Commit Graph

244 Commits

Author SHA1 Message Date
Rik van Riel
c474e50711 x86/fpu: Split old_fpu & new_fpu handling into separate functions
By moving all of the new_fpu state handling into switch_fpu_finish(),
the code can be simplified some more.

This gets rid of the prefetch, but given the size of the FPU register
state on modern CPUs, and the amount of work done by __switch_to()
inbetween both functions, the value of a single cache line prefetch
seems somewhat dubious anyway.

Signed-off-by: Rik van Riel <riel@redhat.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1476447331-21566-3-git-send-email-riel@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-16 11:38:41 +02:00
Andy Lutomirski
1ef55be16e x86/asm: Get rid of __read_cr4_safe()
We use __read_cr4() vs __read_cr4_safe() inconsistently.  On
CR4-less CPUs, all CR4 bits are effectively clear, so we can make
the code simpler and more robust by making __read_cr4() always fix
up faults on 32-bit kernels.

This may fix some bugs on old 486-like CPUs, but I don't have any
easy way to test that.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: david@saggiorato.net
Link: http://lkml.kernel.org/r/ea647033d357d9ce2ad2bbde5a631045f5052fb6.1475178370.git.luto@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-30 12:40:12 +02:00
Brian Gerst
ffcb043ba5 sched/x86: Fix thread_saved_pc()
thread_saved_pc() was using a completely bogus method to get the return
address.  Since switch_to() was previously inlined, there was no sane way
to know where on the stack the return address was stored.  Now with the
frame of a sleeping thread well defined, this can be implemented correctly.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1471106302-10159-7-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-24 12:31:51 +02:00
Brian Gerst
616d24835e sched/x86: Pass kernel thread parameters in 'struct fork_frame'
Instead of setting up a fake pt_regs context, put the kernel thread
function pointer and arg into the unused callee-restored registers
of 'struct fork_frame'.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1471106302-10159-6-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-24 12:31:50 +02:00
Brian Gerst
0100301bfd sched/x86: Rewrite the switch_to() code
Move the low-level context switch code to an out-of-line asm stub instead of
using complex inline asm.  This allows constructing a new stack frame for the
child process to make it seamlessly flow to ret_from_fork without an extra
test and branch in __switch_to().  It also improves code generation for
__schedule() by using the C calling convention instead of clobbering all
registers.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1471106302-10159-5-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-24 12:31:41 +02:00
Paul Gortmaker
186f43608a x86/kernel: Audit and remove any unnecessary uses of module.h
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance
for the presence of either and replace as needed.  Build testing
revealed some implicit header usage that was fixed up accordingly.

Note that some bool/obj-y instances remain since module.h is
the header for some exception table entry stuff, and for things
like __init_or_module (code that is tossed when MODULES=n).

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160714001901.31603-4-paul.gortmaker@windriver.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-14 15:06:41 +02:00
Peter Zijlstra
d87b7a3379 sched/core, sched/x86: Kill thread_info::saved_preempt_count
With the introduction of the context switch preempt_count invariant,
and the demise of PREEMPT_ACTIVE, its pointless to save/restore the
per-cpu preemption count, it must always be 2.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-06 17:08:18 +02:00
Thomas Gleixner
7ba78053aa x86/process: Unify 32bit and 64bit implementations of get_wchan()
The stack layout and the functionality is identical. Use the 64bit
version for all of x86.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: kasan-dev <kasan-dev@googlegroups.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Wolfram Gloger <wmglo@dent.med.uni-muenchen.de>
Link: http://lkml.kernel.org/r/20150930083302.779694618@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-09-30 21:51:34 +02:00
Brian Gerst
ba3e127ec1 x86/vm86: Clean up vm86.h includes
vm86.h was being implicitly included in alot of places via
processor.h, which in turn got it from math_emu.h.  Break that
chain and explicitly include vm86.h in all files that need it.
Also remove unused vm86 field from math_emu_info.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1438148483-11932-7-git-send-email-brgerst@gmail.com
[ Fixed build failure. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-31 13:31:10 +02:00
Josh Triplett
c1bd55f922 x86: opt into HAVE_COPY_THREAD_TLS, for both 32-bit and 64-bit
For 32-bit userspace on a 64-bit kernel, this requires modifying
stub32_clone to actually swap the appropriate arguments to match
CONFIG_CLONE_BACKWARDS, rather than just leaving the C argument for tls
broken.

Patch co-authored by Josh Triplett and Thiago Macieira.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thiago Macieira <thiago.macieira@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30 19:45:01 -07:00
Linus Torvalds
d70b3ef54c Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 core updates from Ingo Molnar:
 "There were so many changes in the x86/asm, x86/apic and x86/mm topics
  in this cycle that the topical separation of -tip broke down somewhat -
  so the result is a more traditional architecture pull request,
  collected into the 'x86/core' topic.

  The topics were still maintained separately as far as possible, so
  bisectability and conceptual separation should still be pretty good -
  but there were a handful of merge points to avoid excessive
  dependencies (and conflicts) that would have been poorly tested in the
  end.

  The next cycle will hopefully be much more quiet (or at least will
  have fewer dependencies).

  The main changes in this cycle were:

   * x86/apic changes, with related IRQ core changes: (Jiang Liu, Thomas
     Gleixner)

     - This is the second and most intrusive part of changes to the x86
       interrupt handling - full conversion to hierarchical interrupt
       domains:

          [IOAPIC domain]   -----
                                 |
          [MSI domain]      --------[Remapping domain] ----- [ Vector domain ]
                                 |   (optional)          |
          [HPET MSI domain] -----                        |
                                                         |
          [DMAR domain]     -----------------------------
                                                         |
          [Legacy domain]   -----------------------------

       This now reflects the actual hardware and allowed us to distangle
       the domain specific code from the underlying parent domain, which
       can be optional in the case of interrupt remapping.  It's a clear
       separation of functionality and removes quite some duct tape
       constructs which plugged the remap code between ioapic/msi/hpet
       and the vector management.

     - Intel IOMMU IRQ remapping enhancements, to allow direct interrupt
       injection into guests (Feng Wu)

   * x86/asm changes:

     - Tons of cleanups and small speedups, micro-optimizations.  This
       is in preparation to move a good chunk of the low level entry
       code from assembly to C code (Denys Vlasenko, Andy Lutomirski,
       Brian Gerst)

     - Moved all system entry related code to a new home under
       arch/x86/entry/ (Ingo Molnar)

     - Removal of the fragile and ugly CFI dwarf debuginfo annotations.
       Conversion to C will reintroduce many of them - but meanwhile
       they are only getting in the way, and the upstream kernel does
       not rely on them (Ingo Molnar)

     - NOP handling refinements. (Borislav Petkov)

   * x86/mm changes:

     - Big PAT and MTRR rework: making the code more robust and
       preparing to phase out exposing direct MTRR interfaces to drivers -
       in favor of using PAT driven interfaces (Toshi Kani, Luis R
       Rodriguez, Borislav Petkov)

     - New ioremap_wt()/set_memory_wt() interfaces to support
       Write-Through cached memory mappings.  This is especially
       important for good performance on NVDIMM hardware (Toshi Kani)

   * x86/ras changes:

     - Add support for deferred errors on AMD (Aravind Gopalakrishnan)

       This is an important RAS feature which adds hardware support for
       poisoned data.  That means roughly that the hardware marks data
       which it has detected as corrupted but wasn't able to correct, as
       poisoned data and raises an APIC interrupt to signal that in the
       form of a deferred error.  It is the OS's responsibility then to
       take proper recovery action and thus prolonge system lifetime as
       far as possible.

     - Add support for Intel "Local MCE"s: upcoming CPUs will support
       CPU-local MCE interrupts, as opposed to the traditional system-
       wide broadcasted MCE interrupts (Ashok Raj)

     - Misc cleanups (Borislav Petkov)

   * x86/platform changes:

     - Intel Atom SoC updates

  ... and lots of other cleanups, fixlets and other changes - see the
  shortlog and the Git log for details"

* 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (222 commits)
  x86/hpet: Use proper hpet device number for MSI allocation
  x86/hpet: Check for irq==0 when allocating hpet MSI interrupts
  x86/mm/pat, drivers/infiniband/ipath: Use arch_phys_wc_add() and require PAT disabled
  x86/mm/pat, drivers/media/ivtv: Use arch_phys_wc_add() and require PAT disabled
  x86/platform/intel/baytrail: Add comments about why we disabled HPET on Baytrail
  genirq: Prevent crash in irq_move_irq()
  genirq: Enhance irq_data_to_desc() to support hierarchy irqdomain
  iommu, x86: Properly handle posted interrupts for IOMMU hotplug
  iommu, x86: Provide irq_remapping_cap() interface
  iommu, x86: Setup Posted-Interrupts capability for Intel iommu
  iommu, x86: Add cap_pi_support() to detect VT-d PI capability
  iommu, x86: Avoid migrating VT-d posted interrupts
  iommu, x86: Save the mode (posted or remapped) of an IRTE
  iommu, x86: Implement irq_set_vcpu_affinity for intel_ir_chip
  iommu: dmar: Provide helper to copy shared irte fields
  iommu: dmar: Extend struct irte for VT-d Posted-Interrupts
  iommu: Add new member capability to struct irq_remap_ops
  x86/asm/entry/64: Disentangle error_entry/exit gsbase/ebx/usermode code
  x86/asm/entry/32: Shorten __audit_syscall_entry() args preparation
  x86/asm/entry/32: Explain reloading of registers after __audit_syscall_entry()
  ...
2015-06-22 17:59:09 -07:00
Ingo Molnar
78f7f1e54b x86/fpu: Rename fpu-internal.h to fpu/internal.h
This unifies all the FPU related header files under a unified, hiearchical
naming scheme:

 - asm/fpu/types.h:      FPU related data types, needed for 'struct task_struct',
                         widely included in almost all kernel code, and hence kept
                         as small as possible.

