Resguardo inicial

linux-7.2.3/tools/perf/check-header_ignore_hunks/lib/list_sort.c

@@ -0,0 +1,24 @@
+@@ -50,6 +50,7 @@
+ 			struct list_head *a, struct list_head *b)
+ {
+ 	struct list_head *tail = head;
++	u8 count = 0;
+ 
+ 	for (;;) {
+ 		/* if equal, take 'a' -- important for sort stability */
+@@ -75,6 +76,15 @@
+ 	/* Finish linking remainder of list b on to tail */
+ 	tail->next = b;
+ 	do {
++		/*
++		 * If the merge is highly unbalanced (e.g. the input is
++		 * already sorted), this loop may run many iterations.
++		 * Continue callbacks to the client even though no
++		 * element comparison is needed, so the client's cmp()
++		 * routine can invoke cond_resched() periodically.
++		 */
++		if (unlikely(!++count))
++			cmp(priv, b, b);
+ 		b->prev = tail;
+ 		tail = b;
+ 		b = b->next;