svn commit: r278479 - in head: etc sys/kern

[Adrian Chadd]

On 10 February 2015 at 06:16, John Baldwin <jhb at freebsd.org> wrote:
> On Monday, February 09, 2015 11:13:51 PM Rui Paulo wrote:
>> Author: rpaulo
>> Date: Mon Feb  9 23:13:50 2015
>> New Revision: 278479
>> URL: https://svnweb.freebsd.org/changeset/base/278479
>>
>> Log:
>>   Notify devd(8) when a process crashed.
>>
>>   This change implements a notification (via devctl) to userland when
>>   the kernel produces coredumps after a process has crashed.
>>   devd can then run a specific command to produce a human readable crash
>>   report.  The command is most usually a helper that runs gdb/lldb
>>   commands on the file/coredump pair.  It's possible to use this
>>   functionality for implementing automatic generation of crash reports.
>>
>>   devd(8) will be notified of the full path of the binary that crashed and
>>   the full path of the coredump file.
>
> I think this is a very useful feature and I think this is fine to be in the
> tree as-is for now.  My only note is that this is a bit of feature creep for
> devd (this isn't a device notification, this is a system event notification).
> As such, I think it might be worth thinking if we (collectively) want to think
> about having a separate framework at all for system event notification.  You
> could possibly publish other interesting events this way.  For example, Isilon
> currently has a patch to log(9) Witness LORs.  I personally think it's a bit
> hackish and potentially unreliable.  A much nicer interface if you want to
> capture such things would be to publish an event for each logged LOR instead.
> Machine checks are another example of something that might be nice to publish
> (though you could possibly make the case that those would not be inappropriate
> to publish via devd since actual hardware is involved).  Disk and PCI errors
> are another class of thing that it would be nice to publish in an easier to
> programmaticaly parse manner.

Cool, so someone's going to add multi-subscriber support to /dev/devctl ?

I think devd grows these things because it's easier than teaching the
devctl interface to support multiple listeners.




-adrian