2010-01-14 17:01:53

by Roel Kluin

Subject: [PATCH] KVM: remove redundant NULL tests

kvm_get_exit_data() cannot return a NULL pointer.

Signed-off-by: Roel Kluin <[email protected]>
---
arch/ia64/kvm/kvm_fw.c | 28 +++++++++++++---------------
1 files changed, 13 insertions(+), 15 deletions(-)

diff --git a/arch/ia64/kvm/kvm_fw.c b/arch/ia64/kvm/kvm_fw.c
index e4b8231..cb548ee 100644
--- a/arch/ia64/kvm/kvm_fw.c
+++ b/arch/ia64/kvm/kvm_fw.c
@@ -75,7 +75,7 @@ static void set_pal_result(struct kvm_vcpu *vcpu,
struct exit_ctl_data *p;

p = kvm_get_exit_data(vcpu);
- if (p && p->exit_reason == EXIT_REASON_PAL_CALL) {
+ if (p->exit_reason == EXIT_REASON_PAL_CALL) {
p->u.pal_data.ret = result;
return ;
}
@@ -87,7 +87,7 @@ static void set_sal_result(struct kvm_vcpu *vcpu,
struct exit_ctl_data *p;

p = kvm_get_exit_data(vcpu);
- if (p && p->exit_reason == EXIT_REASON_SAL_CALL) {
+ if (p->exit_reason == EXIT_REASON_SAL_CALL) {
p->u.sal_data.ret = result;
return ;
}
@@ -322,7 +322,7 @@ static u64 kvm_get_pal_call_index(struct kvm_vcpu *vcpu)
struct exit_ctl_data *p;

p = kvm_get_exit_data(vcpu);
- if (p && (p->exit_reason == EXIT_REASON_PAL_CALL))
+ if (p->exit_reason == EXIT_REASON_PAL_CALL)
index = p->u.pal_data.gr28;

return index;
@@ -646,18 +646,16 @@ static void kvm_get_sal_call_data(struct kvm_vcpu *vcpu, u64 *in0, u64 *in1,

p = kvm_get_exit_data(vcpu);

- if (p) {
- if (p->exit_reason == EXIT_REASON_SAL_CALL) {
- *in0 = p->u.sal_data.in0;
- *in1 = p->u.sal_data.in1;
- *in2 = p->u.sal_data.in2;
- *in3 = p->u.sal_data.in3;
- *in4 = p->u.sal_data.in4;
- *in5 = p->u.sal_data.in5;
- *in6 = p->u.sal_data.in6;
- *in7 = p->u.sal_data.in7;
- return ;
- }
+ if (p->exit_reason == EXIT_REASON_SAL_CALL) {
+ *in0 = p->u.sal_data.in0;
+ *in1 = p->u.sal_data.in1;
+ *in2 = p->u.sal_data.in2;
+ *in3 = p->u.sal_data.in3;
+ *in4 = p->u.sal_data.in4;
+ *in5 = p->u.sal_data.in5;
+ *in6 = p->u.sal_data.in6;
+ *in7 = p->u.sal_data.in7;
+ return ;
}
*in0 = 0;
}

2010-01-17 03:20:10

by Zhang, Xiantao

Subject: RE: [PATCH] KVM: remove redundant NULL tests

Bill Davidsen wrote:
> Roel Kluin wrote:
>> kvm_get_exit_data() cannot return a NULL pointer.
>>
>> Signed-off-by: Roel Kluin <[email protected]>
>> ---
>> arch/ia64/kvm/kvm_fw.c | 28 +++++++++++++---------------
>> 1 files changed, 13 insertions(+), 15 deletions(-)
>>
>> diff --git a/arch/ia64/kvm/kvm_fw.c b/arch/ia64/kvm/kvm_fw.c
>> index e4b8231..cb548ee 100644
>> --- a/arch/ia64/kvm/kvm_fw.c
>> +++ b/arch/ia64/kvm/kvm_fw.c
>> @@ -75,7 +75,7 @@ static void set_pal_result(struct kvm_vcpu *vcpu,
>> struct exit_ctl_data *p;
>>
>> p = kvm_get_exit_data(vcpu);
>> - if (p && p->exit_reason == EXIT_REASON_PAL_CALL) {
>> + if (p->exit_reason == EXIT_REASON_PAL_CALL) {
>> p->u.pal_data.ret = result;
>> return ;
>> }
> [___etc___]
>
> Clearly the original author thought that there was a path where
> kvm_exit_data could return a NULL pointer, was that ever possible?

Originally, we planed to allocate the exit_data dynamically, but considering some constrains, the exit_data is allocated statically, so the check for NULL is useless now.
Xiantao-

2010-01-17 12:26:33

by Avi Kivity

Subject: Re: [PATCH] KVM: remove redundant NULL tests

On 01/14/2010 07:05 PM, Roel Kluin wrote:
> kvm_get_exit_data() cannot return a NULL pointer.
>

Applied, thanks.

--
error compiling committee.c: too many arguments to function

2010-01-16 18:29:36

by Bill Davidsen

Subject: Re: [PATCH] KVM: remove redundant NULL tests

Roel Kluin wrote:
> kvm_get_exit_data() cannot return a NULL pointer.
>
> Signed-off-by: Roel Kluin <[email protected]>
> ---
> arch/ia64/kvm/kvm_fw.c | 28 +++++++++++++---------------
> 1 files changed, 13 insertions(+), 15 deletions(-)
>
> diff --git a/arch/ia64/kvm/kvm_fw.c b/arch/ia64/kvm/kvm_fw.c
> index e4b8231..cb548ee 100644
> --- a/arch/ia64/kvm/kvm_fw.c
> +++ b/arch/ia64/kvm/kvm_fw.c
> @@ -75,7 +75,7 @@ static void set_pal_result(struct kvm_vcpu *vcpu,
> struct exit_ctl_data *p;
>
> p = kvm_get_exit_data(vcpu);
> - if (p && p->exit_reason == EXIT_REASON_PAL_CALL) {
> + if (p->exit_reason == EXIT_REASON_PAL_CALL) {
> p->u.pal_data.ret = result;
> return ;
> }
[___etc___]

Clearly the original author thought that there was a path where kvm_exit_data
could return a NULL pointer, was that ever possible?

--
Bill Davidsen <[email protected]>
"We have more to fear from the bungling of the incompetent than from
the machinations of the wicked." - from Slashdot