From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.7]) (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 ABE763A1BF; Tue, 11 Jun 2024 16:49:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.7 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718124597; cv=none; b=PW5i9MopJuCw027HJpJPrUvtRDCyVI0kFkvJ5g6AD8WLrv/k6fwY28QfHkXCZ7QWtQkUuXyrumbxMcZ5AGbDqy/7ZAEsOdrkMamje5T6o8hlixGVmgsZZkV5TbbPJKVRCylRMFmwKYgls2BGJ2bpK+ZXvgA41G1ONE0cM2TgOAE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718124597; c=relaxed/simple; bh=1v047t35c6qLm19msLAzWgPRd+2a52vL96fVRO7TAkE=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=JtS3AyaE6UemIpggn537lVN16oWvpBEXXz4dov0NxnMH6R3aOY/EuB5taSX7NRpkRN7igl5XKHB83f6TlpPieoI1eEO4YEX5YbA0oKhXIivtqI3Ycx2oVV19R6HKP3s6f2i9QuBh0gZe/xExTYdedfrb8jl9lGVO+3ZlaYC3rtY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=mbcGSzo4; arc=none smtp.client-ip=192.198.163.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="mbcGSzo4" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1718124596; x=1749660596; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=1v047t35c6qLm19msLAzWgPRd+2a52vL96fVRO7TAkE=; b=mbcGSzo4cV4+wq7m7KuNrg3seQcU7NIDzNy9QqHVHiTWV4zTpkehljy7 GJaPWoiYSQaQIkac/Qtxy35WjrGZuBXc/8RQrRjSmlDw81/ig137hwVyJ hJ6Am5bef/kf3h1wzs992cSi17941Xur3MvvmElu4Z6JLodCbZVdpWJO8 Zjpq+LDwJTaYYTCMYLPlKl8QyHKwT8AY64ZiTy8BSnrQWnt6r9EsZS10Q q1g7HdbDbaZuG8Q4pq3X/rokMCNRSL/p+XD0BdS1GO4aSk9eNeVS92WA+ ZZ9bFKn+wew10R2ajftsdBBtrJ0Y3/eYpGt3yDt66NOTw43Yb8OPKDT86 w==; X-CSE-ConnectionGUID: wnav3QOqSLeqVPatec6WWg== X-CSE-MsgGUID: 2FUcv2OCQWSQLvQOATVvQw== X-IronPort-AV: E=McAfee;i="6600,9927,11100"; a="40249616" X-IronPort-AV: E=Sophos;i="6.08,230,1712646000"; d="scan'208,223";a="40249616" Received: from orviesa008.jf.intel.com ([10.64.159.148]) by fmvoesa101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Jun 2024 09:49:55 -0700 X-CSE-ConnectionGUID: L0C88JV3TXihXBARem94nw== X-CSE-MsgGUID: GJTOORIvQP248Oej/VAciA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.08,230,1712646000"; d="scan'208,223";a="40103295" Received: from jacob-builder.jf.intel.com ([10.54.39.125]) by orviesa008.jf.intel.com with ESMTP; 11 Jun 2024 09:49:55 -0700 From: Jacob Pan To: X86 Kernel , LKML , Thomas Gleixner , Dave Hansen , "H. Peter Anvin" , "Ingo Molnar" , "Borislav Petkov" , linux-perf-users@vger.kernel.org, Peter Zijlstra Cc: Andi Kleen , "Xin Li" Subject: Date: Tue, 11 Jun 2024 09:54:51 -0700 Message-Id: <20240611165457.156364-1-jacob.jun.pan@linux.intel.com> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit >From e52010df700cde894633c45c0b364847e63a9819 Mon Sep 17 00:00:00 2001 From: Jacob Pan Date: Tue, 11 Jun 2024 09:49:17 -0700 Subject: Subject: [PATCH v2 0/6] Add support for NMI source reporting Hi Thomas and all, Non-Maskable Interrupts (NMIs) are routed to the local Advanced Programmable Interrupt Controller (APIC) using vector #2. Before the advent of the Flexible Return and Event Delivery (FRED)[1], the vector information set by the NMI initiator was disregarded or lost within the hardware, compelling system software to poll every registered NMI handler to pinpoint the source of the NMI[2]. This approach led to several issues: 1. Inefficiency due to the CPU's time spent polling all handlers. 