From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sasha Levin <sasha.levin@oracle.com>
Subject: Re: [RFC 2/3] lockdep: be nice about compiling from userspace
Date: Thu, 25 Oct 2012 15:17:15 -0400
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Cc: penberg@kernel.org, mingo@redhat.com, peterz@infradead.org,
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To: Ingo Molnar <mingo@kernel.org>
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On 10/25/2012 01:06 PM, Ingo Molnar wrote:
> * Sasha Levin <sasha.levin@oracle.com> wrote:
>> Yes, we can wrap both static_obj() and debug_show_all_locks() 
>> with #ifndefs and let kvmtool provide it's own version of 
>> those two.
> 
> Only static_obj() - I see no immediate reason why you shouldn't 
> be able to utilize debug_show_all_locks(). 'vm debug -a' already 
> lists all backtraces on all vcpus - so 'vm debug lockdep -a' 
> could list all current locks and indicate which one is held and 
> by whom.

I'm not sure how we'd make debug_show_all_locks() work in userspace
since it would require us to wrap do_each_thread() & friends to iterate
over all our task_structs.

I was thinking about writing a corresponding debug_show_all_locks() that
would simply iterate a list of our dummy task_structs.


Thanks,
Sasha