diff options
| author | Ingo Molnar <mingo@kernel.org> | 2015-06-02 08:10:14 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-06-02 08:18:34 +0200 |
| commit | 085c789783f5f95c253740d3d0a1659ec5ff32a8 (patch) | |
| tree | fc36f833f64d044483fd9ccf2f575e9477898914 /kernel/events | |
| parent | c46a024ea5eb0165114dbbc8c82c29b7bcf66e71 (diff) | |
| parent | 0868aa22167d93dd974c253d259c3e6fd47a16c8 (diff) | |
Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU changes from Paul E. McKenney:
- Initialization/Kconfig updates: hide most Kconfig options from unsuspecting users.
There's now a single high level configuration option:
*
* RCU Subsystem
*
Make expert-level adjustments to RCU configuration (RCU_EXPERT) [N/y/?] (NEW)
Which if answered in the negative, leaves us with a single interactive
configuration option:
Offload RCU callback processing from boot-selected CPUs (RCU_NOCB_CPU) [N/y/?] (NEW)
All the rest of the RCU options are configured automatically.
- Remove all uses of RCU-protected array indexes: replace the
rcu_[access|dereference]_index_check() APIs with READ_ONCE() and rcu_lockdep_assert().
- RCU CPU-hotplug cleanups.
- Updates to Tiny RCU: a race fix and further code shrinkage.
- RCU torture-testing updates: fixes, speedups, cleanups and
documentation updates.
- Miscellaneous fixes.
- Documentation updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/events')
| -rw-r--r-- | kernel/events/ring_buffer.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index 232f00f273cb..17fcb73c4a50 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -141,7 +141,7 @@ int perf_output_begin(struct perf_output_handle *handle, perf_output_get_handle(handle); do { - tail = ACCESS_ONCE(rb->user_page->data_tail); + tail = READ_ONCE_CTRL(rb->user_page->data_tail); offset = head = local_read(&rb->head); if (!rb->overwrite && unlikely(CIRC_SPACE(head, tail, perf_data_size(rb)) < size)) |