Use BUDDY_POOL_AVAIL_FUNC() for fellow_logblk_new()

src/fellow_log.c

@@ -427,6 +427,7 @@ BUDDY_REQS(lbuf_dskpool_mem_s, 1);
 // mem block pool
 BUDDY_POOL(lbuf_mempool, 4);	// XXX 4 good?
 BUDDY_POOL_GET_FUNC(lbuf_mempool, static)
+BUDDY_POOL_AVAIL_FUNC(lbuf_mempool, static)
 // memory for flush_finish
 BUDDY_POOL(lbuf_ffpool, 1);
 BUDDY_POOL_GET_FUNC(lbuf_ffpool, static)
@@ -2218,15 +2219,10 @@ fellow_logblk_new(
 	struct fellow_disk_log_block *logblk;
 	struct buddy_ptr_page e;
 
-	if (wait == 0) {
-		// XXX mempool non waiting?
-		e = buddy_alloc1_ptr_page(lbuf->membuddy, MIN_FELLOW_BITS, 0);
-		if (e.ptr == NULL)
-			return (NULL);
-	}
-	else
-		e = buddy_get_next_ptr_page(
-		    lbuf_mempool_get(lbuf->mempool, lbuf));
+	if (wait == 0 && lbuf_mempool_avail(lbuf->mempool) == 0)
+		return (NULL);
+
+	e = buddy_get_next_ptr_page(lbuf_mempool_get(lbuf->mempool, lbuf));
 
 	AN(e.ptr);
 	//lint -e{587} false positive, definitely -- assertion is true