revert "cpumask: don't perform while loop in cpumask_next_and()"

Revert commit 534b483 ("cpumask: don't perform while loop in cpumask_next_and()"). This was a minor optimization, but it puts a `struct cpumask' on the stack, which consumes too much stack space. Sergey Senozhatsky <[email protected]> Reported-by: Peter Zijlstra <[email protected]> Cc: Sergey Senozhatsky <[email protected]> Cc: Tejun Heo <[email protected]> Cc: "David S. Miller" <[email protected]> Cc: Amir Vadai <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
niw · Jun 19, 2015 · 5ca62d6 · 5ca62d6
1 parent 17fda38
commit 5ca62d6
Showing 1 changed file with 4 additions and 5 deletions.
diff --git a/lib/cpumask.c b/lib/cpumask.c
@@ -16,11 +16,10 @@
 int cpumask_next_and(int n, const struct cpumask *src1p,
 		     const struct cpumask *src2p)
 {
-	struct cpumask tmp;
-
-	if (cpumask_and(&tmp, src1p, src2p))
-		return cpumask_next(n, &tmp);
-	return nr_cpu_ids;
+	while ((n = cpumask_next(n, src1p)) < nr_cpu_ids)
+		if (cpumask_test_cpu(n, src2p))
+			break;
+	return n;
 }
 EXPORT_SYMBOL(cpumask_next_and);