From patchwork Sat Sep 10 19:42:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Serge Semin X-Patchwork-Id: 12972647 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7228CC6FA82 for ; Sat, 10 Sep 2022 19:49:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=Xp/ChdvoMDZpRqbjAFB7FTGr3f67IDQTgx6fuu4Md6c=; b=WbnStzjGnlDd+X E8oQ5Yf7AC7RhYSnJl7JpEWlGZoDZ5StY6FZwQAelGV/UaQjwGFQbkO5+OatU3a95MCw9eLNmT8XG vYF3j1sATMAjpIKPBrxxUJkNk575XPjTLdKLf+C7d9+sxc7BW1Kf8s8SX5p49jh8OvDWE8e3zYF// 9x/UlnxQ1/nSKco1h1mGvBIE9QMTCVkqgUUZEjmZORfjwo+61ynLiX1S54BO2pXeShybvOK/ceI7M QoeFAgsLaWHdX+6DJ5kXLvnMTVWhmxmWoZIkHhr2cjN+VWL9ywx3bvrr1D/sHpHw9l5IYx9I6iQDb NJqTxtq+cIYu6UPeJBqg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oX6SN-00Chx1-4T; Sat, 10 Sep 2022 19:47:59 +0000 Received: from mail.baikalelectronics.com ([87.245.175.230]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oX6Nz-00Cewj-14 for linux-arm-kernel@lists.infradead.org; Sat, 10 Sep 2022 19:43:29 +0000 Received: from mail (mail.baikal.int [192.168.51.25]) by mail.baikalelectronics.com (Postfix) with ESMTP id 03A0ADC1; Sat, 10 Sep 2022 22:46:40 +0300 (MSK) DKIM-Filter: OpenDKIM Filter v2.11.0 mail.baikalelectronics.com 03A0ADC1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baikalelectronics.ru; s=mail; t=1662839200; bh=vEp5vkoF9dk/WJ15zsxLXpcxiQ/0IxoHzrqEveqf8CA=; h=From:To:CC:Subject:Date:In-Reply-To:References:From; b=PuwDCcNmDl/qm+7ZB2PpbcCRSflYJNwuM8XKAyXdXcoP5v8XLuzcia+fuEvpMCYFG Pb5CWICxqAaJf3ZVzZAC6PFHOlUOuhBTKyFKYPTteOYb+eXcqk6N1ua+OU3Pqy+QRd EE/CYIikTGCj27jFHHwzkLHYnhteWsVHa56iMnLo= Received: from localhost (192.168.168.10) by mail (192.168.51.25) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Sat, 10 Sep 2022 22:42:49 +0300 From: Serge Semin To: Rob Herring , Krzysztof Kozlowski , Michal Simek , Borislav Petkov , Mauro Carvalho Chehab , Tony Luck , James Morse , Robert Richter CC: Serge Semin , Serge Semin , Alexey Malahov , Michail Ivanov , Pavel Parkhomenko , Punnaiah Choudary Kalluri , Manish Narani , Dinh Nguyen , Rob Herring , Krzysztof Kozlowski , , , , Subject: [PATCH v2 13/19] EDAC/mc: Add MC unique index allocation procedure Date: Sat, 10 Sep 2022 22:42:31 +0300 Message-ID: <20220910194237.10142-14-Sergey.Semin@baikalelectronics.ru> In-Reply-To: <20220910194237.10142-1-Sergey.Semin@baikalelectronics.ru> References: <20220910194237.10142-1-Sergey.Semin@baikalelectronics.ru> MIME-Version: 1.0 X-ClientProxiedBy: MAIL.baikal.int (192.168.51.25) To mail (192.168.51.25) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220910_124327_486112_2E89ADCD X-CRM114-Status: GOOD ( 22.98 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org In case of the unique index allocation it's not that optimal to always rely on the low-level device drivers (platform drivers), because they get to start to implement either the same design pattern (for instance global static MC counter) or may end-up with having non-unique index eventually at runtime. Needless to say that having a generic unique index allocation/tracking procedure will make code more readable and safer. The suggested implementation is based on the kernel IDA infrastructure exposed by the lib/idr.c driver with API described in linux/idr.h header file. It's used to create an ID resource descriptor "mc_idr", which then is utilized either to track the custom MC idx specified by EDAC LLDDs or to allocate the next-free MC idx. A new special MC index is introduced here. It's defined by the EDAC_AUTO_MC_NUM macro with a value specifically chosen as the least probable value used for the real MC index. In case if the EDAC_AUTO_MC_NUM index is specified by the EDAC LLDD, the MC index will be either retrieved from the MC device OF-node alias index ("mc[:number:]") or automatically generated as the next-free MC index found by the ID allocation procedure. Signed-off-by: Serge Semin --- Note the approach implemented here has been partly ported from the SPI core driver using IDA to track/allocate SPI bus numbers. Link: https://elixir.bootlin.com/linux/latest/source/drivers/spi/spi.c#L2957 --- drivers/edac/edac_mc.c | 89 +++++++++++++++++++++++++++++++++++++++--- drivers/edac/edac_mc.h | 4 ++ 2 files changed, 87 insertions(+), 6 deletions(-) diff --git a/drivers/edac/edac_mc.c b/drivers/edac/edac_mc.c index 24814839d885..634c41ea7804 100644 --- a/drivers/edac/edac_mc.c +++ b/drivers/edac/edac_mc.c @@ -29,6 +29,9 @@ #include #include #include +#include +#include + #include #include "edac_mc.h" #include "edac_module.h" @@ -46,6 +49,7 @@ EXPORT_SYMBOL_GPL(edac_op_state); /* lock to memory controller's control array */ static DEFINE_MUTEX(mem_ctls_mutex); static LIST_HEAD(mc_devices); +static DEFINE_IDR(mc_idr); /* * Used to lock EDAC MC to just one module, avoiding two drivers e. g. @@ -493,7 +497,64 @@ void edac_mc_reset_delay_period(unsigned long value) mutex_unlock(&mem_ctls_mutex); } +/** + * edac_mc_alloc_id() - Allocate unique Memory Controller identifier + * + * @mci: pointer to the mci structure to allocate ID for + * + * Use edac_mc_free_id() to coherently free the MC identifier. + * + * .. note:: + * locking model: must be called with the mem_ctls_mutex lock held + * + * Returns: + * 0 on Success, or an error code on failure + */ +static int edac_mc_alloc_id(struct mem_ctl_info *mci) +{ + struct device_node *np = dev_of_node(mci->pdev); + int ret, min, max; + + if (mci->mc_idx == EDAC_AUTO_MC_NUM) { + ret = of_alias_get_id(np, "mc"); + if (ret >= 0) { + min = ret; + max = ret + 1; + } else { + min = of_alias_get_highest_id("mc"); + if (min >= 0) + min++; + else + min = 0; + + max = 0; + } + } else { + min = mci->mc_idx; + max = mci->mc_idx + 1; + } + + ret = idr_alloc(&mc_idr, mci, min, max, GFP_KERNEL); + if (ret < 0) + return ret == -ENOSPC ? -EBUSY : ret; + + mci->mc_idx = ret; + + return 0; +} +/** + * edac_mc_free_id() - Free Memory Controller identifier + * + * @mci: pointer to the mci structure to free ID from + * + * .. note:: + * locking model: must be called with the mem_ctls_mutex lock held + */ +static void edac_mc_free_id(struct mem_ctl_info *mci) +{ + idr_remove(&mc_idr, mci->mc_idx); +} /** * edac_mc_init_labels() - Initialize DIMM labels @@ -612,7 +673,8 @@ EXPORT_SYMBOL_GPL(edac_get_owner); int edac_mc_add_mc_with_groups(struct mem_ctl_info *mci, const struct attribute_group **groups) { - int ret = -EINVAL; + int ret; + edac_dbg(0, "\n"); #ifdef CONFIG_EDAC_DEBUG @@ -649,20 +711,30 @@ int edac_mc_add_mc_with_groups(struct mem_ctl_info *mci, goto fail0; } + ret = edac_mc_alloc_id(mci); + if (ret) { + edac_printk(KERN_ERR, EDAC_MC, "failed to allocate MC idx %u\n", + mci->mc_idx); + goto fail0; + } + edac_mc_init_labels(mci); - if (add_mc_to_global_list(mci)) - goto fail0; + if (add_mc_to_global_list(mci)) { + ret = -EINVAL; + goto fail1; + } /* set load time so that error rate can be tracked */ mci->start_time = jiffies; mci->bus = edac_get_sysfs_subsys(); - if (edac_create_sysfs_mci_device(mci, groups)) { + ret = edac_create_sysfs_mci_device(mci, groups); + if (ret) { edac_mc_printk(mci, KERN_WARNING, "failed to create sysfs device\n"); - goto fail1; + goto fail2; } if (mci->edac_check) { @@ -686,9 +758,12 @@ int edac_mc_add_mc_with_groups(struct mem_ctl_info *mci, mutex_unlock(&mem_ctls_mutex); return 0; -fail1: +fail2: del_mc_from_global_list(mci); +fail1: + edac_mc_free_id(mci); + fail0: mutex_unlock(&mem_ctls_mutex); return ret; @@ -716,6 +791,8 @@ struct mem_ctl_info *edac_mc_del_mc(struct device *dev) if (del_mc_from_global_list(mci)) edac_mc_owner = NULL; + edac_mc_free_id(mci); + mutex_unlock(&mem_ctls_mutex); if (mci->edac_check) diff --git a/drivers/edac/edac_mc.h b/drivers/edac/edac_mc.h index 881b00eadf7a..4b6676235b1b 100644 --- a/drivers/edac/edac_mc.h +++ b/drivers/edac/edac_mc.h @@ -23,6 +23,7 @@ #define _EDAC_MC_H_ #include +#include #include #include #include @@ -37,6 +38,9 @@ #include #include +/* Generate MC identifier automatically */ +#define EDAC_AUTO_MC_NUM UINT_MAX + #if PAGE_SHIFT < 20 #define PAGES_TO_MiB(pages) ((pages) >> (20 - PAGE_SHIFT)) #define MiB_TO_PAGES(mb) ((mb) << (20 - PAGE_SHIFT))