[PATCH V2] riscv: export cpu/freq invariant to scheduler

[PATCH V2] riscv: export cpu/freq invariant to scheduler

[Song Shuai]

RISC-V now manages CPU topology using arch_topology which provides
CPU capacity and frequency related interfaces to access the cpu/freq
invariant in possible heterogeneous or DVFS-enabled platforms.

Here adds topology.h file to export the arch_topology interfaces for
replacing the scheduler's constant-based cpu/freq invariant accounting.

Signed-off-by: Song Shuai <suagrfillet@gmail.com>
---
changes from V1:
  - fix the leading underscore and tidy the patch up 
---
 arch/riscv/include/asm/topology.h | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)
 create mode 100644 arch/riscv/include/asm/topology.h

diff --git a/arch/riscv/include/asm/topology.h b/arch/riscv/include/asm/topology.h
new file mode 100644
index 000000000000..727e8d163a3b
--- /dev/null
+++ b/arch/riscv/include/asm/topology.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_RISCV_TOPOLOGY_H
+#define _ASM_RISCV_TOPOLOGY_H
+
+#include <linux/arch_topology.h>
+
+/* Replace task scheduler's default frequency-invariant accounting */
+#define arch_scale_freq_tick	topology_scale_freq_tick
+#define arch_set_freq_scale	topology_set_freq_scale
+#define arch_scale_freq_capacity	topology_get_freq_scale
+#define arch_scale_freq_invariant	topology_scale_freq_invariant
+
+/* Replace task scheduler's default cpu-invariant accounting */
+#define arch_scale_cpu_capacity	topology_get_cpu_scale
+
+/* Enable topology flag updates */
+#define arch_update_cpu_topology	topology_update_cpu_topology
+
+#include <asm-generic/topology.h>
+#endif /* _ASM_RISCV_TOPOLOGY_H */
-- 
2.20.1

Re: [PATCH V2] riscv: export cpu/freq invariant to scheduler

[Andrew Jones]

On Thu, Mar 23, 2023 at 08:39:24PM +0800, Song Shuai wrote:
> RISC-V now manages CPU topology using arch_topology which provides
> CPU capacity and frequency related interfaces to access the cpu/freq
> invariant in possible heterogeneous or DVFS-enabled platforms.
> 
> Here adds topology.h file to export the arch_topology interfaces for
> replacing the scheduler's constant-based cpu/freq invariant accounting.
> 
> Signed-off-by: Song Shuai <suagrfillet@gmail.com>
> ---
> changes from V1:
>   - fix the leading underscore and tidy the patch up 
> ---
>  arch/riscv/include/asm/topology.h | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
>  create mode 100644 arch/riscv/include/asm/topology.h
> 
> diff --git a/arch/riscv/include/asm/topology.h b/arch/riscv/include/asm/topology.h
> new file mode 100644
> index 000000000000..727e8d163a3b
> --- /dev/null
> +++ b/arch/riscv/include/asm/topology.h
> @@ -0,0 +1,20 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef _ASM_RISCV_TOPOLOGY_H
> +#define _ASM_RISCV_TOPOLOGY_H
> +
> +#include <linux/arch_topology.h>
> +
> +/* Replace task scheduler's default frequency-invariant accounting */
> +#define arch_scale_freq_tick	topology_scale_freq_tick
> +#define arch_set_freq_scale	topology_set_freq_scale

I was thinking all the right hand side would line up, which means
the above two need additional tabs and so does topology_get_cpu_scale.

> +#define arch_scale_freq_capacity	topology_get_freq_scale
> +#define arch_scale_freq_invariant	topology_scale_freq_invariant
> +
> +/* Replace task scheduler's default cpu-invariant accounting */
> +#define arch_scale_cpu_capacity	topology_get_cpu_scale
> +
> +/* Enable topology flag updates */
> +#define arch_update_cpu_topology	topology_update_cpu_topology
> +
> +#include <asm-generic/topology.h>

I'd also prefer a blank line here.

> +#endif /* _ASM_RISCV_TOPOLOGY_H */
> -- 
> 2.20.1
>

Otherwise,

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

Thanks,
drew

Re: [PATCH V2] riscv: export cpu/freq invariant to scheduler

[Ley Foon Tan]

On Fri, Mar 24, 2023 at 1:52 AM Andrew Jones <ajones@ventanamicro.com> wrote:
>
> On Thu, Mar 23, 2023 at 08:39:24PM +0800, Song Shuai wrote:
> > RISC-V now manages CPU topology using arch_topology which provides
> > CPU capacity and frequency related interfaces to access the cpu/freq
> > invariant in possible heterogeneous or DVFS-enabled platforms.
> >
> > Here adds topology.h file to export the arch_topology interfaces for
> > replacing the scheduler's constant-based cpu/freq invariant accounting.
> >
> > Signed-off-by: Song Shuai <suagrfillet@gmail.com>
Thanks for submitting this.

Reviewed-by: Ley Foon Tan <lftan@kernel.org>

Regards
Ley Foon

Re: [PATCH V2] riscv: export cpu/freq invariant to scheduler

[Palmer Dabbelt]

On Thu, 23 Mar 2023 10:24:03 PDT (-0700), ajones@ventanamicro.com wrote:
> On Thu, Mar 23, 2023 at 08:39:24PM +0800, Song Shuai wrote:
>> RISC-V now manages CPU topology using arch_topology which provides
>> CPU capacity and frequency related interfaces to access the cpu/freq
>> invariant in possible heterogeneous or DVFS-enabled platforms.
>>
>> Here adds topology.h file to export the arch_topology interfaces for
>> replacing the scheduler's constant-based cpu/freq invariant accounting.
>>
>> Signed-off-by: Song Shuai <suagrfillet@gmail.com>
>> ---
>> changes from V1:
>>   - fix the leading underscore and tidy the patch up
>> ---
>>  arch/riscv/include/asm/topology.h | 20 ++++++++++++++++++++
>>  1 file changed, 20 insertions(+)
>>  create mode 100644 arch/riscv/include/asm/topology.h
>>
>> diff --git a/arch/riscv/include/asm/topology.h b/arch/riscv/include/asm/topology.h
>> new file mode 100644
>> index 000000000000..727e8d163a3b
>> --- /dev/null
>> +++ b/arch/riscv/include/asm/topology.h
>> @@ -0,0 +1,20 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +#ifndef _ASM_RISCV_TOPOLOGY_H
>> +#define _ASM_RISCV_TOPOLOGY_H
>> +
>> +#include <linux/arch_topology.h>
>> +
>> +/* Replace task scheduler's default frequency-invariant accounting */
>> +#define arch_scale_freq_tick	topology_scale_freq_tick
>> +#define arch_set_freq_scale	topology_set_freq_scale
>
> I was thinking all the right hand side would line up, which means
> the above two need additional tabs and so does topology_get_cpu_scale.

I don't see a respin, but given that the feedback in just whitespace 
changes I've got and picked this up while fixing the whitespace.

>
>> +#define arch_scale_freq_capacity	topology_get_freq_scale
>> +#define arch_scale_freq_invariant	topology_scale_freq_invariant
>> +
>> +/* Replace task scheduler's default cpu-invariant accounting */
>> +#define arch_scale_cpu_capacity	topology_get_cpu_scale
>> +
>> +/* Enable topology flag updates */
>> +#define arch_update_cpu_topology	topology_update_cpu_topology
>> +
>> +#include <asm-generic/topology.h>
>
> I'd also prefer a blank line here.
>
>> +#endif /* _ASM_RISCV_TOPOLOGY_H */
>> --
>> 2.20.1
>>
>
> Otherwise,
>
> Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
>
> Thanks,
> drew

Re: [PATCH V2] riscv: export cpu/freq invariant to scheduler

[Conor Dooley]

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+CC Bjorn,

On Thu, Mar 23, 2023 at 08:39:24PM +0800, Song Shuai wrote:
> RISC-V now manages CPU topology using arch_topology which provides
> CPU capacity and frequency related interfaces to access the cpu/freq
> invariant in possible heterogeneous or DVFS-enabled platforms.
> 
> Here adds topology.h file to export the arch_topology interfaces for
> replacing the scheduler's constant-based cpu/freq invariant accounting.
> 
> Signed-off-by: Song Shuai <suagrfillet@gmail.com>

