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From: Thomas Gleixner <tglx@linutronix.de>
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To: paulmck@kernel.org
Cc: LKML <linux-kernel@vger.kernel.org>, Daniel J Blueman
 <daniel@quora.org>, John Stultz <jstultz@google.com>, Waiman Long
 <longman@redhat.com>, Peter Zijlstra <peterz@infradead.org>, Dave Hansen
 <dave.hansen@linux.intel.com>, Tony Luck <tony.luck@intel.com>, Borislav
 Petkov <bp@alien8.de>, Stephen Boyd <sboyd@kernel.org>, Scott Hamilton
 <scott.hamilton@eviden.com>
Subject: Re: clocksource: Reduce watchdog readout delay limit to prevent
 false positives
In-Reply-To: <308f260b-83c6-402e-9756-017be125bb44@paulmck-laptop>
References: <87bjjxc9dq.ffs@tglx>
 <90dce4d0-bd90-4321-95d8-c8dd1c121de0@paulmck-laptop>
 <878qeybwzy.ffs@tglx>
 <308f260b-83c6-402e-9756-017be125bb44@paulmck-laptop>
Date: Sat, 20 Dec 2025 09:37:40 +0100
Message-ID: <87tsxla6qz.ffs@tglx>
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On Fri, Dec 19 2025 at 16:18, Paul E. McKenney wrote:
> On Fri, Dec 19, 2025 at 11:13:05AM +0100, Thomas Gleixner wrote:
>> > My concern is that the patch below would force needless cs_watchdog_read()
>> > retries.
>> 
>> That's not the end of the world and way better than degrading the
>> watchdog further.
>
> But what you proposed is just a further tweak of the heuristics you so
> energetically decry above.

I fully agree that it is a bandaid fix, but it makes the machinery
consistent and correct. It prevents false positives, which are
inevitable in the current design. No?

Thanks,

        tglx