On Fri, 14 May 2010, Rafael J. Wysocki wrote: > > > How do you handle situations where the CPU is currently idle but an > > > event (such as I/O completion) is expected to occur in the near future? > > > You don't want to power-off and reboot then, do you? > > > > The idle code looks at next_timer_interrupt() value, then if the > > next timer event if far enough ahead, the system powers down and > > wakes to the timer interrupt. It also wakes to device interrupts. > > For the record, waking to interrupts doesn't work on quite some systems > (like ACPI-based PCs for one example). Ironically, it appears that ACPI-based PCs are in a position to benefit more from opportunistic suspend and suspend blockers than are embedded systems -- and yet they are being proposed for use on cell phones rather than on desktops. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
