diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-01 08:40:25 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-01 08:40:25 -0700 |
commit | 5778077d03cb25aac9b6a428e18970642fc019e3 (patch) | |
tree | 2e3f3da1fb99c3646da5ed9a09644696ca5f2309 /arch/x86/kvm/x86.c | |
parent | 65a99597f044c083983f4274ab049c9ec3b9d764 (diff) | |
parent | 7e01ebffffedec22cea86ebe94802f909e4579ca (diff) |
Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm changes from Ingo Molnar:
"The biggest changes in this cycle were:
- Revamp, simplify (and in some cases fix) Time Stamp Counter (TSC)
primitives. (Andy Lutomirski)
- Add new, comprehensible entry and exit handlers written in C.
(Andy Lutomirski)
- vm86 mode cleanups and fixes. (Brian Gerst)
- 32-bit compat code cleanups. (Brian Gerst)
The amount of simplification in low level assembly code is already
palpable:
arch/x86/entry/entry_32.S | 130 +----
arch/x86/entry/entry_64.S | 197 ++-----
but more simplifications are planned.
There's also the usual laudry mix of low level changes - see the
changelog for details"
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (83 commits)
x86/asm: Drop repeated macro of X86_EFLAGS_AC definition
x86/asm/msr: Make wrmsrl() a function
x86/asm/delay: Introduce an MWAITX-based delay with a configurable timer
x86/asm: Add MONITORX/MWAITX instruction support
x86/traps: Weaken context tracking entry assertions
x86/asm/tsc: Add rdtscll() merge helper
selftests/x86: Add syscall_nt selftest
selftests/x86: Disable sigreturn_64
x86/vdso: Emit a GNU hash
x86/entry: Remove do_notify_resume(), syscall_trace_leave(), and their TIF masks
x86/entry/32: Migrate to C exit path
x86/entry/32: Remove 32-bit syscall audit optimizations
x86/vm86: Rename vm86->v86flags and v86mask
x86/vm86: Rename vm86->vm86_info to user_vm86
x86/vm86: Clean up vm86.h includes
x86/vm86: Move the vm86 IRQ definitions to vm86.h
x86/vm86: Use the normal pt_regs area for vm86
x86/vm86: Eliminate 'struct kernel_vm86_struct'
x86/vm86: Move fields from 'struct kernel_vm86_struct' to 'struct vm86'
x86/vm86: Move vm86 fields out of 'thread_struct'
...
Diffstat (limited to 'arch/x86/kvm/x86.c')
-rw-r--r-- | arch/x86/kvm/x86.c | 26 |
1 files changed, 7 insertions, 19 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 4bbc2a1676c9..1e7e76e14e89 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1441,20 +1441,8 @@ EXPORT_SYMBOL_GPL(kvm_write_tsc); static cycle_t read_tsc(void) { - cycle_t ret; - u64 last; - - /* - * Empirically, a fence (of type that depends on the CPU) - * before rdtsc is enough to ensure that rdtsc is ordered - * with respect to loads. The various CPU manuals are unclear - * as to whether rdtsc can be reordered with later loads, - * but no one has ever seen it happen. - */ - rdtsc_barrier(); - ret = (cycle_t)vget_cycles(); - - last = pvclock_gtod_data.clock.cycle_last; + cycle_t ret = (cycle_t)rdtsc_ordered(); + u64 last = pvclock_gtod_data.clock.cycle_last; if (likely(ret >= last)) return ret; @@ -1643,7 +1631,7 @@ static int kvm_guest_time_update(struct kvm_vcpu *v) return 1; } if (!use_master_clock) { - host_tsc = native_read_tsc(); + host_tsc = rdtsc(); kernel_ns = get_kernel_ns(); } @@ -2620,7 +2608,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) if (unlikely(vcpu->cpu != cpu) || check_tsc_unstable()) { s64 tsc_delta = !vcpu->arch.last_host_tsc ? 0 : - native_read_tsc() - vcpu->arch.last_host_tsc; + rdtsc() - vcpu->arch.last_host_tsc; if (tsc_delta < 0) mark_tsc_unstable("KVM discovered backwards TSC"); if (check_tsc_unstable()) { @@ -2648,7 +2636,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) { kvm_x86_ops->vcpu_put(vcpu); kvm_put_guest_fpu(vcpu); - vcpu->arch.last_host_tsc = native_read_tsc(); + vcpu->arch.last_host_tsc = rdtsc(); } static int kvm_vcpu_ioctl_get_lapic(struct kvm_vcpu *vcpu, @@ -6387,7 +6375,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) hw_breakpoint_restore(); vcpu->arch.last_guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu, - native_read_tsc()); + rdtsc()); vcpu->mode = OUTSIDE_GUEST_MODE; smp_wmb(); @@ -7196,7 +7184,7 @@ int kvm_arch_hardware_enable(void) if (ret != 0) return ret; - local_tsc = native_read_tsc(); + local_tsc = rdtsc(); stable = !check_tsc_unstable(); list_for_each_entry(kvm, &vm_list, vm_list) { kvm_for_each_vcpu(i, vcpu, kvm) { |