linux-toradex.git/arch/x86/kernel/tsc.c, branch v3.2

Merge branches 'x86-detect-hyper-for-linus', 'x86-fpu-for-linus', 'x86-kexec-for-linus', 'x86-platform-for-linus', 'x86-quirks-for-linus', 'x86-tsc-for-linus' and 'x86-smpboot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2011-07-23T17:38:21+00:00

* 'x86-detect-hyper-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, hyper: Change hypervisor detection order

* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86-32, fpu: Fix DNA exception during check_fpu()

* 'x86-kexec-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  kexec, x86: Fix incorrect jump back address if not preserving context

* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, config: Introduce an INTEL_MID configuration

* 'x86-quirks-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, quirks: Use pci_dev->revision

* 'x86-tsc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: tsc: Remove unneeded DMI-based blacklisting

* 'x86-smpboot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, boot: Wait for boot cpu to show up if nr_cpus limit is about to hit

x86-64: Move vread_tsc and vread_hpet into the vDSO

2011-07-15T00:57:05+00:00

The vsyscall page now consists entirely of trap instructions.

Cc: John Stultz 
Signed-off-by: Andy Lutomirski 
Link: http://lkml.kernel.org/r/637648f303f2ef93af93bae25186e9a1bea093f5.1310639973.git.luto@mit.edu
Signed-off-by: H. Peter Anvin

clocksource: Replace vread with generic arch data

2011-07-13T18:23:12+00:00

The vread field was bloating struct clocksource everywhere except
x86_64, and I want to change the way this works on x86_64, so let's
split it out into per-arch data.

Cc: x86@kernel.org
Cc: Clemens Ladisch 
Cc: linux-ia64@vger.kernel.org
Cc: Tony Luck 
Cc: Fenghua Yu 
Cc: John Stultz 
Cc: Thomas Gleixner 
Signed-off-by: Andy Lutomirski 
Link: http://lkml.kernel.org/r/3ae5ec76a168eaaae63f08a2a1060b91aa0b7759.1310563276.git.luto@mit.edu
Signed-off-by: H. Peter Anvin

x86: tsc: Remove unneeded DMI-based blacklisting

2011-06-01T06:19:51+00:00

The blacklist was added in response to my bug report
(http://lkml.org/lkml/2006/1/19/362) and has never
contained more than the one entry describing my old
now dead ThinkPad 380XD laptop. As found out later
(http://lkml.org/lkml/2007/11/29/50), this special
treatment has been unnecessary for a long time, so
it can be removed.

Signed-off-by: Tero Roponen 
Signed-off-by: John Stultz

x86-64: Move vread_tsc into a new file with sensible options

2011-05-24T12:51:29+00:00

vread_tsc is short and hot, and it's userspace code so the usual
reasons to enable -pg and turn off sibling calls don't apply.

(OK, turning off sibling calls has no effect.  But it might
someday...)

As an added benefit, tsc.c is profilable now.

Signed-off-by: Andy Lutomirski 
Cc: Andi Kleen 
Cc: Linus Torvalds 
Cc: "David S. Miller" 
Cc: Eric Dumazet 
Cc: Peter Zijlstra 
Cc: Borislav Petkov 
Link: http://lkml.kernel.org/r/%3C99c6d7f5efa3ccb65b4ac6eb443e1ab7bad47d7b.1306156808.git.luto%40mit.edu%3E
Signed-off-by: Thomas Gleixner

x86-64: Don't generate cmov in vread_tsc

2011-05-24T12:51:28+00:00

vread_tsc checks whether rdtsc returns something less than
cycle_last, which is an extremely predictable branch.  GCC likes
to generate a cmov anyway, which is several cycles slower than
a predicted branch.  This saves a couple of nanoseconds.