 - asm/fpu/api.h:        FPU related 'public' methods exported to other subsystems.

 - asm/fpu/internal.h:   FPU subsystem internal methods

 - asm/fpu/xsave.h:      XSAVE support internal methods

(Also standardize the header guard in asm/fpu/internal.h.)

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:31 +02:00
Ingo Molnar
384a23f939 x86/fpu: Use 'struct fpu' in switch_fpu_finish()
Migrate this function to pure 'struct fpu' usage.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:27 +02:00
Ingo Molnar
cb8818b6ac x86/fpu: Use 'struct fpu' in switch_fpu_prepare()
Migrate this function to pure 'struct fpu' usage.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:27 +02:00
Ingo Molnar
3a0aee4801 x86/fpu: Rename math_state_restore() to fpu__restore()
Move to the new fpu__*() namespace.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:18 +02:00
Ingo Molnar
f89e32e0a3 x86/fpu: Fix header file dependencies of fpu-internal.h
Fix a minor header file dependency bug in asm/fpu-internal.h: it
relies on i387.h but does not include it. All users of fpu-internal.h
included it explicitly.

Also remove unnecessary includes, to reduce compilation time.

This also makes it easier to use it as a standalone header file
for FPU internals, such as an upcoming C module in arch/x86/kernel/fpu/.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:47:16 +02:00
Denys Vlasenko
fed7c3f0f7 x86/entry: Remove unused 'kernel_stack' per-cpu variable
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1429889495-27850-2-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 13:49:43 +02:00
Denys Vlasenko
ef593260f0 x86/asm/entry: Get rid of KERNEL_STACK_OFFSET
PER_CPU_VAR(kernel_stack) was set up in a way where it points
five stack slots below the top of stack.

Presumably, it was done to avoid one "sub $5*8,%rsp"
in syscall/sysenter code paths, where iret frame needs to be
created by hand.

Ironically, none of them benefits from this optimization,
since all of them need to allocate additional data on stack
(struct pt_regs), so they still have to perform subtraction.

This patch eliminates KERNEL_STACK_OFFSET.

PER_CPU_VAR(kernel_stack) now points directly to top of stack.
pt_regs allocations are adjusted to allocate iret frame as well.
Hopefully we can merge it later with 32-bit specific
PER_CPU_VAR(cpu_current_top_of_stack) variable...

Net result in generated code is that constants in several insns
are changed.

This change is necessary for changing struct pt_regs creation
in SYSCALL64 code path from MOV to PUSH instructions.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1426785469-15125-2-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-24 19:42:38 +01:00
Andy Lutomirski
f39b6f0ef8 x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()'
user_mode_vm() and user_mode() are now the same.  Change all callers
of user_mode_vm() to user_mode().

The next patch will remove the definition of user_mode_vm.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brad Spengler <spender@grsecurity.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/43b1f57f3df70df5a08b0925897c660725015554.1426728647.git.luto@kernel.org
[ Merged to a more recent kernel. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-23 11:14:17 +01:00
Brian Gerst
1daeaa3151 x86/asm/entry: Fix execve() and sigreturn() syscalls to always return via IRET
Both the execve() and sigreturn() family of syscalls have the
ability to change registers in ways that may not be compatabile
with the syscall path they were called from.

In particular, SYSRET and SYSEXIT can't handle non-default %cs and %ss,
and some bits in eflags.

These syscalls have stubs that are hardcoded to jump to the IRET path,
and not return to the original syscall path.

The following commit:

   76f5df43ca ("Always allocate a complete "struct pt_regs" on the kernel stack")

recently changed this for some 32-bit compat syscalls, but introduced a bug where
execve from a 32-bit program to a 64-bit program would fail because it still returned
via SYSRETL. This caused Wine to fail when built for both 32-bit and 64-bit.

This patch sets TIF_NOTIFY_RESUME for execve() and sigreturn() so
that the IRET path is always taken on exit to userspace.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1426978461-32089-1-git-send-email-brgerst@gmail.com
[ Improved the changelog and comments. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-23 08:52:46 +01:00
Andy Lutomirski
a7fcf28d43 x86/asm/entry: Replace this_cpu_sp0() with current_top_of_stack() and fix it on x86_32
I broke 32-bit kernels.  The implementation of sp0 was correct
as far as I can tell, but sp0 was much weirder on x86_32 than I
realized.  It has the following issues:

 - Init's sp0 is inconsistent with everything else's: non-init tasks
   are offset by 8 bytes.  (I have no idea why, and the comment is unhelpful.)

 - vm86 does crazy things to sp0.

Fix it up by replacing this_cpu_sp0() with
current_top_of_stack() and using a new percpu variable to track
the top of the stack on x86_32.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 75182b1632 ("x86/asm/entry: Switch all C consumers of kernel_stack to this_cpu_sp0()")
Link: http://lkml.kernel.org/r/d09dbe270883433776e0cbee3c7079433349e96d.1425692936.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-07 09:34:03 +01:00
Andy Lutomirski
b27559a433 x86/asm/entry: Delay loading sp0 slightly on task switch
The change:

  75182b1632 ("x86/asm/entry: Switch all C consumers of kernel_stack to this_cpu_sp0()")

had the unintended side effect of changing the return value of
current_thread_info() during part of the context switch process.
Change it back.

This has no effect as far as I can tell -- it's just for
consistency.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/9fcaa47dd8487db59eed7a3911b6ae409476763e.1425692936.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-07 09:34:03 +01:00
Andy Lutomirski
24933b82c0 x86/asm/entry: Rename 'init_tss' to 'cpu_tss'
It has nothing to do with init -- there's only one TSS per cpu.

Other names considered include:

 - current_tss: Confusing because we never switch the tss.
 - singleton_tss: Too long.

This patch was generated with 's/init_tss/cpu_tss/g'.  Followup
patches will fix INIT_TSS and INIT_TSS_IST by hand.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/da29fb2a793e4f649d93ce2d1ed320ebe8516262.1425611534.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-06 08:32:58 +01:00
Andy Lutomirski
1e02ce4ccc x86: Store a per-cpu shadow copy of CR4
Context switches and TLB flushes can change individual bits of CR4.
CR4 reads take several cycles, so store a shadow copy of CR4 in a
per-cpu variable.

To avoid wasting a cache line, I added the CR4 shadow to
cpu_tlbstate, which is already touched in switch_mm.  The heaviest
users of the cr4 shadow will be switch_mm and __switch_to_xtra, and
__switch_to_xtra is called shortly after switch_mm during context
switch, so the cacheline is likely to be hot.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/3a54dd3353fffbf84804398e00dfdc5b7c1afd7d.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 12:10:42 +01:00
Oleg Nesterov
6f46b3aef0 x86: copy_thread: Don't nullify ->ptrace_bps twice
Both 32bit and 64bit versions of copy_thread() do memset(ptrace_bps)
twice for no reason, kill the 2nd memset().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20140902175733.GA21676@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-09-02 14:51:17 -07:00
Oleg Nesterov
dc56c0f9b8 x86, fpu: Shift "fpu_counter = 0" from copy_thread() to arch_dup_task_struct()
Cosmetic, but I think thread.fpu_counter should be initialized in
arch_dup_task_struct() too, along with other "fpu" variables. And
probably it make sense to turn it into thread.fpu->counter.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20140902175730.GA21669@redhat.com
Reviewed-by: Suresh Siddha <sbsiddha@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-09-02 14:51:16 -07:00
Steven Rostedt
198d208df4 x86: Keep thread_info on thread stack in x86_32
x86_64 uses a per_cpu variable kernel_stack to always point to
the thread stack of current. This is where the thread_info is stored
and is accessed from this location even when the irq or exception stack
is in use. This removes the complexity of having to maintain the
thread info on the stack when interrupts are running and having to
copy the preempt_count and other fields to the interrupt stack.

x86_32 uses the old method of copying the thread_info from the thread
stack to the exception stack just before executing the exception.

