diff options
| author | Wanpeng Li <wanpeng.li@hotmail.com> | 2017-04-11 02:49:21 -0700 |
|---|---|---|
| committer | Radim Krčmář <rkrcmar@redhat.com> | 2017-04-12 20:17:38 +0200 |
| commit | 5a48a622718cbd2d26d449f38ba40a2b5f7212cf (patch) | |
| tree | 990d9f540cef822b9fba710169d8a9a6cf035747 /arch | |
| parent | bd8fab39cd4fe429f161dfc86bf64993d5c17320 (diff) | |
| download | linux-5a48a622718cbd2d26d449f38ba40a2b5f7212cf.tar.bz2 | |
x86/kvm: virt_xxx memory barriers instead of mandatory barriers
virt_xxx memory barriers are implemented trivially using the low-level
__smp_xxx macros, __smp_xxx is equal to a compiler barrier for strong
TSO memory model, however, mandatory barriers will unconditional add
memory barriers, this patch replaces the rmb() in kvm_steal_clock() by
virt_rmb().
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/kvm.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 14f65a5f938e..da5c09789984 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -396,9 +396,9 @@ static u64 kvm_steal_clock(int cpu) src = &per_cpu(steal_time, cpu); do { version = src->version; - rmb(); + virt_rmb(); steal = src->steal; - rmb(); + virt_rmb(); } while ((version & 1) || (version != src->version)); return steal; |