Commit 534b483a authored Apr 16, 2015 by Sergey Senozhatsky Committed by Linus Torvalds Apr 17, 2015

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



cpumask_next_and() is looking for cpumask_next() in src1 in a loop and
tests if found cpu is also present in src2. remove that loop, perform
cpumask_and() of src1 and src2 first and use that new mask to find
cpumask_next().

Apart from removing while loop, ./bloat-o-meter on x86_64 shows
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-8 (-8)
function                                     old     new   delta
cpumask_next_and                              62      54      -8

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Amir Vadai <amirv@mellanox.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent dfcce791

lib/cpumask.c

+5 −4

Original line number	Diff line number	Diff line
		@@ -37,10 +37,11 @@ EXPORT_SYMBOL(__next_cpu_nr);
		int cpumask_next_and(int n, const struct cpumask *src1p,
		const struct cpumask *src2p)
		{
		while ((n = cpumask_next(n, src1p)) < nr_cpu_ids)
		if (cpumask_test_cpu(n, src2p))
		break;
		return n;
		struct cpumask tmp;

		if (cpumask_and(&tmp, src1p, src2p))
		return cpumask_next(n, &tmp);
		return nr_cpu_ids;
		}
		EXPORT_SYMBOL(cpumask_next_and);