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oprofile: moving cpu_buffer_reset() to cpu_buffer.h

This is in preparation for changes in the cpu buffer implementation.

Signed-off-by: Robert Richter <robert.richter@amd.com>
This commit is contained in:
Robert Richter 2008-12-04 16:27:00 +01:00
parent bf589e3296
commit fbc9bf9f0e
3 changed files with 14 additions and 27 deletions

View File

@ -548,6 +548,7 @@ void sync_buffer(int cpu)
/* Remember, only we can modify tail_pos */
cpu_buffer_reset(cpu);
#ifndef CONFIG_OPROFILE_IBS
available = cpu_buffer_entries(cpu_buf);

View File

@ -124,18 +124,6 @@ void end_cpu_work(void)
flush_scheduled_work();
}
/* Resets the cpu buffer to a sane state. */
void cpu_buffer_reset(struct oprofile_cpu_buffer *cpu_buf)
{
/*
* reset these to invalid values; the next sample collected
* will populate the buffer with proper values to initialize
* the buffer
*/
cpu_buf->last_is_kernel = -1;
cpu_buf->last_task = NULL;
}
/* compute number of available slots in cpu_buffer queue */
static unsigned long nr_available_slots(struct oprofile_cpu_buffer const *b)
{

View File

@ -50,7 +50,19 @@ struct oprofile_cpu_buffer {
DECLARE_PER_CPU(struct oprofile_cpu_buffer, cpu_buffer);
void cpu_buffer_reset(struct oprofile_cpu_buffer *cpu_buf);
/*
* Resets the cpu buffer to a sane state.
*
* reset these to invalid values; the next sample collected will
* populate the buffer with proper values to initialize the buffer
*/
static inline void cpu_buffer_reset(int cpu)
{
struct oprofile_cpu_buffer *cpu_buf = &per_cpu(cpu_buffer, cpu);
cpu_buf->last_is_kernel = -1;
cpu_buf->last_task = NULL;
}
static inline
struct op_sample *cpu_buffer_write_entry(struct oprofile_cpu_buffer *cpu_buf)
@ -88,20 +100,6 @@ unsigned long cpu_buffer_entries(struct oprofile_cpu_buffer *b)
unsigned long head = b->head_pos;
unsigned long tail = b->tail_pos;
/*
* Subtle. This resets the persistent last_task
* and in_kernel values used for switching notes.
* BUT, there is a small window between reading
* head_pos, and this call, that means samples
* can appear at the new head position, but not
* be prefixed with the notes for switching
* kernel mode or a task switch. This small hole
* can lead to mis-attribution or samples where
* we don't know if it's in the kernel or not,
* at the start of an event buffer.
*/
cpu_buffer_reset(b);
if (head >= tail)
return head - tail;