From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.remote-ip=198.175.65.16 ARC-Seal: i=2; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=fail; t=1792439644; b=XMSDr+ourXOHtI+W4AP7H79i+RP/PmIRiIhcIBK9p6NaAQGi2P4d7ID+9zK/yyxCT7bg kMlUYSFTCOBbecGr1fVRETgHxHx4SK1lOLaH8ZBz8thbx2jQkTV5fkfmfOPAqEBO0x9tj Q1WXO9XQI9ENywkZW/VDrmwAgeh1tRjyVezQ4oGMm+g8ylKGrIJyp7h4fOt76/C1prSBN Lzs82qO9kgoijo+iVCxqnVRoIEeDRoeHHBql0eyMr44x3vNTD2n6axyMwsoO6tkJ/F8lT d7UrUAALqgBqH1mHW4ySEJj9hA63bDlhSTKlrbPiFzzaiW0YrlDbQgZNsmOmtzAom/w== ARC-Message-Signature: i=2; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792439644; h=DMARC-Filter:DKIM-Signature:X-CSE-ConnectionGUID:X-CSE-MsgGUID: X-IronPort-AV:X-IronPort-AV:Received:X-CSE-ConnectionGUID: X-CSE-MsgGUID:X-ExtLoop1:X-IronPort-AV:Received:Received:Received: Received:Received:Received:Date:From:To:CC:Subject:Message-ID: References:Content-Type:Content-Disposition:In-Reply-To: X-ClientProxiedBy:MIME-Version:X-MS-PublicTrafficType: X-MS-TrafficTypeDiagnostic:X-MS-Office365-Filtering-Correlation-Id: X-MS-Exchange-SenderADCheck:X-MS-Exchange-AntiSpam-Relay: X-Microsoft-Antispam:X-Microsoft-Antispam-Message-Info: X-Forefront-Antispam-Report: X-MS-Exchange-AntiSpam-MessageData-ChunkCount: X-MS-Exchange-AntiSpam-MessageData-0:X-Exchange-RoutingPolicyChecked: X-MS-Exchange-CrossTenant-Network-Message-Id: X-MS-Exchange-CrossTenant-AuthSource:X-MS-Exchange-CrossTenant-AuthAs: X-MS-Exchange-CrossTenant-OriginalArrivalTime: X-MS-Exchange-CrossTenant-FromEntityHeader: X-MS-Exchange-CrossTenant-Id:X-MS-Exchange-CrossTenant-MailboxType: X-MS-Exchange-CrossTenant-UserPrincipalName: X-MS-Exchange-Transport-CrossTenantHeadersStamped:X-OriginatorOrg; bh=1m6VwGvU2i9VkH2lxzW589AnGPUyCBiVKofI75V/BjI=; b=IqvCKjggPWv35Fcsvwddsh8L8CwOjth4uTls2uWaCjoTrW2JprABN3yEYUOzSjk5Z2xW vzh3X9AuSGpGQO3WS/+HOYtdfe7h7rTKryYc22+jzvoDE8VTOoY61T9GGrWg52fvm/9Db hi8MGXK1FXPDF0D/R46zPy3ysJfQFxGUfDDg8pKZUX9zWnQil8s6BxmyeZ4ifDoA1XXCX GpHu21jIgL8fKBqc+X5KAv6KLzp9dpyVPw4qNx0xB0yTys7QaEm95DTti7xE+5ye8Z9fM FkZ+q46KC1wi45oOtLqarAY6XM59uls2cwjxkXjIR7zRyRWRvuiEe3+e+o8G/Ozeiig== ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=V9ARP30J; arc=fail smtp.remote-ip=198.175.65.16 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.16]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1EED0606A31B for ; Mon, 19 Oct 2026 19:54:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 1EED0606A31B Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=V9ARP30J DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1792439643; x=1823975643; h=date:from:to:cc:subject:message-id:references: in-reply-to:mime-version; bh=JZ8PtHWXsLDwBDPsO5XEVgkcKx1w9wjtN4E/HXR2JHU=; b=V9ARP30JnfAX12sgiTxFY2dFT6HbbPSNQ3zYqjJXGxTgFLVspzYBYUPy 2Bay2NiySnOHRuyPxUPgugmxhld+vbS5/0BB9LulxJoGcSjOEUr+f88a5 3t4vDggNKXnBzQ7xNT3Bm3yGtY2Ft1wC/KOCa2eyiyywwG34lILHUlQiS 1cm/r6cteiqrKryPfPAJ3eBzx9X8dKZQNJOEu8TsVyu1Hqmqs3IZ4bith bGz5sOUc5cmWJUg3/tY74pxIavx0mGb9wLpb+DSLQmevU7qzWVLSFseES KDFYxvCbPpxuUIdzD+0cI9KXdOJfsv/bxvr1JA8MHluB2WTatntj008At g==; X-CSE-ConnectionGUID: vh+MW7RNRIKUC3l0D180OQ== X-CSE-MsgGUID: skDCd5M/RVO2BYardR2YGA== X-IronPort-AV: E=McAfee;i="6800,10657,11940"; a="1127418" X-IronPort-AV: E=Sophos;i="6.27,167,1787036400"; d="scan'208";a="1127418" Received: from orviesa003.jf.intel.com ([10.64.159.143]) by orvoesa108.