diff options
| author | Ingo Molnar <mingo@kernel.org> | 2014-10-30 07:37:37 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2014-10-30 07:37:37 +0100 |
| commit | 21ee24bf5b43ecaeec43a7d5c61edb3cd7f847bf (patch) | |
| tree | f240ce442d7ced99390761d267f37815883827f7 /include | |
| parent | 5631b8fba640a4ab2f8a954f63a603fa34eda96b (diff) | |
| parent | d7e29933969e5ca7c112ce1368a07911f4485dc2 (diff) | |
Merge branch 'urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/urgent
Pull two RCU fixes from Paul E. McKenney:
" - Complete the work of commit dd56af42bd82 (rcu: Eliminate deadlock
between CPU hotplug and expedited grace periods), which was
intended to allow synchronize_sched_expedited() to be safely
used when holding locks acquired by CPU-hotplug notifiers.
This commit makes the put_online_cpus() avoid the deadlock
instead of just handling the get_online_cpus().
- Complete the work of commit 35ce7f29a44a (rcu: Create rcuo
kthreads only for onlined CPUs), which was intended to allow
RCU to avoid allocating unneeded kthreads on systems where the
firmware says that there are more CPUs than are really present.
This commit makes rcu_barrier() aware of the mismatch, so that
it doesn't hang waiting for non-existent CPUs. "
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/trace/events/rcu.h | 18 |
1 files changed, 9 insertions, 9 deletions
diff --git a/include/trace/events/rcu.h b/include/trace/events/rcu.h index 9b56f37148cf..e335e7d8c6c2 100644 --- a/include/trace/events/rcu.h +++ b/include/trace/events/rcu.h @@ -660,18 +660,18 @@ TRACE_EVENT(rcu_torture_read, /* * Tracepoint for _rcu_barrier() execution. The string "s" describes * the _rcu_barrier phase: - * "Begin": rcu_barrier_callback() started. - * "Check": rcu_barrier_callback() checking for piggybacking. - * "EarlyExit": rcu_barrier_callback() piggybacked, thus early exit. - * "Inc1": rcu_barrier_callback() piggyback check counter incremented. - * "Offline": rcu_barrier_callback() found offline CPU - * "OnlineNoCB": rcu_barrier_callback() found online no-CBs CPU. - * "OnlineQ": rcu_barrier_callback() found online CPU with callbacks. - * "OnlineNQ": rcu_barrier_callback() found online CPU, no callbacks. + * "Begin": _rcu_barrier() started. + * "Check": _rcu_barrier() checking for piggybacking. + * "EarlyExit": _rcu_barrier() piggybacked, thus early exit. + * "Inc1": _rcu_barrier() piggyback check counter incremented. + * "OfflineNoCB": _rcu_barrier() found callback on never-online CPU + * "OnlineNoCB": _rcu_barrier() found online no-CBs CPU. + * "OnlineQ": _rcu_barrier() found online CPU with callbacks. + * "OnlineNQ": _rcu_barrier() found online CPU, no callbacks. * "IRQ": An rcu_barrier_callback() callback posted on remote CPU. * "CB": An rcu_barrier_callback() invoked a callback, not the last. * "LastCB": An rcu_barrier_callback() invoked the last callback. - * "Inc2": rcu_barrier_callback() piggyback check counter incremented. + * "Inc2": _rcu_barrier() piggyback check counter incremented. * The "cpu" argument is the CPU or -1 if meaningless, the "cnt" argument * is the count of remaining callbacks, and "done" is the piggybacking count. */ |