Merge commit 'tip/tracing/core' into oprofile/core

Conflicts:
	drivers/oprofile/cpu_buffer.c

Signed-off-by: Robert Richter <robert.richter@amd.com>

diff --combined drivers/oprofile/cpu_buffer.c
index de82183,7581dbe..0ac8b06
--- 1/drivers/oprofile/cpu_buffer.c
--- 2/drivers/oprofile/cpu_buffer.c
+++ b/drivers/oprofile/cpu_buffer.c
@@@ -30,7 -30,23 +30,7 @@@
  
  #define OP_BUFFER_FLAGS       0
  
 -/*
 - * Read and write access is using spin locking. Thus, writing to the
 - * buffer by NMI handler (x86) could occur also during critical
 - * sections when reading the buffer. To avoid this, there are 2
 - * buffers for independent read and write access. Read access is in
 - * process context only, write access only in the NMI handler. If the
 - * read buffer runs empty, both buffers are swapped atomically. There
 - * is potentially a small window during swapping where the buffers are
 - * disabled and samples could be lost.
 - *
 - * Using 2 buffers is a little bit overhead, but the solution is clear
 - * and does not require changes in the ring buffer implementation. It
 - * can be changed to a single buffer solution when the ring buffer
 - * access is implemented as non-locking atomic code.
 - */
 -static struct ring_buffer *op_ring_buffer_read;
 -static struct ring_buffer *op_ring_buffer_write;
 +static struct ring_buffer *op_ring_buffer;
  DEFINE_PER_CPU(struct oprofile_cpu_buffer, op_cpu_buffer);
  
  static void wq_sync_buffer(struct work_struct *work);
@@@ -52,9 -68,12 +52,9 @@@ void oprofile_cpu_buffer_inc_smpl_lost(
  
  void free_cpu_buffers(void)
  {
 -      if (op_ring_buffer_read)
 -              ring_buffer_free(op_ring_buffer_read);
 -      op_ring_buffer_read = NULL;
 -      if (op_ring_buffer_write)
 -              ring_buffer_free(op_ring_buffer_write);
 -      op_ring_buffer_write = NULL;
 +      if (op_ring_buffer)
 +              ring_buffer_free(op_ring_buffer);
 +      op_ring_buffer = NULL;
  }
  
  #define RB_EVENT_HDR_SIZE 4
@@@ -67,8 -86,11 +67,8 @@@ int alloc_cpu_buffers(void
        unsigned long byte_size = buffer_size * (sizeof(struct op_sample) +
                                                 RB_EVENT_HDR_SIZE);
  
 -      op_ring_buffer_read = ring_buffer_alloc(byte_size, OP_BUFFER_FLAGS);
 -      if (!op_ring_buffer_read)
 -              goto fail;
 -      op_ring_buffer_write = ring_buffer_alloc(byte_size, OP_BUFFER_FLAGS);
 -      if (!op_ring_buffer_write)
 +      op_ring_buffer = ring_buffer_alloc(byte_size, OP_BUFFER_FLAGS);
 +      if (!op_ring_buffer)
                goto fail;
  
        for_each_possible_cpu(i) {
@@@ -140,11 -162,16 +140,11 @@@ struct op_sampl
  *op_cpu_buffer_write_reserve(struct op_entry *entry, unsigned long size)
  {
        entry->event = ring_buffer_lock_reserve
 -              (op_ring_buffer_write, sizeof(struct op_sample) +
 +              (op_ring_buffer, sizeof(struct op_sample) +
                 size * sizeof(entry->sample->data[0]));
 -      if (entry->event)
 -              entry->sample = ring_buffer_event_data(entry->event);
 -      else
 -              entry->sample = NULL;
 -
 -      if (!entry->sample)
 +      if (!entry->event)
                return NULL;
 -
 +      entry->sample = ring_buffer_event_data(entry->event);
        entry->size = size;
        entry->data = entry->sample->data;
  
@@@ -153,16 -180,25 +153,16 @@@
  
  int op_cpu_buffer_write_commit(struct op_entry *entry)
  {
 -      return ring_buffer_unlock_commit(op_ring_buffer_write, entry->event);
 +      return ring_buffer_unlock_commit(op_ring_buffer, entry->event);
  }
  
  struct op_sample *op_cpu_buffer_read_entry(struct op_entry *entry, int cpu)
  {
        struct ring_buffer_event *e;
-       e = ring_buffer_consume(op_ring_buffer, cpu, NULL);
 -      e = ring_buffer_consume(op_ring_buffer_read, cpu, NULL, NULL);
 -      if (e)
 -              goto event;
 -      if (ring_buffer_swap_cpu(op_ring_buffer_read,
 -                               op_ring_buffer_write,
 -                               cpu))
++      e = ring_buffer_consume(op_ring_buffer, cpu, NULL, NULL);
 +      if (!e)
                return NULL;
 -      e = ring_buffer_consume(op_ring_buffer_read, cpu, NULL, NULL);
 -      if (e)
 -              goto event;
 -      return NULL;
  
 -event:
        entry->event = e;
        entry->sample = ring_buffer_event_data(e);
        entry->size = (ring_buffer_event_length(e) - sizeof(struct op_sample))
@@@ -173,7 -209,8 +173,7 @@@
  
  unsigned long op_cpu_buffer_entries(int cpu)
  {
 -      return ring_buffer_entries_cpu(op_ring_buffer_read, cpu)
 -              + ring_buffer_entries_cpu(op_ring_buffer_write, cpu);
 +      return ring_buffer_entries_cpu(op_ring_buffer, cpu);
  }
  
  static int