Re: [PATCH] Preserve task state in reentrant calls to ___wait_event

2015-11-07 Thread Peter Zijlstra
On Fri, Nov 06, 2015 at 08:44:08PM +, Chris Bainbridge wrote: > I am assuming here that wait_event_timeout() is supposed to support reentrant > calls. Not really. It is sort of allowed, provided the inner one will rarely block. And therefore the outer one will mostly work. > If not, perhaps

Re: [PATCH] Preserve task state in reentrant calls to ___wait_event

2015-11-07 Thread Chris Bainbridge
On Fri, Nov 06, 2015 at 08:44:08PM +, Chris Bainbridge wrote: > -#define ___wait_event(wq, condition, state, exclusive, ret, cmd) \ > +#define ___wait_event(wq, condition, nstate, exclusive, ret, cmd)\ > ({ \ >

Re: [PATCH] Preserve task state in reentrant calls to ___wait_event

2015-11-07 Thread Peter Zijlstra
On Fri, Nov 06, 2015 at 08:44:08PM +, Chris Bainbridge wrote: > I am assuming here that wait_event_timeout() is supposed to support reentrant > calls. Not really. It is sort of allowed, provided the inner one will rarely block. And therefore the outer one will mostly work. > If not, perhaps

Re: [PATCH] Preserve task state in reentrant calls to ___wait_event

2015-11-07 Thread Chris Bainbridge
On Fri, Nov 06, 2015 at 08:44:08PM +, Chris Bainbridge wrote: > -#define ___wait_event(wq, condition, state, exclusive, ret, cmd) \ > +#define ___wait_event(wq, condition, nstate, exclusive, ret, cmd)\ > ({ \ >

Re: [PATCH] Preserve task state in reentrant calls to ___wait_event

2015-11-06 Thread Rafael J. Wysocki
On Friday, November 06, 2015 08:44:08 PM Chris Bainbridge wrote: > In the ACPI SBS initialisation, a reentrant call to wait_event_timeout() > causes an intermittent boot stall of several minutes usually following > the "Switching to clocksource tsc" message. This stall is caused by: > > 1.

[PATCH] Preserve task state in reentrant calls to ___wait_event

2015-11-06 Thread Chris Bainbridge
In the ACPI SBS initialisation, a reentrant call to wait_event_timeout() causes an intermittent boot stall of several minutes usually following the "Switching to clocksource tsc" message. This stall is caused by: 1. drivers/acpi/sbshc.c wait_transaction_complete() calls wait_event_timeout():

Re: [PATCH] Preserve task state in reentrant calls to ___wait_event

2015-11-06 Thread Rafael J. Wysocki
On Friday, November 06, 2015 08:44:08 PM Chris Bainbridge wrote: > In the ACPI SBS initialisation, a reentrant call to wait_event_timeout() > causes an intermittent boot stall of several minutes usually following > the "Switching to clocksource tsc" message. This stall is caused by: > > 1.

[PATCH] Preserve task state in reentrant calls to ___wait_event

2015-11-06 Thread Chris Bainbridge
In the ACPI SBS initialisation, a reentrant call to wait_event_timeout() causes an intermittent boot stall of several minutes usually following the "Switching to clocksource tsc" message. This stall is caused by: 1. drivers/acpi/sbshc.c wait_transaction_complete() calls wait_event_timeout():