Hi, Xuerui, On Wed, Feb 14, 2024 at 6:16 PM WANG Xuerui <kernel@xxxxxxxxxx> wrote: > > From: WANG Xuerui <git@xxxxxxxxxx> > > All the checks currently done in kvm_check_cpucfg can be realized with > early returns, so just do that to avoid extra cognitive burden related > to the return value handling. > > The default branch is unreachable because of the earlier validation by > _kvm_get_cpucfg_mask, so mark it as such too to make things clearer. > > Signed-off-by: WANG Xuerui <git@xxxxxxxxxx> > --- > arch/loongarch/kvm/vcpu.c | 23 +++++++++++------------ > 1 file changed, 11 insertions(+), 12 deletions(-) > > diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c > index e973500611b4..9e108ffaba30 100644 > --- a/arch/loongarch/kvm/vcpu.c > +++ b/arch/loongarch/kvm/vcpu.c > @@ -339,24 +339,23 @@ static int kvm_check_cpucfg(int id, u64 val) > /* CPUCFG2 features checking */ > if (val & ~mask) > /* The unsupported features should not be set */ > - ret = -EINVAL; > - else if (!(val & CPUCFG2_LLFTP)) > + return -EINVAL; > + if (!(val & CPUCFG2_LLFTP)) > /* The LLFTP must be set, as guest must has a constant timer */ > - ret = -EINVAL; > - else if ((val & CPUCFG2_FP) && (!(val & CPUCFG2_FPSP) || !(val & CPUCFG2_FPDP))) > + return -EINVAL; > + if ((val & CPUCFG2_FP) && (!(val & CPUCFG2_FPSP) || !(val & CPUCFG2_FPDP))) > /* Single and double float point must both be set when enable FP */ > - ret = -EINVAL; > - else if ((val & CPUCFG2_LSX) && !(val & CPUCFG2_FP)) > + return -EINVAL; > + if ((val & CPUCFG2_LSX) && !(val & CPUCFG2_FP)) > /* FP should be set when enable LSX */ > - ret = -EINVAL; > - else if ((val & CPUCFG2_LASX) && !(val & CPUCFG2_LSX)) > + return -EINVAL; > + if ((val & CPUCFG2_LASX) && !(val & CPUCFG2_LSX)) > /* LSX, FP should be set when enable LASX, and FP has been checked before. */ > - ret = -EINVAL; > - break; > + return -EINVAL; > + return 0; > default: > - break; > + unreachable(); Maybe BUG() is better than unreachable()? Huacai > } > - return ret; > } > > static int kvm_get_one_reg(struct kvm_vcpu *vcpu, > -- > 2.43.0 >
