/****************************************************************************** * acpi.h * acpi file for domain 0 kernel * * Copyright (c) 2011 Konrad Rzeszutek Wilk * Copyright (c) 2011 Yu Ke * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License version 2 * as published by the Free Software Foundation; or, when distributed * separately from the Linux kernel or incorporated into other * software packages, subject to the following license: * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this source file (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, * and to permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS * IN THE SOFTWARE. */ #ifndef _XEN_ACPI_H #define _XEN_ACPI_H #include #ifdef CONFIG_XEN_DOM0 #include #include #include #define ACPI_MEMORY_DEVICE_CLASS "memory" #define ACPI_MEMORY_DEVICE_HID "PNP0C80" #define ACPI_MEMORY_DEVICE_NAME "Hotplug Mem Device" int xen_stub_memory_device_init(void); void xen_stub_memory_device_exit(void); #define ACPI_PROCESSOR_CLASS "processor" #define ACPI_PROCESSOR_DEVICE_HID "ACPI0007" #define ACPI_PROCESSOR_DEVICE_NAME "Processor" int xen_stub_processor_init(void); void xen_stub_processor_exit(void); void xen_pcpu_hotplug_sync(void); int xen_pcpu_id(uint32_t acpi_id); static inline int xen_acpi_get_pxm(acpi_handle h) { unsigned long long pxm; acpi_status status; acpi_handle handle; acpi_handle phandle = h; do { handle = phandle; status = acpi_evaluate_integer(handle, "_PXM", NULL, &pxm); if (ACPI_SUCCESS(status)) return pxm; status = acpi_get_parent(handle, &phandle); } while (ACPI_SUCCESS(status)); return -ENXIO; } int xen_acpi_notify_hypervisor_sleep(u8 sleep_state, u32 pm1a_cnt, u32 pm1b_cnd); int xen_acpi_notify_hypervisor_extended_sleep(u8 sleep_state, u32 val_a, u32 val_b); static inline int xen_acpi_suspend_lowlevel(void) { /* * Xen will save and restore CPU context, so * we can skip that and just go straight to * the suspend. */ acpi_enter_sleep_state(ACPI_STATE_S3); return 0; } static inline void xen_acpi_sleep_register(void) { if (xen_initial_domain()) { acpi_os_set_prepare_sleep( &xen_acpi_notify_hypervisor_sleep); acpi_os_set_prepare_extended_sleep( &xen_acpi_notify_hypervisor_extended_sleep); acpi_suspend_lowlevel = xen_acpi_suspend_lowlevel; } } #else static inline void xen_acpi_sleep_register(void) { } #endif #endif /* _XEN_ACPI_H */ b22efa1db9f6e71b24440b5f1d93e968ee3'>bench/futex-lock-pi.c
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authorSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>2017-02-03 14:18:39 -0800
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2017-02-04 00:11:08 +0100
commit6e978b22efa1db9f6e71b24440b5f1d93e968ee3 (patch)
treec666f7a26b860674848949e39a610222b0723f89 /tools/perf/bench/futex-lock-pi.c
parent3c223c19aea85d3dda1416c187915f4a30b04b1f (diff)
cpufreq: intel_pstate: Disable energy efficiency optimization
Some Kabylake desktop processors may not reach max turbo when running in HWP mode, even if running under sustained 100% utilization. This occurs when the HWP.EPP (Energy Performance Preference) is set to "balance_power" (0x80) -- the default on most systems. It occurs because the platform BIOS may erroneously enable an energy-efficiency setting -- MSR_IA32_POWER_CTL BIT-EE, which is not recommended to be enabled on this SKU. On the failing systems, this BIOS issue was not discovered when the desktop motherboard was tested with Windows, because the BIOS also neglects to provide the ACPI/CPPC table, that Windows requires to enable HWP, and so Windows runs in legacy P-state mode, where this setting has no effect. Linux' intel_pstate driver does not require ACPI/CPPC to enable HWP, and so it runs in HWP mode, exposing this incorrect BIOS configuration. There are several ways to address this problem. First, Linux can also run in legacy P-state mode on this system. As intel_pstate is how Linux enables HWP, booting with "intel_pstate=disable" will run in acpi-cpufreq/ondemand legacy p-state mode. Or second, the "performance" governor can be used with intel_pstate, which will modify HWP.EPP to 0. Or third, starting in 4.10, the /sys/devices/system/cpu/cpufreq/policy*/energy_performance_preference attribute in can be updated from "balance_power" to "performance". Or fourth, apply this patch, which fixes the erroneous setting of MSR_IA32_POWER_CTL BIT_EE on this model, allowing the default configuration to function as designed. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Reviewed-by: Len Brown <len.brown@intel.com> Cc: 4.6+ <stable@vger.kernel.org> # 4.6+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'tools/perf/bench/futex-lock-pi.c')