On Mon, Jan 17, 2022 at 01:37:22PM +0800, Li RongQing wrote: > After support paravirtualized TLB shootdowns, steal_time.preempted > includes not only KVM_VCPU_PREEMPTED, but also KVM_VCPU_FLUSH_TLB > > and kvm_vcpu_is_preempted should test only with KVM_VCPU_PREEMPTED This still fails to actually explain what the problem is, why did you write this patch? > > Co-developed-by: Sean Christopherson <seanjc@xxxxxxxxxx> > Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx> > Signed-off-by: Li RongQing <lirongqing@xxxxxxxxx> > --- > diff with v2: using andl and setnz > diff with v1: clear 64bit rax > > arch/x86/kernel/kvm.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c > index b061d17..fe0aead 100644 > --- a/arch/x86/kernel/kvm.c > +++ b/arch/x86/kernel/kvm.c > @@ -1025,8 +1025,9 @@ asm( > ".type __raw_callee_save___kvm_vcpu_is_preempted, @function;" > "__raw_callee_save___kvm_vcpu_is_preempted:" > "movq __per_cpu_offset(,%rdi,8), %rax;" > -"cmpb $0, " __stringify(KVM_STEAL_TIME_preempted) "+steal_time(%rax);" > -"setne %al;" > +"movb " __stringify(KVM_STEAL_TIME_preempted) "+steal_time(%rax), %al;" > +"andl $" __stringify(KVM_VCPU_PREEMPTED) ", %eax;" > +"setnz %al;" Isn't the below the simpler way of writing that same? diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index a438217cbfac..bc79adcf59ff 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -1025,7 +1025,7 @@ asm( ".type __raw_callee_save___kvm_vcpu_is_preempted, @function;" "__raw_callee_save___kvm_vcpu_is_preempted:" "movq __per_cpu_offset(,%rdi,8), %rax;" -"cmpb $0, " __stringify(KVM_STEAL_TIME_preempted) "+steal_time(%rax);" +"testb $" __stringify(KVM_VCPU_PREEMPTED) ", " __stringify(KVM_STEAL_TIME_preempted) "+steal_time(%rax);" "setne %al;" "ret;" ".size __raw_callee_save___kvm_vcpu_is_preempted, .-__raw_callee_save___kvm_vcpu_is_preempted;"
