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* x86: unify chunks of kernel/process*.cJeremy Fitzhardinge2009-03-02
| | | | | | | | | | | | | | | | | | | | With x86-32 and -64 using the same mechanism for managing the tss io permissions bitmap, large chunks of process*.c are trivially unifyable, including: - exit_thread - flush_thread - __switch_to_xtra (along with tsc enable/disable) and as bonus pickups: - sys_fork - sys_vfork (Note: asmlinkage expands to empty on x86-64) Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Merge branch 'linus' into x86/apicIngo Molnar2009-02-13
|\ | | | | | | | | | | Conflicts: arch/x86/kernel/acpi/boot.c arch/x86/mm/fault.c
| * x86: add clflush before monitor for Intel 7400 seriesPallipadi, Venkatesh2009-02-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For Intel 7400 series CPUs, the recommendation is to use a clflush on the monitored address just before monitor and mwait pair [1]. This clflush makes sure that there are no false wakeups from mwait when the monitored address was recently written to. [1] "MONITOR/MWAIT Recommendations for Intel Xeon Processor 7400 series" section in specification update document of 7400 series http://download.intel.com/design/xeon/specupdt/32033601.pdf Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86: replace CONFIG_X86_SMP with CONFIG_SMPIngo Molnar2009-01-29
|/ | | | | | | | | | | | | | | | | The x86/Voyager subarch used to have this distinction between 'x86 SMP support' and 'Voyager SMP support': config X86_SMP bool depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64) This is a pointless distinction - Voyager can (and already does) use smp_ops to implement various SMP quirks it has - and it can be extended more to cover all the specialities of Voyager. So remove this complication in the Kconfig space. Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Merge branch 'tracing-core-for-linus' of ↵Linus Torvalds2008-12-28
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (241 commits) sched, trace: update trace_sched_wakeup() tracing/ftrace: don't trace on early stage of a secondary cpu boot, v3 Revert "x86: disable X86_PTRACE_BTS" ring-buffer: prevent false positive warning ring-buffer: fix dangling commit race ftrace: enable format arguments checking x86, bts: memory accounting x86, bts: add fork and exit handling ftrace: introduce tracing_reset_online_cpus() helper tracing: fix warnings in kernel/trace/trace_sched_switch.c tracing: fix warning in kernel/trace/trace.c tracing/ring-buffer: remove unused ring_buffer size trace: fix task state printout ftrace: add not to regex on filtering functions trace: better use of stack_trace_enabled for boot up code trace: add a way to enable or disable the stack tracer x86: entry_64 - introduce FTRACE_ frame macro v2 tracing/ftrace: add the printk-msg-only option tracing/ftrace: use preempt_enable_no_resched_notrace in ring_buffer_time_stamp() x86, bts: correctly report invalid bts records ... Fixed up trivial conflict in scripts/recordmcount.pl due to SH bits being already partly merged by the SH merge.
