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diff --git a/include/linux/srcutiny.h b/include/linux/srcutiny.h
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+/*
+ * Sleepable Read-Copy Update mechanism for mutual exclusion,
+ * tiny variant.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
+ *
+ * Copyright (C) IBM Corporation, 2017
+ *
+ * Author: Paul McKenney <paulmck@us.ibm.com>
+ */
+
+#ifndef _LINUX_SRCU_TINY_H
+#define _LINUX_SRCU_TINY_H
+
+#include <linux/swait.h>
+
+struct srcu_struct {
+ int srcu_lock_nesting[2]; /* srcu_read_lock() nesting depth. */
+ struct swait_queue_head srcu_wq;
+ /* Last srcu_read_unlock() wakes GP. */
+ unsigned long srcu_gp_seq; /* GP seq # for callback tagging. */
+ struct rcu_segcblist srcu_cblist;
+ /* Pending SRCU callbacks. */
+ int srcu_idx; /* Current reader array element. */
+ bool srcu_gp_running; /* GP workqueue running? */
+ bool srcu_gp_waiting; /* GP waiting for readers? */
+ struct work_struct srcu_work; /* For driving grace periods. */
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lockdep_map dep_map;
+#endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
+};
+
+void srcu_drive_gp(struct work_struct *wp);
+
+#define __SRCU_STRUCT_INIT(name) \
+{ \
+ .srcu_wq = __SWAIT_QUEUE_HEAD_INITIALIZER(name.srcu_wq), \
+ .srcu_cblist = RCU_SEGCBLIST_INITIALIZER(name.srcu_cblist), \
+ .srcu_work = __WORK_INITIALIZER(name.srcu_work, srcu_drive_gp), \
+ __SRCU_DEP_MAP_INIT(name) \
+}
+
+/*
+ * This odd _STATIC_ arrangement is needed for API compatibility with
+ * Tree SRCU, which needs some per-CPU data.
+ */
+#define DEFINE_SRCU(name) \
+ struct srcu_struct name = __SRCU_STRUCT_INIT(name)
+#define DEFINE_STATIC_SRCU(name) \
+ static struct srcu_struct name = __SRCU_STRUCT_INIT(name)
+
+void synchronize_srcu(struct srcu_struct *sp);
+
+static inline void synchronize_srcu_expedited(struct srcu_struct *sp)
+{
+ synchronize_srcu(sp);
+}
+
+static inline void srcu_barrier(struct srcu_struct *sp)
+{
+ synchronize_srcu(sp);
+}
+
+static inline unsigned long srcu_batches_completed(struct srcu_struct *sp)
+{
+ return 0;
+}
+
+static inline void srcutorture_get_gp_data(enum rcutorture_type test_type,
+ struct srcu_struct *sp, int *flags,
+ unsigned long *gpnum,
+ unsigned long *completed)
+{
+ if (test_type != SRCU_FLAVOR)
+ return;
+ *flags = 0;
+ *completed = sp->srcu_gp_seq;
+ *gpnum = *completed;
+}
+
+#endif