Merge tag 'trace-v5.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt...

Pull tracing ring-buffer fix from Steven Rostedt:
 "The success return value of ring_buffer_resize() is stated to be
  zero and checked that way.

  But it was incorrectly returning the size allocated.

  Also, a fix to a comment"

* tag 'trace-v5.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ring-buffer: Update the description for ring_buffer_wait
  ring-buffer: Return 0 on success from ring_buffer_resize()

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 15bf28b..7f45fd9 100644 (file)
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -793,7 +793,7 @@ static void rb_wake_up_waiters(struct irq_work *work)
  * ring_buffer_wait - wait for input to the ring buffer
  * @buffer: buffer to wait on
  * @cpu: the cpu buffer to wait on
- * @full: wait until a full page is available, if @cpu != RING_BUFFER_ALL_CPUS
+ * @full: wait until the percentage of pages are available, if @cpu != RING_BUFFER_ALL_CPUS
  *
  * If @cpu == RING_BUFFER_ALL_CPUS then the task will wake up as soon
  * as data is added to any of the @buffer's cpu buffers. Otherwise
@@ -1952,18 +1952,18 @@ int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size,
 {
        struct ring_buffer_per_cpu *cpu_buffer;
        unsigned long nr_pages;
-       int cpu, err = 0;
+       int cpu, err;
 
        /*
         * Always succeed at resizing a non-existent buffer:
         */
        if (!buffer)
-               return size;
+               return 0;
 
        /* Make sure the requested buffer exists */
        if (cpu_id != RING_BUFFER_ALL_CPUS &&
            !cpumask_test_cpu(cpu_id, buffer->cpumask))
-               return size;
+               return 0;
 
        nr_pages = DIV_ROUND_UP(size, BUF_PAGE_SIZE);
 
@@ -2119,7 +2119,7 @@ int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size,
        }
 
        mutex_unlock(&buffer->mutex);
-       return size;
+       return 0;
 
  out_err:
        for_each_buffer_cpu(buffer, cpu) {