On 04/06/2017 10:20 PM, Radim Krčmář wrote: > Users were expected to use kvm_check_request() for testing and clearing, > but request have expanded their use since then and some users want to > only test or do a faster clear. > > Make sure that requests are not directly accessed with bit operations, because > we'll be clearing them later. > > Signed-off-by: Radim Krčmář <[email protected]>
Patch itself looks sane Reviewed-by: Christian Borntraeger <[email protected]> one question: > static inline bool kvm_check_request(int req, struct kvm_vcpu *vcpu) > { > - if (test_bit(req, &vcpu->requests)) { > - clear_bit(req, &vcpu->requests); > + if (kvm_test_request(req, vcpu)) { > + kvm_clear_request(req, vcpu); This looks fine. I am just asking myself why we do not use test_and_clear_bit? Do we expect gcc to merge all test bits as a fast path? This does not seem to work as far as I can tell and almost everybody does a fast path like in arch/s390/kvm/kvm-s390.c: if (!vcpu->requests) return 0; arch/x86/kvm/x86.c: if (vcpu->requests) { > > /* > * Ensure the rest of the request is visible to > kvm_check_request's >
