Merge branch 'tip/perf/core-2' of git://git.kernel.org/pub/scm/linux/kernel/git/roste...

Pull minor tracing updates and fixes from Steven Rostedt:
 "It seems that one of my old pull requests have slipped through.

  The changes are contained to just the files that I maintain, and are
  changes from others that I told I would get into this merge window.

  They have already been in linux-next for several weeks, and should be
  well tested."

* 'tip/perf/core-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Remove unnecessary WARN_ONCE's from tracing_buffers_splice_read
  tracing: Remove unneeded checks from the stack tracer
  tracing: Add a resize function to make one buffer equivalent to another buffer

diff --combined kernel/trace/trace.c
index 61e081b,5bc3590..e512567
--- 1/kernel/trace/trace.c
--- 2/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@@ -9,7 -9,7 +9,7 @@@
   *
   * Based on code from the latency_tracer, that is:
   *  Copyright (C) 2004-2006 Ingo Molnar
 - *  Copyright (C) 2004 William Lee Irwin III
 + *  Copyright (C) 2004 Nadia Yvette Chambers
   */
  #include <linux/ring_buffer.h>
  #include <generated/utsrelease.h>
@@@ -3034,6 -3034,31 +3034,31 @@@ static void set_buffer_entries(struct t
                tr->data[cpu]->entries = val;
  }
  
+ /* resize @tr's buffer to the size of @size_tr's entries */
+ static int resize_buffer_duplicate_size(struct trace_array *tr,
+                                       struct trace_array *size_tr, int cpu_id)
+ {
+       int cpu, ret = 0;
+ 
+       if (cpu_id == RING_BUFFER_ALL_CPUS) {
+               for_each_tracing_cpu(cpu) {
+                       ret = ring_buffer_resize(tr->buffer,
+                                       size_tr->data[cpu]->entries, cpu);
+                       if (ret < 0)
+                               break;
+                       tr->data[cpu]->entries = size_tr->data[cpu]->entries;
+               }
+       } else {
+               ret = ring_buffer_resize(tr->buffer,
+                                       size_tr->data[cpu_id]->entries, cpu_id);
+               if (ret == 0)
+                       tr->data[cpu_id]->entries =
+                               size_tr->data[cpu_id]->entries;
+       }
+ 
+       return ret;
+ }
+ 
  static int __tracing_resize_ring_buffer(unsigned long size, int cpu)
  {
        int ret;
@@@ -3058,23 -3083,8 +3083,8 @@@
  
        ret = ring_buffer_resize(max_tr.buffer, size, cpu);
        if (ret < 0) {
-               int r = 0;
- 
-               if (cpu == RING_BUFFER_ALL_CPUS) {
-                       int i;
-                       for_each_tracing_cpu(i) {
-                               r = ring_buffer_resize(global_trace.buffer,
-                                               global_trace.data[i]->entries,
-                                               i);
-                               if (r < 0)
-                                       break;
-                       }
-               } else {
-                       r = ring_buffer_resize(global_trace.buffer,
-                                               global_trace.data[cpu]->entries,
-                                               cpu);
-               }
- 
+               int r = resize_buffer_duplicate_size(&global_trace,
+                                                    &global_trace, cpu);
                if (r < 0) {
                        /*
                         * AARGH! We are left with different
@@@ -3212,17 -3222,11 +3222,11 @@@ static int tracing_set_tracer(const cha
  
        topts = create_trace_option_files(t);
        if (t->use_max_tr) {
-               int cpu;
                /* we need to make per cpu buffer sizes equivalent */
-               for_each_tracing_cpu(cpu) {
-                       ret = ring_buffer_resize(max_tr.buffer,
-                                               global_trace.data[cpu]->entries,
-                                               cpu);
-                       if (ret < 0)
-                               goto out;
-                       max_tr.data[cpu]->entries =
-                                       global_trace.data[cpu]->entries;
-               }
+               ret = resize_buffer_duplicate_size(&max_tr, &global_trace,
+                                                  RING_BUFFER_ALL_CPUS);
+               if (ret < 0)
+                       goto out;
        }
  
        if (t->init) {
@@@ -4271,13 -4275,11 +4275,11 @@@ tracing_buffers_splice_read(struct fil
                return -ENOMEM;
  
        if (*ppos & (PAGE_SIZE - 1)) {
-               WARN_ONCE(1, "Ftrace: previous read must page-align\n");
                ret = -EINVAL;
                goto out;
        }
  
        if (len & (PAGE_SIZE - 1)) {
-               WARN_ONCE(1, "Ftrace: splice_read should page-align\n");
                if (len < PAGE_SIZE) {
                        ret = -EINVAL;
                        goto out;