From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from NAM04-DM6-obe.outbound.protection.outlook.com (mail-dm6nam04on2060.outbound.protection.outlook.com [40.107.102.60]) (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 9E763197A8B for ; Mon, 23 Sep 2024 10:34:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.107.102.60 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727087643; cv=fail; b=hIxkhU7XZjcegkS/y340cDUs59u8SKgkDoJ8YPcKpYwylu2tEq0TuFDG3yXc2KWI9L53OxL1hUySEmn7tu7q0dhpnTDNNU8iPU9j421hcuRQ1RrEHudTs/wfQpVM5sahl2DrQ5A7Rf3u2gX8YPbpW+gS6iQbo5h5Vp8gW5wMYZ4= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727087643; c=relaxed/simple; bh=qidizbp+oSWWPPfLK1CnC7+ybZsqcKhMWnCceWwap50=; h=Message-ID:Date:Subject:To:Cc:References:From:In-Reply-To: Content-Type:MIME-Version; b=aqyg50QnLwwk2wjZMMWg72RGA8XGheXKCxuKI+yPi/Vc+ypEOPKqklIN/yWHoT/R80cWl9EAPBWnS9Gwk3wZBGv39mnPVeOLS3qDrfES+0Lnuap7WK7TKQTfoLLRS6xL7uxgDzwii9gopXILAPvdUdhMRCWDrEx1+nsUVxkD/9M= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com; spf=fail smtp.mailfrom=amd.com; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b=2hSvwm3h; arc=fail smtp.client-ip=40.107.102.60 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=amd.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b="2hSvwm3h" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=PAk9VAojByrWd41B4t1XsTJbF+I+G5yuiR+gOB0tUz3iXq5puBEP9JmHg5hDWJjUHCE/e7RnumBunVFfC8rbCyq28n/E0UAUCNaiIvrmprO4j7jLfsdtWCxYFmlg10e2zd9+CyiuXI60EF7BVBr6OZOi20AlSEUPIvkao96h7RXsIvNMzYAbc1x/egWeHT3x/l6HswsUq607d70oeRl5CQtlckcDzwbBA/Z3UJVhKlIfCPNzcEmT3wy7vZEBNTTUWZ926Dc1h1XsTYRSGcehtw+Gw3KyI96oHXMm8GUgoYM37wmt4TSX4aR5gZ+RiayZJsid6BwrVfaxA9OoDLxQhw== 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=irfb1lsE/USIfI+iqvbE2whCoJoienBUb6y7E3qLnPQ=; b=cjW6xieOiKfjHWx9bcdW7fsbCHPf1k4CF8ZMufTqw4NwKUXgqAyKOV8BmB+Kf0UFOHk2mQUsYTPZQvLMBZyhGVcaS4T8lfMRL2ZZ59A+gTRrbr317SbYUeNGZyxFydCCjlT4yweGVjg+vCoFPNX+Gct+2bJRSDIIeynGhAYD36nt6Ez8kSHSalRqFFFAU4SCMAjQX9wBDGKGyXi1DeJPm15cxPnnOdDl+0t2+pHeVJ/H9i3/WzBc5KI+rLxjcgdc7K56LQVMc7m9XjxO6leQg6fTbJDtvaNh8FcwcaRGFDCNgvrng4IbRIyJdHPURDnR2vtc7/vGdtLQ/Q+xLoiorQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=amd.com; dmarc=pass action=none header.from=amd.com; dkim=pass header.d=amd.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=irfb1lsE/USIfI+iqvbE2whCoJoienBUb6y7E3qLnPQ=; b=2hSvwm3hr3A/3GJxmGnHKEEt5Dbbb+PYAnLMaMcH1cHxc0dZ1byeJoDqn216LCaOb6FTF+8RkdwVNOedOgA45+23bShDMj0o94lsBV0Gu+wnxmtlK4h1SkGkX2R3x2ka2isWTX0/YxSDu16pWy37V9PKwrXowm21uTTWwwRbWe8= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from PH7PR12MB6588.namprd12.prod.outlook.com (2603:10b6:510:210::10) by CH3PR12MB7740.namprd12.prod.outlook.com (2603:10b6:610:145::8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7982.26; Mon, 23 Sep 2024 10:33:57 +0000 Received: from PH7PR12MB6588.namprd12.prod.outlook.com ([fe80::5e9c:4117:b5e0:cf39]) by PH7PR12MB6588.namprd12.prod.outlook.com ([fe80::5e9c:4117:b5e0:cf39%4]) with mapi id 15.20.7982.022; Mon, 23 Sep 2024 10:33:57 +0000 Message-ID: Date: Mon, 23 Sep 2024 16:03:47 +0530 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 5/5] perf/x86: Relax privilege filter restriction on AMD IBS To: Namhyung Kim Cc: Peter Zijlstra , Ingo Molnar , Kan Liang , Mark Rutland , Alexander Shishkin , Arnaldo Carvalho de Melo , LKML , Stephane Eranian , Ananth Narayan , Sandipan Das , Ravi Bangoria References: <20240905031027.2567913-1-namhyung@kernel.org> <20240905031027.2567913-6-namhyung@kernel.org> Content-Language: en-US From: Ravi Bangoria In-Reply-To: <20240905031027.2567913-6-namhyung@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: PN2P287CA0010.INDP287.PROD.OUTLOOK.COM (2603:1096:c01:21b::16) To PH7PR12MB6588.namprd12.prod.outlook.com (2603:10b6:510:210::10) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: PH7PR12MB6588:EE_|CH3PR12MB7740:EE_ X-MS-Office365-Filtering-Correlation-Id: 6595142d-d060-4fb3-ecc9-08dcdbbb3a77 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|366016|376014; X-Microsoft-Antispam-Message-Info: =?utf-8?B?anRFR0dwbUtyWllpc3MzUDQ3K3RVT2JNOTFaRnpobGFXUzFpbVM3aFUvM3Uw?= =?utf-8?B?ZXowS3FJRExTbTcxVXpnU1U0dVluVFRibW1HRkRMTTZtR2RONXNSVUJ1V0tx?= =?utf-8?B?VHFMdElIUEpHK3YxaGNiUVRVWFQ1a1dsTG50NkUzUHNabFpYVTJWU1d1M3BX?= =?utf-8?B?c3k2S1IvYlJKcUt5alNwY1h1TmZPeHJGaldvc1Bkd09zNHgrbTdUbnp6emJt?= =?utf-8?B?N1h5QTBkYjZYYlZjMXM0eStjR3ozcnRabjBidGlPMS85Lzl2eGtUdW5KK2Zn?= =?utf-8?B?elU5RCtjQ0s1cUZwS09pcXQ1ZHYvQTBGRjBlck95bGE3UnVOVm1zOEs5a003?= =?utf-8?B?YmV2cUVsVE1iOFRrbEpMSFFsZGtsVi9Pd2RiZnRiOURIcHVFQm81b1FLaUsw?= =?utf-8?B?YWlzM20vaTBGc2JkejFnaEd5Z29YTkVNRnRrL3R2OU1EN2tzK0VVQXZoTlNy?= =?utf-8?B?d0tyejFGVnpwSmcwUUQ5MklqSHE5UDd6VGZ5OFBrZjJZNUd6SmlEaFlkNUdF?= =?utf-8?B?SGNLWUJ2L2RZYzBqTjk0QnVhai8rQ0szL0lCcFVCL2pza0FGSDUxK3IyM0ZX?= =?utf-8?B?MmRxd3p1S3N5ejgyMlpsd082U2ZvY1Z0c25QdDhaUmVvMUpYL2dYZzlEVVEy?= =?utf-8?B?dTBjeXVIVGE5ZlRvZ3lYUldiWVFzN2l4Ujc4TnRzZHNJMThDaTVuczVpU0R4?= =?utf-8?B?OTlDQnRISFdDSEQwSVRwckV1ZkFXNm91ekI5U3BuSURyeWh1U0dpYnIxakd3?= =?utf-8?B?ZGV0MDQrWWR2dlZGRGovbFU4Uk1MbCtOczJqMTRNYjRjS0NKNDFXMFlLMWcr?= =?utf-8?B?VUN4WWdYVG1tUThCUXdIQzNYTlZUVHZQaTNORUpVOHlWOFY0YlhkQlRzVjYy?= =?utf-8?B?OXFkamlFb0M0MFdqYlU5d2h1UUNtcnFYRzQ2TXB6bFg4YlVjem5TaXhDUFlo?= =?utf-8?B?Q1ZBOGFkRkF5S2VTbWkzbkdsdUI5TlU5eXNrclJhenZBTkJPUTZrbmV6RXBN?= =?utf-8?B?NVhzbUJrbFFaRXg2am9FVlNYb2ZYL3lzbTRwYnRyQUk2cHQzKytnT2NxM01B?= =?utf-8?B?eEpaVFF5djlqTFlNdElUdG9pZVFjTldnNGZKWTkvLzdLRUVOV2prYTNleHND?