freebsd-dev/sys/x86/include
Mark Johnston 2bed14192c pvclock: Export a vDSO page even without rdtscp available
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
2023-02-03 11:48:25 -05:00
..
xen xen/blkback: do not use x86 CPUID in generic code 2022-06-28 09:51:57 +02:00
_align.h
_inttypes.h
_limits.h
_stdint.h
_types.h
acpica_machdep.h
apicreg.h
apicvar.h Increase MAX_APIC_ID safeguard to 0x800 2022-10-27 12:33:34 -04:00
apm_bios.h
bus_dma.h
bus.h Remove checks for __GNUCLIKE_ASM assuming it is always true. 2022-04-12 10:05:45 -07:00
busdma_impl.h bus_dma: Deduplicate locking helper functions. 2022-01-05 13:50:40 -08:00
clock.h x86: Probe the TSC frequency earlier 2022-03-01 09:39:35 -05:00
cputypes.h
dump.h minidump: De-duplicate the progress bar 2021-09-29 16:42:21 -03:00
elf.h x86/include/elf.h: make inclusion blocks for elf32.h and elf64.h similar 2022-10-25 19:00:44 +03:00
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 pvclock: Export a vDSO page even without rdtscp available 2023-02-03 11:48:25 -05:00
reg.h x86: Add a NT_X86_SEGBASES register set. 2022-03-24 11:36:19 -07:00
segments.h
setjmp.h
sigframe.h
signal.h
specialreg.h x86: add more definitions for XCR0 bits 2023-01-27 19:44:49 +02:00
stack.h
stdarg.h
sysarch.h
tls.h Add <machine/tls.h> header to hold MD constants and helpers for TLS. 2021-12-09 13:17:13 -08:00
trap.h x86: remove unused T_USER flag 2021-12-05 11:12:40 -04:00
ucode.h
ucontext.h
vdso.h
vmware.h
x86_ieeefp.h Remove checks for <sys/cdefs.h> being included. 2022-04-12 10:06:18 -07:00
x86_smp.h amd64: Reduce the amount of cpuset copying done for TLB shootdowns 2021-11-15 13:01:31 -05:00
x86_var.h amd64: Eliminate write only cpu_fxsr. 2023-02-01 18:17:06 +03:00