diff options
| author | Pranith Kumar <bobby.prani@gmail.com> | 2014-08-27 16:43:40 -0400 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2014-08-28 05:59:59 -0700 |
| commit | 11ed7f934cb807f26da09547b5946c2e534d1dac (patch) | |
| tree | b67d674bbc9a0d97547c31b3735c99667a7184c1 /kernel/rcu/tree.h | |
| parent | 52addcf9d6669fa439387610bc65c92fa0980cef (diff) | |
rcu: Make nocb leader kthreads process pending callbacks after spawning
The nocb callbacks generated before the nocb kthreads are spawned are
enqueued in the nocb queue for later processing. Commit fbce7497ee5af ("rcu:
Parallelize and economize NOCB kthread wakeups") introduced nocb leader kthreads
which checked the nocb_leader_wake flag to see if there were any such pending
callbacks. A case was reported in which newly spawned leader kthreads were not
processing the pending callbacks as this flag was not set, which led to a boot
hang.
The following commit ensures that the newly spawned nocb kthreads process the
pending callbacks by allowing the kthreads to run immediately after spawning
instead of waiting. This is done by inverting the logic of nocb_leader_wake
tests to nocb_leader_sleep which allows us to use the default initialization of
this flag to 0 to let the kthreads run.
Reported-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Link: http://www.spinics.net/lists/kernel/msg1802899.html
[ paulmck: Backported to v3.17-rc2. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Amit Shah <amit.shah@redhat.com>
Diffstat (limited to 'kernel/rcu/tree.h')
| -rw-r--r-- | kernel/rcu/tree.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index 71e64c718f75..6a86eb7bac45 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -358,7 +358,7 @@ struct rcu_data { struct rcu_head **nocb_gp_tail; long nocb_gp_count; long nocb_gp_count_lazy; - bool nocb_leader_wake; /* Is the nocb leader thread awake? */ + bool nocb_leader_sleep; /* Is the nocb leader thread asleep? */ struct rcu_data *nocb_next_follower; /* Next follower in wakeup chain. */ |