diff options
| author | Paul E. McKenney | 2018-07-25 11:49:47 -0700 |
|---|---|---|
| committer | Paul E. McKenney | 2018-08-30 16:03:44 -0700 |
| commit | d3052109c0bc9e536d17d627ae628ed8ceb6928c (patch) | |
| tree | 95d7a83a78bf0d3f1ba62975d7258d1d547038e9 /kernel/rcu/tree.h | |
| parent | c06aed0e31008a248c1841f1b7fc80e9ee242a31 (diff) | |
rcu: More aggressively enlist scheduler aid for nohz_full CPUs
Because nohz_full CPUs can leave the scheduler-clock interrupt disabled
even when in kernel mode, RCU cannot rely on rcu_check_callbacks() to
enlist the scheduler's aid in extracting a quiescent state from such CPUs.
This commit therefore more aggressively uses resched_cpu() on nohz_full
CPUs that fail to pass through a quiescent state in a timely manner.
By default, the resched_cpu() beating starts 300 milliseconds into the
quiescent state.
While in the neighborhood, add a ->last_fqs_resched field to the rcu_data
structure in order to rate-limit resched_cpu() calls from the RCU
grace-period kthread.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'kernel/rcu/tree.h')
| -rw-r--r-- | kernel/rcu/tree.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index 4866fa44ab0b..8f053bb1eec8 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -260,6 +260,7 @@ struct rcu_data { short rcu_ofl_gp_flags; /* ->gp_flags at last offline. */ unsigned long rcu_onl_gp_seq; /* ->gp_seq at last online. */ short rcu_onl_gp_flags; /* ->gp_flags at last online. */ + unsigned long last_fqs_resched; /* Time of last rcu_resched(). */ int cpu; }; |