diff options
| author | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2018-01-31 19:23:24 -0800 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2018-02-20 16:12:27 -0800 |
| commit | 9a414201ae7ea089699a0cbd36533345ca17233b (patch) | |
| tree | 90c0c64e89136a0cc09df8cdf06eb8cffa9a6a58 /kernel/rcu/rcu.h | |
| parent | 274afd6bfa64984724963204b832cc71565a7740 (diff) | |
rcu: Add more tracing of expedited grace periods
This commit adds more tracing of expedited grace periods to enable
improved debugging of slowdowns.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'kernel/rcu/rcu.h')
| -rw-r--r-- | kernel/rcu/rcu.h | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h index 5d13f651cf08..507a0802c717 100644 --- a/kernel/rcu/rcu.h +++ b/kernel/rcu/rcu.h @@ -77,12 +77,18 @@ static inline void rcu_seq_start(unsigned long *sp) WARN_ON_ONCE(rcu_seq_state(*sp) != 1); } +/* Compute the end-of-grace-period value for the specified sequence number. */ +static inline unsigned long rcu_seq_endval(unsigned long *sp) +{ + return (*sp | RCU_SEQ_STATE_MASK) + 1; +} + /* Adjust sequence number for end of update-side operation. */ static inline void rcu_seq_end(unsigned long *sp) { smp_mb(); /* Ensure update-side operation before counter increment. */ WARN_ON_ONCE(!rcu_seq_state(*sp)); - WRITE_ONCE(*sp, (*sp | RCU_SEQ_STATE_MASK) + 1); + WRITE_ONCE(*sp, rcu_seq_endval(sp)); } /* Take a snapshot of the update side's sequence number. */ |