From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 8167E1A5B84; Wed, 30 Apr 2025 14:59:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746025179; cv=none; b=nntuW32uX2GAiTKkW+5soOeUcYJ8GChQotIK436HMdOnzXpryeKUy6hmUbLjiE9Nh6L3c2W67NFqBEi3kQGrBDcla3XCTAVTspRPdeeJg7H1U9p2Prh2++OiBUGcLvtkLvlrVrIFxvUFkMN5cyfTjX23jX3XbWQCr+onhuz92Js= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746025179; c=relaxed/simple; bh=RhAzlCJbPtUUpaoj2kdnNovqzYuOnqKFmxO+EPw/OLA=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=nhELvvDwrbHDsgkOsjaNkA942A3KG0jf8oT1/b/kbfuW6HDMbfQTiWWj7a/SVmna22ZU1fKA8IlO5U1y0SYOb97U1Zk8xmHJ4z28lO4EV0lmpycQPFM0gqW6oSgCzEExq1bCZxNIZREIThmfm5t44z15ZFxdnJ3cGPS9ms0Ewl8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com 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 66C201007; Wed, 30 Apr 2025 07:59:24 -0700 (PDT) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.27]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B37EC3F5A1; Wed, 30 Apr 2025 07:59:29 -0700 (PDT) From: Ryan Roberts To: Andrew Morton , "Matthew Wilcox (Oracle)" , Alexander Viro , Christian Brauner , Jan Kara , David Hildenbrand , Dave Chinner , Catalin Marinas , Will Deacon , Kalesh Singh , Zi Yan Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: [RFC PATCH v4 0/5] Readahead tweaks for larger folios Date: Wed, 30 Apr 2025 15:59:13 +0100 Message-ID: <20250430145920.3748738-1-ryan.roberts@arm.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi All, This RFC series adds some tweaks to readahead so that it does a better job of ramping up folio sizes as readahead extends further into the file. And it additionally special-cases executable mappings to allow the arch to request a preferred folio size for text. Previous versions of the series focussed on the latter part only (large folios for text). See [3]. But after discussion with Matthew Wilcox last week, we decided that we should really be fixing some of the unintended behaviours in how a folio size is selected in general before special-casing for text. As a result patches 1-4 make folio size selection behave more sanely, then patch 5 introduces large folios for text. Patch 5 depends on patch 1, but does not depend on patches 2-4. --- I'm leaving this marked as RFC for now as I intend to do more testing, and haven't yet updated the benchmark results in patch 5 (although I expect them to be similar). Applies on top of Monday's mm-unstable (b18dec6a6ad3) and passes all mm kselftests. Changes since v3 [3] ==================== - Added patchs 1-4 to do better job of ramping up folio order - In patch 5: - Confine readahead blocks to vma boundaries (per Kalesh) - Rename arch_exec_folio_order() to exec_folio_order() (per Matthew) - exec_folio_order() now returns unsigned int and defaults to order-0 (per Matthew) - readahead size is honoured (including when disabled) Changes since v2 [2] ==================== - Rename arch_wants_exec_folio_order() to arch_exec_folio_order() (per Andrew) - Fixed some typos (per Andrew) Changes since v1 [1] ==================== - Remove "void" from arch_wants_exec_folio_order() macro args list [1] https://lore.kernel.org/linux-mm/20240111154106.3692206-1-ryan.roberts@arm.com/ [2] https://lore.kernel.org/all/20240215154059.2863126-1-ryan.roberts@arm.com/ [3] https://lore.kernel.org/linux-mm/20250327160700.1147155-1-ryan.roberts@arm.com/ Thanks, Ryan Ryan Roberts (5): mm/readahead: Honour new_order in page_cache_ra_order() mm/readahead: Terminate async readahead on natural boundary mm/readahead: Make space in struct file_ra_state mm/readahead: Store folio order in struct file_ra_state mm/filemap: Allow arch to request folio size for exec memory arch/arm64/include/asm/pgtable.h | 8 +++++ include/linux/fs.h | 4 ++- include/linux/pgtable.h | 11 +++++++ mm/filemap.c | 55 ++++++++++++++++++++++++-------- mm/internal.h | 3 +- mm/readahead.c | 27 +++++++++------- 6 files changed, 81 insertions(+), 27 deletions(-) -- 2.43.0