Re: Question about sched_yield()

Rusty Russell (rusty@rustcorp.com.au)
Thu, 20 Jun 2002 00:03:34 +1000


In message <Pine.LNX.3.96.1020619072548.1119D-100000@gatekeeper.tmr.com> you wr
ite:
> On Wed, 19 Jun 2002, Rusty Russell wrote:
>
> > On Mon, 17 Jun 2002 17:46:29 -0700
> > David Schwartz <davids@webmaster.com> wrote:
> > > "The sched_yield() function shall force the running thread to relinquish
the
> > > processor until it again becomes the head of its thread list. It takes no

> > > arguments."
> >
> > Notice how incredibly useless this definition is. It's even defined in ter
ms
> > of UP.
>
> I think you parse this differently than I, I see no reference to UP. The
> term "the processor" clearly (to me at least) means the processor running
> in that thread at the time of the yeild.
>
> The number of processors running in a single thread at any one time is an
> integer number in the range zero to one.

It's the word "until": "relinquish the processor until".

It's pretty clearly implied that it's going to "unrelinquish" *the
processor* at the end of this process.

So, by your definition, it can be scheduled on another CPU before it
becomes head of the thread list?

Rusty.

--
  Anyone who quotes me in their sig is an idiot. -- Rusty Russell.
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