diff options
| author | Zqiang <qiang1.zhang@intel.com> | 2022-01-25 03:47:44 +0100 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2022-02-02 02:22:17 +0100 |
| commit | c9515875850fefcc79492c5189fe8431e75ddec5 (patch) | |
| tree | c5dd3fe74246dfa81fb8f08df014b26ee7ba3aad /kernel/rcu/tree_plugin.h | |
| parent | rcu: Don't deboost before reporting expedited quiescent state (diff) | |
| download | linux-c9515875850fefcc79492c5189fe8431e75ddec5.tar.xz linux-c9515875850fefcc79492c5189fe8431e75ddec5.zip | |
rcu: Add per-CPU rcuc task dumps to RCU CPU stall warnings
When the rcutree.use_softirq kernel boot parameter is set to zero, all
RCU_SOFTIRQ processing is carried out by the per-CPU rcuc kthreads.
If these kthreads are being starved, quiescent states will not be
reported, which in turn means that the grace period will not end, which
can in turn trigger RCU CPU stall warnings. This commit therefore dumps
stack traces of stalled CPUs' rcuc kthreads, which can help identify
what is preventing those kthreads from running.
Suggested-by: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Reviewed-by: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Signed-off-by: Zqiang <qiang1.zhang@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'kernel/rcu/tree_plugin.h')
| -rw-r--r-- | kernel/rcu/tree_plugin.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 02ac057ba3f8..8167cab1bffc 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -996,12 +996,15 @@ dump_blkd_tasks(struct rcu_node *rnp, int ncheck) */ static void rcu_cpu_kthread_setup(unsigned int cpu) { + struct rcu_data *rdp = per_cpu_ptr(&rcu_data, cpu); #ifdef CONFIG_RCU_BOOST struct sched_param sp; sp.sched_priority = kthread_prio; sched_setscheduler_nocheck(current, SCHED_FIFO, &sp); #endif /* #ifdef CONFIG_RCU_BOOST */ + + WRITE_ONCE(rdp->rcuc_activity, jiffies); } #ifdef CONFIG_RCU_BOOST |