFuLbJx14xlIgK/2GWnVWQHMlEYiL10RNFNP860afllLA+FfJu5utxEgkBQA1cKqBeSWS5/Kak5mu4wPSoXiOPs/9cYdsnbQ= 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: Refactor __split_huge_pmd_locked() so that a present PMD can be collapsed to PTEs in a single batch using set_ptes(). This should improve performance a little bit, but the real motivation is to remove the need for the arm64 backend to have to fold the contpte entries. Instead, since the ptes are set as a batch, the contpte blocks can be initially set up pre-folded (once the arm64 contpte support is added in the next few patches). This leads to noticeable performance improvement during split. Acked-by: David Hildenbrand Signed-off-by: Ryan Roberts --- mm/huge_memory.c | 58 +++++++++++++++++++++++++++--------------------- 1 file changed, 33 insertions(+), 25 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 016e20bd813e..14888b15121e 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2579,15 +2579,16 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, pte = pte_offset_map(&_pmd, haddr); VM_BUG_ON(!pte); - for (i = 0, addr = haddr; i < HPAGE_PMD_NR; i++, addr += PAGE_SIZE) { - pte_t entry; - /* - * Note that NUMA hinting access restrictions are not - * transferred to avoid any possibility of altering - * permissions across VMAs. - */ - if (freeze || pmd_migration) { + + /* + * Note that NUMA hinting access restrictions are not transferred to + * avoid any possibility of altering permissions across VMAs. + */ + if (freeze || pmd_migration) { + for (i = 0, addr = haddr; i < HPAGE_PMD_NR; i++, addr += PAGE_SIZE) { + pte_t entry; swp_entry_t swp_entry; + if (write) swp_entry = make_writable_migration_entry( page_to_pfn(page + i)); @@ -2606,25 +2607,32 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, entry = pte_swp_mksoft_dirty(entry); if (uffd_wp) entry = pte_swp_mkuffd_wp(entry); - } else { - entry = mk_pte(page + i, READ_ONCE(vma->vm_page_prot)); - if (write) - entry = pte_mkwrite(entry, vma); - if (!young) - entry = pte_mkold(entry); - /* NOTE: this may set soft-dirty too on some archs */ - if (dirty) - entry = pte_mkdirty(entry); - if (soft_dirty) - entry = pte_mksoft_dirty(entry); - if (uffd_wp) - entry = pte_mkuffd_wp(entry); + + VM_WARN_ON(!pte_none(ptep_get(pte + i))); + set_pte_at(mm, addr, pte + i, entry); } - VM_BUG_ON(!pte_none(ptep_get(pte))); - set_pte_at(mm, addr, pte, entry); - pte++; + } else { + pte_t entry; + + entry = mk_pte(page, READ_ONCE(vma->vm_page_prot)); + if (write) + entry = pte_mkwrite(entry, vma); + if (!young) + entry = pte_mkold(entry); + /* NOTE: this may set soft-dirty too on some archs */ + if (dirty) + entry = pte_mkdirty(entry); + if (soft_dirty) + entry = pte_mksoft_dirty(entry); + if (uffd_wp) + entry = pte_mkuffd_wp(entry); + + for (i = 0; i < HPAGE_PMD_NR; i++) + VM_WARN_ON(!pte_none(ptep_get(pte + i))); + + set_ptes(mm, haddr, pte, entry, HPAGE_PMD_NR); } - pte_unmap(pte - 1); + pte_unmap(pte); if (!pmd_migration) folio_remove_rmap_pmd(folio, page, vma);