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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/oprofile/cpu_buffer.h
Initial import
Diffstat (limited to 'drivers/oprofile/cpu_buffer.h')
-rw-r--r--drivers/oprofile/cpu_buffer.h121
1 files changed, 121 insertions, 0 deletions
diff --git a/drivers/oprofile/cpu_buffer.h b/drivers/oprofile/cpu_buffer.h
new file mode 100644
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+++ b/drivers/oprofile/cpu_buffer.h
@@ -0,0 +1,121 @@
+/**
+ * @file cpu_buffer.h
+ *
+ * @remark Copyright 2002-2009 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon <levon@movementarian.org>
+ * @author Robert Richter <robert.richter@amd.com>
+ */
+
+#ifndef OPROFILE_CPU_BUFFER_H
+#define OPROFILE_CPU_BUFFER_H
+
+#include <linux/types.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+#include <linux/cache.h>
+#include <linux/sched.h>
+#include <linux/ring_buffer.h>
+
+struct task_struct;
+
+int alloc_cpu_buffers(void);
+void free_cpu_buffers(void);
+
+void start_cpu_work(void);
+void end_cpu_work(void);
+void flush_cpu_work(void);
+
+/* CPU buffer is composed of such entries (which are
+ * also used for context switch notes)
+ */
+struct op_sample {
+ unsigned long eip;
+ unsigned long event;
+ unsigned long data[0];
+};
+
+struct op_entry;
+
+struct oprofile_cpu_buffer {
+ unsigned long buffer_size;
+ struct task_struct *last_task;
+ int last_is_kernel;
+ int tracing;
+ unsigned long sample_received;
+ unsigned long sample_lost_overflow;
+ unsigned long backtrace_aborted;
+ unsigned long sample_invalid_eip;
+ int cpu;
+ struct delayed_work work;
+};
+
+DECLARE_PER_CPU(struct oprofile_cpu_buffer, op_cpu_buffer);
+
+/*
+ * 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 op_cpu_buffer_reset(int cpu)
+{
+ struct oprofile_cpu_buffer *cpu_buf = &per_cpu(op_cpu_buffer, cpu);
+
+ cpu_buf->last_is_kernel = -1;
+ cpu_buf->last_task = NULL;
+}
+
+/*
+ * op_cpu_buffer_add_data() and op_cpu_buffer_write_commit() may be
+ * called only if op_cpu_buffer_write_reserve() did not return NULL or
+ * entry->event != NULL, otherwise entry->size or entry->event will be
+ * used uninitialized.
+ */
+
+struct op_sample
+*op_cpu_buffer_write_reserve(struct op_entry *entry, unsigned long size);
+int op_cpu_buffer_write_commit(struct op_entry *entry);
+struct op_sample *op_cpu_buffer_read_entry(struct op_entry *entry, int cpu);
+unsigned long op_cpu_buffer_entries(int cpu);
+
+/* returns the remaining free size of data in the entry */
+static inline
+int op_cpu_buffer_add_data(struct op_entry *entry, unsigned long val)
+{
+ if (!entry->size)
+ return 0;
+ *entry->data = val;
+ entry->size--;
+ entry->data++;
+ return entry->size;
+}
+
+/* returns the size of data in the entry */
+static inline
+int op_cpu_buffer_get_size(struct op_entry *entry)
+{
+ return entry->size;
+}
+
+/* returns 0 if empty or the size of data including the current value */
+static inline
+int op_cpu_buffer_get_data(struct op_entry *entry, unsigned long *val)
+{
+ int size = entry->size;
+ if (!size)
+ return 0;
+ *val = *entry->data;
+ entry->size--;
+ entry->data++;
+ return size;
+}
+
+/* extra data flags */
+#define KERNEL_CTX_SWITCH (1UL << 0)
+#define IS_KERNEL (1UL << 1)
+#define TRACE_BEGIN (1UL << 2)
+#define USER_CTX_SWITCH (1UL << 3)
+
+#endif /* OPROFILE_CPU_BUFFER_H */