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author | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2013-04-11 10:15:52 -0700 |
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committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2013-06-10 13:45:52 -0700 |
commit | 2439b696cb5303f1eeb6aeebcee19e0056c3dd6e (patch) | |
tree | d3f58ced257743911040a2cff5b03cd82aacc8a7 /kernel/rcutree_plugin.h | |
parent | 7807acdb6b794b3af42dfa1912edd4fba8d0b622 (diff) | |
download | linux-2439b696cb5303f1eeb6aeebcee19e0056c3dd6e.tar.gz linux-2439b696cb5303f1eeb6aeebcee19e0056c3dd6e.tar.bz2 linux-2439b696cb5303f1eeb6aeebcee19e0056c3dd6e.zip |
rcu: Shrink TINY_RCU by moving exit_rcu()
Now that TINY_PREEMPT_RCU is no more, exit_rcu() is always an empty
function. But if TINY_RCU is going to have an empty function, it should
be in include/linux/rcutiny.h, where it does not bloat the kernel.
This commit therefore moves exit_rcu() out of kernel/rcupdate.c to
kernel/rcutree_plugin.h, and places a static inline empty function in
include/linux/rcutiny.h in order to shrink TINY_RCU a bit.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Diffstat (limited to 'kernel/rcutree_plugin.h')
-rw-r--r-- | kernel/rcutree_plugin.h | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index 207844ea0226..de701bbdb624 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -932,6 +932,24 @@ static void __init __rcu_init_preempt(void) rcu_init_one(&rcu_preempt_state, &rcu_preempt_data); } +/* + * Check for a task exiting while in a preemptible-RCU read-side + * critical section, clean up if so. No need to issue warnings, + * as debug_check_no_locks_held() already does this if lockdep + * is enabled. + */ +void exit_rcu(void) +{ + struct task_struct *t = current; + + if (likely(list_empty(¤t->rcu_node_entry))) + return; + t->rcu_read_lock_nesting = 1; + barrier(); + t->rcu_read_unlock_special = RCU_READ_UNLOCK_BLOCKED; + __rcu_read_unlock(); +} + #else /* #ifdef CONFIG_TREE_PREEMPT_RCU */ static struct rcu_state *rcu_state = &rcu_sched_state; @@ -1100,6 +1118,14 @@ static void __init __rcu_init_preempt(void) { } +/* + * Because preemptible RCU does not exist, tasks cannot possibly exit + * while in preemptible RCU read-side critical sections. + */ +void exit_rcu(void) +{ +} + #endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */ #ifdef CONFIG_RCU_BOOST |