[PATCH v3 0/3] reduce TSC deadline frequency errors

[Nicolai Stange <nicstange@gmail.com>]

This series is a split-off of the x86/TSC related patches from the
"avoid double timer interrupt with nohz and Intel TSC" v2 series
(http://lkml.kernel.org/g/20160710193047.18320-1-nicstange@gmail.com).

It turned out that the non-x86 related parts of the aforementioned series
are more than arguable and I don't want to bother you with any further
discussion of those. I apologize for any confusion this split might cause.

Applicable to linux-next-20160712. The individual patches don't depend on
each other.

Changes to v2:
  - [3/3] ("arch, x86, tsc: inform TSC deadline clockevent device about
            recalibration")
    Use clockevents_update_freq() rather than clockevents_config().

  - Former [4/4] ("kernel/time/clockevents: compensate for monotonic
                   clock's dynamic frequency")
    Split off, not a member of this series anymore.

Changes to v1:
  - [1/3] ("arch, x86, tsc deadline clockevent dev: reduce frequency
            roundoff error")
      No changes to the patch. Note that the v1 mail could not be delivered
      to the author of the TSC_DIVISOR introducing commit 279f1461432c
      ("x86: apic: Use tsc deadline for oneshot when available"),
      Suresh Siddha <suresh.b.siddha@intel.com>, so I had to remove him
      from the CC list.

  - [2/3] ("arch, x86, tsc deadline clockevent dev: reduce TSC_DIVISOR
            to 2")
      Likewise.

  - [3/3] ("arch, x86, tsc: inform TSC deadline clockevent device about
            recalibration")
      Silence the kbuild test robot on ARCH=i386 by wrapping the new call
      to lapic_update_tsc_freq() from arch/x86/kernel/tsc.c in an
      #ifdef CONFIG_X86_LOCAL_APIC.

Nicolai Stange (3):
  arch, x86, tsc deadline clockevent dev: reduce frequency roundoff
    error
  arch, x86, tsc deadline clockevent dev: reduce TSC_DIVISOR to 2
  arch, x86, tsc: inform TSC deadline clockevent device about
    recalibration

 arch/x86/include/asm/apic.h |  1 +
 arch/x86/kernel/apic/apic.c | 30 ++++++++++++++++++++++++++++--
 arch/x86/kernel/tsc.c       |  6 ++++++
 3 files changed, 35 insertions(+), 2 deletions(-)

-- 
2.9.0