Signed-off-by: Andy Lutomirski 
Cc: Andi Kleen 
Cc: Linus Torvalds 
Cc: "David S. Miller" 
Cc: Eric Dumazet 
Cc: Peter Zijlstra 
Cc: Borislav Petkov 
Link: http://lkml.kernel.org/r/%3C561280649519de41352fcb620684dfb22bad6bac.1306156808.git.luto%40mit.edu%3E
Signed-off-by: Thomas Gleixner

x86-64: Remove unnecessary barrier in vread_tsc

2011-05-24T12:51:28+00:00

RDTSC is completely unordered on modern Intel and AMD CPUs.  The
Intel manual says that lfence;rdtsc causes all previous instructions
to complete before the tsc is read, and the AMD manual says to use
mfence;rdtsc to do the same thing.

From a decent amount of testing [1] this is enough to make rdtsc
be ordered with respect to subsequent loads across a wide variety
of CPUs.

On Sandy Bridge (i7-2600), this improves a loop of
clock_gettime(CLOCK_MONOTONIC) by more than 5 ns/iter.

[1] https://lkml.org/lkml/2011/4/18/350

Signed-off-by: Andy Lutomirski 
Cc: Andi Kleen 
Cc: Linus Torvalds 
Cc: "David S. Miller" 
Cc: Eric Dumazet 
Cc: Peter Zijlstra 
Cc: Borislav Petkov 
Link: http://lkml.kernel.org/r/%3C1c158b9d74338aa5361f96dd473d0e6a58235302.1306156808.git.luto%40mit.edu%3E
Signed-off-by: Thomas Gleixner

x86-64: Clean up vdso/kernel shared variables

2011-05-24T12:51:28+00:00

Variables that are shared between the vdso and the kernel are
currently a bit of a mess.  They are each defined with their own
magic, they are accessed differently in the kernel, the vsyscall page,
and the vdso, and one of them (vsyscall_clock) doesn't even really
exist.

This changes them all to use a common mechanism.  All of them are
delcared in vvar.h with a fixed address (validated by the linker
script).  In the kernel (as before), they look like ordinary
read-write variables.  In the vsyscall page and the vdso, they are
accessed through a new macro VVAR, which gives read-only access.

The vdso is now loaded verbatim into memory without any fixups.  As a
side bonus, access from the vdso is faster because a level of
indirection is removed.

While we're at it, pack jiffies and vgetcpu_mode into the same
cacheline.

Signed-off-by: Andy Lutomirski 
Cc: Andi Kleen 
Cc: Linus Torvalds 
Cc: "David S. Miller" 
Cc: Eric Dumazet 
Cc: Peter Zijlstra 
Cc: Borislav Petkov 
Link: http://lkml.kernel.org/r/%3C7357882fbb51fa30491636a7b6528747301b7ee9.1306156808.git.luto%40mit.edu%3E
Signed-off-by: Thomas Gleixner

x86: Fix common misspellings

2011-03-18T09:39:30+00:00

They were generated by 'codespell' and then manually reviewed.

Signed-off-by: Lucas De Marchi 
Cc: trivial@kernel.org
LKML-Reference: <1300389856-1099-3-git-send-email-lucas.demarchi@profusion.mobi>
Signed-off-by: Ingo Molnar

Merge branches 'core-fixes-for-linus', 'x86-fixes-for-linus', 'timers-fixes-for-linus' and 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2011-01-15T20:45:00+00:00

* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  rcu: avoid pointless blocked-task warnings
  rcu: demote SRCU_SYNCHRONIZE_DELAY from kernel-parameter status
  rtmutex: Fix comment about why new_owner can be NULL in wake_futex_pi()

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, olpc: Add missing Kconfig dependencies
  x86, mrst: Set correct APB timer IRQ affinity for secondary cpu
  x86: tsc: Fix calibration refinement conditionals to avoid divide by zero
  x86, ia64, acpi: Clean up x86-ism in drivers/acpi/numa.c

* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  timekeeping: Make local variables static
  time: Rename misnamed minsec argument of clocks_calc_mult_shift()

* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing: Remove syscall_exit_fields
  tracing: Only process module tracepoints once
  perf record: Add "nodelay" mode, disabled by default
  perf sched: Fix list of events, dropping unsupported ':r' modifier
  Revert "perf tools: Emit clearer message for sys_perf_event_open ENOENT return"
  perf top: Fix annotate segv
  perf evsel: Fix order of event list deletion