= =?utf-8?B?c01kUktaUlhFY0ViNjJkc0JQZ2RjS3BMaS90bStjL3VBQitsWEp5c2NyNWRL?= =?utf-8?B?anBIMTl1VVc4dnZCRG5tNGZJbTBjSHdoRTlFMnhONzh4WDFacXV1MFlQamJj?= =?utf-8?B?aS94VnNJK3NJcmdxSE5nalVYQUR4WHpHZGZZeHhkSFJkS2FGUlVrMGFwcVlj?= =?utf-8?B?ZjdvcGtmTS9RK1lXcndIREVoMDNod0xZVHc4K1ltenljNzljaTJYUnIxVE9Z?= =?utf-8?B?TTVmVVJjU2ZLZ09JYWdEQ20vUEJ5YkVMc0w5YWEzaEZrTWk1enRCdlJwbHlj?= =?utf-8?B?bW1kSmY2NEFsWkhTTUZvK1NQbFBzTTVkS2xRaUc0VU5lK2pTU295M1ViaVFa?= =?utf-8?B?bUUzQ1grcUtnWU9JdVVmU3hDSGo1c05YR2JQWmdtR2R2VU1yQWlNTkdXNVpN?= =?utf-8?B?L2UySHN6ZlppR0JCdlVJYW5DZGo2WWRlU2hFSXMwblhEZUJEM1JDejh3b2ti?= =?utf-8?B?d25jR2ZXSkFwbnFiR2pWbWtjcHQ1NFI1eDRScTAxMUViZnNEbFh2OFlPeUV2?= =?utf-8?B?T3VnWUoydXJaMmg0U3NDblVtSDJFWlExdWxkNjllY0JkQXdMWTZhMkRiTE95?= =?utf-8?B?dzhYNjJUaVJZV1dNZHdGYlU4VEh4UFRrelFjeitnZTFYZ2UvZ2RLUlh1YklK?= =?utf-8?B?RVlCNFRFR1RLN2dDMnAxUT09?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:PH7PR12MB6588.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(366016)(376014);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?R3VJTy9CTjFDYk9LaVdtNWFVNHl6bWxEa1lYajk3RjhCeGJrQ2R1TFNCVU5O?= =?utf-8?B?eEMyQTRMTVcvTlZBSGVBaHpkcXJlUWJvUHQzQjVtdmVxVHhMTGNOeHBKMVN0?= =?utf-8?B?N2ZvdW81VFo3REVaUnIxVnpjeUNrbDg5RmRYTmRBdmd2ZkkwdUZuNStzRk02?= =?utf-8?B?Qy9kMnRkYmRVZDZXcnN2N0g1WVo5cnNjVWE1QnBTempNSzlPdGtYU2w5WW00?= =?utf-8?B?SEIyeXNqL2Z6ZHNlc3dTTzhwZFprYkUyZWQvS3AyenpoeXI3Mk1ISlJxWUJx?= =?utf-8?B?UkhweW4vanVGVU4vSkFoMURRVFFzZG5QT3g2OFI0VFhxeCtmS2tHQWc0L1hh?= =?utf-8?B?VTBPVlNjWDVkcnBLZzNxb0dyUTBGQnlNQlo4S0VaOGhNVmdkZk5ZZHNJdnkz?= =?utf-8?B?NFEzTnVjUmFRNlpCem4wQ0NrY1JFQXQ1bVp0UUNad1VhTkxuNlZ0SzFLUlVn?= =?utf-8?B?TWowUUZEVS9qb2ZlZ3lvYUh5R3MwamhhMzdSc2V0eFNqVHhUQ1RWL0dOZ1Rw?= =?utf-8?B?R08rWFNzTnFwN01WczZjZ3MvY0trQ0Fva3lmc1VCRVIrNzA0QXE5VTJFTkk4?= =?utf-8?B?TEVDTElZaE1Ub2ozTXZobVNPQXFGMy9DcmpmVFNOc0lrOW1xdkptM04rWDNm?= =?utf-8?B?SnpVVVEzaDRTNFlFR1psUGZKcXM4K1ozY3FyMWhyNExTNnh0SU1SaXFzRjhk?= =?utf-8?B?WTZnMFFFMWJVMUZzVXZTMHdmRnFhbTNHZmoya1Vld0cyMll3ak5IYVZJNlFV?= =?utf-8?B?Qm9HMW10b3crU2NHcHA2L0p1K0h2KytaZkg0Y1hQMUNhbDFubHc2aXp0ZWJN?= =?utf-8?B?YU1venEyYk50QnF2T0xqL21YTHhubVp0NDAzUUFnZlVCTTY1eEhKUDRRbFJv?= =?utf-8?B?Z254K2Y0RkVsSmpqOUlmSlh5bjNId1M3UmM5UnpqNktXTCtwWk1TREpCblYz?= =?utf-8?B?OUxyRVVEV1NBWWgvdzJUYVNxNXNrSElheDJ4aENwSk5reW82RU41K09PZVIv?= =?utf-8?B?TjloMDJySjJCVXFKSjA2LzRPQ3B1NkpxaUs4MysxbDAzMmRXejZzSWczZDJ3?= =?utf-8?B?Rzd1WXdjUnBEUzVDQlVJelAzWjlEN0NyaGpjbjM1UnFENDFJMWJUYjRKTFlC?= =?utf-8?B?bllBWlNBOW9OU0krd2dXa1ZIdS9Senl2VUZVaURLY1JiK2p1Q1I1aXhNVERZ?= =?utf-8?B?R1FnRjZqSTg0SDdMZmkyYlhvTjJ3bHFHb3BjcGNRTERNR2tGS0RJRVBxdmxO?= =?utf-8?B?eEJCcnJGbjlERUdZK3JBRlN5bUNFUlcwQ2tEV2xwZFVLUEhoWjBOa21Uczly?= =?utf-8?B?V2dZWks0TDk3dCs3UlpSRTVSWTl1S0dyUk5wblcvcmNzZWEvV1hFVnl5aTdJ?= =?utf-8?B?K1F5eHQwTEhNQkRFdWwrZURYK3BwRU52NTk2WUFGSUNJNWZsWmhNdStGMnBh?