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Message-ID: <2318167.LMB5TD3duT@vostro.rjw.lan>
Date: Thu, 02 Oct 2014 01:30:22 +0200
From: "Rafael J. Wysocki" <rjw@...ysocki.net>
To: "dbasehore ." <dbasehore@...omium.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>,
linux-kernel <linux-kernel@...r.kernel.org>,
xen-devel@...ts.xenproject.org,
Laxman Dewangan <ldewangan@...dia.com>,
Ian Campbell <ian.campbell@...rix.com>,
Linux-pm mailing list <linux-pm@...r.kernel.org>,
Pavel Machek <pavel@....cz>, Len Brown <len.brown@...el.com>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
Thomas Gleixner <tglx@...utronix.de>,
Eric Biederman <ebiederm@...ssion.com>
Subject: Re: [Xen-devel] [PATCH v1 1/2] genirq: Fix error path for resuming irqs
On Wednesday, October 01, 2014 04:01:33 PM dbasehore . wrote:
> dpm_resume_noirq is not early enough for the Xen stuff, but should be
> early enough for other stuff. This patch is mostly just a bandage on
> top of the broken IRQF_EARLY_RESUME code.
>
> We may consider getting rid of IRQF_EARLY_RESUME and having Xen
> register its own syscore resume function to enable whatever irq it
> needs.
I'd very much prefer that.
> I'd be fine with that since some rtc drivers started using
> IRQF_EARLY_RESUME. I can't think of any reason those drivers would
> need to be resumed early. This way, the flag wouldn't even be there
> for people to mistakenly add.
There seem to be some ordering issues they are trying to solve this way,
but I think those issues can and should be addressed differently.
> On Wed, Oct 1, 2014 at 3:30 PM, Rafael J. Wysocki <rjw@...ysocki.net> wrote:
> > On Thursday, October 02, 2014 12:25:08 AM Rafael J. Wysocki wrote:
> >> On Wednesday, October 01, 2014 01:48:39 PM dbasehore . wrote:
> >> > Adding maintainers for affected systems to this CL for review.
> >> >
> >> > On Mon, Jul 7, 2014 at 8:33 AM, Konrad Rzeszutek Wilk
> >> > <konrad.wilk@...cle.com> wrote:
> >> > > On Fri, Jun 27, 2014 at 05:04:24PM -0700, Derek Basehore wrote:
> >> > >> In the case of a late abort to suspend/hibernate, irqs marked with
> >> > >> IRQF_EARLY_RESUME will not be enabled. This is due to syscore_resume not getting
> >> > >> called on these paths.
> >> > >>
> >> > >> This can happen with a pm test for platform, a late wakeup irq, and other
> >> > >> instances. This change removes the function from syscore and calls it explicitly
> >> > >> in suspend, hibernate, etc.
> >> > >>
> >> > >> This regression was introduced in 9bab0b7f "genirq: Add IRQF_RESUME_EARLY"
> >> > >>
> >> > >> Signed-off-by: Derek Basehore <dbasehore@...omium.org>
> >> > >
> >> > > Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
> >> > >
> >> > > on the Xen side.
> >> > >> ---
> >> > >> drivers/base/power/main.c | 5 ++++-
> >> > >> drivers/xen/manage.c | 5 ++++-
> >> > >> include/linux/interrupt.h | 1 +
> >> > >> include/linux/pm.h | 2 +-
> >> > >> kernel/irq/pm.c | 17 +++--------------
> >> > >> kernel/kexec.c | 2 +-
> >> > >> kernel/power/hibernate.c | 6 +++---
> >> > >> kernel/power/suspend.c | 2 +-
> >> > >> 8 files changed, 18 insertions(+), 22 deletions(-)
> >> > >>
> >> > >> diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
> >> > >> index bf41296..a087473 100644
> >> > >> --- a/drivers/base/power/main.c
> >> > >> +++ b/drivers/base/power/main.c
> >> > >> @@ -712,8 +712,10 @@ static void dpm_resume_early(pm_message_t state)
> >> > >> * dpm_resume_start - Execute "noirq" and "early" device callbacks.
> >> > >> * @state: PM transition of the system being carried out.
> >> > >> */
> >> > >> -void dpm_resume_start(pm_message_t state)
> >> > >> +void dpm_resume_start(pm_message_t state, bool enable_early_irqs)
> >> > >> {
> >> > >> + if (enable_early_irqs)
> >> > >> + early_resume_device_irqs();
> >>
> >> This conflicts with some changes I've already queued up for merging.
