From patchwork Thu Sep 29 23:27:08 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Serge Semin X-Patchwork-Id: 12996231 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 5C13BC43219 for ; Sat, 1 Oct 2022 01:14:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232457AbiJABOb (ORCPT ); Fri, 30 Sep 2022 21:14:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37658 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232644AbiJABO0 (ORCPT ); Fri, 30 Sep 2022 21:14:26 -0400 Received: from post.baikalelectronics.com (post.baikalelectronics.com [213.79.110.86]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id CABCD6409; Fri, 30 Sep 2022 18:14:20 -0700 (PDT) Received: from post.baikalelectronics.com (localhost.localdomain [127.0.0.1]) by post.baikalelectronics.com (Proxmox) with ESMTP id 1E4BAE0ECB; Fri, 30 Sep 2022 02:27:33 +0300 (MSK) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= baikalelectronics.ru; h=cc:cc:content-transfer-encoding :content-type:content-type:date:from:from:in-reply-to:message-id :mime-version:references:reply-to:subject:subject:to:to; s=post; bh=Wuk4O59cXcttSrtKFRFPt0XppdcnPe6R4xFVev7zIkQ=; b=dim4L7bcOXJT IXolNndmVAqP3ESV7nSU2apun8ZRF/HFNoMYt29HdhF5pidhizd8AvipTU8RzkSo 8vIKUVAyrftByPGcOFnZaSzjmvZOkpaYd2NuggMZRW7l5yyRLL8RJws/r/nDFUjW tsGTHGAFCOybFIUCGAigG8TxT/jL1ZA= Received: from mail.baikal.int (mail.baikal.int [192.168.51.25]) by post.baikalelectronics.com (Proxmox) with ESMTP id 0F7A5E0E6B; Fri, 30 Sep 2022 02:27:33 +0300 (MSK) Received: from localhost (192.168.168.10) by mail (192.168.51.25) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Fri, 30 Sep 2022 02:27:33 +0300 From: Serge Semin To: 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 , Rob Herring , Krzysztof Kozlowski , , , , Subject: [PATCH RESEND v3 13/17] EDAC/mc: Add MC unique index allocation procedure Date: Fri, 30 Sep 2022 02:27:08 +0300 Message-ID: <20220929232712.12202-14-Sergey.Semin@baikalelectronics.ru> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20220929232712.12202-1-Sergey.Semin@baikalelectronics.ru> References: <20220929232712.12202-1-Sergey.Semin@baikalelectronics.ru> MIME-Version: 1.0 X-Originating-IP: [192.168.168.10] X-ClientProxiedBy: MAIL.baikal.int (192.168.51.25) To mail (192.168.51.25) Precedence: bulk List-ID: X-Mailing-List: linux-edac@vger.kernel.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))