Having the two different requires #ifdefs and also the x86_32 way
is a bit of a pain to maintain. By converting x86_32 to the same
method of x86_64, we can remove #ifdefs, clean up the x86_32 code
a little, and remove the overhead of the copy.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20110806012354.263834829@goodmis.org
Link: http://lkml.kernel.org/r/20140206144321.852942014@goodmis.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-06 16:56:55 -08:00
Paul Gortmaker
663b55b9b3 x86: Delete non-required instances of include <linux/init.h>
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>.  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

[ hpa: undid incorrect removal from arch/x86/kernel/head_32.S ]

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Link: http://lkml.kernel.org/r/1389054026-12947-1-git-send-email-paul.gortmaker@windriver.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-01-06 21:25:18 -08:00
Vineet Gupta
c375f15a43 x86: move fpu_counter into ARCH specific thread_struct
Only a couple of arches (sh/x86) use fpu_counter in task_struct so it can
be moved out into ARCH specific thread_struct, reducing the size of
task_struct for other arches.

Compile tested i386_defconfig + gcc 4.7.3

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Paul Mundt <paul.mundt@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:13 +09:00
Peter Zijlstra
c2daa3bed5 sched, x86: Provide a per-cpu preempt_count implementation
Convert x86 to use a per-cpu preemption count. The reason for doing so
is that accessing per-cpu variables is a lot cheaper than accessing
thread_info variables.

We still need to save/restore the actual preemption count due to
PREEMPT_ACTIVE so we place the per-cpu __preempt_count variable in the
same cache-line as the other hot __switch_to() variables such as
current_task.

NOTE: this save/restore is required even for !PREEMPT kernels as
cond_resched() also relies on preempt_count's PREEMPT_ACTIVE to ignore
task_struct::state.

Also rename thread_info::preempt_count to ensure nobody is
'accidentally' still poking at it.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-gzn5rfsf8trgjoqx8hyayy3q@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-25 14:07:57 +02:00
Andi Kleen
35ea7903b8 x86, asmlinkage: Make 32bit/64bit __switch_to visible
This function is called from inline assembler, so has to be visible.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1375740170-7446-6-git-send-email-andi@firstfloor.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-08-06 14:18:30 -07:00
Linus Torvalds
55a0d3ff60 Merge branch 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 debug update from Ingo Molnar:
 "Misc debuggability improvements:

   - Optimize the x86 CPU register printout a bit
   - Expose the tboot TXT log via debugfs
   - Small do_debug() cleanup"

* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/tboot: Provide debugfs interfaces to access TXT log
  x86: Remove weird PTR_ERR() in do_debug
  x86/debug: Only print out DR registers if they are not power-on defaults
2013-07-02 16:25:06 -07:00
H. Peter Anvin
1adfa76a95 x86, flags: Rename X86_EFLAGS_BIT1 to X86_EFLAGS_FIXED
Bit 1 in the x86 EFLAGS is always set.  Name the macro something that
actually tries to explain what it is all about, rather than being a
tautology.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Link: http://lkml.kernel.org/n/tip-f10rx5vjjm6tfnt8o1wseb3v@git.kernel.org
2013-06-25 16:25:32 -07:00
Dave Jones
4338774cd4 x86/debug: Only print out DR registers if they are not power-on defaults
The DR registers are rarely useful when decoding oopses.
With screen real estate during oopses at a premium, we can save
two lines by only printing out these registers when they are set
to something other than they power-on state.

Signed-off-by: Dave Jones <davej@redhat.com>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20130618160911.GA24487@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-19 14:33:59 +02:00
Tejun Heo
a43cb95d54 dump_stack: unify debug information printed by show_regs()
show_regs() is inherently arch-dependent but it does make sense to print
generic debug information and some archs already do albeit in slightly
different forms.  This patch introduces a generic function to print debug
information from show_regs() so that different archs print out the same
information and it's much easier to modify what's printed.

show_regs_print_info() prints out the same debug info as dump_stack()
does plus task and thread_info pointers.

* Archs which didn't print debug info now do.

  alpha, arc, blackfin, c6x, cris, frv, h8300, hexagon, ia64, m32r,
  metag, microblaze, mn10300, openrisc, parisc, score, sh64, sparc,
  um, xtensa

* Already prints debug info.  Replaced with show_regs_print_info().
  The printed information is superset of what used to be there.

  arm, arm64, avr32, mips, powerpc, sh32, tile, unicore32, x86

* s390 is special in that it used to print arch-specific information
  along with generic debug info.  Heiko and Martin think that the
  arch-specific extra isn't worth keeping s390 specfic implementation.
  Converted to use the generic version.

Note that now all archs print the debug info before actual register
dumps.

An example BUG() dump follows.

 kernel BUG at /work/os/work/kernel/workqueue.c:4841!
 invalid opcode: 0000 [] PREEMPT SMP DEBUG_PAGEALLOC
 Modules linked in:
 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ 
 Hardware name: empty empty/S3992, BIOS 080011  10/26/2007
 task: ffff88007c85e040 ti: ffff88007c860000 task.ti: ffff88007c860000
 RIP: 0010:[<ffffffff8234a07e>]  [<ffffffff8234a07e>] init_workqueues+0x4/0x6
 RSP: 0000:ffff88007c861ec8  EFLAGS: 00010246
 RAX: ffff88007c861fd8 RBX: ffffffff824466a8 RCX: 0000000000000001
 RDX: 0000000000000046 RSI: 0000000000000001 RDI: ffffffff8234a07a
 RBP: ffff88007c861ec8 R08: 0000000000000000 R09: 0000000000000000
 R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8234a07a
 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 FS:  0000000000000000(0000) GS:ffff88007dc00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
 CR2: ffff88015f7ff000 CR3: 00000000021f1000 CR4: 00000000000007f0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
 Stack:
  ffff88007c861ef8 ffffffff81000312 ffffffff824466a8 ffff88007c85e650
  0000000000000003 0000000000000000 ffff88007c861f38 ffffffff82335e5d
  ffff88007c862080 ffffffff8223d8c0 ffff88007c862080 ffffffff81c47760
 Call Trace:
  [<ffffffff81000312>] do_one_initcall+0x122/0x170
  [<ffffffff82335e5d>] kernel_init_freeable+0x9b/0x1c8
  [<ffffffff81c47760>] ? rest_init+0x140/0x140
  [<ffffffff81c4776e>] kernel_init+0xe/0xf0
  [<ffffffff81c6be9c>] ret_from_fork+0x7c/0xb0
  [<ffffffff81c47760>] ? rest_init+0x140/0x140
  ...

v2: Typo fix in x86-32.

v3: CPU number dropped from show_regs_print_info() as
    dump_stack_print_info() has been updated to print it.  s390
    specific implementation dropped as requested by s390 maintainers.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>		[tile bits]
Acked-by: Richard Kuo <rkuo@codeaurora.org>		[hexagon bits]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30 17:04:02 -07:00
Al Viro
afa86fc426 flagday: don't pass regs to copy_thread()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-28 23:43:42 -05:00
Al Viro
1d4b4b2994 x86, um: switch to generic fork/vfork/clone
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-28 22:13:44 -05:00
Linus Torvalds
42859eea96 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull generic execve() changes from Al Viro:
 "This introduces the generic kernel_thread() and kernel_execve()
  functions, and switches x86, arm, alpha, um and s390 over to them."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (26 commits)
  s390: convert to generic kernel_execve()
  s390: switch to generic kernel_thread()
  s390: fold kernel_thread_helper() into ret_from_fork()
  s390: fold execve_tail() into start_thread(), convert to generic sys_execve()
  um: switch to generic kernel_thread()
  x86, um/x86: switch to generic sys_execve and kernel_execve
  x86: split ret_from_fork
  alpha: introduce ret_from_kernel_execve(), switch to generic kernel_execve()
  alpha: switch to generic kernel_thread()
  alpha: switch to generic sys_execve()
  arm: get rid of execve wrapper, switch to generic execve() implementation
  arm: optimized current_pt_regs()
  arm: introduce ret_from_kernel_execve(), switch to generic kernel_execve()
  arm: split ret_from_fork, simplify kernel_thread() [based on patch by rmk]
  generic sys_execve()
  generic kernel_execve()
  new helper: current_pt_regs()
  preparation for generic kernel_thread()
  um: kill thread->forking
  um: let signal_delivered() do SIGTRAP on singlestepping into handler
  ...
2012-10-10 12:02:25 +09:00
Al Viro
6783eaa2e1 x86, um/x86: switch to generic sys_execve and kernel_execve
32bit wrapper is lost on that; 64bit one is *not*, since
we need to arrange for full pt_regs on stack when we call
sys_execve() and we need to load callee-saved ones from
there afterwards.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-30 22:53:32 -04:00
Al Viro
7076aada10 x86: split ret_from_fork
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-30 22:53:31 -04:00
Al Viro
e76623d694 x86: get rid of TIF_IRET hackery
TIF_NOTIFY_RESUME will work in precisely the same way; all that
is achieved by TIF_IRET is appearing that there's some work to be
done, so we end up on the iret exit path.  Just use NOTIFY_RESUME.
And for execve() do that in 32bit start_thread(), not sys_execve()
itself.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-20 09:50:17 -04:00
Suresh Siddha
304bceda6a x86, fpu: use non-lazy fpu restore for processors supporting xsave
Fundamental model of the current Linux kernel is to lazily init and
restore FPU instead of restoring the task state during context switch.
This changes that fundamental lazy model to the non-lazy model for
the processors supporting xsave feature.