> >>
> >> Why don't you do that in dpm_resume_noirq() directly? Also why do we need
> >> the extra argument here? The only case when we pass 'false' apprears to be
> >> the Xen one, so perhaps we can use a special PM_EVENT_XEN flag or something
> >> similar to indicate that? Honestly, I don't want to litter the regular suspend
> >> code with Xen-specific stuff like this.
> >
> > BTW, is dpm_resume_noirq() early enough? What about the time we bring up
> > the non-boot CPUs? Don't we need to call the early_resume_device_irqs()
> > thing before that?
> >
> >> > >> dpm_resume_noirq(state);
> >> > >> dpm_resume_early(state);
> >> > >> }
> >> > >> @@ -1132,6 +1134,7 @@ static int dpm_suspend_noirq(pm_message_t state)
> >> > >> if (error) {
> >> > >> suspend_stats.failed_suspend_noirq++;
> >> > >> dpm_save_failed_step(SUSPEND_SUSPEND_NOIRQ);
> >> > >> + early_resume_device_irqs();
> >> > >> dpm_resume_noirq(resume_event(state));
> >> > >> } else {
> >> > >> dpm_show_time(starttime, state, "noirq");
> >> > >> diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c
> >> > >> index c3667b2..d387cdf 100644
> >> > >> --- a/drivers/xen/manage.c
> >> > >> +++ b/drivers/xen/manage.c
> >> > >> @@ -68,6 +68,7 @@ static int xen_suspend(void *data)
> >> > >> err = syscore_suspend();
> >> > >> if (err) {
> >> > >> pr_err("%s: system core suspend failed: %d\n", __func__, err);
> >> > >> + early_resume_device_irqs();
> >> > >> return err;
> >> > >> }
> >> > >>
> >> > >> @@ -92,6 +93,8 @@ static int xen_suspend(void *data)
> >> > >> xen_timer_resume();
> >> > >> }
> >> > >>
> >> > >> + early_resume_device_irqs();
> >> > >> +
> >> > >> syscore_resume();
> >> > >>
> >> > >> return 0;
> >> > >> @@ -137,7 +140,7 @@ static void do_suspend(void)
> >> > >>
> >> > >> raw_notifier_call_chain(&xen_resume_notifier, 0, NULL);
> >> > >>
> >> > >> - dpm_resume_start(si.cancelled ? PMSG_THAW : PMSG_RESTORE);
> >> > >> + dpm_resume_start(si.cancelled ? PMSG_THAW : PMSG_RESTORE, false);
> >> > >>
> >> > >> if (err) {
> >> > >> pr_err("failed to start xen_suspend: %d\n", err);
> >> > >> diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
> >> > >> index 698ad05..7f390e3 100644
> >> > >> --- a/include/linux/interrupt.h
> >> > >> +++ b/include/linux/interrupt.h
> >> > >> @@ -193,6 +193,7 @@ extern void irq_wake_thread(unsigned int irq, void *dev_id);
> >> > >> /* The following three functions are for the core kernel use only. */
> >> > >> extern void suspend_device_irqs(void);
> >> > >> extern void resume_device_irqs(void);
> >> > >> +extern void early_resume_device_irqs(void);
> >> > >> #ifdef CONFIG_PM_SLEEP
> >> > >> extern int check_wakeup_irqs(void);
> >> > >> #else
> >> > >> diff --git a/include/linux/pm.h b/include/linux/pm.h
> >> > >> index 72c0fe0..ae5b26a 100644
> >> > >> --- a/include/linux/pm.h
> >> > >> +++ b/include/linux/pm.h
> >> > >> @@ -677,7 +677,7 @@ struct dev_pm_domain {
> >> > >>
> >> > >> #ifdef CONFIG_PM_SLEEP
> >> > >> extern void device_pm_lock(void);
> >> > >> -extern void dpm_resume_start(pm_message_t state);
> >> > >> +extern void dpm_resume_start(pm_message_t state, bool enable_early_irqs);
> >> > >> extern void dpm_resume_end(pm_message_t state);
> >> > >> extern void dpm_resume(pm_message_t state);
> >> > >> extern void dpm_complete(pm_message_t state);
> >> > >> diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c
> >> > >> index abcd6ca..b07dc9c 100644
> >> > >> --- a/kernel/irq/pm.c
> >> > >> +++ b/kernel/irq/pm.c
> >> > >> @@ -60,26 +60,15 @@ static void resume_irqs(bool want_early)
> >> > >> }
> >> > >>
> >> > >> /**
> >> > >> - * irq_pm_syscore_ops - enable interrupt lines early
> >> > >> + * early_resume_device_irqs - enable interrupt lines early
> >> > >> *
> >> > >> * Enable all interrupt lines with %IRQF_EARLY_RESUME set.