| * Merge branch 'x86/tsc' into tracing/coreIngo Molnar2008-12-25
| |\ | | | | | | | | | | | | | | | | | | | | | Merge it to resolve this incidental conflict between the BTS fixes/cleanups and changes in x86/tsc: Conflicts: arch/x86/kernel/cpu/intel.c
| * | tracing: add "power-tracer": C/P state tracer to help power optimizationArjan van de Ven2008-11-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: new "power-tracer" ftrace plugin This patch adds a C/P-state ftrace plugin that will generate detailed statistics about the C/P-states that are being used, so that we can look at detailed decisions that the C/P-state code is making, rather than the too high level "average" that we have today. An example way of using this is: mount -t debugfs none /sys/kernel/debug echo cstate > /sys/kernel/debug/tracing/current_tracer echo 1 > /sys/kernel/debug/tracing/tracing_enabled sleep 1 echo 0 > /sys/kernel/debug/tracing/tracing_enabled cat /sys/kernel/debug/tracing/trace | perl scripts/trace/cstate.pl > out.svg Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | Merge branch 'x86/tsc' into x86/coreIngo Molnar2008-12-23
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| * | x86: support always running TSC on Intel CPUsVenki Pallipadi2008-12-16
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: reward non-stop TSCs with good TSC-based clocksources, etc. Add support for CPUID_0x80000007_Bit8 on Intel CPUs as well. This bit means that the TSC is invariant with C/P/T states and always runs at constant frequency. With Intel CPUs, we have 3 classes * CPUs where TSC runs at constant rate and does not stop n C-states * CPUs where TSC runs at constant rate, but will stop in deep C-states * CPUs where TSC rate will vary based on P/T-states and TSC will stop in deep C-states. To cover these 3, one feature bit (CONSTANT_TSC) is not enough. So, add a second bit (NONSTOP_TSC). CONSTANT_TSC indicates that the TSC runs at constant frequency irrespective of P/T-states, and NONSTOP_TSC indicates that TSC does not stop in deep C-states. CPUID_0x8000000_Bit8 indicates both these feature bit can be set. We still have CONSTANT_TSC _set_ and NONSTOP_TSC _not_set_ on some older Intel CPUs, based on model checks. We can use TSC on such CPUs for time, as long as those CPUs do not support/enter deep C-states. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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*-. \ Merge branches 'x86/apic', 'x86/cleanups', 'x86/cpufeature', ↵Ingo Molnar2008-12-23
|\ \ \ | |_|/ |/| | | | | 'x86/crashdump', 'x86/debug', 'x86/defconfig', 'x86/detect-hyper', 'x86/doc', 'x86/dumpstack', 'x86/early-printk', 'x86/fpu', 'x86/idle', 'x86/io', 'x86/memory-corruption-check', 'x86/microcode', 'x86/mm', 'x86/mtrr', 'x86/nmi-watchdog', 'x86/pat2', 'x86/pci-ioapic-boot-irq-quirks', 'x86/ptrace', 'x86/quirks', 'x86/reboot', 'x86/setup-memory', 'x86/signal', 'x86/sparse-fixes', 'x86/time', 'x86/uv' and 'x86/xen' into x86/core
| | * x86: call machine_shutdown and stop all CPUs in native_machine_haltIvan Vecera2008-11-11
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: really halt all CPUs on halt Function machine_halt (resp. native_machine_halt) is empty for x86 architectures. When command 'halt -f' is invoked, the message "System halted." is displayed but this is not really true because all CPUs are still running. There are also similar inconsistencies for other arches (some uses power-off for halt or forever-loop with IRQs enabled/disabled). IMO there should be used the same approach for all architectures OR what does the message "System halted" really mean? This patch fixes it for x86. Signed-off-by: Ivan Vecera <ivecera@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * x86: process.c declare c1e_remove_cpu before they get usedJaswinder Singh2008-12-18
|/ | | | | | | | | | | | | Impact: cleanup, avoid sparse warning Included asm/idle.h for c1e_remove_cpu() declaration. Fixes this sparse warning: CHECK arch/x86/kernel/process.c arch/x86/kernel/process.c:284:6: warning: symbol 'c1e_remove_cpu' was not declared. Should it be static? Signed-off-by: Jaswinder Singh <jaswinder@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Merge branch 'x86/unify-cpu-detect' into x86-v28-for-linus-phase4-DIngo Molnar2008-10-11
|\ | | | | | | | | | | | | Conflicts: arch/x86/kernel/cpu/common.c arch/x86/kernel/signal_64.c include/asm-x86/cpufeature.h
