[PATCH] Add ktrace records for user page faults

[Alexander Leidinger]

Quoting John Baldwin <jhb at freebsd.org> (from Mon, 2 May 2011 16:02:02 -0400):

> It is true that it would be nice to have the exact faulting address, though
> having page granularity has been sufficient for the few times I've actually
> used the address itself (e.g. I could figure out which page of libstdc++ a
> fault occurred on and narrow down from there as to which of the routines most
> likely was executed given what the app was doing at the time).  In my case
> knowing how much time was spent handling a page fault has been useful.
>
> Would we have to push this logic out of vm_fault and into every  
> trap() routine
> to get the original address?  That would make the patch quite a bit bigger
> (touching N MD files vs 1 MI file).

dtrace is not a solution here (in general, not to the exact-address problem)?

Bye,
Alexander.

-- 
I am looking for a honest man.
		-- Diogenes the Cynic

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