Messages in this thread | | | Date | Mon, 23 Feb 2009 14:44:17 -0800 | Subject | Re: [RFC][PATCH 2/2] PM: Rework handling of interrupts during suspend-resume | From | Arve Hjønnevåg <> |
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On Mon, Feb 23, 2009 at 2:23 PM, Rafael J. Wysocki <rjw@sisk.pl> wrote: > On Monday 23 February 2009, Arve Hjønnevåg wrote: >> On Sun, Feb 22, 2009 at 9:39 AM, Rafael J. Wysocki <rjw@sisk.pl> wrote: >> > From: Rafael J. Wysocki <rjw@sisk.pl> >> > >> > Introduce two helper functions allowing us to disable device >> > interrupts (at the IO-APIC level) during suspend or hibernation >> > and enable them during the subsequent resume, respectively, so that >> > the timer interrupts are enabled while "late" suspend callbacks and >> > "early" resume callbacks provided by device drivers are being >> > executed. >> > >> > Use these functions to rework the handling of interrupts during >> > suspend (hibernation) and resume. Namely, interrupts will only be >> > disabled on the CPU right before suspending sysdevs, while device >> > interrupts will be disabled (at the IO-APIC level), with the help of >> > the new helper function, before calling "late" suspend callbacks >> > provided by device drivers and analogously during resume. >> > >> >> What impact does this have on wakeup interrupts? Unless you add a >> check, after masking all interrupt at the CPU, to abort suspend if any >> wakeup interrupt has IRQ_PENDING set I think you will loose wakeup >> interrupts (at least for irqs that use default_disable). > > I _think_ they would have to be reenabled after we've called > local_irq_disable().
Are you talking about the irq_chip switching from enabled interrupts to wake interrupts? It is not enough for the irq_chip to reenable the hardware interrupt. If the interrupt is edge triggered and occurred after you disabled it, but before local_irq_disable, the only record of it is the IRQ_PENDING flag.
-- Arve Hjønnevåg -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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