Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/include/linux/rcu_sync.h b/include/linux/rcu_sync.h
index ece7ed9..0027d4c 100644
--- a/include/linux/rcu_sync.h
+++ b/include/linux/rcu_sync.h
@@ -1,20 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
/*
* RCU-based infrastructure for lightweight reader-writer locking
*
- * 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) 2015, Red Hat, Inc.
*
* Author: Oleg Nesterov <oleg@redhat.com>
@@ -26,62 +13,42 @@
#include <linux/wait.h>
#include <linux/rcupdate.h>
-enum rcu_sync_type { RCU_SYNC, RCU_SCHED_SYNC, RCU_BH_SYNC };
-
/* Structure to mediate between updaters and fastpath-using readers. */
struct rcu_sync {
int gp_state;
int gp_count;
wait_queue_head_t gp_wait;
- int cb_state;
struct rcu_head cb_head;
-
- enum rcu_sync_type gp_type;
};
-extern void rcu_sync_lockdep_assert(struct rcu_sync *);
-
/**
* rcu_sync_is_idle() - Are readers permitted to use their fastpaths?
* @rsp: Pointer to rcu_sync structure to use for synchronization
*
- * Returns true if readers are permitted to use their fastpaths.
- * Must be invoked within an RCU read-side critical section whose
- * flavor matches that of the rcu_sync struture.
+ * Returns true if readers are permitted to use their fastpaths. Must be
+ * invoked within some flavor of RCU read-side critical section.
*/
static inline bool rcu_sync_is_idle(struct rcu_sync *rsp)
{
-#ifdef CONFIG_PROVE_RCU
- rcu_sync_lockdep_assert(rsp);
-#endif
- return !rsp->gp_state; /* GP_IDLE */
+ RCU_LOCKDEP_WARN(!rcu_read_lock_any_held(),
+ "suspicious rcu_sync_is_idle() usage");
+ return !READ_ONCE(rsp->gp_state); /* GP_IDLE */
}
-extern void rcu_sync_init(struct rcu_sync *, enum rcu_sync_type);
+extern void rcu_sync_init(struct rcu_sync *);
extern void rcu_sync_enter_start(struct rcu_sync *);
extern void rcu_sync_enter(struct rcu_sync *);
extern void rcu_sync_exit(struct rcu_sync *);
extern void rcu_sync_dtor(struct rcu_sync *);
-#define __RCU_SYNC_INITIALIZER(name, type) { \
+#define __RCU_SYNC_INITIALIZER(name) { \
.gp_state = 0, \
.gp_count = 0, \
.gp_wait = __WAIT_QUEUE_HEAD_INITIALIZER(name.gp_wait), \
- .cb_state = 0, \
- .gp_type = type, \
}
-#define __DEFINE_RCU_SYNC(name, type) \
- struct rcu_sync_struct name = __RCU_SYNC_INITIALIZER(name, type)
-
-#define DEFINE_RCU_SYNC(name) \
- __DEFINE_RCU_SYNC(name, RCU_SYNC)
-
-#define DEFINE_RCU_SCHED_SYNC(name) \
- __DEFINE_RCU_SYNC(name, RCU_SCHED_SYNC)
-
-#define DEFINE_RCU_BH_SYNC(name) \
- __DEFINE_RCU_SYNC(name, RCU_BH_SYNC)
+#define DEFINE_RCU_SYNC(name) \
+ struct rcu_sync name = __RCU_SYNC_INITIALIZER(name)
#endif /* _LINUX_RCU_SYNC_H_ */