When the cycle counter is "stable", i.e., synchronized across vCPUs by the hypervisor, userspace can use a serialized rdtsc instead of relying on rdtscp, just like the kernel timecounter does. This can be useful for performance in guests where the hypervisor hides rdtscp for some reason. To avoid breaking compatibility with older userspace which expects rdtscp to be usable when pvclock exports timekeeping info, hide this feature behind a sysctl. Reviewed by: kib Tested by: Shrikanth R Kamath <kshrikanth@juniper.net> MFC after: 2 weeks Sponsored by: Klara, Inc. Sponsored by: Juniper Networks, Inc. Differential Revision: https://reviews.freebsd.org/D38342 |
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.. | ||
xen | ||
_align.h | ||
_inttypes.h | ||
_limits.h | ||
_stdint.h | ||
_types.h | ||
acpica_machdep.h | ||
apicreg.h | ||
apicvar.h | ||
apm_bios.h | ||
bus_dma.h | ||
bus.h | ||
busdma_impl.h | ||
clock.h | ||
cputypes.h | ||
dump.h | ||
elf.h | ||
endian.h | ||
fdt.h | ||
float.h | ||
fpu.h | ||
frame.h | ||
ifunc.h | ||
init.h | ||
intr_machdep.h | ||
iommu.h | ||
kvm.h | ||
legacyvar.h | ||
mca.h | ||
metadata.h | ||
mptable.h | ||
ofw_machdep.h | ||
pci_cfgreg.h | ||
procctl.h | ||
psl.h | ||
ptrace.h | ||
pvclock.h | ||
reg.h | ||
segments.h | ||
setjmp.h | ||
sigframe.h | ||
signal.h | ||
specialreg.h | ||
stack.h | ||
stdarg.h | ||
sysarch.h | ||
tls.h | ||
trap.h | ||
ucode.h | ||
ucontext.h | ||
vdso.h | ||
vmware.h | ||
x86_ieeefp.h | ||
x86_smp.h | ||
x86_var.h |