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authorLinus Torvalds <torvalds@linux-foundation.org>2012-12-13 15:31:08 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-13 15:31:08 -0800
commit66cdd0ceaf65a18996f561b770eedde1d123b019 (patch)
tree4892eaa422d366fce5d1e866ff1fe0988af95569 /kernel/time/timekeeping.c
parent896ea17d3da5f44b2625c9cda9874d7dfe447393 (diff)
parent58b7825bc324da55415034a9f6ca5d716b8fd898 (diff)
Merge tag 'kvm-3.8-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Marcelo Tosatti: "Considerable KVM/PPC work, x86 kvmclock vsyscall support, IA32_TSC_ADJUST MSR emulation, amongst others." Fix up trivial conflict in kernel/sched/core.c due to cross-cpu migration notifier added next to rq migration call-back. * tag 'kvm-3.8-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (156 commits) KVM: emulator: fix real mode segment checks in address linearization VMX: remove unneeded enable_unrestricted_guest check KVM: VMX: fix DPL during entry to protected mode x86/kexec: crash_vmclear_local_vmcss needs __rcu kvm: Fix irqfd resampler list walk KVM: VMX: provide the vmclear function and a bitmap to support VMCLEAR in kdump x86/kexec: VMCLEAR VMCSs loaded on all cpus if necessary KVM: MMU: optimize for set_spte KVM: PPC: booke: Get/set guest EPCR register using ONE_REG interface KVM: PPC: bookehv: Add EPCR support in mtspr/mfspr emulation KVM: PPC: bookehv: Add guest computation mode for irq delivery KVM: PPC: Make EPCR a valid field for booke64 and bookehv KVM: PPC: booke: Extend MAS2 EPN mask for 64-bit KVM: PPC: e500: Mask MAS2 EPN high 32-bits in 32/64 tlbwe emulation KVM: PPC: Mask ea's high 32-bits in 32/64 instr emulation KVM: PPC: e500: Add emulation helper for getting instruction ea KVM: PPC: bookehv64: Add support for interrupt handling KVM: PPC: bookehv: Remove GET_VCPU macro from exception handler KVM: PPC: booke: Fix get_tb() compile error on 64-bit KVM: PPC: e500: Silence bogus GCC warning in tlb code ...
Diffstat (limited to 'kernel/time/timekeeping.c')
-rw-r--r--kernel/time/timekeeping.c50
1 files changed, 50 insertions, 0 deletions
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 4c7de02eacd..cbc6acb0db3 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -21,6 +21,7 @@
#include <linux/time.h>
#include <linux/tick.h>
#include <linux/stop_machine.h>
+#include <linux/pvclock_gtod.h>
static struct timekeeper timekeeper;
@@ -174,6 +175,54 @@ static inline s64 timekeeping_get_ns_raw(struct timekeeper *tk)
return nsec + arch_gettimeoffset();
}
+static RAW_NOTIFIER_HEAD(pvclock_gtod_chain);
+
+static void update_pvclock_gtod(struct timekeeper *tk)
+{
+ raw_notifier_call_chain(&pvclock_gtod_chain, 0, tk);
+}
+
+/**
+ * pvclock_gtod_register_notifier - register a pvclock timedata update listener
+ *
+ * Must hold write on timekeeper.lock
+ */
+int pvclock_gtod_register_notifier(struct notifier_block *nb)
+{
+ struct timekeeper *tk = &timekeeper;
+ unsigned long flags;
+ int ret;
+
+ write_seqlock_irqsave(&tk->lock, flags);
+ ret = raw_notifier_chain_register(&pvclock_gtod_chain, nb);
+ /* update timekeeping data */
+ update_pvclock_gtod(tk);
+ write_sequnlock_irqrestore(&tk->lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pvclock_gtod_register_notifier);
+
+/**
+ * pvclock_gtod_unregister_notifier - unregister a pvclock
+ * timedata update listener
+ *
+ * Must hold write on timekeeper.lock
+ */
+int pvclock_gtod_unregister_notifier(struct notifier_block *nb)
+{
+ struct timekeeper *tk = &timekeeper;
+ unsigned long flags;
+ int ret;
+
+ write_seqlock_irqsave(&tk->lock, flags);
+ ret = raw_notifier_chain_unregister(&pvclock_gtod_chain, nb);
+ write_sequnlock_irqrestore(&tk->lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pvclock_gtod_unregister_notifier);
+
/* must hold write on timekeeper.lock */
static void timekeeping_update(struct timekeeper *tk, bool clearntp)
{
@@ -182,6 +231,7 @@ static void timekeeping_update(struct timekeeper *tk, bool clearntp)
ntp_clear();
}
update_vsyscall(tk);
+ update_pvclock_gtod(tk);
}
/**