On Fri, Aug 17, 2012 at 3:01 AM, Jani Nikula jani.nikula@linux.intel.com wrote:
On Thu, 16 Aug 2012, Jerome Glisse j.glisse@gmail.com wrote:
On Thu, Aug 16, 2012 at 11:13 AM, Jani Nikula jani.nikula@linux.intel.com wrote:
There's a bug [1] where the faster GMBUS transmissions fail with some CRTs, and the fix [2] is to fallback to GPIO bit-banging upon errors. As noted in the bug, the fix still leaves plenty of EDID dumps in dmesg, so some measures to reduce the EDID error messages would be most welcome.
[1] https://bugzilla.kernel.org/show_bug.cgi?id=45881 [2] http://thread.gmane.org/gmane.linux.kernel/1332810/focus=1341912
On Tue, 14 Aug 2012, Jerome Glisse j.glisse@gmail.com wrote:
On Tue, Aug 14, 2012 at 10:54 AM, Adam Jackson ajax@redhat.com wrote:
On 8/9/12 11:25 AM, j.glisse@gmail.com wrote:
From: Jerome Glisse jglisse@redhat.com
Limit printing bad edid information at one time per connector. Connector that are connected to a bad monitor/kvm will likely stay connected to the same bad monitor/kvm and it makes no sense to keep printing the bad edid message.
Do I understand correctly that bad_edid_counter is only reset when you reboot or reload the module? So if you have a laptop that you connect to the monitor at home, the monitor at the office, the projector in the meeting room, and to a TV somewhere else, etc, the message about bad EDID will only printed once? I don't think that's good. But please do correct me if I'm wrong.
I wanted to reset the counter any time the connector is connected to something with good edid but i did not do that in the end. I can do a patch on top if you think it would be nicer. That way only thing with bad edid will be printed once and assuming you don't repeatly alternate btw good and bad edid device you would not get spam.
IMHO this is, with or without the additional patch, overengineering the logic to print out error messages.
For me, as a developer, this would be annoying because, to debug an EDID issue, I'd have to reload the module, connect to something with "good" EDID in between, or patch this out, to repeat a problem. I might have to ask a tester or a bug reporter to do the same.
Also, in the referenced bug, the first problem with GMBUS would disable error messages, and the fallback retry with GPIO bit-banging would no longer produce messages even if that failed too.
If you set drm.debug=4 my patch will keep printing bad edid and possibly spam your log. So it's not harder for developer. I restricted the spamming to when some one is asking for debug.
Signed-off-by: Jerome Glisse jglisse@redhat.com
I guess. I don't see why we don't just move it into DRM_DEBUG_KMS if we're going to suppress it, but this does what it says on the box.
Reviewed-by: Adam Jackson ajax@redhat.com
- ajax
I think there is still value in getting at least once the bad edid.
I think the raw edid dumps should be DEBUG level no matter what. Perhaps some of the other messages could use WARNING/DEBUG too. And with that, and my comment above, I not sure there really needs to be all that logic to count errors and act differently further on.
No, i do think we want bad edid as normal log at least once per connector and we definitely don't want to spam bomb the log messages.
Well, at least we agree on silencing the dmesg here. ;)
I'd be happy with very simply adjusting the loglevel of the messages, so that I can also very simply adjust the amount of messages I get. Or ask a bug reported to do drm.debug=0xe instead of trying to ensure they follow a bunch of steps in between. But I'm not going to bikeshed further if others think the patch here is the way to go.
The patch aim was mostly with server where we dont want to spam bomb error log but where we still want to be able to get bad edid without having to ask for a reboot which on server is very much appreciated.
Cheers, Jerome