1 files changed, 72 insertions, 0 deletions
diff --git a/include/asm-x86/ds.h b/include/asm-x86/ds.h
new file mode 100644
index 00000000000..7881368142f
--- /dev/null
+++ b/include/asm-x86/ds.h
@@ -0,0 +1,72 @@
+/*
+ * Debug Store (DS) support
+ *
+ * This provides a low-level interface to the hardware's Debug Store
+ * feature that is used for last branch recording (LBR) and
+ * precise-event based sampling (PEBS).
+ *
+ * Different architectures use a different DS layout/pointer size.
+ * The below functions therefore work on a void*.
+ *
+ *
+ * Since there is no user for PEBS, yet, only LBR (or branch
+ * trace store, BTS) is supported.
+ *
+ *
+ * Copyright (C) 2007 Intel Corporation.
+ * Markus Metzger <markus.t.metzger@intel.com>, Dec 2007
+ */
+
+#ifndef _ASM_X86_DS_H
+#define _ASM_X86_DS_H
+
+#include <linux/types.h>
+#include <linux/init.h>
+
+struct cpuinfo_x86;
+
+
+/* a branch trace record entry
+ *
+ * In order to unify the interface between various processor versions,
+ * we use the below data structure for all processors.
+ */
+enum bts_qualifier {
+	BTS_INVALID = 0,
+	BTS_BRANCH,
+	BTS_TASK_ARRIVES,
+	BTS_TASK_DEPARTS
+};
+
+struct bts_struct {
+	u64 qualifier;
+	union {
+		/* BTS_BRANCH */
+		struct {
+			u64 from_ip;
+			u64 to_ip;
+		} lbr;
+		/* BTS_TASK_ARRIVES or
+		   BTS_TASK_DEPARTS */
+		u64 jiffies;
+	} variant;
+};
+
+/* Overflow handling mechanisms */
+#define DS_O_SIGNAL	1 /* send overflow signal */
+#define DS_O_WRAP	2 /* wrap around */
+
+extern int ds_allocate(void **, size_t);
+extern int ds_free(void **);
+extern int ds_get_bts_size(void *);
+extern int ds_get_bts_end(void *);
+extern int ds_get_bts_index(void *);
+extern int ds_set_overflow(void *, int);
+extern int ds_get_overflow(void *);
+extern int ds_clear(void *);
+extern int ds_read_bts(void *, int, struct bts_struct *);
+extern int ds_write_bts(void *, const struct bts_struct *);
+extern unsigned long ds_debugctl_mask(void);
+extern void __cpuinit ds_init_intel(struct cpuinfo_x86 *c);
+
+#endif /* _ASM_X86_DS_H */