Reasons driving this model change are:

i. Newer processors support optimized state save/restore using xsaveopt and
xrstor by tracking the INIT state and MODIFIED state during context-switch.
This is faster than modifying the cr0.TS bit which has serializing semantics.

ii. Newer glibc versions use SSE for some of the optimized copy/clear routines.
With certain workloads (like boot, kernel-compilation etc), application
completes its work with in the first 5 task switches, thus taking upto 5 #DNA
traps with the kernel not getting a chance to apply the above mentioned
pre-load heuristic.

iii. Some xstate features (like AMD's LWP feature) don't honor the cr0.TS bit
and thus will not work correctly in the presence of lazy restore. Non-lazy
state restore is needed for enabling such features.

Some data on a two socket SNB system:
 * Saved 20K DNA exceptions during boot on a two socket SNB system.
 * Saved 50K DNA exceptions during kernel-compilation workload.
 * Improved throughput of the AVX based checksumming function inside the
   kernel by ~15% as xsave/xrstor is faster than the serializing clts/stts
   pair.

Also now kernel_fpu_begin/end() relies on the patched
alternative instructions. So move check_fpu() which uses the
kernel_fpu_begin/end() after alternative_instructions().

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1345842782-24175-7-git-send-email-suresh.b.siddha@intel.com
Merge 32-bit boot fix from,
Link: http://lkml.kernel.org/r/1347300665-6209-4-git-send-email-suresh.b.siddha@intel.com
Cc: Jim Kukunas <james.t.kukunas@linux.intel.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Avi Kivity <avi@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-09-18 15:52:11 -07:00
Linus Torvalds
ec0d7f18ab Merge branch 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull fpu state cleanups from Ingo Molnar:
 "This tree streamlines further aspects of FPU handling by eliminating
  the prepare_to_copy() complication and moving that logic to
  arch_dup_task_struct().

  It also fixes the FPU dumps in threaded core dumps, removes and old
  (and now invalid) assumption plus micro-optimizes the exit path by
  avoiding an FPU save for dead tasks."

Fixed up trivial add-add conflict in arch/sh/kernel/process.c that came
in because we now do the FPU handling in arch_dup_task_struct() rather
than the legacy (and now gone) prepare_to_copy().

* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, fpu: drop the fpu state during thread exit
  x86, xsave: remove thread_has_fpu() bug check in __sanitize_i387_state()
  coredump: ensure the fpu state is flushed for proper multi-threaded core dump
  fork: move the real prepare_to_copy() users to arch_dup_task_struct()
2012-05-23 10:59:07 -07:00
Suresh Siddha
55ccf3fe3f fork: move the real prepare_to_copy() users to arch_dup_task_struct()
Historical prepare_to_copy() is mostly a no-op, duplicated for majority of
the architectures and the rest following the x86 model of flushing the extended
register state like fpu there.

Remove it and use the arch_dup_task_struct() instead.

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1336692811-30576-1-git-send-email-suresh.b.siddha@intel.com
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-05-16 15:16:26 -07:00
Alex Shi
c6ae41e7d4 x86: replace percpu_xxx funcs with this_cpu_xxx
Since percpu_xxx() serial functions are duplicated with this_cpu_xxx().
Removing percpu_xxx() definition and replacing them by this_cpu_xxx()
in code. There is no function change in this patch, just preparation for
later percpu_xxx serial function removing.

On x86 machine the this_cpu_xxx() serial functions are same as
__this_cpu_xxx() without no unnecessary premmpt enable/disable.

Thanks for Stephen Rothwell, he found and fixed a i386 build error in
the patch.

Also thanks for Andrew Morton, he kept updating the patchset in Linus'
tree.

Signed-off-by: Alex Shi <alex.shi@intel.com>
Acked-by: Christoph Lameter <cl@gentwo.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2012-05-14 14:15:31 -07:00
Linus Torvalds
6b8212a313 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 updates from Ingo Molnar.

This touches some non-x86 files due to the sanitized INLINE_SPIN_UNLOCK
config usage.

Fixed up trivial conflicts due to just header include changes (removing
headers due to cpu_idle() merge clashing with the <asm/system.h> split).

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic/amd: Be more verbose about LVT offset assignments
  x86, tls: Off by one limit check
  x86/ioapic: Add io_apic_ops driver layer to allow interception
  x86/olpc: Add debugfs interface for EC commands
  x86: Merge the x86_32 and x86_64 cpu_idle() functions
  x86/kconfig: Remove CONFIG_TR=y from the defconfigs
  x86: Stop recursive fault in print_context_stack after stack overflow
  x86/io_apic: Move and reenable irq only when CONFIG_GENERIC_PENDING_IRQ=y
  x86/apic: Add separate apic_id_valid() functions for selected apic drivers
  locking/kconfig: Simplify INLINE_SPIN_UNLOCK usage
  x86/kconfig: Update defconfigs
  x86: Fix excessive MSR print out when show_msr is not specified
2012-03-29 14:28:26 -07:00
David Howells
f05e798ad4 Disintegrate asm/system.h for X86
Disintegrate asm/system.h for X86.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
cc: x86@kernel.org
2012-03-28 18:11:12 +01:00
Richard Weinberger
90e240142b x86: Merge the x86_32 and x86_64 cpu_idle() functions
Both functions are mostly identical.
The differences are:

- x86_32's cpu_idle() makes use of check_pgt_cache(), which is a
  nop on both x86_32 and x86_64.

- x86_64's cpu_idle() uses enter/__exit_idle/(), on x86_32 these
  function are a nop.

- In contrast to x86_32, x86_64 calls rcu_idle_enter/exit() in
  the innermost loop because idle notifications need RCU.
  Calling these function on x86_32 also in the innermost loop
  does not hurt.

So we can merge both functions.

Signed-off-by: Richard Weinberger <richard@nod.at>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: paulmck@linux.vnet.ibm.com
Cc: josh@joshtriplett.org
Cc: tj@kernel.org
Link: http://lkml.kernel.org/r/1332709204-22496-1-git-send-email-richard@nod.at
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-03-26 03:16:07 +02:00
Linus Torvalds
35cb8d9e18 Merge branch 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86/fpu changes from Ingo Molnar.

* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  i387: Split up <asm/i387.h> into exported and internal interfaces
  i387: Uninline the generic FP helpers that we expose to kernel modules
2012-03-22 09:41:22 -07:00
Thomas Gleixner
bd2f55361f sched/rt: Use schedule_preempt_disabled()
Coccinelle based conversion.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-24swm5zut3h9c4a6s46x8rws@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-01 10:28:03 +01:00
Linus Torvalds
1361b83a13 i387: Split up <asm/i387.h> into exported and internal interfaces
While various modules include <asm/i387.h> to get access to things we
actually *intend* for them to use, most of that header file was really
pretty low-level internal stuff that we really don't want to expose to
others.

So split the header file into two: the small exported interfaces remain
in <asm/i387.h>, while the internal definitions that are only used by
core architecture code are now in <asm/fpu-internal.h>.

The guiding principle for this was to expose functions that we export to
modules, and leave them in <asm/i387.h>, while stuff that is used by
task switching or was marked GPL-only is in <asm/fpu-internal.h>.

The fpu-internal.h file could be further split up too, especially since
arch/x86/kvm/ uses some of the remaining stuff for its module.  But that
kvm usage should probably be abstracted out a bit, and at least now the
internal FPU accessor functions are much more contained.  Even if it
isn't perhaps as contained as it _could_ be.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1202211340330.5354@i5.linux-foundation.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-02-21 14:12:54 -08:00
Linus Torvalds
7e16838d94 i387: support lazy restore of FPU state
This makes us recognize when we try to restore FPU state that matches
what we already have in the FPU on this CPU, and avoids the restore
entirely if so.

To do this, we add two new data fields:

 - a percpu 'fpu_owner_task' variable that gets written any time we
   update the "has_fpu" field, and thus acts as a kind of back-pointer
   to the task that owns the CPU.  The exception is when we save the FPU
   state as part of a context switch - if the save can keep the FPU
   state around, we leave the 'fpu_owner_task' variable pointing at the
   task whose FP state still remains on the CPU.