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Oct 2026 12:54:03 -0700 X-CSE-ConnectionGUID: +08MC7+bTqKNBmDv5vzu7A== X-CSE-MsgGUID: 27rwBgkaRb6+Y5LJTf65iA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,167,1787036400"; d="scan'208";a="2594713" Received: from fmsmsx903.amr.corp.intel.com ([10.18.126.92]) by orviesa003.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Oct 2026 12:54:02 -0700 Received: from FMSMSX903.amr.corp.intel.com (10.18.126.92) by fmsmsx903.amr.corp.intel.com (10.18.126.92) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.49; Mon, 19 Oct 2026 12:54:02 -0700 Received: from fmsedg903.ED.cps.intel.com (10.1.192.145) by FMSMSX903.amr.corp.intel.com (10.18.126.92) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.49 via Frontend Transport; Mon, 19 Oct 2026 12:54:02 -0700 Received: from PH0PR06CU001.outbound.protection.outlook.com (40.107.208.69) by edgegateway.intel.com (192.55.55.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.49; Mon, 19 Oct 2026 12:54:02 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=kigtUqRJ/kYvUc1BxwJMjXUbkgk4FEpsQqjd21Iay6+olYdMgIU3A3kltxhSIcZEy9l7h6R/9SIvIxsyPNHTG3Z7pSmbZFzAEeXxTGRQW9M0IiggDzRUx+VZHm0DIiAy0yuk53SRacL6UQYBJnHj97G3NoO4A7ktX0x7yKTnpMiDJMnKVF9AysP2A84EQ0MRW0CqWLIz5xPkM3K1kxi2T8GxrZH31PDuMT3keU09iH/vkRO7sbSw2M1zMo4+JA89Ckl7NPjKxus2yuZHnxlmB/3HopN2bSCl/cdhvJM47OyS7I0X16SBJzX0ugDrLaSV9JZ2CJuvidut6MNUmyYGtg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=1m6VwGvU2i9VkH2lxzW589AnGPUyCBiVKofI75V/BjI=; b=B3qj0BErg4IR8vjGmZCctwZXVkyP+sSm8Jikl/lAB7T07CiDyLK58qbI9QxxToTkSLnrIBcGOvMu6AX3qB8016hiY/AKLtOhBnDatL9eTzLey0EWsar8RPk+jR3vpqqnMWLVbrLqbaVXgC0PI6dnLH+2oNXuVoijmiZya7isAe+VpTVySCTIaQFnqcyjtzOcyXQpXMOlGUH0McCsv9AzTkMhDS+QvXN/zJP0QA1SZFKPR+oHikH2VsFMg4rgFTWxyDTtR8TDkc7gGhv09gEtHBPlT0hozEyXJ/opF2nTIOgGtVg6YBKgsDty9CZWxhOrt10nq7fJJRWW3dmb/Q4G8w== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=intel.com; dmarc=pass action=none header.from=intel.com; dkim=pass header.d=intel.com; arc=none Authentication-Results: mx.microsoft.com 1; dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=intel.com; Received: from DS4PPF0BAC23327.namprd11.prod.outlook.com (2603:10b6:f:fc02::9) by SA3PR11MB831931.namprd11.prod.outlook.com (2603:10b6:806:589::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.522.19; Mon, 19 Oct 2026 19:54:00 +0000 Received: from DS4PPF0BAC23327.namprd11.prod.outlook.com ([fe80::6fbf:c112:d0a8:f1a8]) by DS4PPF0BAC23327.namprd11.prod.outlook.com ([fe80::6fbf:c112:d0a8:f1a8%5]) with mapi id 15.21.0522.017; Mon, 19 Oct 2026 19:54:00 +0000 Date: Mon, 19 Oct 2026 12:53:56 -0700 From: Alison Schofield To: Richard Cheng CC: Davidlohr Bueso , Jonathan Cameron , Dave Jiang , Vishal Verma , Ira Weiny , Li