Gather the segcblist properties in a common map to avoid spreading
booleans in the structure. And this prepares for the offloaded state to
be mutable on runtime.
Inspired-by: Paul E. McKenney <paul...@kernel.org>
Signed-off-by: Frederic Weisbecker <frede...@kernel.org>
Cc: Paul E. McKenney <paul...@kernel.org>
Cc: Josh Triplett <j...@joshtriplett.org>
Cc: Steven Rostedt <rost...@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoy...@efficios.com>
Cc: Lai Jiangshan <jiangshan...@gmail.com>
Cc: Joel Fernandes <j...@joelfernandes.org>
Cc: Neeraj Upadhyay <neer...@codeaurora.org>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Boqun Feng <boqun.f...@gmail.com>
---
include/linux/rcu_segcblist.h | 6 ++++--
kernel/rcu/rcu_segcblist.c | 6 +++---
kernel/rcu/rcu_segcblist.h | 23 +++++++++++++++++++++--
3 files changed, 28 insertions(+), 7 deletions(-)
diff --git a/include/linux/rcu_segcblist.h b/include/linux/rcu_segcblist.h
index 6c01f09a6456..4714b0263c76 100644
--- a/include/linux/rcu_segcblist.h
+++ b/include/linux/rcu_segcblist.h
@@ -63,6 +63,9 @@ struct rcu_cblist {
#define RCU_NEXT_TAIL 3
#define RCU_CBLIST_NSEGS 4
+#define SEGCBLIST_ENABLED BIT(0)
+#define SEGCBLIST_OFFLOADED BIT(1)
+
struct rcu_segcblist {
struct rcu_head *head;
struct rcu_head **tails[RCU_CBLIST_NSEGS];
@@ -73,8 +76,7 @@ struct rcu_segcblist {
long len;
#endif
long seglen[RCU_CBLIST_NSEGS];
- u8 enabled;
- u8 offloaded;
+ u8 flags;
};
#define RCU_SEGCBLIST_INITIALIZER(n) \
diff --git a/kernel/rcu/rcu_segcblist.c b/kernel/rcu/rcu_segcblist.c
index 5059b6102afe..e374f9c3ec2c 100644
--- a/kernel/rcu/rcu_segcblist.c
+++ b/kernel/rcu/rcu_segcblist.c
@@ -234,7 +234,7 @@ void rcu_segcblist_init(struct rcu_segcblist *rsclp)
rcu_segcblist_set_seglen(rsclp, i, 0);
}
rcu_segcblist_set_len(rsclp, 0);
- rsclp->enabled = 1;
+ rcu_segcblist_set_flags(rsclp, SEGCBLIST_ENABLED);
}
/*
@@ -245,7 +245,7 @@ void rcu_segcblist_disable(struct rcu_segcblist *rsclp)
{
WARN_ON_ONCE(!rcu_segcblist_empty(rsclp));
WARN_ON_ONCE(rcu_segcblist_n_cbs(rsclp));
- rsclp->enabled = 0;
+ rcu_segcblist_clear_flags(rsclp, SEGCBLIST_ENABLED);
}
/*
@@ -254,7 +254,7 @@ void rcu_segcblist_disable(struct rcu_segcblist *rsclp)
*/
void rcu_segcblist_offload(struct rcu_segcblist *rsclp)
{
- rsclp->offloaded = 1;
+ rcu_segcblist_set_flags(rsclp, SEGCBLIST_OFFLOADED);
}
/*
diff --git a/kernel/rcu/rcu_segcblist.h b/kernel/rcu/rcu_segcblist.h
index cd35c9faaf51..3d1195dbf030 100644
--- a/kernel/rcu/rcu_segcblist.h
+++ b/kernel/rcu/rcu_segcblist.h
@@ -50,19 +50,38 @@ static inline long rcu_segcblist_n_cbs(struct rcu_segcblist
*rsclp)
#endif
}
+static inline void rcu_segcblist_set_flags(struct rcu_segcblist *rsclp,
+ int flags)
+{
+ rsclp->flags |= flags;
+}
+
+static inline void rcu_segcblist_clear_flags(struct rcu_segcblist *rsclp,
+ int flags)
+{
+ rsclp->flags &= ~flags;
+}
+
+static inline bool rcu_segcblist_test_flags(struct rcu_segcblist *rsclp,
+ int flags)
+{
+ return READ_ONCE(rsclp->flags) & flags;
+}
+
/*
* Is the specified rcu_segcblist enabled, for example, not corresponding
* to an offline CPU?
*/
static inline bool rcu_segcblist_is_enabled(struct rcu_segcblist *rsclp)
{
- return rsclp->enabled;
+ return rcu_segcblist_test_flags(rsclp, SEGCBLIST_ENABLED);
}
/* Is the specified rcu_segcblist offloaded? */
static inline bool rcu_segcblist_is_offloaded(struct rcu_segcblist *rsclp)
{
- return IS_ENABLED(CONFIG_RCU_NOCB_CPU) && rsclp->offloaded;
+ return IS_ENABLED(CONFIG_RCU_NOCB_CPU) &&
+ rcu_segcblist_test_flags(rsclp, SEGCBLIST_OFFLOADED);
}
/*
--
2.25.1