 - a per-thread 'last_cpu' field, that indicates which CPU that thread
   used its FPU on last.  We update this on every context switch
   (writing an invalid CPU number if the last context switch didn't
   leave the FPU in a lazily usable state), so we know that *that*
   thread has done nothing else with the FPU since.

These two fields together can be used when next switching back to the
task to see if the CPU still matches: if 'fpu_owner_task' matches the
task we are switching to, we know that no other task (or kernel FPU
usage) touched the FPU on this CPU in the meantime, and if the current
CPU number matches the 'last_cpu' field, we know that this thread did no
other FP work on any other CPU, so the FPU state on the CPU must match
what was saved on last context switch.

In that case, we can avoid the 'f[x]rstor' entirely, and just clear the
CR0.TS bit.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-20 10:58:54 -08:00
Linus Torvalds
cea20ca3f3 i387: fix up some fpu_counter confusion
This makes sure we clear the FPU usage counter for newly created tasks,
just so that we start off in a known state (for example, don't try to
preload the FPU state on the first task switch etc).

It also fixes a thinko in when we increment the fpu_counter at task
switch time, introduced by commit 34ddc81a23 ("i387: re-introduce FPU
state preloading at context switch time").  We should increment the
*new* task fpu_counter, not the old task, and only if we decide to use
that state (whether lazily or preloaded).

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-20 10:24:09 -08:00
Linus Torvalds
34ddc81a23 i387: re-introduce FPU state preloading at context switch time
After all the FPU state cleanups and finally finding the problem that
caused all our FPU save/restore problems, this re-introduces the
preloading of FPU state that was removed in commit b3b0870ef3 ("i387:
do not preload FPU state at task switch time").

However, instead of simply reverting the removal, this reimplements
preloading with several fixes, most notably

 - properly abstracted as a true FPU state switch, rather than as
   open-coded save and restore with various hacks.

   In particular, implementing it as a proper FPU state switch allows us
   to optimize the CR0.TS flag accesses: there is no reason to set the
   TS bit only to then almost immediately clear it again.  CR0 accesses
   are quite slow and expensive, don't flip the bit back and forth for
   no good reason.

 - Make sure that the same model works for both x86-32 and x86-64, so
   that there are no gratuitous differences between the two due to the
   way they save and restore segment state differently due to
   architectural differences that really don't matter to the FPU state.

 - Avoid exposing the "preload" state to the context switch routines,
   and in particular allow the concept of lazy state restore: if nothing
   else has used the FPU in the meantime, and the process is still on
   the same CPU, we can avoid restoring state from memory entirely, just
   re-expose the state that is still in the FPU unit.

   That optimized lazy restore isn't actually implemented here, but the
   infrastructure is set up for it.  Of course, older CPU's that use
   'fnsave' to save the state cannot take advantage of this, since the
   state saving also trashes the state.

In other words, there is now an actual _design_ to the FPU state saving,
rather than just random historical baggage.  Hopefully it's easier to
follow as a result.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-18 14:03:48 -08:00
Linus Torvalds
b3b0870ef3 i387: do not preload FPU state at task switch time
Yes, taking the trap to re-load the FPU/MMX state is expensive, but so
is spending several days looking for a bug in the state save/restore
code.  And the preload code has some rather subtle interactions with
both paravirtualization support and segment state restore, so it's not
nearly as simple as it should be.

Also, now that we no longer necessarily depend on a single bit (ie
TS_USEDFPU) for keeping track of the state of the FPU, we migth be able
to do better.  If we are really switching between two processes that
keep touching the FP state, save/restore is inevitable, but in the case
of having one process that does most of the FPU usage, we may actually
be able to do much better than the preloading.

In particular, we may be able to keep track of which CPU the process ran
on last, and also per CPU keep track of which process' FP state that CPU
has.  For modern CPU's that don't destroy the FPU contents on save time,
that would allow us to do a lazy restore by just re-enabling the
existing FPU state - with no restore cost at all!

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-16 15:45:23 -08:00
Frederic Weisbecker
1268fbc746 nohz: Remove tick_nohz_idle_enter_norcu() / tick_nohz_idle_exit_norcu()
Those two APIs were provided to optimize the calls of
tick_nohz_idle_enter() and rcu_idle_enter() into a single
irq disabled section. This way no interrupt happening in-between would
needlessly process any RCU job.

Now we are talking about an optimization for which benefits
have yet to be measured. Let's start simple and completely decouple
idle rcu and dyntick idle logics to simplify.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11 10:31:57 -08:00
Frederic Weisbecker
2bbb6817c0 nohz: Allow rcu extended quiescent state handling seperately from tick stop
It is assumed that rcu won't be used once we switch to tickless
mode and until we restart the tick. However this is not always
true, as in x86-64 where we dereference the idle notifiers after
the tick is stopped.

To prepare for fixing this, add two new APIs:
tick_nohz_idle_enter_norcu() and tick_nohz_idle_exit_norcu().

If no use of RCU is made in the idle loop between
tick_nohz_enter_idle() and tick_nohz_exit_idle() calls, the arch
must instead call the new *_norcu() version such that the arch doesn't
need to call rcu_idle_enter() and rcu_idle_exit().

Otherwise the arch must call tick_nohz_enter_idle() and
tick_nohz_exit_idle() and also call explicitly:

- rcu_idle_enter() after its last use of RCU before the CPU is put
to sleep.
- rcu_idle_exit() before the first use of RCU after the CPU is woken
up.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: David Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11 10:31:36 -08:00
Frederic Weisbecker
280f06774a nohz: Separate out irq exit and idle loop dyntick logic
The tick_nohz_stop_sched_tick() function, which tries to delay
the next timer tick as long as possible, can be called from two
places:

- From the idle loop to start the dytick idle mode
- From interrupt exit if we have interrupted the dyntick
idle mode, so that we reprogram the next tick event in
case the irq changed some internal state that requires this
action.

There are only few minor differences between both that
are handled by that function, driven by the ts->inidle
cpu variable and the inidle parameter. The whole guarantees
that we only update the dyntick mode on irq exit if we actually
interrupted the dyntick idle mode, and that we enter in RCU extended
quiescent state from idle loop entry only.

Split this function into:

- tick_nohz_idle_enter(), which sets ts->inidle to 1, enters
dynticks idle mode unconditionally if it can, and enters into RCU
extended quiescent state.

- tick_nohz_irq_exit() which only updates the dynticks idle mode
when ts->inidle is set (ie: if tick_nohz_idle_enter() has been called).

To maintain symmetry, tick_nohz_restart_sched_tick() has been renamed
into tick_nohz_idle_exit().

This simplifies the code and micro-optimize the irq exit path (no need
for local_irq_save there). This also prepares for the split between
dynticks and rcu extended quiescent state logics. We'll need this split to
further fix illegal uses of RCU in extended quiescent states in the idle
loop.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: David Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-12-11 10:31:35 -08:00
Linus Torvalds
7115e3fcf4 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (121 commits)
  perf symbols: Increase symbol KSYM_NAME_LEN size
  perf hists browser: Refuse 'a' hotkey on non symbolic views
  perf ui browser: Use libslang to read keys
  perf tools: Fix tracing info recording
  perf hists browser: Elide DSO column when it is set to just one DSO, ditto for threads
  perf hists: Don't consider filtered entries when calculating column widths
  perf hists: Don't decay total_period for filtered entries
  perf hists browser: Honour symbol_conf.show_{nr_samples,total_period}
  perf hists browser: Do not exit on tab key with single event
  perf annotate browser: Don't change selection line when returning from callq
  perf tools: handle endianness of feature bitmap
  perf tools: Add prelink suggestion to dso update message
  perf script: Fix unknown feature comment
  perf hists browser: Apply the dso and thread filters when merging new batches
  perf hists: Move the dso and thread filters from hist_browser
  perf ui browser: Honour the xterm colors
  perf top tui: Give color hints just on the percentage, like on --stdio
  perf ui browser: Make the colors configurable and change the defaults
  perf tui: Remove unneeded call to newtCls on startup
  perf hists: Don't format the percentage on hist_entry__snprintf
  ...

Fix up conflicts in arch/x86/kernel/kprobes.c manually.

Ingo's tree did the insane "add volatile to const array", which just
doesn't make sense ("volatile const"?).  But we could remove the const
*and* make the array volatile to make doubly sure that gcc doesn't
optimize it away..

Also fix up kernel/trace/ring_buffer.c non-data-conflicts manually: the
reader_lock has been turned into a raw lock by the core locking merge,
and there was a new user of it introduced in this perf core merge.  Make
sure that new use also uses the raw accessor functions.
2011-10-26 17:03:38 +02:00
Don Zickus
b227e23399 x86, nmi: Add in logic to handle multiple events and unknown NMIs
Previous patches allow the NMI subsystem to process multipe NMI events
in one NMI.  As previously discussed this can cause issues when an event
triggered another NMI but is processed in the current NMI.  This causes the
next NMI to go unprocessed and become an 'unknown' NMI.

