Re: SCHED_YIELD undeclared with Trond's NFS patch w/2.4.19-pre2-ac2

[Richard B. Johnson]

On Thu, 7 Mar 2002, Steven A. DuChene wrote:

> I am attempting to apply Trond's linux-2.4.18-NFS_ALL.dif patch to 2.4.19-pre2-ac2
> I get the patch to apply once I massage fs/nfs/inode.c a little bit but when I try
> to compile it I get:
> 
> svcsock.c: In function `svc_recv':
> svcsock.c:987: `SCHED_YIELD' undeclared (first use in this function)
> svcsock.c:987: (Each undeclared identifier is reported only once
> svcsock.c:987: for each function it appears in.)
> make[3]: *** [svcsock.o] Error 1
> make[3]: Leaving directory `/usr/src/linux-2.4.X/net/sunrpc'
> make[2]: *** [first_rule] Error 2
> 

> Now I know there were some changes because of the O(1) stuff in the ac2 patch but
> what is the process for eliminating references to SCHED_YIELD?
> -- 
> Steven A. DuChene      [e-mail]
>                       [e-mail]

You need to change loops that do something like:

    while(something)
    {
        current->policy |= SCHED_YIELD;
        schedule();
    }
    
    to:

    while(something)
        sys_sched_yield();

Reference:

On Tue, 26 Feb 2002, Richard B. Johnson wrote:

> On Tue, 26 Feb 2002, Davide Libenzi wrote:
> >
> > In 2.5 yield() maps to sys_sched_yield(). You can handle it in the same
> > way in your includes if version <= 2.4.
>
> It's not exported as well as not defined in a header! It results in
> an undefined symbol in the module.

You can try to ask Marcelo to add a line in include/linux/sched.h and one
in kernel/ksym.c
In this way a compatibility interface can be achieved for code that needs it.

- Davide

Cheers,
Dick Johnson

Penguin : Linux version 2.4.18 on an i686 machine (799.53 BogoMips).

	Bill Gates? Who?