> >> > >> */
> >> > >> -static void irq_pm_syscore_resume(void)
> >> > >> +void early_resume_device_irqs(void)
> >> > >> {
> >> > >> resume_irqs(true);
> >> > >> }
> >> > >> -
> >> > >> -static struct syscore_ops irq_pm_syscore_ops = {
> >> > >> - .resume = irq_pm_syscore_resume,
> >> > >> -};
> >> > >> -
> >> > >> -static int __init irq_pm_init_ops(void)
> >> > >> -{
> >> > >> - register_syscore_ops(&irq_pm_syscore_ops);
> >> > >> - return 0;
> >> > >> -}
> >> > >> -
> >> > >> -device_initcall(irq_pm_init_ops);
> >> > >> +EXPORT_SYMBOL_GPL(early_resume_device_irqs);
> >> > >>
> >> > >> /**
> >> > >> * resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs()
> >> > >> diff --git a/kernel/kexec.c b/kernel/kexec.c
> >> > >> index 369f41a..272853b 100644
> >> > >> --- a/kernel/kexec.c
> >> > >> +++ b/kernel/kexec.c
> >> > >> @@ -1700,7 +1700,7 @@ int kernel_kexec(void)
> >> > >> local_irq_enable();
> >> > >> Enable_cpus:
> >> > >> enable_nonboot_cpus();
> >> > >> - dpm_resume_start(PMSG_RESTORE);
> >> > >> + dpm_resume_start(PMSG_RESTORE, true);
> >> > >> Resume_devices:
> >> > >> dpm_resume_end(PMSG_RESTORE);
> >> > >> Resume_console:
> >> > >> diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
> >> > >> index fcc2611..1d6dd56 100644
> >> > >> --- a/kernel/power/hibernate.c
> >> > >> +++ b/kernel/power/hibernate.c
> >> > >> @@ -325,7 +325,7 @@ static int create_image(int platform_mode)
> >> > >> platform_finish(platform_mode);
> >> > >>
> >> > >> dpm_resume_start(in_suspend ?
> >> > >> - (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
> >> > >> + (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE, true);
> >> > >>
> >> > >> return error;
> >> > >> }
> >> > >> @@ -482,7 +482,7 @@ static int resume_target_kernel(bool platform_mode)
> >> > >> Cleanup:
> >> > >> platform_restore_cleanup(platform_mode);
> >> > >>
> >> > >> - dpm_resume_start(PMSG_RECOVER);
> >> > >> + dpm_resume_start(PMSG_RECOVER, true);
> >> > >>
> >> > >> return error;
> >> > >> }
> >> > >> @@ -574,7 +574,7 @@ int hibernation_platform_enter(void)
> >> > >> Platform_finish:
> >> > >> hibernation_ops->finish();
> >> > >>
> >> > >> - dpm_resume_start(PMSG_RESTORE);
> >> > >> + dpm_resume_start(PMSG_RESTORE, true);
> >> > >>
> >> > >> Resume_devices:
> >> > >> entering_platform_hibernation = false;
> >> > >> diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
> >> > >> index 4dd8822..3597c72 100644
> >> > >> --- a/kernel/power/suspend.c
> >> > >> +++ b/kernel/power/suspend.c
> >> > >> @@ -281,7 +281,7 @@ static int suspend_enter(suspend_state_t state, bool *wakeup)
> >> > >> if (need_suspend_ops(state) && suspend_ops->wake)
> >> > >> suspend_ops->wake();
> >> > >>
> >> > >> - dpm_resume_start(PMSG_RESUME);
> >> > >> + dpm_resume_start(PMSG_RESUME, true);
> >> > >>
> >> > >> Platform_finish:
> >> > >> if (need_suspend_ops(state) && suspend_ops->finish)
> >> > >> --
> >> > >> 2.0.0.526.g5318336
> >> > >>
> >> > >>
> >> > >> _______________________________________________
> >> > >> Xen-devel mailing list
> >> > >> Xen-devel@...ts.xen.org
> >> > >> http://lists.xen.org/xen-devel
> >> > --
> >> > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> >> > the body of a message to majordomo@...r.kernel.org
> >> > More majordomo info at http://vger.kernel.org/majordomo-info.html
> >> > Please read the FAQ at http://www.tux.org/lkml/
> >>
> >>
> >
> > --
> > I speak only for myself.
> > Rafael J. Wysocki, Intel Open Source Technology Center.
--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.
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