To handle this, we first have to flag whether or not the NMI handler handled
more than one event or not.  If it did, then there exists a chance that
the next NMI might be already processed.  Once the NMI is flagged as a
candidate to be swallowed, we next look for a back-to-back NMI condition.

This is determined by looking at the %rip from pt_regs.  If it is the same
as the previous NMI, it is assumed the cpu did not have a chance to jump
back into a non-NMI context and execute code and instead handled another NMI.

If both of those conditions are true then we will swallow any unknown NMI.

There still exists a chance that we accidentally swallow a real unknown NMI,
but for now things seem better.

An optimization has also been added to the nmi notifier rountine.  Because x86
can latch up to one NMI while currently processing an NMI, we don't have to
worry about executing _all_ the handlers in a standalone NMI.  The idea is
if multiple NMIs come in, the second NMI will represent them.  For those
back-to-back NMI cases, we have the potentail to drop NMIs.  Therefore only
execute all the handlers in the second half of a detected back-to-back NMI.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1317409584-23662-5-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-10 06:57:01 +02:00
Jiri Kosina
e060c38434 Merge branch 'master' into for-next
Fast-forward merge with Linus to be able to merge patches
based on more recent version of the tree.
2011-09-15 15:08:18 +02:00
Kamalesh Babulal
ea70ef3d9d sched: x86_32 Fix typo in switch_to() description
This patch fixes the typo in parameters passed to
x86_32 switch_to() description.

Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-09-15 14:13:48 +02:00
Len Brown
a0bfa13738 cpuidle: stop depending on pm_idle
cpuidle users should call cpuidle_call_idle() directly
rather than via (pm_idle)() function pointer.

Architecture may choose to continue using (pm_idle)(),
but cpuidle need not depend on it:

  my_arch_cpu_idle()
	...
	if(cpuidle_call_idle())
		pm_idle();

cc: Kevin Hilman <khilman@deeprootsystems.com>
cc: Paul Mundt <lethal@linux-sh.org>
cc: x86@kernel.org
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2011-08-03 19:06:37 -04:00
Mathias Krause
dac853ae89 exec: delay address limit change until point of no return
Unconditionally changing the address limit to USER_DS and not restoring
it to its old value in the error path is wrong because it prevents us
using kernel memory on repeated calls to this function.  This, in fact,
breaks the fallback of hard coded paths to the init program from being
ever successful if the first candidate fails to load.

With this patch applied switching to USER_DS is delayed until the point
of no return is reached which makes it possible to have a multi-arch
rootfs with one arch specific init binary for each of the (hard coded)
probed paths.

Since the address limit is already set to USER_DS when start_thread()
will be invoked, this redundancy can be safely removed.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-09 12:50:05 -07:00
Thomas Renninger
f77cfe4ea2 cpuidle/x86/perf: fix power:cpu_idle double end events and throw cpu_idle events from the cpuidle layer
Currently intel_idle and acpi_idle driver show double cpu_idle "exit idle"
events -> this patch fixes it and makes cpu_idle events throwing less complex.

It also introduces cpu_idle events for all architectures which use
the cpuidle subsystem, namely:
  - arch/arm/mach-at91/cpuidle.c
  - arch/arm/mach-davinci/cpuidle.c
  - arch/arm/mach-kirkwood/cpuidle.c
  - arch/arm/mach-omap2/cpuidle34xx.c
  - arch/drivers/acpi/processor_idle.c (for all cases, not only mwait)
  - arch/x86/kernel/process.c (did throw events before, but was a mess)
  - drivers/idle/intel_idle.c (did throw events before)

Convention should be:
Fire cpu_idle events inside the current pm_idle function (not somewhere
down the the callee tree) to keep things easy.

Current possible pm_idle functions in X86:
c1e_idle, poll_idle, cpuidle_idle_call, mwait_idle, default_idle
-> this is really easy is now.

This affects userspace:
The type field of the cpu_idle power event can now direclty get
mapped to:
/sys/devices/system/cpu/cpuX/cpuidle/stateX/{name,desc,usage,time,...}
instead of throwing very CPU/mwait specific values.
This change is not visible for the intel_idle driver.
For the acpi_idle driver it should only be visible if the vendor
misses out C-states in his BIOS.
Another (perf timechart) patch reads out cpuidle info of cpu_idle
events from:
/sys/.../cpuidle/stateX/*, then the cpuidle events are mapped
to the correct C-/cpuidle state again, even if e.g. vendors miss
out C-states in their BIOS and for example only export C1 and C3.
-> everything is fine.

Signed-off-by: Thomas Renninger <trenn@suse.de>
CC: Robert Schoene <robert.schoene@tu-dresden.de>
CC: Jean Pihet <j-pihet@ti.com>
CC: Arjan van de Ven <arjan@linux.intel.com>
CC: Ingo Molnar <mingo@elte.hu>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: linux-pm@lists.linux-foundation.org
CC: linux-acpi@vger.kernel.org
CC: linux-kernel@vger.kernel.org
CC: linux-perf-users@vger.kernel.org
CC: linux-omap@vger.kernel.org
Signed-off-by: Len Brown <len.brown@intel.com>
2011-01-12 18:05:16 -05:00
Thomas Renninger
25e41933b5 perf: Clean up power events by introducing new, more generic ones
Add these new power trace events:

 power:cpu_idle
 power:cpu_frequency
 power:machine_suspend

The old C-state/idle accounting events:
  power:power_start
  power:power_end

Have now a replacement (but we are still keeping the old
tracepoints for compatibility):

  power:cpu_idle

and
  power:power_frequency

is replaced with:
  power:cpu_frequency

power:machine_suspend is newly introduced.

Jean Pihet has a patch integrated into the generic layer
(kernel/power/suspend.c) which will make use of it.

the type= field got removed from both, it was never
used and the type is differed by the event type itself.

perf timechart userspace tool gets adjusted in a separate patch.

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Jean Pihet <jean.pihet@newoldbits.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: rjw@sisk.pl
LKML-Reference: <1294073445-14812-3-git-send-email-trenn@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <1290072314-31155-2-git-send-email-trenn@suse.de>
2011-01-04 08:16:54 +01:00
Robert Schöne
c882e0feb9 x86, perf: Add power_end event to process_*.c cpu_idle routine
Systems using the idle thread from process_32.c and process_64.c
do not generate power_end events which could be traced using
perf. This patch adds the event generation for such systems.

Signed-off-by: Robert Schoene <robert.schoene@tu-dresden.de>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1276515440.5441.45.camel@localhost>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-06-18 11:35:10 +02:00
Linus Torvalds
41d59102e1 Merge branch 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, fpu: Use static_cpu_has() to implement use_xsave()
  x86: Add new static_cpu_has() function using alternatives
  x86, fpu: Use the proper asm constraint in use_xsave()
  x86, fpu: Unbreak FPU emulation
  x86: Introduce 'struct fpu' and related API
  x86: Eliminate TS_XSAVE
  x86-32: Don't set ignore_fpu_irq in simd exception
  x86: Merge kernel_math_error() into math_error()
  x86: Merge simd_math_error() into math_error()
  x86-32: Rework cache flush denied handler

Fix trivial conflict in arch/x86/kernel/process.c
2010-05-18 08:58:16 -07:00
Avi Kivity
8660328332 x86: Introduce 'struct fpu' and related API
Currently all fpu state access is through tsk->thread.xstate.  Since we wish
to generalize fpu access to non-task contexts, wrap the state in a new
'struct fpu' and convert existing access to use an fpu API.

Signal frame handlers are not converted to the API since they will remain
task context only things.

Signed-off-by: Avi Kivity <avi@redhat.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1273135546-29690-3-git-send-email-avi@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-05-10 10:48:55 -07:00
Peter Zijlstra
faa4602e47 x86, perf, bts, mm: Delete the never used BTS-ptrace code
Support for the PMU's BTS features has been upstreamed in
v2.6.32, but we still have the old and disabled ptrace-BTS,
as Linus noticed it not so long ago.

It's buggy: TIF_DEBUGCTLMSR is trampling all over that MSR without
regard for other uses (perf) and doesn't provide the flexibility
needed for perf either.

Its users are ptrace-block-step and ptrace-bts, since ptrace-bts
was never used and ptrace-block-step can be implemented using a
much simpler approach.

