Re: Q about do_fork()

["Joseph A. Knapka" <jknapka@earthlink.net>]

petur thors wrote:
> John Levon wrote:
> > I also can't see (looking quickly) any problem with the routine being
> multi-threaded
> >
> > john
> >
> > --
> > "I am a conscientious man, when I throw rocks at seabirds I leave no tern
> > unstoned."
> >    - Ogden Nash
> 
> Yes, thanks. But then there must be? a lock of some kind in
> alloc_task_struct
> in do_fork().Right? Two processes canīt allocate free page frames (8kb
> task_union) at the exact same moment.(please correct me if iīm wrong).
> Mucho thanks

The actual page allocation is protected by the per-zone lock
in page_alloc.c:rmqueue(), so locking alloc_task_struct() should
not be necessary.

-- Joe
 
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