lkml.org 
[lkml]   [2018]   [Nov]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH tip/core/rcu 08/14] rcu: Trace end of grace period before end of grace period
Date
Currently, rcu_gp_cleanup() traces the end of the old grace period after
the old grace period has officially ended. This might make intuitive
sense, but it also makes for confusing event-trace output because the
"end" trace displays not the old but instead the new grace-period number.
This commit therefore traces the end of an old grace period just before
that grace period officially ends.

Reported-by: Aravinda Prasad <aravinda@linux.vnet.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
---
kernel/rcu/tree.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 429a46fb087a..61bae41b1afe 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -2035,9 +2035,9 @@ static void rcu_gp_cleanup(void)
rnp = rcu_get_root();
raw_spin_lock_irq_rcu_node(rnp); /* GP before ->gp_seq update. */

- /* Declare grace period done. */
- rcu_seq_end(&rcu_state.gp_seq);
+ /* Declare grace period done, trace first to use old GP number. */
trace_rcu_grace_period(rcu_state.name, rcu_state.gp_seq, TPS("end"));
+ rcu_seq_end(&rcu_state.gp_seq);
rcu_state.gp_state = RCU_GP_IDLE;
/* Check for GP requests since above loop. */
rdp = this_cpu_ptr(&rcu_data);
--
2.17.1
\
 
 \ /
  Last update: 2018-11-11 20:30    [W:0.253 / U:0.028 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site