From patchwork Mon Feb 17 14:48:28 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Li Ming X-Patchwork-Id: 13978032 Received: from sender4-pp-o94.zoho.com (sender4-pp-o94.zoho.com [136.143.188.94]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1E1C42248AC; Mon, 17 Feb 2025 14:52:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.94 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739803949; cv=pass; b=jjpMF52PiuwBPtvR0qr4kyo3NcwrVioWx/F1TV0NuF6CAvEnq9a46BOjofix7pvtiwrluVj9Zeew5oZMOQA2kcDbYHrrdeZW/teBN0xl0beYHdERbzd7BmB2JaBSrf5gDO1W0znbYiPHotOMWuJ/bZfFygGWrn17yCkIoboRT0s= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739803949; c=relaxed/simple; bh=JRmCF9LjmJYKWivhjQ6n8IMZFxSXDeNdiP8wgPC7wg0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=EkkZGQ5h2PeTNLYz7333gduhTT6310n1Xw+Yf2bS4icVps5TRLkmzLVBaNgsTMop9vkrL06p/f5NO5Hds9AsKS5rSYz3Ja6PbUDC/MM6Tn5TFSiD6nzecyGU5ZHxB5UZDSZG8YHaZjEYQrve5MZrYeVi5LVkBr6NE0DEAYL/QJ8= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=zohomail.com; spf=pass smtp.mailfrom=zohomail.com; dkim=pass (1024-bit key) header.d=zohomail.com header.i=ming.li@zohomail.com header.b=TW/TVcc6; arc=pass smtp.client-ip=136.143.188.94 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=zohomail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=zohomail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=zohomail.com header.i=ming.li@zohomail.com header.b="TW/TVcc6" ARC-Seal: i=1; a=rsa-sha256; t=1739803806; cv=none; d=zohomail.com; s=zohoarc; b=UqiwUddfNdEJ/ycmxXdmA38GekVPzC7NL83fV3PdbunGGkpW6BZWqBg/mz4jExLuehulmOar8psrWw0AZbsH72dDH27ioAcXgTbXsgeHcZ6/rrK+tTd2mNjcbO2xbVWmAqf5A0pFyBRk7+poykB50JNs3/2ifC24z6Dl7xirPkI= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1739803806; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:Subject:To:To:Message-Id:Reply-To; bh=u5TjcDD2fVC5Z7fmg3HTZT6iZIZPELI9FVatCCA70pE=; b=JCObFY58kyM/3qfU+hAY6rnwKW7vc+YW4EJSIFVrDEIYBrnt1IWnU5SsVQk2qb+aJ+nwSCz7UDsB0QUl6NQYQ3W8xl64UBR2HE9MMg2j71WMMuIfSZHFBwdsqAgaegonNS2m3xWjK/aDb2xJDxFxPEXZEePKmSuZGSPUv3x6idU= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=zohomail.com; spf=pass smtp.mailfrom=ming.li@zohomail.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1739803806; s=zm2022; d=zohomail.com; i=ming.li@zohomail.com; h=From:From:To:To:Cc:Cc:Subject:Subject:Date:Date:Message-Id:Message-Id:In-Reply-To:References:MIME-Version:Content-Transfer-Encoding:Feedback-ID:Reply-To; bh=u5TjcDD2fVC5Z7fmg3HTZT6iZIZPELI9FVatCCA70pE=; b=TW/TVcc6KoDGSDzqzNLWxrpINcDFMI7E9zZAO83NE9Ib/LB7/BNAkA69CRhKCD6d 93doKC2o251DrvXKPZqiYwJTWJLFEbjIBzH3lgtaC8xKsCR51yPPrjuhxxDK4KycWja mphbbfrvlBGGnOzb889zmvUy7BLnwTRS+jLz5sac= Received: by mx.zohomail.com with SMTPS id 173980380247995.30722494540043; Mon, 17 Feb 2025 06:50:02 -0800 (PST) From: Li Ming To: dave@stgolabs.net, jonathan.cameron@huawei.com, dave.jiang@intel.com, alison.schofield@intel.com, vishal.l.verma@intel.com, ira.weiny@intel.com, dan.j.williams@intel.com Cc: linux-cxl@vger.kernel.org, linux-kernel@vger.kernel.org, Li Ming Subject: [PATCH v2 7/7] cxl/region: Drop goto pattern of construct_region() Date: Mon, 17 Feb 2025 22:48:28 +0800 Message-Id: <20250217144828.30651-8-ming.li@zohomail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250217144828.30651-1-ming.li@zohomail.com> References: <20250217144828.30651-1-ming.li@zohomail.com> Precedence: bulk X-Mailing-List: linux-cxl@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Feedback-ID: rr080112270a1b3a40a4862390f0c7011f0000a6533c9e532b319b72bcea67a4ff7b47a766f9ac6b7a87cf67:zu08011227637483a4a31eb2f0b8ceb2e6000059b8d4e13f7089160e231c8be7dbb43f030a73e70a3b9635e1:rf0801122d5c87afa6af03d5275597f33e000026a3925e33887a0b88a34465cb4731f8771e61e7a209610abb740fad050b8a:ZohoMail X-ZohoMailClient: External Some operations need to be protected by the cxl_region_rwsem in construct_region(). Currently, construct_region() uses down_write() and up_write() for the cxl_region_rwsem locking, so there is a goto pattern after