From 40e2d7f9b5dae048789c64672bf3027fbb663ffa Mon Sep 17 00:00:00 2001 From: Len Brown Date: Wed, 18 Dec 2013 16:44:57 -0500 Subject: x86 idle: Repair large-server 50-watt idle-power regression Linux 3.10 changed the timing of how thread_info->flags is touched: x86: Use generic idle loop (7d1a941731fabf27e5fb6edbebb79fe856edb4e5) This caused Intel NHM-EX and WSM-EX servers to experience a large number of immediate MONITOR/MWAIT break wakeups, which caused cpuidle to demote from deep C-states to shallow C-states, which caused these platforms to experience a significant increase in idle power. Note that this issue was already present before the commit above, however, it wasn't seen often enough to be noticed in power measurements. Here we extend an errata workaround from the Core2 EX "Dunnington" to extend to NHM-EX and WSM-EX, to prevent these immediate returns from MWAIT, reducing idle power on these platforms. While only acpi_idle ran on Dunnington, intel_idle may also run on these two newer systems. As of today, there are no other models that are known to need this tweak. Link: http://lkml.kernel.org/r/CAJvTdK=%2BaNN66mYpCGgbHGCHhYQAKx-vB0kJSWjVpsNb_hOAtQ@mail.gmail.com Signed-off-by: Len Brown Link: http://lkml.kernel.org/r/baff264285f6e585df757d58b17788feabc68918.1387403066.git.len.brown@intel.com Cc: # 3.12.x, 3.11.x, 3.10.x Signed-off-by: H. Peter Anvin --- arch/x86/kernel/cpu/intel.c | 3 ++- drivers/idle/intel_idle.c | 3 +++ 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index dc1ec0dff939..ea04b342c026 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -387,7 +387,8 @@ static void init_intel(struct cpuinfo_x86 *c) set_cpu_cap(c, X86_FEATURE_PEBS); } - if (c->x86 == 6 && c->x86_model == 29 && cpu_has_clflush) + if (c->x86 == 6 && cpu_has_clflush && + (c->x86_model == 29 || c->x86_model == 46 || c->x86_model == 47)) set_cpu_cap(c, X86_FEATURE_CLFLUSH_MONITOR); #ifdef CONFIG_X86_64 diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index 92d1206482a6..f80b700f821c 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -377,6 +377,9 @@ static int intel_idle(struct cpuidle_device *dev, if (!current_set_polling_and_test()) { + if (this_cpu_has(X86_FEATURE_CLFLUSH_MONITOR)) + clflush((void *)¤t_thread_info()->flags); + __monitor((void *)¤t_thread_info()->flags, 0, 0); smp_mb(); if (!need_resched()) -- cgit v1.2.2 From fce7d3bfc0ae70ca2a57868f2a9708b13185fd1f Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Mon, 16 Dec 2013 14:39:40 +0000 Subject: x86/efi: Don't select EFI from certain special ACPI drivers Commit 7ea6c6c1 ("Move cper.c from drivers/acpi/apei to drivers/firmware/efi") results in CONFIG_EFI being enabled even when the user doesn't want this. Since ACPI APEI used to build fine without UEFI (and as far as I know also has no functional depency on it), at least in that case using a reverse dependency is wrong (and a straight one isn't needed). Whether the same is true for ACPI_EXTLOG I don't know - if there is a functional dependency, it should depend on EFI rather than selecting it. It certainly has (currently) no build dependency. Adjust Kconfig and build logic so that the bad dependency gets avoided. Signed-off-by: Jan Beulich Acked-by: Tony Luck Cc: Matt Fleming Link: http://lkml.kernel.org/r/52AF1EBC020000780010DBF9@nat28.tlf.novell.com Signed-off-by: Ingo Molnar --- drivers/acpi/Kconfig | 1 - drivers/acpi/apei/Kconfig | 1 - drivers/firmware/Makefile | 1 + drivers/firmware/efi/Kconfig | 6 +++--- drivers/firmware/efi/Makefile | 2 +- 5 files changed, 5 insertions(+), 6 deletions(-) diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 5d9248526d78..4770de5707b9 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -348,7 +348,6 @@ source "drivers/acpi/apei/Kconfig" config ACPI_EXTLOG tristate "Extended Error Log support" depends on X86_MCE && X86_LOCAL_APIC - select EFI select UEFI_CPER default n help diff --git a/drivers/acpi/apei/Kconfig b/drivers/acpi/apei/Kconfig index 786294bb682c..3650b2183227 100644 --- a/drivers/acpi/apei/Kconfig +++ b/drivers/acpi/apei/Kconfig @@ -2,7 +2,6 @@ config ACPI_APEI bool "ACPI Platform Error Interface (APEI)" select MISC_FILESYSTEMS select PSTORE - select EFI select UEFI_CPER depends on X86 help diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile index 299fad6b5867..5373dc5b6011 100644 --- a/drivers/firmware/Makefile +++ b/drivers/firmware/Makefile @@ -14,3 +14,4 @@ obj-$(CONFIG_FIRMWARE_MEMMAP) += memmap.o obj-$(CONFIG_GOOGLE_FIRMWARE) += google/ obj-$(CONFIG_EFI) += efi/ +obj-$(CONFIG_UEFI_CPER) += efi/ diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig index 3150aa4874e8..6aecbc86ec94 100644 --- a/drivers/firmware/efi/Kconfig +++ b/drivers/firmware/efi/Kconfig @@ -36,7 +36,7 @@ config EFI_VARS_PSTORE_DEFAULT_DISABLE backend for pstore by default. This setting can be overridden using the efivars module's pstore_disable parameter. -config UEFI_CPER - def_bool n - endmenu + +config UEFI_CPER + bool diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile index 9ba156d3c775..6c2a41ec21ba 100644 --- a/drivers/firmware/efi/Makefile +++ b/drivers/firmware/efi/Makefile @@ -1,7 +1,7 @@ # # Makefile for linux kernel # -obj-y += efi.o vars.o +obj-$(CONFIG_EFI) += efi.o vars.o obj-$(CONFIG_EFI_VARS) += efivars.o obj-$(CONFIG_EFI_VARS_PSTORE) += efi-pstore.o obj-$(CONFIG_UEFI_CPER) += cper.o -- cgit v1.2.2