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From: Karl Mehltretter <kmehltretter@gmail.com>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
	 Thomas Gleixner <tglx@kernel.org>,
	Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
	 Frederic Weisbecker <frederic@kernel.org>,
	Clark Williams <clrkwllms@kernel.org>,
	 Boqun Feng <boqun@kernel.org>, Lyude Paul <lyude@redhat.com>,
	 Joel Fernandes <joelagnelf@nvidia.com>,
	Alexander Potapenko <glider@google.com>,
	 Marco Elver <elver@google.com>, Jonathan Corbet <corbet@lwn.net>,
	 Bradley Morgan <brads@mainlining.org>,
	linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
	 linux-rt-devel@lists.linux.dev,
	Shuah Khan <skhan@linuxfoundation.org>,
	 Randy Dunlap <rdunlap@infradead.org>,
	"Mukesh Kumar Chaurasiya (IBM)" <mkchauras@gmail.com>
Subject: Re: [PATCH v6] softirq: Preserve interrupt context during IRQ exit
Date: Thu, 15 Oct 2026 08:32:12 +0200	[thread overview]
Message-ID: <atByy9l7zW4TKtrK@gmail.com> (raw)
In-Reply-To: <20261014120524.5e6e6efe@gandalf.local.home>

On Wed, Oct 14, 2026 at 12:05:24PM +0100, Steven Rostedt wrote:
> LGTM.
> 
> So this handles the transition between hard irq and softirq?
> 
> I wish there was a way to get preempt count updated earlier on entering a
> hard irq so I can get rid of the transition bit in the trace recursion. As
> there's still places that can trigger a trace in the hard irq before
> preempt count is updated.
> 

Yes, this handles the hardirq-to-softirq transition on IRQ exit.

I am looking into whether the preempt count can be updated before any
traceable code can run, as a potential follow-up RFC.

If that works, it may allow the transition bit to be removed from trace
recursion.

Thanks,
Karl

  reply	other threads:[~2026-10-15  6:32 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-10-11  6:07 [PATCH v6] softirq: Preserve interrupt context during IRQ exit Karl Mehltretter
2026-10-11  9:15 ` Manuel Ebner
2026-10-11  9:31 ` Bradley Morgan
2026-10-12 19:08   ` Karl Mehltretter
2026-10-13 16:10 ` Sebastian Andrzej Siewior
2026-10-14 13:19 ` Frederic Weisbecker
2026-10-14 16:05 ` Steven Rostedt
2026-10-15  6:32   ` Karl Mehltretter [this message]
2026-10-15 12:48     ` Steven Rostedt

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