down_write() invoked to release cxl_region_rwsem. construct region() can be optimized to remove the goto pattern. The changes are creating a new function called construct_auto_region() which will include all checking and operations protected by the cxl_region_rwsem, and using guard(rwsem_write) to replace down_write() and up_write() in construct_auto_region(). Signed-off-by: Li Ming Reviewed-by: Jonathan Cameron Reviewed-by: Dave Jiang Reviewed-by: Alison Schofield Reviewed-by: Dan Williams --- v2: - Rename __construct_region() to construct_auto_region(). (Jonathan and Dave) --- drivers/cxl/core/region.c | 71 +++++++++++++++++++++------------------ 1 file changed, 39 insertions(+), 32 deletions(-) diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c index 320a3f218131..7a9e51aba9f4 100644 --- a/drivers/cxl/core/region.c +++ b/drivers/cxl/core/region.c @@ -3216,49 +3216,31 @@ static int match_region_by_range(struct device *dev, const void *data) return 0; } -/* Establish an empty region covering the given HPA range */ -static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd, - struct cxl_endpoint_decoder *cxled) +static int construct_auto_region(struct cxl_region *cxlr, + struct cxl_root_decoder *cxlrd, + struct cxl_endpoint_decoder *cxled) { struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); - struct cxl_port *port = cxlrd_to_port(cxlrd); struct range *hpa = &cxled->cxld.hpa_range; struct cxl_region_params *p; - struct cxl_region *cxlr; struct resource *res; int rc; - do { - cxlr = __create_region(cxlrd, cxled->mode, - atomic_read(&cxlrd->region_id)); - } while (IS_ERR(cxlr) && PTR_ERR(cxlr) == -EBUSY); - - if (IS_ERR(cxlr)) { - dev_err(cxlmd->dev.parent, - "%s:%s: %s failed assign region: %ld\n", - dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), - __func__, PTR_ERR(cxlr)); - return cxlr; - } - - down_write(&cxl_region_rwsem); + guard(rwsem_write)(&cxl_region_rwsem); p = &cxlr->params; if (p->state >= CXL_CONFIG_INTERLEAVE_ACTIVE) { dev_err(cxlmd->dev.parent, "%s:%s: %s autodiscovery interrupted\n", dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), __func__); - rc = -EBUSY; - goto err; + return -EBUSY; } set_bit(CXL_REGION_F_AUTO, &cxlr->flags); res = kmalloc(sizeof(*res), GFP_KERNEL); - if (!res) { - rc = -ENOMEM; - goto err; - } + if (!res) + return -ENOMEM; *res = DEFINE_RES_MEM_NAMED(hpa->start, range_len(hpa), dev_name(&cxlr->dev)); @@ -3281,7 +3263,7 @@ static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd, rc = sysfs_update_group(&cxlr->dev.kobj, get_cxl_region_target_group()); if (rc) - goto err; + return rc; dev_dbg(cxlmd->dev.parent, "%s:%s: %s %s res: %pr iw: %d ig: %d\n", dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), __func__, @@ -3290,14 +3272,39 @@ static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd, /* ...to match put_device() in cxl_add_to_region() */ get_device(&cxlr->dev); - up_write(&cxl_region_rwsem); - return cxlr; + return 0; +} -err: - up_write(&cxl_region_rwsem); - devm_release_action(port->uport_dev, unregister_region, cxlr); - return ERR_PTR(rc); +/* Establish an empty region covering the given HPA range */ +static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd, + struct cxl_endpoint_decoder *cxled) +{ + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + struct cxl_port *port = cxlrd_to_port(cxlrd); + struct cxl_region *cxlr; + int rc; + + do { + cxlr = __create_region(cxlrd, cxled->mode, + atomic_read(&cxlrd->region_id)); + } while (IS_ERR(cxlr) && PTR_ERR(cxlr) == -EBUSY); + + if (IS_ERR(cxlr)) { + dev_err(cxlmd->dev.parent, + "%s:%s: %s failed assign region: %ld\n", + dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), + __func__, PTR_ERR(cxlr)); + return cxlr; + } + + rc = construct_auto_region(cxlr, cxlrd, cxled); + if (rc) { + devm_release_action(port->uport_dev, unregister_region, cxlr); + return ERR_PTR(rc); + } + + return cxlr; } int cxl_add_to_region(struct cxl_port *root, struct cxl_endpoint_decoder *cxled)