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Diffstat (limited to 'include/linux/rcupdate_wait.h')
-rw-r--r--include/linux/rcupdate_wait.h64
1 files changed, 56 insertions, 8 deletions
diff --git a/include/linux/rcupdate_wait.h b/include/linux/rcupdate_wait.h
index c0578ba23c1a..4c92d4291cce 100644
--- a/include/linux/rcupdate_wait.h
+++ b/include/linux/rcupdate_wait.h
@@ -8,6 +8,7 @@
#include <linux/rcupdate.h>
#include <linux/completion.h>
+#include <linux/sched.h>
/*
* Structure allowing asynchronous waiting on RCU.
@@ -15,20 +16,67 @@
struct rcu_synchronize {
struct rcu_head head;
struct completion completion;
+
+ /* This is for debugging. */
+ struct rcu_gp_oldstate oldstate;
};
void wakeme_after_rcu(struct rcu_head *head);
-void __wait_rcu_gp(bool checktiny, int n, call_rcu_func_t *crcu_array,
+void __wait_rcu_gp(bool checktiny, unsigned int state, int n, call_rcu_func_t *crcu_array,
struct rcu_synchronize *rs_array);
-#define _wait_rcu_gp(checktiny, ...) \
-do { \
- call_rcu_func_t __crcu_array[] = { __VA_ARGS__ }; \
- struct rcu_synchronize __rs_array[ARRAY_SIZE(__crcu_array)]; \
- __wait_rcu_gp(checktiny, ARRAY_SIZE(__crcu_array), \
- __crcu_array, __rs_array); \
+#define _wait_rcu_gp(checktiny, state, ...) \
+do { \
+ call_rcu_func_t __crcu_array[] = { __VA_ARGS__ }; \
+ struct rcu_synchronize __rs_array[ARRAY_SIZE(__crcu_array)]; \
+ __wait_rcu_gp(checktiny, state, ARRAY_SIZE(__crcu_array), __crcu_array, __rs_array); \
} while (0)
-#define wait_rcu_gp(...) _wait_rcu_gp(false, __VA_ARGS__)
+#define wait_rcu_gp(...) _wait_rcu_gp(false, TASK_UNINTERRUPTIBLE, __VA_ARGS__)
+#define wait_rcu_gp_state(state, ...) _wait_rcu_gp(false, state, __VA_ARGS__)
+
+/**
+ * synchronize_rcu_mult - Wait concurrently for multiple grace periods
+ * @...: List of call_rcu() functions for different grace periods to wait on
+ *
+ * This macro waits concurrently for multiple types of RCU grace periods.
+ * For example, synchronize_rcu_mult(call_rcu, call_rcu_tasks) would wait
+ * on concurrent RCU and RCU-tasks grace periods. Waiting on a given SRCU
+ * domain requires you to write a wrapper function for that SRCU domain's
+ * call_srcu() function, with this wrapper supplying the pointer to the
+ * corresponding srcu_struct.
+ *
+ * Note that call_rcu_hurry() should be used instead of call_rcu()
+ * because in kernels built with CONFIG_RCU_LAZY=y the delay between the
+ * invocation of call_rcu() and that of the corresponding RCU callback
+ * can be multiple seconds.
+ *
+ * The first argument tells Tiny RCU's _wait_rcu_gp() not to
+ * bother waiting for RCU. The reason for this is because anywhere
+ * synchronize_rcu_mult() can be called is automatically already a full
+ * grace period.
+ */
+#define synchronize_rcu_mult(...) \
+ _wait_rcu_gp(IS_ENABLED(CONFIG_TINY_RCU), TASK_UNINTERRUPTIBLE, __VA_ARGS__)
+
+static inline void cond_resched_rcu(void)
+{
+#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
+ rcu_read_unlock();
+ cond_resched();
+ rcu_read_lock();
+#endif
+}
+
+// Has the current task blocked within its current RCU read-side
+// critical section?
+static inline bool has_rcu_reader_blocked(void)
+{
+#ifdef CONFIG_PREEMPT_RCU
+ return !list_empty(&current->rcu_node_entry);
+#else
+ return false;
+#endif
+}
#endif /* _LINUX_SCHED_RCUPDATE_WAIT_H */