Merge tag 'trace-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux...

[GitHub/exynos8895/android_kernel_samsung_universal8895.git] / kernel / trace / ring_buffer.c

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index ff7027199a9a32ea9281bca4e2049ebbb549dd38..925f629658d64df9ba398482986423560db1d3d3 100644 (file)
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -1689,22 +1689,14 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size,
                        if (!cpu_buffer->nr_pages_to_update)
                                continue;
 
-                       /* The update must run on the CPU that is being updated. */
-                       preempt_disable();
-                       if (cpu == smp_processor_id() || !cpu_online(cpu)) {
+                       /* Can't run something on an offline CPU. */
+                       if (!cpu_online(cpu)) {
                                rb_update_pages(cpu_buffer);
                                cpu_buffer->nr_pages_to_update = 0;
                        } else {
-                               /*
-                                * Can not disable preemption for schedule_work_on()
-                                * on PREEMPT_RT.
-                                */
-                               preempt_enable();
                                schedule_work_on(cpu,
                                                &cpu_buffer->update_pages_work);
-                               preempt_disable();
                        }
-                       preempt_enable();
                }
 
                /* wait for all the updates to complete */
@@ -1742,22 +1734,14 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size,
 
                get_online_cpus();
 
-               preempt_disable();
-               /* The update must run on the CPU that is being updated. */
-               if (cpu_id == smp_processor_id() || !cpu_online(cpu_id))
+               /* Can't run something on an offline CPU. */
+               if (!cpu_online(cpu_id))
                        rb_update_pages(cpu_buffer);
                else {
-                       /*
-                        * Can not disable preemption for schedule_work_on()
-                        * on PREEMPT_RT.
-                        */
-                       preempt_enable();
                        schedule_work_on(cpu_id,
                                         &cpu_buffer->update_pages_work);
                        wait_for_completion(&cpu_buffer->update_done);
-                       preempt_disable();
                }
-               preempt_enable();
 
                cpu_buffer->nr_pages_to_update = 0;
                put_online_cpus();
@@ -3775,7 +3759,7 @@ rb_iter_peek(struct ring_buffer_iter *iter, u64 *ts)
        if (rb_per_cpu_empty(cpu_buffer))
                return NULL;
 
-       if (iter->head >= local_read(&iter->head_page->page->commit)) {
+       if (iter->head >= rb_page_size(iter->head_page)) {
                rb_inc_iter(iter);
                goto again;
        }