1 files changed, 67 insertions, 2 deletions

diff --git a/drivers/oprofile/cpu_buffer.h b/drivers/oprofile/cpu_buffer.h
index d3cc26264db5..aacb0f0bc566 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;
@@ -48,9 +54,68 @@ 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);
 
-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 int cpu_buffer_write_entry(struct op_entry *entry)
+{
+        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;
+
+        if (!entry->sample)
+                return -ENOMEM;
+
+        return 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(int cpu)
+{
+        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(int cpu)
+{
+        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 */
 #define CPU_IS_KERNEL 1