Re: /proc/sys/kernel/pid_max issues

[Ingo Molnar]

* Arjan van de Ven <arjanv@xxxxxxxxxx> wrote:

> On Sun, Sep 12, 2004 at 10:30:00PM +1000, Anton Blanchard wrote:
> > 
> > Hmm can you point the 16bit counter out? I can create 1 million NPTL
> > threads on ppc64 easily, so why not?
> 
> /*
>  * the semaphore definition
>  */
> struct rw_semaphore {
>         /* XXX this should be able to be an atomic_t  -- paulus */
>         signed int              count;
> #define RWSEM_UNLOCKED_VALUE            0x00000000
> #define RWSEM_ACTIVE_BIAS               0x00000001
> #define RWSEM_ACTIVE_MASK               0x0000ffff
> 
> that counter is split in 2 16 bit entities....

the generic semaphore code can handle up to ~2^31 waiters. I once tried
it on x86, it seems to work fine.

	Ingo
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