2. Increased latency from the additional time taken to poll all handlers. 3. The occurrence of unnecessary NMIs if they are triggered shortly after being processed by a different source. To tackle these challenges, Intel introduced NMI source reporting as a part of the FRED specification (detailed in Chapter 9). This CPU feature ensures that while all NMI sources are still aggregated into NMI vector (#2) for delivery, the source of the NMI is now conveyed through FRED event data (a 16-bit bitmap on the stack). This allows for the selective dispatch of the NMI source handler based on the bitmap, eliminating the need to invoke all NMI source handlers indiscriminately. In line with the hardware architecture, various interrupt sources can generate NMIs by encoding an NMI delivery mode. However, this patchset activates only the local NMI sources that are currently utilized by the Linux kernel, which includes: 1. Performance monitoring. 2. Inter-Processor Interrupts (IPIs) for functions like CPU backtrace, machine check, Kernel GNU Debugger (KGDB), reboot, panic stop, and self-test. Other NMI sources will continue to be handled as previously when the NMI source is not utilized or remains unidentified. Next steps: 1. KVM support 2. Optimization to reuse IDT NMI vector 2 as NMI source for "known" source. Link:https://lore.kernel.org/lkml/746fecd5-4c79-42f9-919e-912ec415e73f@zytor.com/ [1] https://www.intel.com/content/www/us/en/content-details/779982/flexible-return-and-event-delivery-fred-specification.html [2] https://lore.kernel.org/lkml/171011362209.2468526.15187874627966416701.tglx@xen13/ Thanks, Jacob --- Change logs are in individual patches. Jacob Pan (6): x86/irq: Add enumeration of NMI source reporting CPU feature x86/irq: Extend NMI handler registration interface to include source x86/irq: Factor out common NMI handling code x86/irq: Process nmi sources in NMI handler perf/x86: Enable NMI source reporting for perfmon x86/irq: Enable NMI source on IPIs delivered as NMI arch/x86/Kconfig | 9 +++ arch/x86/events/amd/ibs.c | 2 +- arch/x86/events/core.c | 11 ++- arch/x86/events/intel/core.c | 6 +- arch/x86/include/asm/apic.h | 1 + arch/x86/include/asm/cpufeatures.h | 1 + arch/x86/include/asm/disabled-features.h | 8 +- arch/x86/include/asm/irq_vectors.h | 38 +++++++++ arch/x86/include/asm/nmi.h | 4 +- arch/x86/kernel/apic/hw_nmi.c | 5 +- arch/x86/kernel/apic/ipi.c | 4 +- arch/x86/kernel/apic/local.h | 18 +++-- arch/x86/kernel/cpu/mce/inject.c | 4 +- arch/x86/kernel/cpu/mshyperv.c | 2 +- arch/x86/kernel/kgdb.c | 6 +- arch/x86/kernel/nmi.c | 99 +++++++++++++++++++++--- arch/x86/kernel/nmi_selftest.c | 7 +- arch/x86/kernel/reboot.c | 4 +- arch/x86/kernel/smp.c | 4 +- arch/x86/kernel/traps.c | 4 +- arch/x86/platform/uv/uv_nmi.c | 4 +- drivers/acpi/apei/ghes.c | 2 +- drivers/char/ipmi/ipmi_watchdog.c | 2 +- drivers/edac/igen6_edac.c | 2 +- drivers/watchdog/hpwdt.c | 6 +- 25 files changed, 200 insertions(+), 53 deletions(-) -- 2.25.1