| * x86: remove duplicated force_mwaitYinghai Lu2008-09-08
| | | | | | | | | | Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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*-. \ Merge branches 'x86/alternatives', 'x86/cleanups', 'x86/commandline', ↵Ingo Molnar2008-10-06
|\ \ \ | | |/ | |/| | | | 'x86/crashdump', 'x86/debug', 'x86/defconfig', 'x86/doc', 'x86/exports', 'x86/fpu', 'x86/gart', 'x86/idle', 'x86/mm', 'x86/mtrr', 'x86/nmi-watchdog', 'x86/oprofile', 'x86/paravirt', 'x86/reboot', 'x86/sparse-fixes', 'x86/tsc', 'x86/urgent' and 'x86/vmalloc' into x86-v28-for-linus-phase1
| | * x86: make poll_idle behave more like the other idle methodsJoe Korty2008-08-28
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make poll_idle() behave more like the other idle methods. Currently, poll_idle() returns immediately. The other idle methods all wait indefinately for some condition to come true before returning. poll_idle should emulate these other methods and also wait for a return condition, in this case, for need_resched() to become 'true'. Without this delay the idle loop spends all of its time in the outer loop that calls poll_idle. This outer loop, these days, does real work, some of it under rcu locks. That work should only be done when idle is entered and when idle exits, not continuously while idle is spinning. Signed-off-by: Joe Korty <joe.korty@ccur.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86: c1e_idle: don't mark TSC unstable if CPU has invariant TSCAndreas Herrmann2008-09-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: Functional TSC is marked unstable on AMD family 0x10 and 0x11 CPUs. This would be wrong because for those CPUs "invariant TSC" means: "The TSC counts at the same rate in all P-states, all C states, S0, or S1" (See "Processor BIOS and Kernel Developer's Guides" for those CPUs.) [ tglx: Changed C1E to AMD C1E in the printks to avoid confusion with Intel C1E ] Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | x86: prevent C-states hang on AMD C1E enabled machinesThomas Gleixner2008-09-23
| | | | | | | | | | | | | | | | | | | | Impact: System hang when AMD C1E machines switch into C2/C3 AMD C1E enabled systems do not work with normal ACPI C-states even if the BIOS is advertising them. Limit the C-states to C1 for the ACPI processor idle code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | x86: prevent stale state of c1e_mask across CPU offline/onlineThomas Gleixner2008-09-23
|/ | | | | | | | | | | | | | | Impact: hang which happens across CPU offline/online on AMD C1E systems. When a CPU goes offline then the corresponding bit in the broadcast mask is cleared. For AMD C1E enabled CPUs we do not reenable the broadcast when the CPU comes online again as we do not clear the corresponding bit in the c1e_mask, which keeps track which CPUs have been switched to broadcast already. So on those !$@#& machines we never switch back to broadcasting after a CPU offline/online cycle. Clear the bit when the CPU plays dead. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
*-------. Merge branches 'x86/urgent', 'x86/amd-iommu', 'x86/apic', 'x86/cleanups', ↵Ingo Molnar2008-07-21
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | 'x86/core', 'x86/cpu', 'x86/fixmap', 'x86/gart', 'x86/kprobes', 'x86/memtest', 'x86/modules', 'x86/nmi', 'x86/pat', 'x86/reboot', 'x86/setup', 'x86/step', 'x86/unify-pci', 'x86/uv', 'x86/xen' and 'xen-64bit' into x86/for-linus
| | * | | | x86: consolidate the definition of the force_mwait variableThomas Petazzoni2008-07-18
| |/ / / / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The force_mwait variable iss defined either in arch/x86/kernel/cpu/amd.c or in arch/x86/kernel/setup_64.c, but it is only initialized and used in arch/x86/kernel/process.c. This patch moves the declaration to arch/x86/kernel/process.c. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Cc: michael@free-electrons.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86: reduce force_mwait visibilityJan Beulich2008-07-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It's not used anywhere outside its single referencing file. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | | | Merge branch 'linus' into x86/cleanupsIngo Molnar2008-07-18