= =?utf-8?B?WGdMUFFHOXNlT3hqMDdRZlovaURzT1pUckpscGVNaGlZdThGNittcW0xSmRX?= =?utf-8?B?K2hGT0FEbzhvMjZPcFBSL1liUzRkdzNmL0Vxa0VLdUVnRmNSemcxcFVFeUtq?= =?utf-8?B?cWhVbzZKT2RqWC94VVU3R3VPU1diblZ2cHg3QTR2dkRoOGI4bXhibzNBRWh2?= =?utf-8?B?cUozZXVUVVlOWUk3djhUano3ZW12RXNVd0tLTDEwWFVoM3FpSHpYZ2JKYkpP?= =?utf-8?B?ajNNci8zYkhuUzVkQ2VEeUE4eFl6RXI2NHFkTzRCamlEQlVVY0JwR2R5NSsy?= =?utf-8?B?c1E0QlNSZDVqa3FXdzN6L3lSZXRhbnNsUzZwVytiUS9UR09XK2pzQW1FdldQ?= =?utf-8?B?NW1jaWc4RTJ5dzNQRm1PMzdWOVhoc0tGNnpsbExWdDl0MTNzV2hxYU51WHpF?= =?utf-8?B?NmJnNllzUWlIVGtWQUl4SnMxKzh6QktCN0I1ajBUNDN6TWZldll3SlAwUDlm?= =?utf-8?B?L29mZEVkd2gyRTFnSGJmb1Q2SzhwN2cweVVlUGg5OXgyOWpvRVlBa2RmL001?= =?utf-8?B?RTFrTkJ1aStHcjVaNTRMMXhXQWtwN0dtejlsSUZtZjdrNTFkL1dJRHhjelUw?= =?utf-8?B?S2trSjJ3NWlQZmZXczU3d1RqU09jbGdpemFnMWxFZEkwcTNZQnoyR1VudDJF?= =?utf-8?Q?CclzBeIZ5WKbeBrungfq/Pahq?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6595142d-d060-4fb3-ecc9-08dcdbbb3a77 X-MS-Exchange-CrossTenant-AuthSource: PH7PR12MB6588.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Sep 2024 10:33:56.9840 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 2qWKYRqr/rOJ5wlATjhLKZ6Kca7Mf8b8VAX2OwZe7B20rOqP4AelpXIxxH7CCLCkH01kDKWXKQL2ISkQnzmedw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR12MB7740 Hi Namhyung, > While IBS is available for per-thread profiling, still regular users > cannot open an event due to the default paranoid setting (2) which > doesn't allow unprivileged users to get kernel samples. That means > it needs to set exclude_kernel bit in the attribute but IBS driver > would reject it since it has PERF_PMU_CAP_NO_EXCLUDE. This is not what > we want and I've been getting requests to fix this issue. I'm working on some IBS improvements that impacts this change as well. Is it be possible to hold off this patch for some time. I'll try to post my patches soon. > @@ -1111,6 +1127,12 @@ static int perf_ibs_handle_irq(struct perf_ibs *perf_ibs, struct pt_regs *iregs) > regs.flags |= PERF_EFLAGS_EXACT; > } > > + if ((event->attr.config2 & IBS_SW_FILTER_MASK) && > + perf_exclude_event(event, ®s)) { > + throttle = perf_event_account_interrupt(event); > + goto out; > + } Throttling can give surprises when the sample period is very small. For ex, $ ./perf record -e cycles:uh -c 192 -- make [ perf record: Woken up 52 times to write data ] [ perf record: Captured and wrote 23.016 MB perf.data (705634 samples) ] $ ./perf record -e ibs_op/swfilt=1/uh -c 192 -- make [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 1.608 MB perf.data (19 samples) ] It seems like the IBS event gets throttled (and disabled) before the cpu get a chance to go back to userspace), hence we end up with very few samples. Thanks, Ravi