2022-11-04 06:28:59

by Usama Arif

Subject: [PATCH] arm64: paravirt: remove conduit check in has_pv_steal_clock

arm_smccc_1_1_invoke() which is called later on in the function
will return failure if there's no conduit (or pre-SMCCC 1.1),
hence the check is unnecessary.

Suggested-by: Steven Price <[email protected]>
Signed-off-by: Usama Arif <[email protected]>
---
arch/arm64/kernel/paravirt.c | 4 ----
1 file changed, 4 deletions(-)

diff --git a/arch/arm64/kernel/paravirt.c b/arch/arm64/kernel/paravirt.c
index 57c7c211f8c7..aa718d6a9274 100644
--- a/arch/arm64/kernel/paravirt.c
+++ b/arch/arm64/kernel/paravirt.c
@@ -141,10 +141,6 @@ static bool __init has_pv_steal_clock(void)
{
struct arm_smccc_res res;

- /* To detect the presence of PV time support we require SMCCC 1.1+ */
- if (arm_smccc_1_1_get_conduit() == SMCCC_CONDUIT_NONE)
- return false;
-
arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
ARM_SMCCC_HV_PV_TIME_FEATURES, &res);

--
2.25.1

2022-11-04 09:44:33

by Steven Price

Subject: Re: [PATCH] arm64: paravirt: remove conduit check in has_pv_steal_clock

On 04/11/2022 06:16, Usama Arif wrote:
> arm_smccc_1_1_invoke() which is called later on in the function
> will return failure if there's no conduit (or pre-SMCCC 1.1),
> hence the check is unnecessary.
>
> Suggested-by: Steven Price <[email protected]>
> Signed-off-by: Usama Arif <[email protected]>

Reviewed-by: Steven Price <[email protected]>

> ---
> arch/arm64/kernel/paravirt.c | 4 ----
> 1 file changed, 4 deletions(-)
>
> diff --git a/arch/arm64/kernel/paravirt.c b/arch/arm64/kernel/paravirt.c
> index 57c7c211f8c7..aa718d6a9274 100644
> --- a/arch/arm64/kernel/paravirt.c
> +++ b/arch/arm64/kernel/paravirt.c
> @@ -141,10 +141,6 @@ static bool __init has_pv_steal_clock(void)
> {
> struct arm_smccc_res res;
>
> - /* To detect the presence of PV time support we require SMCCC 1.1+ */
> - if (arm_smccc_1_1_get_conduit() == SMCCC_CONDUIT_NONE)
> - return false;
> -
> arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
> ARM_SMCCC_HV_PV_TIME_FEATURES, &res);
>

2022-11-09 20:04:42

by Will Deacon

Subject: Re: [PATCH] arm64: paravirt: remove conduit check in has_pv_steal_clock

On Fri, 4 Nov 2022 06:16:59 +0000, Usama Arif wrote:
> arm_smccc_1_1_invoke() which is called later on in the function
> will return failure if there's no conduit (or pre-SMCCC 1.1),
> hence the check is unnecessary.
>
>

Applied to arm64 (for-next/trivial), thanks!

[1/1] arm64: paravirt: remove conduit check in has_pv_steal_clock
https://git.kernel.org/arm64/c/1e55b44d9ecd

Cheers,
--
Will

https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev