linux/arch/x86/kernel
Wanpeng Li 858a43aae2 KVM: X86: use paravirtualized TLB Shootdown
Remote TLB flush does a busy wait which is fine in bare-metal
scenario. But with-in the guest, the vcpus might have been pre-empted or
blocked. In this scenario, the initator vcpu would end up busy-waiting
for a long amount of time; it also consumes CPU unnecessarily to wake
up the target of the shootdown.

This patch set adds support for KVM's new paravirtualized TLB flush;
remote TLB flush does not wait for vcpus that are sleeping, instead
KVM will flush the TLB as soon as the vCPU starts running again.

The improvement is clearly visible when the host is overcommitted; in this
case, the PV TLB flush (in addition to avoiding the wait on the main CPU)
prevents preempted vCPUs from stealing precious execution time from the
running ones.

Testing on a Xeon Gold 6142 2.6GHz 2 sockets, 32 cores, 64 threads,
so 64 pCPUs, and each VM is 64 vCPUs.

ebizzy -M
              vanilla    optimized     boost
1VM            46799       48670         4%
2VM            23962       42691        78%
3VM            16152       37539       132%

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-01-16 16:34:13 +01:00
..
acpi Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-26 14:11:54 -08:00
apic x86: Fix Sparse warnings about non-static functions 2017-12-06 19:32:58 +01:00
cpu Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-12-06 17:47:29 -08:00
fpu Merge branch 'linus' into x86/asm, to pick up fixes and resolve conflicts 2017-11-07 10:53:06 +01:00
kprobes Merge branch 'linus' into perf/core, to fix conflicts 2017-11-07 10:30:18 +01:00
.gitignore
alternative.c kprobes, x86/alternatives: Use text_mutex to protect smp_alt_modules 2017-11-07 12:20:09 +01:00
amd_gart_64.c x86: remove arch specific dma_supported implementation 2017-06-28 06:54:46 -07:00
amd_nb.c x86/cpu/AMD: Apply the Erratum 688 fix when the BIOS doesn't 2017-10-22 13:06:02 +02:00
apb_timer.c
aperture_64.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
apm_32.c dmi: Mark all struct dmi_system_id instances const 2017-09-14 11:59:30 +02:00
asm-offsets_32.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
asm-offsets_64.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
asm-offsets.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
audit_64.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
bootflag.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
check.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cpuid.c
crash_dump_32.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
crash_dump_64.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
crash.c resource: Fix resource_size.cocci warnings 2017-11-07 20:44:56 +01:00
devicetree.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
doublefault.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
dumpstack_32.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
dumpstack_64.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
dumpstack.c x86/asm/32: Remove a bunch of '& 0xffff' from pt_regs segment reads 2017-07-30 12:04:41 +02:00
e820.c x86/boot/e820: Add support to determine the E820 type of an address 2017-07-18 11:38:01 +02:00
early_printk.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
early-quirks.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ebda.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
eisa.c x86/eisa: Add missing include 2017-08-31 21:34:48 +02:00
espfix_64.c kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACK 2017-11-15 18:21:04 -08:00
ftrace_32.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ftrace_64.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ftrace.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
head32.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
head64.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
head_32.S Merge branch 'linus' into x86/asm, to pick up fixes and resolve conflicts 2017-11-07 10:53:06 +01:00
head_64.S Merge branch 'linus' into x86/asm, to pick up fixes and resolve conflicts 2017-11-07 10:53:06 +01:00
hpet.c x86/hpet: Cure interface abuse in the resume path 2017-08-01 13:02:37 +02:00
hw_breakpoint.c
i8237.c
i8253.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
i8259.c Merge branch 'linus' into x86/apic, to resolve conflicts 2017-11-07 10:51:10 +01:00
idt.c Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 18:29:23 -08:00
io_delay.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ioport.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
irq_32.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
irq_64.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
irq_work.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
irq.c x86/irq: Simplify hotplug vector accounting 2017-09-25 20:52:02 +02:00
irqinit.c Merge branch 'linus' into x86/apic, to resolve conflicts 2017-11-07 10:51:10 +01:00
itmt.c
jump_label.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
kdebugfs.c x86, mpparse, x86/acpi, x86/PCI, x86/dmi, SFI: Use memremap() for RAM mappings 2017-07-18 11:37:58 +02:00
kexec-bzimage64.c x86/boot/e820: Rename the e820_table_firmware to e820_table_kexec 2017-07-05 10:09:02 +02:00
