In Tiny SRCU, __srcu_read_lock() is a trivial function, outweighed by its EXPORT_SYMBOL_GPL(), and on many architectures, its call sequence. This commit therefore moves it to srcutiny.h so that it can be inlined.
Signed-off-by: Paul E. McKenney <[email protected]> --- include/linux/srcutiny.h | 14 ++++++++++++++ kernel/rcu/srcutiny.c | 15 --------------- 2 files changed, 14 insertions(+), 15 deletions(-) diff --git a/include/linux/srcutiny.h b/include/linux/srcutiny.h index b8859179b001..013b1b30a354 100644 --- a/include/linux/srcutiny.h +++ b/include/linux/srcutiny.h @@ -63,6 +63,20 @@ void srcu_drive_gp(struct work_struct *wp); void synchronize_srcu(struct srcu_struct *sp); +/* + * Counts the new reader in the appropriate per-CPU element of the + * srcu_struct. Must be called from process context. + * Returns an index that must be passed to the matching srcu_read_unlock(). + */ +static inline int __srcu_read_lock(struct srcu_struct *sp) +{ + int idx; + + idx = READ_ONCE(sp->srcu_idx); + WRITE_ONCE(sp->srcu_lock_nesting[idx], sp->srcu_lock_nesting[idx] + 1); + return idx; +} + static inline void synchronize_srcu_expedited(struct srcu_struct *sp) { synchronize_srcu(sp); diff --git a/kernel/rcu/srcutiny.c b/kernel/rcu/srcutiny.c index 36e1f82faed1..fe0b16db2aae 100644 --- a/kernel/rcu/srcutiny.c +++ b/kernel/rcu/srcutiny.c @@ -96,21 +96,6 @@ void cleanup_srcu_struct(struct srcu_struct *sp) EXPORT_SYMBOL_GPL(cleanup_srcu_struct); /* - * Counts the new reader in the appropriate per-CPU element of the - * srcu_struct. Must be called from process context. - * Returns an index that must be passed to the matching srcu_read_unlock(). - */ -int __srcu_read_lock(struct srcu_struct *sp) -{ - int idx; - - idx = READ_ONCE(sp->srcu_idx); - WRITE_ONCE(sp->srcu_lock_nesting[idx], sp->srcu_lock_nesting[idx] + 1); - return idx; -} -EXPORT_SYMBOL_GPL(__srcu_read_lock); - -/* * Removes the count for the old reader from the appropriate element of * the srcu_struct. Must be called from process context. */ -- 2.5.2