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| * | | | x86: idle process - add checking for NULL early paramCyrill Gorcunov2008-07-09
| | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com> Cc: akpm@linux-foundation.org Cc: andi@firstfloor.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | | ACPI : Create "idle=nomwait" bootparamZhao Yakui2008-07-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | "idle=nomwait" disables the use of the MWAIT instruction from both C1 (C1_FFH) and deeper (C2C3_FFH) C-states. When MWAIT is unavailable, the BIOS and OS generally negotiate to use the HALT instruction for C1, and use IO accesses for deeper C-states. This option is useful for power and performance comparisons, and also to work around BIOS bugs where broken MWAIT support is advertised. http://bugzilla.kernel.org/show_bug.cgi?id=10807 http://bugzilla.kernel.org/show_bug.cgi?id=10914 Signed-off-by: Zhao Yakui <yakui.zhao@intel.com> Signed-off-by: Li Shaohua <shaohua.li@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com>
* | | | ACPI: Create "idle=halt" bootparamZhao Yakui2008-07-16
| |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | "idle=halt" limits the idle loop to using the halt instruction. No MWAIT, no IO accesses, no C-states deeper than C1. If something is broken in the idle code, "idle=halt" is a less severe workaround than "idle=poll" which disables all power savings. Signed-off-by: Zhao Yakui <yakui.zhao@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com>
* | | Merge branch 'generic-ipi' into generic-ipi-for-linusIngo Molnar2008-07-15
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: arch/powerpc/Kconfig arch/s390/kernel/time.c arch/x86/kernel/apic_32.c arch/x86/kernel/cpu/perfctr-watchdog.c arch/x86/kernel/i8259_64.c arch/x86/kernel/ldt.c arch/x86/kernel/nmi_64.c arch/x86/kernel/smpboot.c arch/x86/xen/smp.c include/asm-x86/hw_irq_32.h include/asm-x86/hw_irq_64.h include/asm-x86/mach-default/irq_vectors.h include/asm-x86/mach-voyager/irq_vectors.h include/asm-x86/smp.h kernel/Makefile Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | fix "smp_call_function: get rid of the unused nonatomic/retry argument"Ingo Molnar2008-06-27
| |/ | | | | | | | | | | | | | | | | fix: arch/x86/kernel/process.c: In function 'cpu_idle_wait': arch/x86/kernel/process.c:64: error: too many arguments to function 'smp_call_function' Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86: add C1E aware idle function, fixThomas Gleixner2008-07-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On Tue, 17 Jun 2008, Rafael J. Wysocki wrote: > > BTW, with the C1E patches reverted I don't get the > WARNING: at /home/rafael/src/linux-next/kernel/smp.c:215 smp_call_function_single+0x3d/0xa2 > in the log. Thomas? The BROADCAST_FORCE notification uses smp_function_call and therefor must be run with interrupts enabled. While at it, add a comment for the BROADCAST_EXIT notifier as well. Reported-and-bisected-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86, clockevents: add C1E aware idle functionThomas Gleixner2008-07-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | C1E on AMD machines is like C3 but without control from the OS. Up to now we disabled the local apic timer for those machines as it stops when the CPU goes into C1E. This excludes those machines from high resolution timers / dynamic ticks, which hurts especially X2 based laptops. The current boot time C1E detection has another, more serious flaw as well: some BIOSes do not enable C1E until the ACPI processor module is loaded. This causes systems to stop working after that point. To work nicely with C1E enabled machines we use a separate idle function, which checks on idle entry whether C1E was enabled in the Interrupt Pending Message MSR. This allows us to do timer broadcasting for C1E and covers the late enablement of C1E as well. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86: move more common idle functions/variables to process.cThomas Gleixner2008-06-10
| | | | | | | | | | | | | | more unification. Should cause no change in functionality. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86: use cpuid to check MWAIT support for C1Thomas Gleixner2008-06-10
| | | | | | | | | | | | | | | | | | | | | | cpuid(0x05) provides extended information about MWAIT in EDX when bit 0 of ECX is set. Bit 4-7 of EDX determine whether MWAIT is supported for C1. C1E enabled CPUs have these bits set to 0. Based on an earlier patch from Andi Kleen. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86: simplify idle selectionThomas Gleixner2008-06-10