So axe all 3000 lines of it. That includes the *locked_memory*()
APIs in mm/mlock.c as well.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Markus Metzger <markus.t.metzger@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <20100325135413.938004390@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-26 11:33:55 +01:00
Linus Torvalds
a7f16d10b5 Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Mark atomic irq ops raw for 32bit legacy
  x86: Merge show_regs()
  x86: Macroise x86 cache descriptors
  x86-32: clean up rwsem inline asm statements
  x86: Merge asm/atomic_{32,64}.h
  x86: Sync asm/atomic_32.h and asm/atomic_64.h
  x86: Split atomic64_t functions into seperate headers
  x86-64: Modify memcpy()/memset() alternatives mechanism
  x86-64: Modify copy_user_generic() alternatives mechanism
  x86: Lift restriction on the location of FIX_BTMAP_*
  x86, core: Optimize hweight32()
2010-02-28 10:35:09 -08:00
Brian Gerst
3bef444797 x86: Merge show_regs()
Using kernel_stack_pointer() allows 32-bit and 64-bit versions to
be merged.  This is more correct for 64-bit, since the old %rsp is
always saved on the stack.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
LKML-Reference: <1263397555-27695-1-git-send-email-brgerst@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-01-13 09:23:15 -08:00
Pekka Enberg
d015a09298 x86: Use KERN_DEFAULT log-level in __show_regs()
Andrew Morton reported a strange looking kmemcheck warning:

  WARNING: kmemcheck: Caught 32-bit read from uninitialized memory (ffff88004fba6c20)
  0000000000000000310000000000000000000000000000002413000000c9ffff
   u u u u u u u u u u u u u u u u i i i i i i i i u u u u u u u u

   [<ffffffff810af3aa>] kmemleak_scan+0x25a/0x540
   [<ffffffff810afbcb>] kmemleak_scan_thread+0x5b/0xe0
   [<ffffffff8104d0fe>] kthread+0x9e/0xb0
   [<ffffffff81003074>] kernel_thread_helper+0x4/0x10
   [<ffffffffffffffff>] 0xffffffffffffffff

The above printout is missing register dump completely. The
problem here is that the output comes from syslog which doesn't
show KERN_INFO log-level messages. We didn't see this before
because both of us were testing on 32-bit kernels which use the
_default_ log-level.

Fix that up by explicitly using KERN_DEFAULT log-level for
__show_regs() printks.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <1261988819.4641.2.camel@penberg-laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-28 09:40:21 +01:00
Ingo Molnar
ab1eebe77d Merge branch 'x86/asm' into x86/urgent
Merge reason: it's stable so lets push it upstream.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-15 20:33:28 +01:00
Brian Gerst
df59e7bf43 x86: Merge kernel_thread()
Signed-off-by: Brian Gerst <brgerst@gmail.com>
LKML-Reference: <1260380084-3707-6-git-send-email-brgerst@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-12-10 16:41:31 -08:00
Brian Gerst
f443ff4201 x86: Sync 32/64-bit kernel_thread
Signed-off-by: Brian Gerst <brgerst@gmail.com>
LKML-Reference: <1260380084-3707-5-git-send-email-brgerst@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-12-10 15:55:39 -08:00
Brian Gerst
e840227c14 x86, 32-bit: Use same regs as 64-bit for kernel_thread_helper
The arg should be in %eax, but that is clobbered by the return value
of clone.  The function pointer can be in any register.  Also, don't
push args onto the stack, since regparm(3) is the normal calling
convention now.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
LKML-Reference: <1260380084-3707-4-git-send-email-brgerst@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-12-10 15:55:36 -08:00
Brian Gerst
f839bbc5c8 x86: Merge sys_clone
Change 32-bit sys_clone to new PTREGSCALL stub, and merge with 64-bit.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
LKML-Reference: <1260403316-5679-7-git-send-email-brgerst@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-12-09 16:29:42 -08:00
Brian Gerst
11cf88bd0b x86: Merge sys_execve
Change 32-bit sys_execve to PTREGSCALL3, and merge with 64-bit.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
LKML-Reference: <1260403316-5679-4-git-send-email-brgerst@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-12-09 16:28:34 -08:00
Andy Isaacson
814e2c84a7 x86: Factor duplicated code out of __show_regs() into show_regs_common()
Unify x86_32 and x86_64 implementations of __show_regs() header,
standardizing on the x86_64 format string in the process. Also,
32-bit will now call print_modules.

Signed-off-by: Andy Isaacson <adi@hexapodia.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Robert Hancock <hancockrwd@gmail.com>
Cc: Richard Zidlicky <rz@linux-m68k.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <20091208082942.GA27174@hexapodia.org>
[ v2: resolved conflict ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-09 10:17:58 +01:00
Linus Torvalds
6ec22f9b03 Merge branch 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Limit number of per cpu TSC sync messages
  x86: dumpstack, 64-bit: Disable preemption when walking the IRQ/exception stacks
  x86: dumpstack: Clean up the x86_stack_ids[][] initalization and other details
  x86, cpu: mv display_cacheinfo -> cpu_detect_cache_sizes
  x86: Suppress stack overrun message for init_task
  x86: Fix cpu_devs[] initialization in early_cpu_init()
  x86: Remove CPU cache size output for non-Intel too
  x86: Minimise printk spew from per-vendor init code
  x86: Remove the CPU cache size printk's
  cpumask: Avoid cpumask_t in arch/x86/kernel/apic/nmi.c
  x86: Make sure we also print a Code: line for show_regs()
2009-12-05 15:33:27 -08:00
Linus Torvalds
c2ed69cdc9 Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Fix a section mismatch in arch/x86/kernel/setup.c
  x86: Fixup last users of irq_chip->typename
  x86: Remove BKL from apm_32
  x86: Remove BKL from microcode
  x86: use kernel_stack_pointer() in kprobes.c
  x86: use kernel_stack_pointer() in kgdb.c
  x86: use kernel_stack_pointer() in dumpstack.c
  x86: use kernel_stack_pointer() in process_32.c
2009-12-05 15:32:18 -08:00
Frederic Weisbecker
24f1e32c60 hw-breakpoints: Rewrite the hw-breakpoints layer on top of perf events
This patch rebase the implementation of the breakpoints API on top of
perf events instances.

Each breakpoints are now perf events that handle the
register scheduling, thread/cpu attachment, etc..

The new layering is now made as follows:

       ptrace       kgdb      ftrace   perf syscall
          \          |          /         /
           \         |         /         /
                                        /
            Core breakpoint API        /
                                      /
                     |               /
                     |              /

              Breakpoints perf events

                     |
                     |

               Breakpoints PMU ---- Debug Register constraints handling
                                    (Part of core breakpoint API)
                     |
                     |

             Hardware debug registers

Reasons of this rewrite:

- Use the centralized/optimized pmu registers scheduling,
  implying an easier arch integration
- More powerful register handling: perf attributes (pinned/flexible
  events, exclusive/non-exclusive, tunable period, etc...)

Impact:

- New perf ABI: the hardware breakpoints counters
- Ptrace breakpoints setting remains tricky and still needs some per
  thread breakpoints references.

Todo (in the order):

- Support breakpoints perf counter events for perf tools (ie: implement
  perf_bpcounter_event())
- Support from perf tools

Changes in v2:

- Follow the perf "event " rename
- The ptrace regression have been fixed (ptrace breakpoint perf events
  weren't released when a task ended)
- Drop the struct hw_breakpoint and store generic fields in
  perf_event_attr.
- Separate core and arch specific headers, drop
  asm-generic/hw_breakpoint.h and create linux/hw_breakpoint.h
- Use new generic len/type for breakpoint
- Handle off case: when breakpoints api is not supported by an arch

Changes in v3:

- Fix broken CONFIG_KVM, we need to propagate the breakpoint api
  changes to kvm when we exit the guest and restore the bp registers
  to the host.

Changes in v4:

- Drop the hw_breakpoint_restore() stub as it is only used by KVM
- EXPORT_SYMBOL_GPL hw_breakpoint_restore() as KVM can be built as a
  module
- Restore the breakpoints unconditionally on kvm guest exit:
  TIF_DEBUG_THREAD doesn't anymore cover every cases of running
  breakpoints and vcpu->arch.switch_db_regs might not always be
  set when the guest used debug registers.
  (Waiting for a reliable optimization)

Changes in v5:

- Split-up the asm-generic/hw-breakpoint.h moving to
  linux/hw_breakpoint.h into a separate patch
- Optimize the breakpoints restoring while switching from kvm guest
  to host. We only want to restore the state if we have active
  breakpoints to the host, otherwise we don't care about messed-up
  address registers.
- Add asm/hw_breakpoint.h to Kbuild
- Fix bad breakpoint type in trace_selftest.c

Changes in v6:

- Fix wrong header inclusion in trace.h (triggered a build
  error with CONFIG_FTRACE_SELFTEST

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jan Kiszka <jan.kiszka@web.de>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Paul Mundt <lethal@linux-sh.org>
2009-11-08 15:34:42 +01:00
Arjan van de Ven
a489ca355e x86: Make sure we also print a Code: line for show_regs()
show_regs() is called as a mini BUG() equivalent in some places,
specifically for the "scheduling while atomic" case.

Unfortunately right now it does not print a Code: line unlike
a real bug/oops.

