mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Peter Zijlstra <peterz@infradead.org>
To: Wladislav Wiebe <wladislav.wiebe@nokia.com>
Cc: anna-maria@linutronix.de, frederic@kernel.org, mingo@kernel.org,
	tglx@linutronix.de, akpm@linux-foundation.org,
	bigeasy@linutronix.de, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] irq: add support for warning on long-running IRQ handlers
Date: Mon, 30 Jun 2025 15:25:17 +0200	[thread overview]
Message-ID: <20250630132517.GM1613376@noisy.programming.kicks-ass.net> (raw)
In-Reply-To: <20250630124721.18232-1-wladislav.wiebe@nokia.com>

On Mon, Jun 30, 2025 at 02:46:44PM +0200, Wladislav Wiebe wrote:
> Introduce a new option CONFIG_IRQ_LATENCY_WARN that enables warnings when
> IRQ handlers take an unusually long time to execute.
> 
> When triggered, the warning includes the CPU, IRQ number, handler address,
> name, and execution duration, for example:
> 
>   [CPU0] latency on IRQ[787:bad_irq_handler+0x1/0x34 [bad_irq]], took: 5 jiffies (~50 ms)
> 
> To keep runtime overhead minimal, this implementation uses a jiffies-based
> timing mechanism. While coarse, it is sufficient to detect problematic IRQs.

local_clock() was found to be excessively expensive?

  reply	other threads:[~2025-06-30 13:25 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-06-30 12:46 Wladislav Wiebe
2025-06-30 13:25 ` Peter Zijlstra [this message]
2025-06-30 13:59   ` Wladislav Wiebe
2025-07-02  9:06     ` Peter Zijlstra
2025-07-02  9:14       ` Wladislav Wiebe
2025-06-30 15:42 ` Thomas Gleixner
2025-07-01  6:10   ` Wladislav Wiebe
2025-07-01  7:37     ` Thomas Gleixner
2025-07-15  8:23       ` Wladislav Wiebe

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20250630132517.GM1613376@noisy.programming.kicks-ass.net \
    --to=peterz@infradead.org \
    --cc=akpm@linux-foundation.org \
    --cc=anna-maria@linutronix.de \
    --cc=bigeasy@linutronix.de \
    --cc=frederic@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=tglx@linutronix.de \
    --cc=wladislav.wiebe@nokia.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®