From patchwork Wed Apr 13 06:01:44 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Williams X-Patchwork-Id: 12811530 Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) (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 02F2D23D4 for ; Wed, 13 Apr 2022 06:02:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1649829741; x=1681365741; h=subject:from:to:cc:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=WeXGisg3F5xd5CDMy9xUZA6jIDX7Clw9WAukSk7hrxY=; b=kTCeSE/5XAvigLUqn+HFbYs89/RWl/ultYr/2T/8Ll+LzFsUw51Tqgjx ctl9GmrQP5Sfn4B2jeBECFUbq1g8Y0Vx1p8C9bNK+928NjKYWuJHg7B78 GExqhhFDPT46uU1z7fq3Ri6CGR5jzFQzUwM++L4CqIsJOn5TiWR59zRoc 17Vgh4PgxF32Cn1sSonNj9bmY1EV3DyDaQmqgE5n90GUKpMEaRtYObXZI Vx13dTD+uGFGQxo23goHEQBYTvtPlod8cGRyJs0OhhqoDXpZ5EaSIC4ZB DXrVp4RZGbrgpb+HF0IPuOQMYgrqD7vk1fjuHehE3U+zpPulXiEATgj6C A==; X-IronPort-AV: E=McAfee;i="6400,9594,10315"; a="262335017" X-IronPort-AV: E=Sophos;i="5.90,256,1643702400"; d="scan'208";a="262335017" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Apr 2022 23:02:05 -0700 X-IronPort-AV: E=Sophos;i="5.90,256,1643702400"; d="scan'208";a="623559249" Received: from dwillia2-desk3.jf.intel.com (HELO dwillia2-desk3.amr.corp.intel.com) ([10.54.39.25]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Apr 2022 23:01:44 -0700 Subject: [PATCH v2 03/12] cxl/core: Refactor a cxl_lock_class() out of cxl_nested_lock() From: Dan Williams To: linux-cxl@vger.kernel.org Cc: Alison Schofield , Vishal Verma , Ira Weiny , Ben Widawsky , Jonathan Cameron , Dave Jiang , Kevin Tian , peterz@infradead.org, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, nvdimm@lists.linux.dev Date: Tue, 12 Apr 2022 23:01:44 -0700 Message-ID: <164982970436.684294.12004091884213856239.stgit@dwillia2-desk3.amr.corp.intel.com> In-Reply-To: <164982968798.684294.15817853329823976469.stgit@dwillia2-desk3.amr.corp.intel.com> References: <164982968798.684294.15817853329823976469.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.18-3-g996c Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In preparation for upleveling device_lock() lockdep annotation support into the core, provide a helper to retrieve the lock class. This lock_class will be used with device_set_lock_class() to identify the CXL nested locking rules. Cc: Alison Schofield Cc: Vishal Verma Cc: Ira Weiny Cc: Ben Widawsky Reviewed-by: Jonathan Cameron Reviewed-by: Dave Jiang Reviewed-by: Kevin Tian Signed-off-by: Dan Williams --- drivers/cxl/cxl.h | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index 990b6670222e..c9fda9304c54 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -418,13 +418,12 @@ enum cxl_lock_class { */ }; -static inline void cxl_nested_lock(struct device *dev) +static inline int cxl_lock_class(struct device *dev) { if (is_cxl_port(dev)) { struct cxl_port *port = to_cxl_port(dev); - mutex_lock_nested(&dev->lockdep_mutex, - CXL_PORT_LOCK + port->depth); + return CXL_PORT_LOCK + port->depth; } else if (is_cxl_decoder(dev)) { struct cxl_port *port = to_cxl_port(dev->parent); @@ -432,14 +431,18 @@ static inline void cxl_nested_lock(struct device *dev) * A decoder is the immediate child of a port, so set * its lock class equal to other child device siblings. */ - mutex_lock_nested(&dev->lockdep_mutex, - CXL_PORT_LOCK + port->depth + 1); + return CXL_PORT_LOCK + port->depth + 1; } else if (is_cxl_nvdimm_bridge(dev)) - mutex_lock_nested(&dev->lockdep_mutex, CXL_NVDIMM_BRIDGE_LOCK); + return CXL_NVDIMM_BRIDGE_LOCK; else if (is_cxl_nvdimm(dev)) - mutex_lock_nested(&dev->lockdep_mutex, CXL_NVDIMM_LOCK); + return CXL_NVDIMM_LOCK; else - mutex_lock_nested(&dev->lockdep_mutex, CXL_ANON_LOCK); + return CXL_ANON_LOCK; +} + +static inline void cxl_nested_lock(struct device *dev) +{ + mutex_lock_nested(&dev->lockdep_mutex, cxl_lock_class(dev)); } static inline void cxl_nested_unlock(struct device *dev)