This patch changes the x86 implementation of show_regs() so that
it calls the same function as oopses do to print the registers
as well as the Code: line.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
LKML-Reference: <20091102165915.4a980fc0@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-03 16:50:22 +01:00
H. Peter Anvin
def3c5d0a3 x86: use kernel_stack_pointer() in process_32.c
The way to obtain a kernel-mode stack pointer from a struct pt_regs in
32-bit mode is "subtle": the stack doesn't actually contain the stack
pointer, but rather the location where it would have been marks the
actual previous stack frame.  For clarity, use kernel_stack_pointer()
instead of coding this weirdness explicitly.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-10-12 14:19:34 -07:00
Ingo Molnar
dca2d6ac09 Merge branch 'linus' into tracing/hw-breakpoints
Conflicts:
	arch/x86/kernel/process_64.c

Semantic conflict fixed in:
	arch/x86/kvm/x86.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 12:18:15 +02:00
Linus Torvalds
55e0715f61 Merge branch 'x86-percpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-percpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, percpu: Collect hot percpu variables into one cacheline
  x86, percpu: Fix DECLARE/DEFINE_PER_CPU_PAGE_ALIGNED()
  x86, percpu: Add 'percpu_read_stable()' interface for cacheable accesses
2009-09-14 08:01:28 -07:00
Tejun Heo
bdf977b374 x86, percpu: Collect hot percpu variables into one cacheline
On x86_64, percpu variables current_task and kernel_stack are used for
get_current() and current_thread_info() respectively and thus are
often used close to each other.  Move definition of current_task to
kernel/cpu/common.c right above kernel_stack definition and align it
to cacheline so that they always fall into the same cacheline.  Two
percpu variables defined there together - irq_stack_ptr and irq_count
- are also pretty hot and will benefit from sharing the cacheline.

For consistency, current_task definition for x86_32 is also moved to
kernel/cpu/common.c.

Putting current_task and kernel_stack into the same cacheline was
suggested by Linus Torvalds.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-04 01:29:34 +09:00
Jeremy Fitzhardinge
2fcddce10f x86-32: make sure clts is batched during context switch
If we're preloading the fpu state during context switch, make sure the clts
happens while we're batching the cpu context update, then do the actual
__math_state_restore once the updates are flushed.

This allows more efficient context switches when running paravirtualized,
as all the hypercalls can be folded together into one.

[ Impact: optimise paravirtual FPU context switch ]

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
2009-06-17 13:21:25 -07:00
Ingo Molnar
eadb8a091b Merge branch 'linus' into tracing/hw-breakpoints
Conflicts:
	arch/x86/Kconfig
	arch/x86/kernel/traps.c
	arch/x86/power/cpu.c
	arch/x86/power/cpu_32.c
	kernel/Makefile

Semantic conflict:
	arch/x86/kernel/hw_breakpoint.c

Merge reason: Resolve the conflicts, move from put_cpu_no_sched() to
              put_cpu() in arch/x86/kernel/hw_breakpoint.c.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-06-17 12:56:49 +02:00
Linus Torvalds
8623661180 Merge branch 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (244 commits)
  Revert "x86, bts: reenable ptrace branch trace support"
  tracing: do not translate event helper macros in print format
  ftrace/documentation: fix typo in function grapher name
  tracing/events: convert block trace points to TRACE_EVENT(), fix !CONFIG_BLOCK
  tracing: add protection around module events unload
  tracing: add trace_seq_vprint interface
  tracing: fix the block trace points print size
  tracing/events: convert block trace points to TRACE_EVENT()
  ring-buffer: fix ret in rb_add_time_stamp
  ring-buffer: pass in lockdep class key for reader_lock
  tracing: add annotation to what type of stack trace is recorded
  tracing: fix multiple use of __print_flags and __print_symbolic
  tracing/events: fix output format of user stack
  tracing/events: fix output format of kernel stack
  tracing/trace_stack: fix the number of entries in the header
  ring-buffer: discard timestamps that are at the start of the buffer
  ring-buffer: try to discard unneeded timestamps
  ring-buffer: fix bug in ring_buffer_discard_commit
  ftrace: do not profile functions when disabled
  tracing: make trace pipe recognize latency format flag
  ...
2009-06-10 19:53:40 -07:00
Linus Torvalds
be15f9d63b Merge branch 'x86-xen-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-xen-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (42 commits)
  xen: cache cr0 value to avoid trap'n'emulate for read_cr0
  xen/x86-64: clean up warnings about IST-using traps
  xen/x86-64: fix breakpoints and hardware watchpoints
  xen: reserve Xen start_info rather than e820 reserving
  xen: add FIX_TEXT_POKE to fixmap
  lguest: update lazy mmu changes to match lguest's use of kvm hypercalls
  xen: honour VCPU availability on boot
  xen: add "capabilities" file
  xen: drop kexec bits from /sys/hypervisor since kexec isn't implemented yet
  xen/sys/hypervisor: change writable_pt to features
  xen: add /sys/hypervisor support
  xen/xenbus: export xenbus_dev_changed
  xen: use device model for suspending xenbus devices
  xen: remove suspend_cancel hook
  xen/dev-evtchn: clean up locking in evtchn
  xen: export ioctl headers to userspace
  xen: add /dev/xen/evtchn driver
  xen: add irq_from_evtchn
  xen: clean up gate trap/interrupt constants
  xen: set _PAGE_NX in __supported_pte_mask before pagetable construction
  ...
2009-06-10 16:16:27 -07:00
K.Prasad
66cb591729 hw-breakpoints: use the new wrapper routines to access debug registers in process/thread code
This patch enables the use of abstract debug registers in
process-handling routines, according to the new hardware breakpoint
Api.

[ Impact: adapt thread breakpoints handling code to the new breakpoint Api ]

Original-patch-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-06-02 22:46:59 +02:00
Amerigo Wang
bf78ad69cd x86: process.c, remove useless headers
<stdarg.h> is not needed by these files, remove them.

[ Impact: cleanup ]

Signed-off-by: WANG Cong <amwang@redhat.com>
Cc: akpm@linux-foundation.org
LKML-Reference: <20090512032956.5040.77055.sendpatchset@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-12 11:26:32 +02:00
Amerigo Wang
9d62dcdfa6 x86: merge process.c a bit
Merge arch_align_stack() and arch_randomize_brk(), since
they are the same.

Tested on x86_64.

[ Impact: cleanup ]

Signed-off-by: Amerigo Wang <amwang@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-12 11:13:45 +02:00
Jeremy Fitzhardinge
38f4b8c0da Merge commit 'origin/master' into for-linus/xen/master
* commit 'origin/master': (4825 commits)
  Fix build errors due to CONFIG_BRANCH_TRACER=y
  parport: Use the PCI IRQ if offered
  tty: jsm cleanups
  Adjust path to gpio headers
  KGDB_SERIAL_CONSOLE check for module
  Change KCONFIG name
  tty: Blackin CTS/RTS
  Change hardware flow control from poll to interrupt driven
  Add support for the MAX3100 SPI UART.
  lanana: assign a device name and numbering for MAX3100
  serqt: initial clean up pass for tty side
  tty: Use the generic RS485 ioctl on CRIS
  tty: Correct inline types for tty_driver_kref_get()
  splice: fix deadlock in splicing to file
  nilfs2: support nanosecond timestamp
  nilfs2: introduce secondary super block
  nilfs2: simplify handling of active state of segments
  nilfs2: mark minor flag for checkpoint created by internal operation
  nilfs2: clean up sketch file
  nilfs2: super block operations fix endian bug
  ...

Conflicts:
	arch/x86/include/asm/thread_info.h
	arch/x86/lguest/boot.c
	drivers/xen/manage.c
2009-04-07 13:34:16 -07:00
Markus Metzger
2311f0de21 x86, ds: add leakage warning
Add a warning in case a debug store context is not removed before
the task it is attached to is freed.

Remove the old warning at thread exit. It is too early.

Declare the debug store context field in thread_struct unconditionally.

Remove ds_copy_thread() and ds_exit_thread() and do the work directly
in process*.c.

Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Cc: roland@redhat.com
Cc: eranian@googlemail.com
Cc: oleg@redhat.com
Cc: juan.villacis@intel.com
Cc: ak@linux.jf.intel.com
LKML-Reference: <20090403144601.254472000@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-07 13:36:28 +02:00
Alexey Dobriyan
6f2c55b843 Simplify copy_thread()
First argument unused since 2.3.11.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02 19:04:51 -07:00
Jeremy Fitzhardinge
224101ed69 x86/paravirt: finish change from lazy cpu to context switch start/end
Impact: fix lazy context switch API

Pass the previous and next tasks into the context switch start
end calls, so that the called functions can properly access the
task state (esp in end_context_switch, in which the next task
is not yet completely current).

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
2009-03-29 23:36:01 -07:00
Jeremy Fitzhardinge
7fd7d83d49 x86/pvops: replace arch_enter_lazy_cpu_mode with arch_start_context_switch
Impact: simplification, prepare for later changes

Make lazy cpu mode more specific to context switching, so that
it makes sense to do more context-switch specific things in
the callbacks.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
2009-03-29 23:35:59 -07:00