Something in CI really, really doesn't like this patch:
https://patchwork.kernel.org/project/linux-riscv/patch/20230323123924.3032174-1-suagrfillet@gmail.com/

The CI stuff applies the patch, builds the tree, resets to HEAD~1,
builds it again, goes back to the applied patch and builds a third time.
Builds 2 and 3 are incremental.
In theory the same stuff should change between applying and removing the
patch, and therefore each of builds 2 and 3 should have the same coverage,
but that doesn't seem to be happening here.
Build 2 looks to have rebuilt almost nothing and build 3 has rebuilt the
world.
I'm gonna chalk that one down as a CI issue rather than your patch!

That said, I was wondering if you would end up submitting this patch,
given the discussion on your last one ;)

Looks to be the same as was done for arm64, so fwiw:
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>

Thanks,
Conor.

> ---
> changes from V1:
>   - fix the leading underscore and tidy the patch up 
> ---
>  arch/riscv/include/asm/topology.h | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
>  create mode 100644 arch/riscv/include/asm/topology.h
> 
> diff --git a/arch/riscv/include/asm/topology.h b/arch/riscv/include/asm/topology.h
> new file mode 100644
> index 000000000000..727e8d163a3b
> --- /dev/null
> +++ b/arch/riscv/include/asm/topology.h
> @@ -0,0 +1,20 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef _ASM_RISCV_TOPOLOGY_H
> +#define _ASM_RISCV_TOPOLOGY_H
> +
> +#include <linux/arch_topology.h>
> +
> +/* Replace task scheduler's default frequency-invariant accounting */
> +#define arch_scale_freq_tick	topology_scale_freq_tick
> +#define arch_set_freq_scale	topology_set_freq_scale
> +#define arch_scale_freq_capacity	topology_get_freq_scale
> +#define arch_scale_freq_invariant	topology_scale_freq_invariant
> +
> +/* Replace task scheduler's default cpu-invariant accounting */
> +#define arch_scale_cpu_capacity	topology_get_cpu_scale
> +
> +/* Enable topology flag updates */
> +#define arch_update_cpu_topology	topology_update_cpu_topology
> +
> +#include <asm-generic/topology.h>
> +#endif /* _ASM_RISCV_TOPOLOGY_H */
> -- 
> 2.20.1
> 
> 

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Re: [PATCH V2] riscv: export cpu/freq invariant to scheduler

[Palmer Dabbelt]

On Thu, 23 Mar 2023 20:39:24 +0800, Song Shuai wrote:
> RISC-V now manages CPU topology using arch_topology which provides
> CPU capacity and frequency related interfaces to access the cpu/freq
> invariant in possible heterogeneous or DVFS-enabled platforms.
> 
> Here adds topology.h file to export the arch_topology interfaces for
> replacing the scheduler's constant-based cpu/freq invariant accounting.
> 
> [...]

Applied, thanks!

[1/1] riscv: export cpu/freq invariant to scheduler
      https://git.kernel.org/palmer/c/c4b52d8b6c1d

Best regards,
-- 
Palmer Dabbelt <palmer@rivosinc.com>

Re: [PATCH V2] riscv: export cpu/freq invariant to scheduler

[patchwork-bot+linux-riscv]

Hello:

This patch was applied to riscv/linux.git (for-next)
by Palmer Dabbelt <palmer@rivosinc.com>:

On Thu, 23 Mar 2023 20:39:24 +0800 you wrote:
> RISC-V now manages CPU topology using arch_topology which provides
> CPU capacity and frequency related interfaces to access the cpu/freq
> invariant in possible heterogeneous or DVFS-enabled platforms.
> 
> Here adds topology.h file to export the arch_topology interfaces for
> replacing the scheduler's constant-based cpu/freq invariant accounting.
> 
> [...]

Here is the summary with links:
  - [V2] riscv: export cpu/freq invariant to scheduler
    https://git.kernel.org/riscv/c/c4b52d8b6c1d

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html