Ming , Subject: Re: [PATCH v4 4/9] cxl/region: Calculate peer distance only for reused targets Message-ID: References: <6ac7f8fae75f7cd29b5d530a552aec2b6c6169b5.1792263750.git.alison.schofield@intel.com> Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: MW4PR03CA0011.namprd03.prod.outlook.com (2603:10b6:303:8f::16) To DS4PPF0BAC23327.namprd11.prod.outlook.com (2603:10b6:f:fc02::9) X-Mailing-List: linux-cxl@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DS4PPF0BAC23327:EE_|SA3PR11MB831931:EE_ X-MS-Office365-Filtering-Correlation-Id: 50562ccd-c9cc-4e13-a0a7-08df2e1ab7dd X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|366016|23010399003|376014|56012099006|4143699003|11063799006|261009223027099003|10067099003|22082099003|18002099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DS4PPF0BAC23327.namprd11.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(366016)(23010399003)(376014)(56012099006)(4143699003)(11063799006)(261009223027099003)(10067099003)(22082099003)(18002099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?6DvTNLNL7J+QfAaoRjcOgZKMt1KiGfMD0ZctBnY1YSnEWWLEan8kAt3/KYij?= =?us-ascii?Q?wEOX2iFrnU0SzAjnrKYjgCXcpD5BUFSXHQgRTWHFDtY+Ydy1wwykLWthZpWt?= =?us-ascii?Q?ucfpZUpoQJzICOf5AeUO12Nf0+Hg+zhC857XWMKi5TuaczjDcHySggQ91efh?= =?us-ascii?Q?JWocZMYA6O6Qvk5Vlh2VM6lsfxP8PbTp/QWu/CJnYjgPzvEPupZab0sF+3/c?= =?us-ascii?Q?CUQR0DVj/TNWRj9u8dZ9ycYD9twte3apGAxBR9WBZ+8fSnOh49isIhn8N9AH?= =?us-ascii?Q?DxrYJsRRERNyiY57XG6NRloPLrgFmkB89SmLNVwJK7cJxhyQwuq/JsNsdJEI?= =?us-ascii?Q?1+5Wh7EyOk6yFqMcVLHmNFbSfgeY5zfqEAKRA0mghJHIfbKwiLnUa5AXNMLe?= =?us-ascii?Q?SmwmNl4H91cbvptx56L9uhmuzu5O2wcg8VcRIzVWDjFJla9qxmMOUA71cRba?= =?us-ascii?Q?TRlS12bQMY4S4h9Suox6zkbO6nirE0zTzn6K3gZ4pwDLtAdw8Y53EMsFXXDT?= =?us-ascii?Q?kS0InNZpnCwI4obag2bJrDe10mAhKGIJooF99Xxs+MhPDnYMjHU25/YV9x/e?= =?us-ascii?Q?24mD+UBiVLVa6qOLIm/fV+16RcCOYSGs6KTtPLJW/DGPPJPwIyrwYpfbK9vm?= =?us-ascii?Q?9SqXUWO5eLXpysvUDXxsI94V7ZO5Ud0+qaXWVHMLOhCYv6bfWLindTYl48oK?= =?us-ascii?Q?MWX3JWiR6ao3VbyjDhgZ0bbFuSOBRl/gbQQvHY1dJm7ewqTaxqmevw0cfuIZ?= =?us-ascii?Q?GiKAjjzWl9opcvyIZz+vNZRtp0KPdn9xOdCeZIadNnEVW5SImNzvVENzTKJs?= =?us-ascii?Q?LeLNTDtfJGeug2UQ7dhIsXlOFaJ7TnYCV08STfWRUdbZEg8F6x69hv1YPUBB?= =?us-ascii?Q?SL9crpHyZeOm+QGtNVsVJ8q0/B1ei7rsxfv3fEqKtZhY5qcmpG7DfGWwkvaq?= =?us-ascii?Q?zq9CCHsU4WiXb28jFv6E2avHCTj0MgrtG5QcPfofOPYDPOt6VxBV3xTxNOTM?= =?us-ascii?Q?9att09U0D8jhRtJ65evJdMXGBd3tq2EqMiVnagWFj/5EdIM4tGYPGmYihd/z?= =?us-ascii?Q?477tDfq06egBsSyWuNcjh8yw5TSQEeQ31RBrepjvjDDc7TctblwTa4g/OoP4?= =?us-ascii?Q?WAtb1kxpQHfzd+rtd1n+nBpDAZ27gTBiG75y9USDqJXxcHPLd/GUBLKmjLgw?= =?us-ascii?Q?OYrfX3Q5wfwNGs4txPCahxtjeccbq1kn2SBAyiSaj4vZwkSFENnad+1fijQa?= =?us-ascii?Q?MRZvqZmd34H4n+rI/kq3nHlUQ3NYoxUTlbMYoLfTVKdAHUh9lKfqA1vAdJhm?= =?us-ascii?Q?924NndiwR7OSZU59HQ+dFJU0FUTXKlp8ZAVq3ElYyZZgxaDu+EwUTA8ueHcA?= =?us-ascii?Q?iBieqNeTPmrYr9LdAz26EEaGyf97CuFSYKn2EZBAMvyj3viBDuMIQtKC0i8E?= =?us-ascii?Q?YDA0kHb1RN98yCZI7M6cBGvQdpUHYJCSbuWAspL5qzb1YMhVQxfiBrUccJM+?= =?us-ascii?Q?BNN3aw2cx44cBw8AZsj8R2hTNKVCvFclYazsv85f2zQGNnwlp5whjbs/F7eu?