linux/arch/x86/kernel
Daniel Vacek a786ef152c x86/tsc: Make calibration refinement more robust
The threshold in tsc_read_refs() is constant which may favor slower CPUs
but may not be optimal for simple reading of reference on faster ones.

Hence make it proportional to tsc_khz when available to compensate for
this. The threshold guards against any disturbance like IRQs, NMIs, SMIs
or CPU stealing by host on guest systems so rename it accordingly and
fix comments as well.

Also on some systems there is noticeable DMI bus contention at some point
during boot keeping the readout failing (observed with about one in ~300
boots when testing). In that case retry also the second readout instead of
simply bailing out unrefined. Usually the next second the readout returns
fast just fine without any issues.

Signed-off-by: Daniel Vacek <neelx@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/1541437840-29293-1-git-send-email-neelx@redhat.com
2018-11-06 21:53:15 +01:00
..
acpi memblock: stop using implicit alignment to SMP_CACHE_BYTES 2018-10-31 08:54:16 -07:00
apic memblock: stop using implicit alignment to SMP_CACHE_BYTES 2018-10-31 08:54:16 -07:00
cpu Merge branch 'core/urgent' into x86/urgent, to pick up objtool fix 2018-11-03 23:42:16 +01:00
fpu x86/fpu: Remove second definition of fpu in __fpu__restore_sig() 2018-10-17 12:30:31 +02:00
kprobes Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 18:43:04 +01:00
.gitignore
alternative.c Merge branch 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 17:54:58 +01:00
amd_gart_64.c dma-mapping: merge direct and noncoherent ops 2018-09-20 09:01:15 +02:00
amd_nb.c x86/pci, x86/amd_nb: Add Hygon Dhyana support to PCI and northbridge 2018-09-27 18:28:58 +02:00
apb_timer.c
aperture_64.c
apm_32.c x86/APM: Fix build warning when PROC_FS is not enabled 2018-09-15 10:16:25 +02:00
asm-offsets_32.c x86/entry/32: Load task stack from x86_tss.sp1 in SYSENTER handler 2018-07-20 01:11:36 +02:00
asm-offsets_64.c x86/paravirt: Move the pv_irq_ops under the PARAVIRT_XXL umbrella 2018-09-03 16:50:36 +02:00
asm-offsets.c Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 18:43:04 +01:00
audit_64.c
bootflag.c
check.c x86/corruption-check: Use pr_*() instead of printk() 2018-09-10 14:47:33 +02:00
cpuid.c
crash_dump_32.c
crash_dump_64.c kdump, proc/vmcore: Enable kdumping encrypted memory with SME enabled 2018-10-06 12:09:26 +02:00
crash.c
devicetree.c x86: DT: use for_each_of_cpu_node iterator 2018-09-28 14:25:58 -05:00
doublefault.c
dumpstack_32.c
dumpstack_64.c
dumpstack.c x86/process: Don't mix user/kernel regs in 64bit __show_regs() 2018-09-06 14:33:12 +02:00
e820.c memblock: stop using implicit alignment to SMP_CACHE_BYTES 2018-10-31 08:54:16 -07:00
early_printk.c x86/earlyprintk: Add a force option for pciserial device 2018-10-02 21:02:47 +02:00
early-quirks.c On GEM side: 2018-07-20 12:29:24 +10:00
ebda.c
eisa.c x86/EISA: Don't probe EISA bus for Xen PV guests 2018-09-11 23:36:50 +02:00
espfix_64.c
ftrace_32.S
ftrace_64.S
ftrace.c
head32.c x86/boot: Add ACPI RSDP address to setup_header 2018-10-10 10:44:22 +02:00
head64.c x86: Clean up 'sizeof x' => 'sizeof(x)' 2018-10-29 07:13:28 +01:00
head_32.S x86/pgtable/32: Allocate 8k page-tables when PTI is enabled 2018-07-20 01:11:41 +02:00
head_64.S Merge branch 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 17:54:58 +01:00
hpet.c x86: Don't include linux/irq.h from asm/hardirq.h 2018-08-05 09:53:13 +02:00
hw_breakpoint.c perf/arch/x86: Implement hw_breakpoint_arch_parse() 2018-06-26 09:07:55 +02:00
i8237.c
i8253.c
i8259.c x86: Don't include linux/irq.h from asm/hardirq.h 2018-08-05 09:53:13 +02:00
idt.c x86: Don't include linux/irq.h from asm/hardirq.h 2018-08-05 09:53:13 +02:00
io_delay.c
ioport.c
irq_32.c x86: Don't include linux/irq.h from asm/hardirq.h 2018-08-05 09:53:13 +02:00
irq_64.c x86: Don't include linux/irq.h from asm/hardirq.h 2018-08-05 09:53:13 +02:00
irq_work.c
irq.c x86: Don't include linux/irq.h from asm/hardirq.h 2018-08-05 09:53:13 +02:00
irqflags.S x86/paravirt: Make native_save_fl() extern inline 2018-07-03 10:56:27 +02:00
irqinit.c x86: Don't include linux/irq.h from asm/hardirq.h 2018-08-05 09:53:13 +02:00
itmt.c
jailhouse.c
jump_label.c x86/jump_label: Switch to jump_entry accessors 2018-09-27 17:56:48 +02:00
kdebugfs.c
