From patchwork Wed Jun 14 19:20:42 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stephan Gerhold X-Patchwork-Id: 692642 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9EBD9C0015E for ; Wed, 14 Jun 2023 19:20:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235998AbjFNTU5 (ORCPT ); Wed, 14 Jun 2023 15:20:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47200 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235377AbjFNTU4 (ORCPT ); Wed, 14 Jun 2023 15:20:56 -0400 Received: from mo4-p02-ob.smtp.rzone.de (mo4-p02-ob.smtp.rzone.de [85.215.255.82]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 81B3B213F; Wed, 14 Jun 2023 12:20:53 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1686770450; cv=none; d=strato.com; s=strato-dkim-0002; b=e+FzeiGmNyPUcMNfIoFrMokIUBpwxFNnsbXhzQtr7tU7CfBtBDWs/shxjnNi5sAB4G j3Xzr0NNGiR86ueeKzgw8jd2mqUpS+vZsUNMqb243whVTYm9QLfULVw7eyDsSHM5QWly OlO3kCLWxONMcbgWpU0jp1ILS/x/46Kcdwzn0nL+LZzX1JvU9fHEbYhcFAOEOAQ4nfUB UBh0kFjYVv2+rp4sF9JFzjNp1iCd+73blPG1bOZXTFPWGGxl3bJvyqW1R41n5F0AncIt okmKsl1B8gUSXZII4bY4P/BfyE4tzpMQCNwV5SYEMfV0kHF1LZQgX95ZPs8xlno2/FWT PR1g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; t=1686770450; s=strato-dkim-0002; d=strato.com; h=Cc:To:In-Reply-To:References:Message-Id:Subject:Date:From:Cc:Date: From:Subject:Sender; bh=LdeZ5ShzM18y4oy4q0pM7ga3Ybusf7cQdOu55GJ4/fM=; b=tMgPvQdPiE4sjQrE43YGJcftGU4EGRFN9SuxfDpGmEkoFTTFoxHsSWPuEnAxwEaHDt b3euHjIaN+AW9XbBAAicwEthYqj9CXgZupocZOFWLvN0XG2rUsi278mvvXJKWBmZM/ZO X0DLCDTWLTZcWvSViK7vpY/wdTNN0z0xJh5gNuauJjW+6EG4Kf/e2p/vmEkhzzCXJWc3 NLuo4yJPnG1z2qz6heLk8oMR+JFcuZaD/mmhy2+iWPKtHxb5wTxI4mVfWJOKpfkZHiZF n3hbAP/QvErdveLHp3DADDGnaHCMyEtVIy0wfCivMrafXdW9PupSDjzFRsCuU/Xt4xwe lV+w== ARC-Authentication-Results: i=1; strato.com; arc=none; dkim=none X-RZG-CLASS-ID: mo02 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1686770450; s=strato-dkim-0002; d=gerhold.net; h=Cc:To:In-Reply-To:References:Message-Id:Subject:Date:From:Cc:Date: From:Subject:Sender; bh=LdeZ5ShzM18y4oy4q0pM7ga3Ybusf7cQdOu55GJ4/fM=; b=RDIc6K+fuXpn+9U5xbQluGWN1tgqNZJYFYq4GDD0iS3/xDUUFGzInbbvzPajYjB73X l2DFMTkStTsx+PL8CM6AtcKiaxcWDRBYfp8JuHyxoS3b8qAyI3FU7xF20N3LgN+g0fHD 3QjAkWZo0Osgpw8PVDsXPd/bTu1yCT7TGBIUzdTdwDPDmXD40tOKyxS1aggktUombb8v 64uOcLHy/PeP4J01/bPiumT0NACjWecbgBMoT+kow05FaR51v0jJY10Aq8W1H572TWi+ nF1pe6nC75hQkW7GgsKvGdsvEK1j3/49DTvE/Tww1abEjKyDXKhxSFJkdJJoWbUD9kC9 nqpQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; t=1686770450; s=strato-dkim-0003; d=gerhold.net; h=Cc:To:In-Reply-To:References:Message-Id:Subject:Date:From:Cc:Date: From:Subject:Sender; bh=LdeZ5ShzM18y4oy4q0pM7ga3Ybusf7cQdOu55GJ4/fM=; b=59cCZ4+6c3YKIGO5o78XtZ1x4mwKdt3EUHOR88YMGTRprtTBgUWfX3GIK4tenqjbTP aa/Rbkx//GSW5G0FNSAA== X-RZG-AUTH: ":P3gBZUipdd93FF5ZZvYFPugejmSTVR2nRPhVOQjVd4CteZ/7jYgS+mLFY+H0JAn8u4xxmw==" Received: from [192.168.244.3] by smtp.strato.de (RZmta 49.6.0 DYNA|AUTH) with ESMTPSA id D0d0a8z5EJKo0hs (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256 bits)) (Client did not present a certificate); Wed, 14 Jun 2023 21:20:50 +0200 (CEST) From: Stephan Gerhold Date: Wed, 14 Jun 2023 21:20:42 +0200 Subject: [PATCH v2 1/2] of: reserved_mem: Try to keep range allocations contiguous MIME-Version: 1.0 Message-Id: <20230510-dt-resv-bottom-up-v2-1-aeb2afc8ac25@gerhold.net> References: <20230510-dt-resv-bottom-up-v2-0-aeb2afc8ac25@gerhold.net> In-Reply-To: <20230510-dt-resv-bottom-up-v2-0-aeb2afc8ac25@gerhold.net> To: Rob Herring , Krzysztof Kozlowski , Conor Dooley , Frank Rowand Cc: Andy Gross , Bjorn Andersson , Konrad Dybcio , devicetree@vger.kernel.org, devicetree-spec@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, Stephan Gerhold X-Mailer: b4 0.12.2 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Right now dynamic reserved memory regions are allocated either bottom-up or top-down, depending on the memblock setting of the architecture. This is fine when the address is arbitrary. However, when using "alloc-ranges" the regions are often placed somewhere in the middle of (free) RAM, even if the range starts or ends next to another (static) reservation. Try to detect this situation, and choose explicitly between bottom-up or top-down to allocate the memory close to the other reservations: 1. If the "alloc-range" starts at the end or inside an existing reservation, use bottom-up. 2. If the "alloc-range" ends at the start or inside an existing reservation, use top-down. 3. If both or none is the case, keep the current (architecture-specific) behavior. There are plenty of edge cases where only a more complex algorithm would help, but even this simple approach helps in many cases to keep the reserved memory (and therefore also the free memory) contiguous. Signed-off-by: Stephan Gerhold --- drivers/of/of_reserved_mem.c | 55 ++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 53 insertions(+), 2 deletions(-) diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c index 948efa9f99e3..7f892c3dcc63 100644 --- a/drivers/of/of_reserved_mem.c +++ b/drivers/of/of_reserved_mem.c @@ -77,6 +77,57 @@ void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname, return; } +/* + * __reserved_mem_alloc_in_range() - allocate reserved memory described with + * 'alloc-ranges'. Choose bottom-up/top-down depending on nearby existing + * reserved regions to keep the reserved memory contiguous if possible. + */ +static int __init __reserved_mem_alloc_in_range(phys_addr_t size, + phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap, + phys_addr_t *res_base) +{ + bool prev_bottom_up = memblock_bottom_up(); + bool bottom_up = false, top_down = false; + int ret, i; + + for (i = 0; i < reserved_mem_count; i++) { + struct reserved_mem *rmem = &reserved_mem[i]; + + /* Skip regions that were not reserved yet */ + if (rmem->size == 0) + continue; + + /* + * If range starts next to an existing reservation, use bottom-up: + * |....RRRR................RRRRRRRR..............| + * --RRRR------ + */ + if (start >= rmem->base && start <= (rmem->base + rmem->size)) + bottom_up = true; + + /* + * If range ends next to an existing reservation, use top-down: + * |....RRRR................RRRRRRRR..............| + * -------RRRR----- + */ + if (end >= rmem->base && end <= (rmem->base + rmem->size)) + top_down = true; + } + + /* Change setting only if either bottom-up or top-down was selected */ + if (bottom_up != top_down) + memblock_set_bottom_up(bottom_up); + + ret = early_init_dt_alloc_reserved_memory_arch(size, align, + start, end, nomap, res_base); + + /* Restore old setting if needed */ + if (bottom_up != top_down) + memblock_set_bottom_up(prev_bottom_up); + + return ret; +} + /* * __reserved_mem_alloc_size() - allocate reserved memory described by * 'size', 'alignment' and 'alloc-ranges' properties. @@ -137,8 +188,8 @@ static int __init __reserved_mem_alloc_size(unsigned long node, end = start + dt_mem_next_cell(dt_root_size_cells, &prop); - ret = early_init_dt_alloc_reserved_memory_arch(size, - align, start, end, nomap, &base); + ret = __reserved_mem_alloc_in_range(size, align, + start, end, nomap, &base); if (ret == 0) { pr_debug("allocated memory for '%s' node: base %pa, size %lu MiB\n", uname, &base,