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	struct frotz {
		...
		struct frotz	*f_next;
	};

	static struct {
		kmutex_t	lock;
		pserialize_t	psz;
		struct frotz	*first;
	} frobbotzim __cacheline_aligned;

	struct frotz *f = pool_get(&frotz_pool, PR_WAITOK);

	/* Initialize f.  */
	...

	mutex_enter(&frobbotzim.lock);
	f->f_next = frobbotzim.first;
	/*
	 * Publish the contents of f->f_next before we publish the
	 * pointer to f in frobbotzim.first.
	 */
	membar_producer();
	frobbotzim.first = f;
	mutex_exit(&frobbotzim.lock);

	struct frotz *f;
	int error = ENOENT;
	int s;

	s = pserialize_read_enter();
	for (f = frobbotzim.first; f != NULL; f = f->f_next) {
		/* Fetch f before we fetch anything f points to.  */
		membar_datadep_consumer();
		if (f->f_... == key) {
			/*
			 * Grab whatever part of the frotz we need.
			 * Note that we can't use the frotz after
			 * pserialize_read_exit, without a stronger
			 * kind of reference, say a reference count
			 * managed by atomic_ops(3).
			 */
			*resultp = f->f_...;
			error = 0;
			break;
		}
	}
	pserialize_read_exit(s);

	return error;

	struct frotz **fp, *f;

	mutex_enter(&frobbotzim.lock);
	for (fp = &frobbotzim.first; (f = *fp) != NULL; fp = &f->f_next) {
		if (f->f_... == key) {
			/*
			 * Unhook it from the list.  Readers may still
			 * be traversing the list at this point, so
			 * the next pointer must remain valid and
			 * memory must remain allocated.
			 */
			*fp = f->f_next;
			break;
		}
	}
	/*
	 * Wait for all existing readers to complete.  New readers will
	 * not see f because the list no longer points to it.
	 */
	pserialize_perform(frobbotzim.psz);
	/* Now nobody else can be touching f, so it is safe to free.  */
	mutex_exit(&frobbotzim.lock);

	if (f != NULL)
		pool_put(&frotz_pool, f);