We could bail out early when psi was disabled.

Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>
---
 kernel/sched/psi.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c
index 81fca77397f6..e74e14762d49 100644
--- a/kernel/sched/psi.c
+++ b/kernel/sched/psi.c
@@ -1005,6 +1005,9 @@ void psi_account_irqtime(struct task_struct *task, u32 delta)
 	struct psi_group_cpu *groupc;
 	u64 now;
 
+	if (static_branch_likely(&psi_disabled))
+		return;
+
 	if (!task->pid)
 		return;
 
-- 
2.25.1

On 2023/9/25 18:21, Haifeng Xu wrote:
> We could bail out early when psi was disabled.
> 
> Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>
> ---
>  kernel/sched/psi.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c
> index 81fca77397f6..e74e14762d49 100644
> --- a/kernel/sched/psi.c
> +++ b/kernel/sched/psi.c
> @@ -1005,6 +1005,9 @@ void psi_account_irqtime(struct task_struct *task, u32 delta)
>  	struct psi_group_cpu *groupc;
>  	u64 now;
>  
> +	if (static_branch_likely(&psi_disabled))
> +		return;
> +
>  	if (!task->pid)
>  		return;
>  

Reviewed-by: Chengming Zhou <zhouchengming@bytedance.com>

Thanks.

On Mon, Sep 25, 2023 at 10:21:43AM +0000, Haifeng Xu wrote:
> We could bail out early when psi was disabled.
> 
> Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>

Acked-by: Johannes Weiner <hannes@cmpxchg.org>

Can you please resend this with Peter Ziljstra <peterz@infradead.org>
in CC? Thanks

On 2023/9/25 20:31, Johannes Weiner wrote:
> On Mon, Sep 25, 2023 at 10:21:43AM +0000, Haifeng Xu wrote:
>> We could bail out early when psi was disabled.
>>
>> Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>
> 
> Acked-by: Johannes Weiner <hannes@cmpxchg.org>
> 
> Can you please resend this with Peter Ziljstra <peterz@infradead.org>
> in CC? Thanks

thanks, I'll send a new mail later.

We could bail out early when psi was disabled.

Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>
---
 kernel/sched/psi.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c
index 81fca77397f6..e74e14762d49 100644
--- a/kernel/sched/psi.c
+++ b/kernel/sched/psi.c
@@ -1005,6 +1005,9 @@ void psi_account_irqtime(struct task_struct *task, u32 delta)
 	struct psi_group_cpu *groupc;
 	u64 now;
 
+	if (static_branch_likely(&psi_disabled))
+		return;
+
 	if (!task->pid)
 		return;
 
-- 
2.25.1

On Tue, Sep 26, 2023 at 11:57:22AM +0000, Haifeng Xu wrote:
> We could bail out early when psi was disabled.
> 
> Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>

Thanks!

> ---
>  kernel/sched/psi.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c
> index 81fca77397f6..e74e14762d49 100644
> --- a/kernel/sched/psi.c
> +++ b/kernel/sched/psi.c
> @@ -1005,6 +1005,9 @@ void psi_account_irqtime(struct task_struct *task, u32 delta)
>  	struct psi_group_cpu *groupc;
>  	u64 now;
>  
> +	if (static_branch_likely(&psi_disabled))
> +		return;
> +
>  	if (!task->pid)
>  		return;
>  
> -- 
> 2.25.1
>

On 2023/9/26 19:57, Haifeng Xu wrote:
> We could bail out early when psi was disabled.
> 
> Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>
> ---
>  kernel/sched/psi.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c
> index 81fca77397f6..e74e14762d49 100644
> --- a/kernel/sched/psi.c
> +++ b/kernel/sched/psi.c
> @@ -1005,6 +1005,9 @@ void psi_account_irqtime(struct task_struct *task, u32 delta)
>  	struct psi_group_cpu *groupc;
>  	u64 now;
>  
> +	if (static_branch_likely(&psi_disabled))
> +		return;
> +
>  	if (!task->pid)
>  		return;
>  

Reviewed-by: Chengming Zhou <zhouchengming@bytedance.com>

Thanks.

The following commit has been merged into the sched/core branch of tip:

Commit-ID:     0c2924079f5a83ed715630680e338b3685a0bf7d
Gitweb:        https://git.kernel.org/tip/0c2924079f5a83ed715630680e338b3685a0bf7d
Author:        Haifeng Xu <haifeng.xu@shopee.com>
AuthorDate:    Tue, 26 Sep 2023 11:57:22 
Committer:     Peter Zijlstra <peterz@infradead.org>
CommitterDate: Fri, 13 Oct 2023 09:56:29 +02:00

sched/psi: Bail out early from irq time accounting

We could bail out early when psi was disabled.

Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Chengming Zhou <zhouchengming@bytedance.com>
Link: https://lore.kernel.org/r/20230926115722.467833-1-haifeng.xu@shopee.com
---
 kernel/sched/psi.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c
index 44a7877..519bc92 100644
--- a/kernel/sched/psi.c
+++ b/kernel/sched/psi.c
@@ -998,6 +998,9 @@ void psi_account_irqtime(struct task_struct *task, u32 delta)
 	struct psi_group_cpu *groupc;
 	u64 now;
 
+	if (static_branch_likely(&psi_disabled))
+		return;
+
 	if (!task->pid)
 		return;