Subject: Re: [PATCHv11 2/4] genirq: Provide a snapshot mechanism for interrupt statistics

From: Thomas Gleixner <[email-masked]>
Date: Tue, 05 Mar 2024 17:57:40 +0100

On Tue, Mar 05 2024 at 18:57, Bitao Hu wrote:
> On 2024/3/4 22:24, Thomas Gleixner wrote:
> "GENERIC_IRQ_STAT_SNAPSHOT" visible to the user. However, after
> analyzing the previous emails, it seems that what you were actually
> proposing was to directly disable "GENERIC_IRQ_STAT_SNAPSHOT" when
> "SOFTLOCKUP_DETECTOR_INTR_STORM" is not enabled, as a way to save
> memory. If my current understanding is correct, then the code for that
> part would look something like the following.

Correct.

> diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
> index 2531f3496ab6..a28e5ac5fc79 100644
> --- a/kernel/irq/Kconfig
> +++ b/kernel/irq/Kconfig
> @@ -108,6 +108,10 @@ config GENERIC_IRQ_MATRIX_ALLOCATOR
>   config GENERIC_IRQ_RESERVATION_MODE
>          bool
>
> +# Snapshot for interrupt statistics
> +config GENERIC_IRQ_STAT_SNAPSHOT
> +       bool
> +
>   # Support forced irq threading
>   config IRQ_FORCED_THREADING
>          bool
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index 49f652674bd8..899b69fcb598 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -1032,6 +1032,7 @@ config SOFTLOCKUP_DETECTOR
>   config SOFTLOCKUP_DETECTOR_INTR_STORM
>          bool "Detect Interrupt Storm in Soft Lockups"
>          depends on SOFTLOCKUP_DETECTOR && IRQ_TIME_ACCOUNTING
> +       select GENERIC_IRQ_STAT_SNAPSHOT

This goes into the patch which adds the lockup detector parts.

Thanks,

        tglx