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From: Adrian Chadd <adrian@freebsd.org>
To: Alexander Motin <mav@freebsd.org>
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Subject: how are callouts handled in cpu_idle() ?
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Hi,

What happens if this occurs:

* cpu_idle() is entered
* you enter critical_enter() and call cpu_idleclock()
* an interrupt occurs, scheduling an immediate callout
* .. but you've already set the clock register, so it won't be
serviced until the wait returns.

Perhaps interrupts have to be disabled before critical_enter() and
cpu_idletick() to ensure an interrupt-driven callout doesn't get
delayed?


Adrian