= =?us-ascii?Q?nXyCD/kM+BdkddiS9gHrOwyPXp1/eyVL6sFynojJdkSTgn8X1jeoO0aptOQF?= =?us-ascii?Q?bfMv99BW/0737mMSaQfhmThGU67/Jxg9FOSlsu6/gMUAkzoV8D8hwMQtC1s3?= =?us-ascii?Q?d/TZegAhDWBpGoEAWLwsUlxILo1J5B9TWFdLp+GLHYhDn7HXPa+uqKBnInWe?= =?us-ascii?Q?0EcZ+r9F+hsvZd+o5NGbT7iEW38V18Q=3D?= X-Exchange-RoutingPolicyChecked: bVUGMgXh5AUiPd4Yp798pRIPy6X5d/oeuqygowK3Hxcbtnz7/Tz/VCon52fkuQSbtt+26qJn7jb55c5mpIpPy/zIUl7i7TUTf7sTft4LygoAjm3sM6p/OpbZViOE/jm7Y8stONT7UXklmnV4i59NoBVcJua+uhSmkb6NN1ikz7O1qnYfdQkSJTKFYSzNsjA+TZ1EerWroxtORIHZWRmEFO8jn9VV84v+K0ncDjrsEZlqw/scQxXCa8TUO0/e0h48crMlRWJ1aAyDxJsxMXHXQ7DIa5JCtHs5dUUvEAqH+XXvHBADv9ORCSZW8LLv530Sy1LIRTj0WTsGsTUlq95QDw== X-MS-Exchange-CrossTenant-Network-Message-Id: 50562ccd-c9cc-4e13-a0a7-08df2e1ab7dd X-MS-Exchange-CrossTenant-AuthSource: DS4PPF0BAC23327.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Oct 2026 19:54:00.1883 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: cUwsmxsrNOyRj84JslEIQppoP/4E7WnAkI/qqO/YzI3VIwoVzd4ggL672QkaOj5ko16dbjBCzsIz6Z3DpMH3o2dNZdvnT7VXTT/a4Iaq02k= X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA3PR11MB831931 X-OriginatorOrg: intel.com On Mon, Oct 19, 2026 at 03:31:29PM +0800, Richard Cheng wrote: > On Sat, Oct 17, 2026 at 12:19:49PM +0800, Alison Schofield wrote: > > From: Richard Cheng > > > > cxl_switch_port_setup_targets() calculates peer distance before > > searching the existing targets. When the endpoint needs a new target, > > the calculated distance is never used. > > > > Move cxl_port_peer_distance() into the matching-target branch, > > immediately before check_last_peer(). This avoids unnecessary ancestor > > walks and per-port region lookups when adding distinct targets. With cxl_test, the x8 region in cxl-region-sysfs.sh reduces calls to cxl_port_peer_distance() from 10 to 4, and the x2 auto region from 2 to 1. A misordered-endpoint test confirms that peer validation still rejects mismatched peers. > > > > Signed-off-by: Richard Cheng > > Tested-by: Alison Schofield > > Signed-off-by: Alison Schofield > > Hi Alison, > > Really appreciate for the testing and if we can, can we add the testing result > in the commit message demonstrate benefit it can bring us ? Added the above for v5, taken from: https://lore.kernel.org/linux-cxl/atLBlibv3kbT7xv5@aschofie-mobl2.lan/) Let me know if you want something else. -- Alison > > Best regards, > Richard Cheng. > > > > --- > > drivers/cxl/core/region.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c > > index 4ab5a1d025a9..8bfebe3e1025 100644 > > --- a/drivers/cxl/core/region.c > > +++ b/drivers/cxl/core/region.c > > @@ -1485,10 +1485,10 @@ static int cxl_switch_port_setup_targets(struct cxl_switch_decoder *cxlsd, > > } > > > > if (cxl_rr->nr_targets_set) { > > - int distance = cxl_port_peer_distance(port, cxlr); > > - > > for (int i = 0; i < cxl_rr->nr_targets_set; i++) > > if (ep->dport == cxlsd->target[i]) { > > + int distance = cxl_port_peer_distance(port, cxlr); > > + > > rc = check_last_peer(cxled, ep, cxl_rr, > > distance); > > if (rc) > > -- > > 2.37.3 > >