Re: [Lse-tech] lockmeter results comparing 2.4.17, 2.5.3, and 2.5.5

[Linus Torvalds]

In article <[e-mail]>,
Andrew Morton  <[e-mail]> wrote:
>"Martin J. Bligh" wrote:
>> 
>> Seeing as people seem to be interested ... there are some big holders
>> of BKL around too - do_exit shows up badly (50ms in the data Hanna
>> posted, and I've seen that a lot before).
>
>That'll be where exit() takes down the tasks's address spaces.  
>zap_page_range().  That's a nasty one.

No, lock_kernel happens after exit_mm, and in fact I suspect it's not
really needed at all any more except for the current "sem_exit()". I
think most everything else is threaded already.

(Hmm.. Maybe disassociate_ctty() too).

So minimizing the BLK footprint in do_exit() should be pretty much
trivial: all the really interesting stuff should be ok already.

		Linus