12  * to chaining of merge() calls: null-terminated, no reserved or
16 static struct list_head *merge(void *priv, list_cmp_func_t cmp,  in merge()  function
45  * Combine final list merge with restoration of standard doubly-linked
46  * list structure.  This approach duplicates code from merge(), but
83 		 * If the merge is highly unbalanced (e.g. the input is  in merge_final()
144  * for each bit, when count increments to 2^k), we merge two lists of
147  * This merge happens exactly when the count reaches an odd multiple of
149  * so it's safe to merge away two lists of size 2^k.
170  * (merge and loop back to state 2)
174  * merge them away in the 5->2 transition.  Note in particular that just
178  * When we reach the end of the input, we merge all the pending
180  * 5 above, you can see that the number of elements we merge with a list
182  * 2^(k+1) - 1 (second merge of case 5 when x == 2^(k-1) - 1).
208 	 *   That ensures each later final merge will be at worst 2:1.  in list_sort()
221 		/* Do the indicated merge */  in list_sort()
225 			a = merge(priv, cmp, b, a);  in list_sort()
239 	/* End of input; merge together all the pending lists. */  in list_sort()
247 		list = merge(priv, cmp, pending, list);  in list_sort()
250 	/* The final merge, rebuilding prev links */  in list_sort()