|/ | | | | | | | | default_idle is selected in cpu_idle(), when no other idle routine is selected. Select it in select_idle_routine() when mwait is not selected. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: disable mwait for AMD family 10H/11H CPUsThomas Gleixner2008-05-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | The previous revert of 0c07ee38c9d4eb081758f5ad14bbffa7197e1aec left out the mwait disable condition for AMD family 10H/11H CPUs. Andreas Herrman said: It depends on the CPU. For AMD CPUs that support MWAIT this is wrong. Family 0x10 and 0x11 CPUs will enter C1 on HLT. Powersavings then depend on a clock divisor and current Pstate of the core. If all cores of a processor are in halt state (C1) the processor can enter the C1E (C1 enhanced) state. If mwait is used this will never happen. Thus HLT saves more power than MWAIT here. It might be best to switch off the mwait flag for these AMD CPU families like it was introduced with commit f039b754714a422959027cb18bb33760eb8153f0 (x86: Don't use MWAIT on AMD Family 10) Re-add the AMD families 10H/11H check and disable the mwait usage for those. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: remove mwait capability C-state checkIngo Molnar2008-05-17
| | | | | | | | | | | | | | | | | | | | | | | | Vegard Nossum reports: | powertop shows between 200-400 wakeups/second with the description | "<kernel IPI>: Rescheduling interrupts" when all processors have load (e.g. | I need to run two busy-loops on my 2-CPU system for this to show up). | | The bisect resulted in this commit: | | commit 0c07ee38c9d4eb081758f5ad14bbffa7197e1aec | Date: Wed Jan 30 13:33:16 2008 +0100 | | x86: use the correct cpuid method to detect MWAIT support for C states remove the functional effects of this patch and make mwait unconditional. A future patch will turn off mwait on specific CPUs where that causes power to be wasted. Bisected-by: Vegard Nossum <vegard.nossum@gmail.com> Tested-by: Vegard Nossum <vegard.nossum@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* fix idle (arch, acpi and apm) and lockdepPeter Zijlstra2008-04-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | OK, so 25-mm1 gave a lockdep error which made me look into this. The first thing that I noticed was the horrible mess; the second thing I saw was hacks like: 71e93d15612c61c2e26a169567becf088e71b8ff The problem is that arch idle routines are somewhat inconsitent with their IRQ state handling and instead of fixing _that_, we go paper over the problem. So the thing I've tried to do is set a standard for idle routines and fix them all up to adhere to that. So the rules are: idle routines are entered with IRQs disabled idle routines will exit with IRQs enabled Nearly all already did this in one form or another. Merge the 32 and 64 bit bits so they no longer have different bugs. As for the actual lockdep warning; __sti_mwait() did a plainly un-annotated irq-enable. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Tested-by: Bob Copeland <me@bobcopeland.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: fpu xstate split cleanupSuresh Siddha2008-04-19
| | | | | Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86, fpu: lazy allocation of FPU area - v5Suresh Siddha2008-04-19
| | | | | | | | | | | | | Only allocate the FPU area when the application actually uses FPU, i.e., in the first lazy FPU trap. This could save memory for non-fpu using apps. for example: on my system after boot, there are around 300 processes, with only 17 using FPU. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86, fpu: split FPU state from task struct - v5Suresh Siddha2008-04-19
Split the FPU save area from the task struct. This allows easy migration of FPU context, and it's generally cleaner. It also allows the following two optimizations: 1) only allocate when the application actually uses FPU, so in the first lazy FPU trap. This could save memory for non-fpu using apps. Next patch does this lazy allocation. 2) allocate the right size for the actual cpu rather than 512 bytes always. Patches enabling xsave/xrstor support (coming shortly) will take advantage of this. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>