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path: root/drivers/oprofile/cpu_buffer.h
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Diffstat (limited to 'drivers/oprofile/cpu_buffer.h')
-rw-r--r--drivers/oprofile/cpu_buffer.h71
1 files changed, 41 insertions, 30 deletions
diff --git a/drivers/oprofile/cpu_buffer.h b/drivers/oprofile/cpu_buffer.h
index 895763f065e..aacb0f0bc56 100644
--- a/drivers/oprofile/cpu_buffer.h
+++ b/drivers/oprofile/cpu_buffer.h
@@ -15,6 +15,7 @@
#include <linux/workqueue.h>
#include <linux/cache.h>
#include <linux/sched.h>
+#include <linux/ring_buffer.h>
struct task_struct;
@@ -32,6 +33,12 @@ struct op_sample {
unsigned long event;
};
+struct op_entry {
+ struct ring_buffer_event *event;
+ struct op_sample *sample;
+ unsigned long irq_flags;
+};
+
struct oprofile_cpu_buffer {
volatile unsigned long head_pos;
volatile unsigned long tail_pos;
@@ -39,7 +46,6 @@ struct oprofile_cpu_buffer {
struct task_struct *last_task;
int last_is_kernel;
int tracing;
- struct op_sample *buffer;
unsigned long sample_received;
unsigned long sample_lost_overflow;
unsigned long backtrace_aborted;
@@ -48,6 +54,8 @@ struct oprofile_cpu_buffer {
struct delayed_work work;
};
+extern struct ring_buffer *op_ring_buffer_read;
+extern struct ring_buffer *op_ring_buffer_write;
DECLARE_PER_CPU(struct oprofile_cpu_buffer, cpu_buffer);
/*
@@ -64,46 +72,49 @@ static inline void cpu_buffer_reset(int cpu)
cpu_buf->last_task = NULL;
}
-static inline
-struct op_sample *cpu_buffer_write_entry(struct oprofile_cpu_buffer *cpu_buf)
+static inline int cpu_buffer_write_entry(struct op_entry *entry)
{
- return &cpu_buf->buffer[cpu_buf->head_pos];
-}
+ entry->event = ring_buffer_lock_reserve(op_ring_buffer_write,
+ sizeof(struct op_sample),
+ &entry->irq_flags);
+ if (entry->event)
+ entry->sample = ring_buffer_event_data(entry->event);
+ else
+ entry->sample = NULL;
-static inline
-void cpu_buffer_write_commit(struct oprofile_cpu_buffer *b)
-{
- unsigned long new_head = b->head_pos + 1;
+ if (!entry->sample)
+ return -ENOMEM;
- /*
- * Ensure anything written to the slot before we increment is
- * visible
- */
- wmb();
+ return 0;
+}
- if (new_head < b->buffer_size)
- b->head_pos = new_head;
- else
- b->head_pos = 0;
+static inline int cpu_buffer_write_commit(struct op_entry *entry)
+{
+ return ring_buffer_unlock_commit(op_ring_buffer_write, entry->event,
+ entry->irq_flags);
}
-static inline
-struct op_sample *cpu_buffer_read_entry(struct oprofile_cpu_buffer *cpu_buf)
+static inline struct op_sample *cpu_buffer_read_entry(int cpu)
{
- return &cpu_buf->buffer[cpu_buf->tail_pos];
+ struct ring_buffer_event *e;
+ e = ring_buffer_consume(op_ring_buffer_read, cpu, NULL);
+ if (e)
+ return ring_buffer_event_data(e);
+ if (ring_buffer_swap_cpu(op_ring_buffer_read,
+ op_ring_buffer_write,
+ cpu))
+ return NULL;
+ e = ring_buffer_consume(op_ring_buffer_read, cpu, NULL);
+ if (e)
+ return ring_buffer_event_data(e);
+ return NULL;
}
/* "acquire" as many cpu buffer slots as we can */
-static inline
-unsigned long cpu_buffer_entries(struct oprofile_cpu_buffer *b)
+static inline unsigned long cpu_buffer_entries(int cpu)
{
- unsigned long head = b->head_pos;
- unsigned long tail = b->tail_pos;
-
- if (head >= tail)
- return head - tail;
-
- return head + (b->buffer_size - tail);
+ return ring_buffer_entries_cpu(op_ring_buffer_read, cpu)
+ + ring_buffer_entries_cpu(op_ring_buffer_write, cpu);
}
/* transient events for the CPU buffer -> event buffer */