linux/arch/x86
David Vrabel 5584880e44 x86: xen: Sync the wallclock when the system time is set
Currently the Xen wallclock is only updated every 11 minutes if NTP is
synchronized to its clock source (using the sync_cmos_clock() work).
If a guest is started before NTP is synchronized it may see an
incorrect wallclock time.

Use the pvclock_gtod notifier chain to receive a notification when the
system time has changed and update the wallclock to match.

This chain is called on every timer tick and we want to avoid an extra
(expensive) hypercall on every tick.  Because dom0 has historically
never provided a very accurate wallclock and guests do not expect one,
we can do this simply: the wallclock is only updated if the clock was
set.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: <xen-devel@lists.xen.org>
Link: http://lkml.kernel.org/r/1372329348-20841-5-git-send-email-david.vrabel@citrix.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-06-28 23:15:06 +02:00
..
boot Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-04-30 08:34:07 -07:00
configs x86: Default to ARCH=x86 to avoid overriding CONFIG_64BIT 2012-12-20 14:37:18 -08:00
crypto crypto: camellia - add AVX2/AES-NI/x86_64 assembler implementation of camellia cipher 2013-04-25 21:09:07 +08:00
ia32 unify compat fanotify_mark(2), switch to COMPAT_SYSCALL_DEFINE 2013-05-09 13:46:38 -04:00
include x86: Fix vrtc_get_time/set_mmss to use new timespec interface 2013-05-29 12:57:35 -07:00
kernel x86: Increase precision of x86_platform.get/set_wallclock() 2013-05-28 14:00:59 -07:00
kvm KVM: emulator: emulate SALC 2013-05-09 13:15:08 +03:00
lguest x86: Increase precision of x86_platform.get/set_wallclock() 2013-05-28 14:00:59 -07:00
lib Kconfig: consolidate CONFIG_DEBUG_STRICT_USER_COPY_CHECKS 2013-04-30 17:04:09 -07:00
math-emu
mm x86/mm: Add missing comments for initial kernel direct mapping 2013-05-10 12:00:35 +02:00
net filter: bpf_jit_comp: refactor and unify BPF JIT image dump output 2013-03-21 17:25:56 -04:00
oprofile
pci Bug-fixes: 2013-05-11 16:19:30 -07:00
platform x86: Fix vrtc_get_time/set_mmss to use new timespec interface 2013-05-29 12:57:35 -07:00
power x86, gdt, hibernate: Store/load GDT for hibernate path. 2013-05-02 11:27:35 -07:00
realmode x86, relocs: Refactor the relocs tool to merge 32- and 64-bit ELF 2013-04-16 16:02:58 -07:00
syscalls unify compat fanotify_mark(2), switch to COMPAT_SYSCALL_DEFINE 2013-05-09 13:46:38 -04:00
tools x86, relocs: Refactor the relocs tool to merge 32- and 64-bit ELF 2013-04-16 16:02:58 -07:00
um make SYSCALL_DEFINE<n>-generated wrappers do asmlinkage_protect 2013-03-03 22:58:33 -05:00
vdso timers/x86/hpet: Use HPET_COUNTER to specify the hpet counter in vread_hpet() 2013-02-15 12:13:18 +01:00
video
xen x86: xen: Sync the wallclock when the system time is set 2013-06-28 23:15:06 +02:00
.gitignore
Kbuild
Kconfig Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-05-15 14:05:17 -07:00
Kconfig.cpu
Kconfig.debug Kconfig: consolidate CONFIG_DEBUG_STRICT_USER_COPY_CHECKS 2013-04-30 17:04:09 -07:00
Makefile Merge branch 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-02-19 19:12:03 -08:00
Makefile_32.cpu
Makefile.um