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From:   Kristen Carlson Accardi <kristen@linux.intel.com>
To:     jarkko@kernel.org, dave.hansen@linux.kernel.org, tj@kernel.org,
        linux-kernel@vger.kernel.org, linux-sgx@vger.kernel.org,
        cgroups@vger.kernel.org
Cc:     zhiquan1.li@intel.com,
        Kristen Carlson Accardi <kristen@linux.intel.com>
Subject: [PATCH 23/26] cgroup/misc: Add tryget functionality for misc controller
Date:   Fri, 11 Nov 2022 10:35:28 -0800
Message-Id: <20221111183532.3676646-24-kristen@linux.intel.com>
In-Reply-To: <20221111183532.3676646-1-kristen@linux.intel.com>
References: <20221111183532.3676646-1-kristen@linux.intel.com>
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Allows caller to do a css_tryget() on a specific misc cgroup.

Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>
---
 include/linux/misc_cgroup.h | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/include/linux/misc_cgroup.h b/include/linux/misc_cgroup.h
index 7fbf3efb0f62..cee848205715 100644
--- a/include/linux/misc_cgroup.h
+++ b/include/linux/misc_cgroup.h
@@ -112,6 +112,16 @@ static inline void put_misc_cg(struct misc_cg *cg)
 		css_put(&cg->css);
 }
 
+/*
+ * misc_cg_tryget() - Try to increment this misc cgroup ref count.
+ * @cg - cgroup to get.
+ */
+static inline bool misc_cg_tryget(struct misc_cg *cg)
+{
+	if (cg)
+		return css_tryget(&cg->css);
+	return false;
+}
 #else /* !CONFIG_CGROUP_MISC */
 static inline struct misc_cg *root_misc(void)
 {
@@ -175,6 +185,11 @@ static inline void put_misc_cg(struct misc_cg *cg)
 {
 }
 
+static inline bool misc_cg_tryget(struct misc_cg *cg)
+{
+	return true;
+}
+
 static inline int register_misc_cg_notifier(struct notifier_block *nb)
 {
 	return 0;
-- 
2.37.3