Re: [RFC PATCH 6/7] core/metricfs: expose x86-specific irq information through metricfs

From: Paolo Bonzini <pbonzini@redhat.com>
To: Thomas Gleixner <tglx@linutronix.de>,
	Jonathan Adams <jwadams@google.com>,
	linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Cc: netdev@vger.kernel.org, kvm@vger.kernel.org,
	Greg KH <gregkh@linuxfoundation.org>,
	Jim Mattson <jmattson@google.com>,
	David Rientjes <rientjes@google.com>
Subject: Re: [RFC PATCH 6/7] core/metricfs: expose x86-specific irq information through metricfs
Date: Thu, 13 Aug 2020 16:10:25 +0200	[thread overview]
Message-ID: <ffeac3eb-fbd5-a605-c6a5-0456813bd918@redhat.com> (raw)
In-Reply-To: <87a6yylp4x.fsf@nanos.tec.linutronix.de>

On 13/08/20 14:13, Thomas Gleixner wrote:
>>>> Add metricfs support for displaying percpu irq counters for x86.
>>>> The top directory is /sys/kernel/debug/metricfs/irq_x86.
>>>> Then there is a subdirectory for each x86-specific irq counter.
>>>> For example:
>>>>
>>>>    cat /sys/kernel/debug/metricfs/irq_x86/TLB/values
>>> What is 'TLB'? I'm not aware of any vector which is named TLB.
>> There's a "TLB" entry in /proc/interrupts.
> It's TLB shootdowns and not TLB.

Yes but it's using the shortcut name on the left of the table.

> +METRICFS_ITEM(LOC, apic_timer_irqs, "Local timer interrupts");
> +METRICFS_ITEM(SPU, irq_spurious_count, "Spurious interrupts");
> +METRICFS_ITEM(PMI, apic_perf_irqs, "Performance monitoring interrupts");
> +METRICFS_ITEM(IWI, apic_irq_work_irqs, "IRQ work interrupts");
> +METRICFS_ITEM(RTR, icr_read_retry_count, "APIC ICR read retries");
> +#endif
> +METRICFS_ITEM(PLT, x86_platform_ipis, "Platform interrupts");
> +#ifdef CONFIG_SMP
> +METRICFS_ITEM(RES, irq_resched_count, "Rescheduling interrupts");
> +METRICFS_ITEM(CAL, irq_call_count, "Function call interrupts");
> +METRICFS_ITEM(TLB, irq_tlb_count, "TLB shootdowns");

Paolo