1 files changed, 90 insertions, 0 deletions
diff --git a/include/linux/freezer.h b/include/linux/freezer.h
new file mode 100644
index 000000000..b30347225
--- /dev/null
+++ b/include/linux/freezer.h
@@ -0,0 +1,90 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Freezer declarations */
+
+#ifndef FREEZER_H_INCLUDED
+#define FREEZER_H_INCLUDED
+
+#include <linux/debug_locks.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/atomic.h>
+#include <linux/jump_label.h>
+
+#ifdef CONFIG_FREEZER
+DECLARE_STATIC_KEY_FALSE(freezer_active);
+
+extern bool pm_freezing;		/* PM freezing in effect */
+extern bool pm_nosig_freezing;		/* PM nosig freezing in effect */
+
+/*
+ * Timeout for stopping processes
+ */
+extern unsigned int freeze_timeout_msecs;
+
+/*
+ * Check if a process has been frozen
+ */
+extern bool frozen(struct task_struct *p);
+
+extern bool freezing_slow_path(struct task_struct *p);
+
+/*
+ * Check if there is a request to freeze a process
+ */
+static inline bool freezing(struct task_struct *p)
+{
+	if (static_branch_unlikely(&freezer_active))
+		return freezing_slow_path(p);
+
+	return false;
+}
+
+/* Takes and releases task alloc lock using task_lock() */
+extern void __thaw_task(struct task_struct *t);
+
+extern bool __refrigerator(bool check_kthr_stop);
+extern int freeze_processes(void);
+extern int freeze_kernel_threads(void);
+extern void thaw_processes(void);
+extern void thaw_kernel_threads(void);
+
+static inline bool try_to_freeze(void)
+{
+	might_sleep();
+	if (likely(!freezing(current)))
+		return false;
+	if (!(current->flags & PF_NOFREEZE))
+		debug_check_no_locks_held();
+	return __refrigerator(false);
+}
+
+extern bool freeze_task(struct task_struct *p);
+extern bool set_freezable(void);
+
+#ifdef CONFIG_CGROUP_FREEZER
+extern bool cgroup_freezing(struct task_struct *task);
+#else /* !CONFIG_CGROUP_FREEZER */
+static inline bool cgroup_freezing(struct task_struct *task)
+{
+	return false;
+}
+#endif /* !CONFIG_CGROUP_FREEZER */
+
+#else /* !CONFIG_FREEZER */
+static inline bool frozen(struct task_struct *p) { return false; }
+static inline bool freezing(struct task_struct *p) { return false; }
+static inline void __thaw_task(struct task_struct *t) {}
+
+static inline bool __refrigerator(bool check_kthr_stop) { return false; }
+static inline int freeze_processes(void) { return -ENOSYS; }
+static inline int freeze_kernel_threads(void) { return -ENOSYS; }
+static inline void thaw_processes(void) {}
+static inline void thaw_kernel_threads(void) {}
+
+static inline bool try_to_freeze(void) { return false; }
+
+static inline void set_freezable(void) {}
+
+#endif /* !CONFIG_FREEZER */
+
+#endif	/* FREEZER_H_INCLUDED */