From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.11]) (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 05CE2335067; Mon, 16 Mar 2026 16:59:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773680343; cv=none; b=hcI348v83o0BGdnXLvTA9W/BDqTGp0NKo2e60rFyHVnoX7hk6cG2HzK3i4vs8IWLT9IULkzq+Y7qCtQ31VOb/ER1rIXwb+0YlgzAALQvWtowqOFda32t0Jl1ypTi/7s8BNNAQK2hjYUbkcrxYb62aqSrP1963nfkwQECxk1HDcA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773680343; c=relaxed/simple; bh=6kyhGMclKhoByEDQ31nH2QKzOsdm+RXquTaL6ve8oK4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=bCwxBQbKDVDswkFHjBEjTk+xf39neOq3wnqm0WKGywgHvmKD3Vi/aH8HYxHNOzaWU3zdcLo2PWUTZA41Mvr3uuNe2zETpn+0OwcphTs8mo2NwMYF8lqlhOFfQR/SV2hmx+8DK0H1AP5DklxE58SbGaySBy+9tBqghKqgyXEZxhc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=YXpx1l3m; arc=none smtp.client-ip=192.198.163.11 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) header.d=intel.com header.i=@intel.com header.b="YXpx1l3m" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1773680342; x=1805216342; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=6kyhGMclKhoByEDQ31nH2QKzOsdm+RXquTaL6ve8oK4=; b=YXpx1l3mRs7ge6WPTFotMsxZLUGfexCurhCFURv6Y8jv+gew5XJbrhYq enoTYp7brlLt/Zg8TK8Dnhfdo2z1VVWGFakXS92V12cChWmNFR9Ei979e vbrzhWI1PGiZaBC1XmC2fcL54Z1B9Ece2sE87pFQ9IN4h57tixJuaZHwT A827/CDWMsrk7xv/jRlTw+ZE9h70a7yHBtr5dF8RzfZjIIWxBCeVF8eHl HnEZPGjfqBNyNPRWhmmHT/FSzqDyAPA6qFr3cYxEBNIZrwUAIoxDGBs6a FdqAGlUfY1lU6RXaYUGw+Vi1TwBTFhLn4c2TtN0ehguWU/B3Lbso18cl2 Q==; X-CSE-ConnectionGUID: Rg+n4+7zTi6hg85FS5NN8Q== X-CSE-MsgGUID: Jwu6R8ePTIKVINLqrgaNkw== X-IronPort-AV: E=McAfee;i="6800,10657,11731"; a="85331353" X-IronPort-AV: E=Sophos;i="6.23,124,1770624000"; d="scan'208";a="85331353" Received: from fmviesa003.fm.intel.com ([10.60.135.143]) by fmvoesa105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Mar 2026 09:59:00 -0700 X-CSE-ConnectionGUID: bx/1BhI+Qs6n6sP4JdTrOw== X-CSE-MsgGUID: BCTi08vuRmmhjDQYUT3ukw== X-ExtLoop1: 1 Received: from unknown (HELO [10.241.241.35]) ([10.241.241.35]) by fmviesa003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Mar 2026 09:58:59 -0700 Message-ID: <8f257e9d-6a39-438c-9c41-6f68e2ef6d62@intel.com> Date: Mon, 16 Mar 2026 09:58:56 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH V4 3/4] perf/x86/intel/uncore: Fix die ID init and look up bugs To: "Mi, Dapeng" , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Ian Rogers , Adrian Hunter , Alexander Shishkin , Andi Kleen , Eranian Stephane Cc: linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Steve Wahl , Chun-Tse Shao , Markus Elfring References: <20260313174050.171704-1-zide.chen@intel.com> <20260313174050.171704-4-zide.chen@intel.com> Content-Language: en-US From: "Chen, Zide" In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 3/15/2026 11:53 PM, Mi, Dapeng wrote: > > On 3/14/2026 1:40 AM, Zide Chen wrote: >> In snbep_pci2phy_map_init(), in the nr_node_ids > 8 path, >> uncore_device_to_die() may return -1 when all CPUs associated >> with the UBOX device are offline. >> >> Remove the WARN_ON_ONCE(die_id == -1) check for two reasons: >> >> - The current code breaks out of the loop. This is incorrect because >> pci_get_device() does not guarantee iteration in domain or bus order, >> so additional UBOX devices may be