Re: vt_suspend / vt_resume

On 10/03/14 08:13, Andriy Gapon wrote:
> On 30/09/2014 08:47, Andriy Gapon wrote:
>> I think that currently vt_suspend / vt_resume are called at quite unsuitable
>> times.  For example, vt_suspend performs a vt switch which requires cooperation
>> from an X server, but that could be problematic given that some devices may
>> already be suspended.
>> I believe that it is better to do what sc(4) does and use power_suspend /
>> power_resume event handlers instead of device_suspend / device_resume methods.
>> power_suspend event is posted when a kernel has not entered any special state yet.
>>
>> What do you think?
>>
>
> So, I am now using the following patch and suspend/resume works 100% reliable
> for me, whereas previously there was a quite significant chance that the video
> subsystem would be in a very confused state after resuming.
>
> For example there could be an endless stream of error message and the screen
> would be frozen:
> drmn0: error: couldn't schedule ib
> error: [drm:pid1492:radeon_cs_ib_chunk] *ERROR* Failed to schedule IB !
>
> Or there could be an endless GPU reset loop in the radeon driver:
> drmn0: error: GPU lockup CP stall for more than 10000msec
> drmn0: warning: GPU lockup (waiting for 0x0000000000269544 last fence id
> 0x0000000000269523)
> error: [drm:pid1492:r600_ib_test] *ERROR* radeon: fence wait failed (-11).
> error: [drm:pid1492:radeon_ib_ring_tests] *ERROR* radeon: failed testing IB on
> GFX ring (-11).
> drmn0: error: ib ring test failed (-11).
> drmn0: info: GPU softreset: 0x00000003
>
> The patch (I am not sure if fbd_attach is the right place to register the event
> handlers):

It's not, I don't think, since fbd_attach() isn't called for all vt 
backends (e.g. the VGA and EFI backends don't call it). vt_fb_suspend() 
also only calls vt_suspend(), so it's probably best to put this in the 
core vt code.
-Nathan

> diff --git a/sys/dev/fb/fbd.c b/sys/dev/fb/fbd.c
> index ff2488d..923292a 100644
> --- a/sys/dev/fb/fbd.c
> +++ b/sys/dev/fb/fbd.c
> _at__at_ -316,6 +316,11 _at__at_ fbd_attach(device_t dev)
>   		return (ENXIO);
>   	err = fbd_register(sc->sc_info);
>
> +	EVENTHANDLER_REGISTER(power_suspend, vt_fb_suspend, NULL,
> +			      EVENTHANDLER_PRI_ANY);
> +	EVENTHANDLER_REGISTER(power_resume, vt_fb_resume, NULL,
> +			      EVENTHANDLER_PRI_ANY);
> +
>   	return (err);
>   }
>
> _at__at_ -332,22 +337,6 _at__at_ fbd_detach(device_t dev)
>   	return (err);
>   }
>
> -static int
> -fbd_suspend(device_t dev)
> -{
> -
> -	vt_fb_suspend();
> -	return (bus_generic_suspend(dev));
> -}
> -
> -static int
> -fbd_resume(device_t dev)
> -{
> -
> -	vt_fb_resume();
> -	return (bus_generic_resume(dev));
> -}
> -
>   static device_method_t fbd_methods[] = {
>   	/* Device interface */
>   	DEVMETHOD(device_probe,		fbd_probe),
> _at__at_ -355,8 +344,6 _at__at_ static device_method_t fbd_methods[] = {
>   	DEVMETHOD(device_detach,	fbd_detach),
>
>   	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
> -	DEVMETHOD(device_suspend,	fbd_suspend),
> -	DEVMETHOD(device_resume,	fbd_resume),
>
>   	{ 0, 0 }
>   };
>
>
>
>
> _______________________________________________
> freebsd-current_at_freebsd.org mailing list
> http://lists.freebsd.org/mailman/listinfo/freebsd-current
> To unsubscribe, send any mail to "freebsd-current-unsubscribe_at_freebsd.org"