[PATCH 5/9] sched/psi: don't create cgroup PSI files when psi_disabled

From: Chengming Zhou <zhouchengming@bytedance.com>
To: hannes@cmpxchg.org, surenb@google.com, mingo@redhat.com,
	peterz@infradead.org, tj@kernel.org, corbet@lwn.net,
	akpm@linux-foundation.org, rdunlap@infradead.org
Cc: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
	songmuchun@bytedance.com, cgroups@vger.kernel.org,
	Chengming Zhou <zhouchengming@bytedance.com>
Subject: [PATCH 5/9] sched/psi: don't create cgroup PSI files when psi_disabled
Date: Thu, 21 Jul 2022 12:04:35 +0800	[thread overview]
Message-ID: <20220721040439.2651-6-zhouchengming@bytedance.com> (raw)
In-Reply-To: <20220721040439.2651-1-zhouchengming@bytedance.com>

commit 3958e2d0c34e ("cgroup: make per-cgroup pressure stall tracking configurable")
make PSI can be configured to skip per-cgroup stall accounting. And
doesn't expose PSI files in cgroup hierarchy.

This patch do the same thing when psi_disabled.

Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
---
 kernel/cgroup/cgroup.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 1779ccddb734..1424da7ed2c4 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -3700,6 +3700,9 @@ static void cgroup_pressure_release(struct kernfs_open_file *of)
 
 bool cgroup_psi_enabled(void)
 {
+	if (static_branch_likely(&psi_disabled))
+		return false;
+
 	return (cgroup_feature_disable_mask & (1 << OPT_FEATURE_PRESSURE)) == 0;
 }
 
-- 
2.36.1

