On Mon, Oct 09, 2006 at 03:45:28PM -0700, Jason Thorpe wrote:
> 
> On Oct 9, 2006, at 1:43 AM, Juergen Hannken-Illjes wrote:
> 
> >The latter.  Call xxx_set() and xxx_get() with locks held.
> 
> For setspecific, I could add a setspecific_nowait, but I'm concerned  
> about what the failure mode is supposed to be if it were to fail...  
> would you unwind your state, and try to set the data some other way,  
> or would you fail the operation in some fashion?

I will fail like this:

  int
  fstrans_start(struct mount *mp, int flags)
  {
	int error;
	struct fstrans_state *fts;

	if ((fts = lwp_getspecific(curlwp, fstrans_state_key)) == NULL) {
		if ((flags & FSTRANS_NOWAIT) != 0) {
			if ((fts = pool_get(&fstrans_spl, PR_NOWAIT)) == NULL)
				return EWOULDBLOCK;
			if ((error = lwp_setspecific_nowait(curlwp,
			    fstrans_state_key, fts)) != 0) {
				pool_put(&fstrans_spl, fts);
				return error;
			}
		} else {
			fts = pool_get(&fstrans_spl, 0);
			lwp_setspecific(curlwp, fstrans_state_key, fts);
		}
		init_state(fts);
	}
	...
  }

-- 
Juergen Hannken-Illjes - hannken@eis.cs.tu-bs.de - TU Braunschweig (Germany)