| Message ID | 20240713155937.45261-1-tangbin@cmss.chinamobile.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | LoongArch: KVM: Remove redundant assignment in kvm_map_page_fast | expand |
Hi Tangbin, There is only return value with -EFAULT or 0 in function kvm_map_page_fast(), if there is better error code or different error for new code, the situation will be different :) I would like to keep existing code unchanged, however thanks for your patch. Regards Bibo Mao On 2024/7/13 下午11:59, tangbin wrote: > In the function kvm_map_page_fast, the assignment of 'ret' is > redundant, so remove it. > > Signed-off-by: tangbin <tangbin@cmss.chinamobile.com> > --- > arch/loongarch/kvm/mmu.c | 17 +++++------------ > 1 file changed, 5 insertions(+), 12 deletions(-) > > diff --git a/arch/loongarch/kvm/mmu.c b/arch/loongarch/kvm/mmu.c > index 2634a9e8d..d6c922a4a 100644 > --- a/arch/loongarch/kvm/mmu.c > +++ b/arch/loongarch/kvm/mmu.c > @@ -551,7 +551,6 @@ bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) > */ > static int kvm_map_page_fast(struct kvm_vcpu *vcpu, unsigned long gpa, bool write) > { > - int ret = 0; > kvm_pfn_t pfn = 0; > kvm_pte_t *ptep, changed, new; > gfn_t gfn = gpa >> PAGE_SHIFT; > @@ -563,20 +562,16 @@ static int kvm_map_page_fast(struct kvm_vcpu *vcpu, unsigned long gpa, bool writ > > /* Fast path - just check GPA page table for an existing entry */ > ptep = kvm_populate_gpa(kvm, NULL, gpa, 0); > - if (!ptep || !kvm_pte_present(NULL, ptep)) { > - ret = -EFAULT; > + if (!ptep || !kvm_pte_present(NULL, ptep)) > goto out; > - } > > /* Track access to pages marked old */ > new = kvm_pte_mkyoung(*ptep); > /* call kvm_set_pfn_accessed() after unlock */ > > if (write && !kvm_pte_dirty(new)) { > - if (!kvm_pte_write(new)) { > - ret = -EFAULT; > + if (!kvm_pte_write(new)) > goto out; > - } > > if (kvm_pte_huge(new)) { > /* > @@ -584,10 +579,8 @@ static int kvm_map_page_fast(struct kvm_vcpu *vcpu, unsigned long gpa, bool writ > * enabled for HugePages > */ > slot = gfn_to_memslot(kvm, gfn); > - if (kvm_slot_dirty_track_enabled(slot)) { > - ret = -EFAULT; > + if (kvm_slot_dirty_track_enabled(slot)) > goto out; > - } > } > > /* Track dirtying of writeable pages */ > @@ -615,10 +608,10 @@ static int kvm_map_page_fast(struct kvm_vcpu *vcpu, unsigned long gpa, bool writ > if (page) > put_page(page); > } > - return ret; > + return 0; > out: > spin_unlock(&kvm->mmu_lock); > - return ret; > + return -EFAULT; > } > > static bool fault_supports_huge_mapping(struct kvm_memory_slot *memslot, >
diff --git a/arch/loongarch/kvm/mmu.c b/arch/loongarch/kvm/mmu.c index 2634a9e8d..d6c922a4a 100644 --- a/arch/loongarch/kvm/mmu.c +++ b/arch/loongarch/kvm/mmu.c @@ -551,7 +551,6 @@ bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) */ static int kvm_map_page_fast(struct kvm_vcpu *vcpu, unsigned long gpa, bool write) { - int ret = 0; kvm_pfn_t pfn = 0; kvm_pte_t *ptep, changed, new; gfn_t gfn = gpa >> PAGE_SHIFT; @@ -563,20 +562,16 @@ static int kvm_map_page_fast(struct kvm_vcpu *vcpu, unsigned long gpa, bool writ /* Fast path - just check GPA page table for an existing entry */ ptep = kvm_populate_gpa(kvm, NULL, gpa, 0); - if (!ptep || !kvm_pte_present(NULL, ptep)) { - ret = -EFAULT; + if (!ptep || !kvm_pte_present(NULL, ptep)) goto out; - } /* Track access to pages marked old */ new = kvm_pte_mkyoung(*ptep); /* call kvm_set_pfn_accessed() after unlock */ if (write && !kvm_pte_dirty(new)) { - if (!kvm_pte_write(new)) { - ret = -EFAULT; + if (!kvm_pte_write(new)) goto out; - } if (kvm_pte_huge(new)) { /* @@ -584,10 +579,8 @@ static int kvm_map_page_fast(struct kvm_vcpu *vcpu, unsigned long gpa, bool writ * enabled for HugePages */ slot = gfn_to_memslot(kvm, gfn); - if (kvm_slot_dirty_track_enabled(slot)) { - ret = -EFAULT; + if (kvm_slot_dirty_track_enabled(slot)) goto out; - } } /* Track dirtying of writeable pages */ @@ -615,10 +608,10 @@ static int kvm_map_page_fast(struct kvm_vcpu *vcpu, unsigned long gpa, bool writ if (page) put_page(page); } - return ret; + return 0; out: spin_unlock(&kvm->mmu_lock); - return ret; + return -EFAULT; } static bool fault_supports_huge_mapping(struct kvm_memory_slot *memslot,
In the function kvm_map_page_fast, the assignment of 'ret' is redundant, so remove it. Signed-off-by: tangbin <tangbin@cmss.chinamobile.com> --- arch/loongarch/kvm/mmu.c | 17 +++++------------ 1 file changed, 5 insertions(+), 12 deletions(-)