Re: SUMMARY: Kernel Threads Usable By Mortals

Matthias Urlichs (smurf@smurf.noris.de)
Tue, 30 Apr 1996 13:26:38 +0100

In linux.dev.kernel, article <199604290239.WAA23830@huahaga.rutgers.edu=
>,
"David S. Miller" <davem@caip.rutgers.edu> writes:
>=20
> void acquire_lock(lock)
> {
> repeat:
> while(mutex_held(lock))
> yield();
> if(!mutex_try(lock))
> goto repeat;
> }
>=20
That while loop is still a busy wait. The fact that you explicitly give
other processes a chance to proceed doesn't change that.

Besides, if more than one process competes for the lock you can still h=
ave
a starvation problem.

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