skipped during the scan. >> >> - Returning -EINVAL is incorrect, since marking offline buses with >> die_id == -1 is expected and should not be treated as an error. >> >> Separately, when NUMA is disabled on a NUMA-capable platform, >> pcibus_to_node() returns NUMA_NO_NODE, causing uncore_device_to_die() >> to return -1 for all PCI devices. As a result, >> spr_update_device_location(), used on Intel SPR and EMR, ignores the >> corresponding PMON units and does not add them to the RB tree. >> >> Fix this by using uncore_pcibus_to_dieid(), which retrieves topology >> from the UBOX GIDNIDMAP register and works regardless of whether NUMA >> is enabled in Linux. This requires snbep_pci2phy_map_init() to be >> added in spr_uncore_pci_init(). >> >> Keep uncore_device_to_die() only for the nr_node_ids > 8 case, where >> NUMA is expected to be enabled. >> >> Fixes: 9a7832ce3d92 ("perf/x86/intel/uncore: With > 8 nodes, get pci bus die id from NUMA info") >> Fixes: 65248a9a9ee1 ("perf/x86/uncore: Add a quirk for UPI on SPR") >> Tested-by: Steve Wahl >> Signed-off-by: Zide Chen >> --- >> V2: >> - Fix the commit message to note that spr_update_device_location() is >> used by EMR, not GNR. >> - Rewrite the commit message for clarity. >> - Add a Tested-by tag. >> >> V4: no changes. >> --- >> arch/x86/events/intel/uncore.c | 1 + >> arch/x86/events/intel/uncore_snbep.c | 13 ++++++------- >> 2 files changed, 7 insertions(+), 7 deletions(-) >> >> diff --git a/arch/x86/events/intel/uncore.c b/arch/x86/events/intel/uncore.c >> index 786bd51a0d89..e9cc1ba921c5 100644 >> --- a/arch/x86/events/intel/uncore.c >> +++ b/arch/x86/events/intel/uncore.c >> @@ -67,6 +67,7 @@ int uncore_die_to_segment(int die) >> return bus ? pci_domain_nr(bus) : -EINVAL; >> } >> >> +/* Note: This API can only be used when NUMA information is available. */ >> int uncore_device_to_die(struct pci_dev *dev) >> { >> int node = pcibus_to_node(dev->bus); >> diff --git a/arch/x86/events/intel/uncore_snbep.c b/arch/x86/events/intel/uncore_snbep.c >> index 9b51883fd6fd..421378f681d7 100644 >> --- a/arch/x86/events/intel/uncore_snbep.c >> +++ b/arch/x86/events/intel/uncore_snbep.c >> @@ -1459,13 +1459,7 @@ static int snbep_pci2phy_map_init(int devid, int nodeid_loc, int idmap_loc, bool >> } >> >> map->pbus_to_dieid[bus] = die_id = uncore_device_to_die(ubox_dev); > > The "die_id" variable is not needed any more after removing below check, > please remove it. Good catch, thanks. > Others look good to me. Thanks. > > >> - >> raw_spin_unlock(&pci2phy_map_lock); >> - >> - if (WARN_ON_ONCE(die_id == -1)) { >> - err = -EINVAL; >> - break; >> - } >> } >> } >> >> @@ -6420,7 +6414,7 @@ static void spr_update_device_location(int type_id) >> >> while ((dev = pci_get_device(PCI_VENDOR_ID_INTEL, device, dev)) != NULL) { >> >> - die = uncore_device_to_die(dev); >> + die = uncore_pcibus_to_dieid(dev->bus); >> if (die < 0) >> continue; >> >> @@ -6444,6 +6438,11 @@ static void spr_update_device_location(int type_id) >> >> int spr_uncore_pci_init(void) >> { >> + int ret = snbep_pci2phy_map_init(0x3250, SKX_CPUNODEID, SKX_GIDNIDMAP, true); >> + >> + if (ret) >> + return ret; >> + >> /* >> * The discovery table of UPI on some SPR variant is broken, >> * which impacts the detection of both UPI and M3UPI uncore PMON.