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Sender: Ingo Molnar <mingo.kernel.org@gmail.com>
Date:   Tue, 19 Sep 2023 09:21:35 +0200
From:   Ingo Molnar <mingo@kernel.org>
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Ankur Arora <ankur.a.arora@oracle.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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Subject: Re: [PATCH v2 7/9] sched: define TIF_ALLOW_RESCHED
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* Thomas Gleixner <tglx@linutronix.de> wrote:

> Additionally we have PREEMPT=FULL which utilizes every zero transition
> of preeempt_count as a potential preemption point.

Just to complete this nice new entry to Documentation/sched/: in 
PREEMPT=FULL there's also IRQ-return driven preemption of kernel-mode code, 
at almost any instruction boundary the hardware allows, in addition to the 
preemption driven by regular zero transition of preempt_count in 
syscall/kthread code.

Thanks,

	Ingo