kexec-bzimage64.c Fix kexec forbidding kernels signed with keys in the secondary keyring to boot 2018-08-16 09:57:20 -07:00
kgdb.c
ksysfs.c treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
kvm.c x86/paravirt: Use a single ops structure 2018-09-03 16:50:35 +02:00
kvmclock.c Merge branch 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 17:54:58 +01:00
ldt.c x86/mm/tlb: Add freed_tables argument to flush_tlb_mm_range 2018-10-09 16:51:12 +02:00
livepatch.c
machine_kexec_32.c x86/kexec: Allocate 8k PGDs for PTI 2018-07-30 13:53:48 +02:00
machine_kexec_64.c
macros.S x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs 2018-10-06 15:52:17 +02:00
Makefile x86/paravirt: Make native_save_fl() extern inline 2018-07-03 10:56:27 +02:00
mmconf-fam10h_64.c
module.c x86: Add support for 64-bit place relative relocations 2018-09-27 17:56:47 +02:00
mpparse.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
msr.c x86: Clean up 'sizeof x' => 'sizeof(x)' 2018-10-29 07:13:28 +01:00
nmi_selftest.c
nmi.c
paravirt_patch_32.c x86/paravirt: Remove unused _paravirt_ident_32 2018-10-30 09:55:31 +01:00
paravirt_patch_64.c x86/paravirt: Remove unused _paravirt_ident_32 2018-10-30 09:55:31 +01:00
paravirt-spinlocks.c x86/paravirt: Use a single ops structure 2018-09-03 16:50:35 +02:00
paravirt.c x86/paravirt: Remove unused _paravirt_ident_32 2018-10-30 09:55:31 +01:00
pci-calgary_64.c
pci-dma.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
pci-iommu_table.c x86/iommu: Use NULL instead of 0 2018-08-02 14:33:19 +02:00
pci-swiotlb.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
pcspeaker.c x86/platform/pcspeaker: Use PTR_ERR_OR_ZERO() to fix ptr_ret.cocci warning 2018-07-24 09:46:42 +02:00
perf_regs.c perf/x86: Store user space frame-pointer value on a sample 2018-05-25 08:11:12 +02:00
platform-quirks.c
pmem.c
probe_roms.c
process_32.c x86/process: Don't mix user/kernel regs in 64bit __show_regs() 2018-09-06 14:33:12 +02:00
process_64.c x86/compat: Adjust in_compat_syscall() to generic code under !COMPAT 2018-11-01 12:59:25 +01:00
process.c x86/entry/32: Enter the kernel via trampoline stack 2018-07-20 01:11:37 +02:00
ptrace.c Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2018-10-24 11:22:39 +01:00
pvclock.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
quirks.c x86/mce: Check for alternate indication of machine check recovery on Skylake 2018-06-07 22:22:12 +02:00
reboot_fixups_32.c
reboot.c
relocate_kernel_32.S
relocate_kernel_64.S
resource.c
rtc.c
setup_percpu.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
setup.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
signal_compat.c
signal.c rseq: Avoid infinite recursion when delivering SIGSEGV 2018-06-22 19:04:22 +02:00
smp.c x86/irq: Let interrupt handlers set kvm_cpu_l1tf_flush_l1d 2018-08-05 09:53:13 +02:00
smpboot.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
stacktrace.c x86/stacktrace: Do not fail for ORC with regs on stack 2018-06-21 16:34:56 +02:00
step.c
sys_x86_64.c x86/compat: Adjust in_compat_syscall() to generic code under !COMPAT 2018-11-01 12:59:25 +01:00
sysfb_efi.c
sysfb_simplefb.c
sysfb.c
tboot.c
tce_64.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
time.c Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 19:07:25 +01:00
tls.c
tls.h
topology.c x86/xen: Disable CPU0 hotplug for Xen PV 2018-09-12 21:15:02 +02:00
trace_clock.c
tracepoint.c
traps.c x86/traps: Use format string with panic() call 2018-10-29 07:19:26 +01:00
tsc_msr.c x86/cpu: Sanitize FAM6_ATOM naming 2018-10-02 10:14:32 +02:00
tsc_sync.c
tsc.c x86/tsc: Make calibration refinement more robust 2018-11-06 21:53:15 +01:00
umip.c signal/x86: Use force_sig_fault where appropriate 2018-09-21 15:30:54 +02:00
unwind_frame.c
unwind_guess.c
unwind_orc.c x86/unwind/orc: Detect the end of the stack 2018-06-21 16:34:56 +02:00
uprobes.c signal: Properly deliver SIGSEGV from x86 uprobes 2018-09-11 21:18:53 +02:00
verify_cpu.S
vm86_32.c x86/mm/tlb: Add freed_tables argument to flush_tlb_mm_range 2018-10-09 16:51:12 +02:00
vmlinux.lds.S Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 18:43:04 +01:00
vsmp_64.c x86/paravirt: Move the pv_irq_ops under the PARAVIRT_XXL umbrella 2018-09-03 16:50:36 +02:00
x86_init.c x86/acpi, x86/boot: Take RSDP address for boot params if available 2018-10-10 10:44:22 +02:00