[parisc-linux] Progress - Update

John David Anglin dave@hiauly1.hia.nrc.ca
Wed, 1 Dec 1999 13:33:09 -0500 (EST)


> 
> > 
> > Furthermore we have to care for cases like:
> > 
> > 	var = 1;
> > x=0;
> > CPU0		CPU1
> > xchg(&var,x);	test_and_set_bit(0, &var);
> 
> Umm. Does anyone actually rely on that ? Im not sure the non x86 ports have
> that property

Also, we may need to flush the cache line for &var.  The coding in buffer.c
which caused the original panic in xchg looks dubiousin this regoard:

        /* Update the reuse list */
		tail->b_next_free = xchg(&reuse_list, NULL);
		reuse_list = bh;


-- 
J. David Anglin                                  dave.anglin@nrc.ca
National Research Council of Canada              (613) 990-0752 (FAX: 952-6605)