Re: [PATCH -next] KVM: x86: remove set but not used variable 'called'

From: maowenan
Date: Tue Nov 19 2019 - 07:42:47 EST




å 2019/11/19 19:58, Vitaly Kuznetsov åé:
> Mao Wenan <maowenan@xxxxxxxxxx> writes:
>
>> Fixes gcc '-Wunused-but-set-variable' warning:
>>
>> arch/x86/kvm/x86.c: In function kvm_make_scan_ioapic_request_mask:
>> arch/x86/kvm/x86.c:7911:7: warning: variable called set but not
>> used [-Wunused-but-set-variable]
>>
>> It is not used since commit 7ee30bc132c6 ("KVM: x86: deliver KVM
>> IOAPIC scan request to target vCPUs")
>
> Better expressed as
>
> Fixes: 7ee30bc132c6 ("KVM: x86: deliver KVM IOAPIC scan request to target vCPUs")

This is just a cleanup, so Fixes tag is no need.
>
>>
>> Signed-off-by: Mao Wenan <maowenan@xxxxxxxxxx>
>> ---
>> arch/x86/kvm/x86.c | 5 ++---
>> 1 file changed, 2 insertions(+), 3 deletions(-)
>>
>> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
>> index 0d0a682..870f0bc 100644
>> --- a/arch/x86/kvm/x86.c
>> +++ b/arch/x86/kvm/x86.c
>> @@ -7908,12 +7908,11 @@ void kvm_make_scan_ioapic_request_mask(struct kvm *kvm,
>> unsigned long *vcpu_bitmap)
>> {
>> cpumask_var_t cpus;
>> - bool called;
>>
>> zalloc_cpumask_var(&cpus, GFP_ATOMIC);
>>
>> - called = kvm_make_vcpus_request_mask(kvm, KVM_REQ_SCAN_IOAPIC,
>> - vcpu_bitmap, cpus);
>> + kvm_make_vcpus_request_mask(kvm, KVM_REQ_SCAN_IOAPIC,
>> + vcpu_bitmap, cpus);
>
> IMHO as kvm_make_vcpus_request_mask() returns value it would probably
> make sense to explicitly show that we're not interested in the result,
>
> (void)kvm_make_vcpus_request_mask()

thanks, but I think is no need to add (void) before kvm_make_vcpus_request_mask()
because we are not interested in it's return value.

>
>>
>> free_cpumask_var(cpus);
>> }
>