kgdb.c
ksysfs.c x86/sysfs: Fix off-by-one error in loop termination 2017-09-25 09:36:16 +02:00
kvm.c KVM: X86: use paravirtualized TLB Shootdown 2018-01-16 16:34:13 +01:00
kvmclock.c xen: features and fixes for v4.15-rc1 2017-11-16 13:06:27 -08:00
ldt.c Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 14:13:48 -08:00
livepatch.c
machine_kexec_32.c x86/idt: Consolidate IDT invalidation 2017-08-29 12:07:26 +02:00
machine_kexec_64.c x86/mm, kexec: Fix memory corruption with SME on successive kexecs 2017-07-30 12:09:12 +02:00
Makefile x86/umip: Add emulation code for UMIP instructions 2017-11-08 11:16:22 +01:00
mmconf-fam10h_64.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
module.c x86/module: Detect and skip invalid relocations 2017-11-05 09:52:16 +01:00
mpparse.c x86/boot: Fix boot failure when SMP MP-table is based at 0 2017-11-17 15:30:33 +01:00
msr.c
nmi_selftest.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
nmi.c locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE() 2017-10-25 11:01:08 +02:00
paravirt_patch_32.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
paravirt_patch_64.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
paravirt-spinlocks.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
paravirt.c locking/paravirt: Use new static key for controlling call of virt_spin_lock() 2017-10-10 11:50:12 +02:00
pci-calgary_64.c x86, calgary: Convert timers to use timer_setup() 2017-11-02 15:50:32 -07:00
pci-dma.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pci-iommu_table.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pci-nommu.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pci-swiotlb.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pcspeaker.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
perf_regs.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
platform-quirks.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pmem.c resource: Provide resource struct in resource walk callback 2017-11-07 15:35:57 +01:00
probe_roms.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
process_32.c x86/entry/64: Remove all remaining direct thread_struct::sp0 reads 2017-11-02 11:04:47 +01:00
process_64.c x86/entry/64: Remove thread_struct::sp0 2017-11-02 11:04:48 +01:00
process.c x86/tlb: Disable interrupts when changing CR4 2017-11-25 13:28:43 +01:00
ptrace.c
pvclock.c x86/pvclock: add setter for pvclock_pvti_cpu0_va 2017-11-08 16:33:14 -05:00
quirks.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
reboot_fixups_32.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
reboot.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
relocate_kernel_32.S
relocate_kernel_64.S x86/mm, kexec: Fix memory corruption with SME on successive kexecs 2017-07-30 12:09:12 +02:00
resource.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rtc.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
setup_percpu.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
setup.c Merge branch 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 19:07:38 -08:00
signal_compat.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
signal.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
smp.c x86/tracing: Disentangle pagefault and resched IPI tracing key 2017-08-29 11:42:29 +02:00
smpboot.c x86/idt: Load idt early in start_secondary 2017-11-28 08:15:40 +01:00
stacktrace.c x86/stacktrace: Avoid recording save_stack_trace() wrappers 2017-09-29 19:44:03 +02:00
step.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sys_x86_64.c x86/mm: Prevent non-MAP_FIXED mapping across DEFAULT_MAP_WINDOW border 2017-11-16 11:43:11 +01:00
sysfb_efi.c
sysfb_simplefb.c
sysfb.c
tboot.c iommu/vt-d: Correctly disable Intel IOMMU force on 2017-06-15 16:41:10 +02:00
tce_64.c
time.c Merge branch 'linus' into x86/apic, to resolve conflicts 2017-11-07 10:51:10 +01:00
tls.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
tls.h
topology.c
trace_clock.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
tracepoint.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
traps.c kmemcheck: remove annotations 2017-11-15 18:21:04 -08:00
tsc_msr.c
tsc_sync.c Merge branch 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 19:07:38 -08:00
tsc.c Merge branch 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 19:07:38 -08:00
umip.c x86/umip: Fix insn_get_code_seg_params()'s return value 2017-11-23 20:17:59 +01:00
unwind_frame.c x86/unwind: Disable unwinder warnings on 32-bit 2017-10-10 12:49:49 +02:00
unwind_guess.c x86/unwind: Add the ORC unwinder 2017-07-26 13:18:20 +02:00
unwind_orc.c x86/unwind: Disable KASAN checking in the ORC unwinder 2017-11-08 10:21:49 +01:00
uprobes.c uprobes/x86: Use existing definitions for segment override prefixes 2017-11-01 21:50:08 +01:00
verify_cpu.S x86/boot: Annotate verify_cpu() as a callable function 2017-09-28 09:39:03 +02:00
vm86_32.c Merge branch 'linus' into x86/asm, to pick up fixes and resolve conflicts 2017-11-07 10:53:06 +01:00
vmlinux.lds.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
vsmp_64.c x86/apic: Remove unused callbacks 2017-09-25 20:51:58 +02:00
x86_init.c Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 18:29:23 -08:00