Messages in this thread | | | Date | Wed, 2 Dec 2020 13:36:48 +0100 | From | Peter Zijlstra <> | Subject | Re: [PATCH 4/5] irqtime: Move irqtime entry accounting after irq offset incrementation |
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On Wed, Dec 02, 2020 at 12:57:31PM +0100, Frederic Weisbecker wrote: > IRQ time entry is currently accounted before HARDIRQ_OFFSET or > SOFTIRQ_OFFSET are incremented. This is convenient to decide to which > index the cputime to account is dispatched. > > Unfortunately it prevents tick_irq_enter() from being called under > HARDIRQ_OFFSET because tick_irq_enter() has to be called before the IRQ > entry accounting due to the necessary clock catch up. As a result we > don't benefit from appropriate lockdep coverage on tick_irq_enter(). > > To prepare for fixing this, move the IRQ entry cputime accounting after > the preempt offset is incremented. This requires the cputime dispatch > code to handle the extra offset. > > Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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