From: Lai Jiangshan <[email protected]> Make it global so that it can be used in the future inlined rcu_read_unlock().
Make it exported so that the inlined rcu_read_unlock() can be used in modules. Make it taking a void-argument so that the caller can reduce instructions obtaining the "current" task and it can be used in THUNK later. Cc: "Paul E. McKenney" <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Frederic Weisbecker <[email protected]> Signed-off-by: Lai Jiangshan <[email protected]> --- include/linux/rcupdate.h | 2 ++ kernel/rcu/tree_plugin.h | 7 ++++--- 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index ebe9bfc700bb..328667ae8086 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -68,6 +68,8 @@ static inline bool same_state_synchronize_rcu(unsigned long oldstate1, unsigned #ifdef CONFIG_PREEMPT_RCU +void rcu_read_unlock_special(void); + void __rcu_read_lock(void); void __rcu_read_unlock(void); diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 3dbd5609185e..880b3fef1158 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -104,7 +104,6 @@ static void __init rcu_bootup_announce_oddness(void) static void rcu_report_exp_rnp(struct rcu_node *rnp, bool wake); static bool sync_rcu_exp_done(struct rcu_node *rnp); -static void rcu_read_unlock_special(struct task_struct *t); #define set_rcu_preempt_special(reason) do { \ WRITE_ONCE(current->rcu_read_unlock_special.b.reason, true); \ @@ -427,7 +426,7 @@ void __rcu_read_unlock(void) if (rcu_preempt_read_exit() == 0) { barrier(); // critical-section exit before .s check. if (unlikely(READ_ONCE(t->rcu_read_unlock_special.s))) - rcu_read_unlock_special(t); + rcu_read_unlock_special(); } if (IS_ENABLED(CONFIG_PROVE_LOCKING)) { int rrln = rcu_preempt_depth(); @@ -627,8 +626,9 @@ static void rcu_preempt_deferred_qs_handler(struct irq_work *iwp) * notify RCU core processing or task having blocked during the RCU * read-side critical section. */ -static void rcu_read_unlock_special(struct task_struct *t) +void rcu_read_unlock_special(void) { + struct task_struct *t = current; unsigned long flags; bool irqs_were_disabled; bool preempt_bh_were_disabled = @@ -684,6 +684,7 @@ static void rcu_read_unlock_special(struct task_struct *t) } rcu_preempt_deferred_qs_irqrestore(t, flags); } +EXPORT_SYMBOL_GPL(rcu_read_unlock_special); /* * Check that the list of blocked tasks for the newly completed grace -- 2.19.1.6.gb485710b
