xen/PMU: Sysfs interface for setting Xen PMU mode

Set Xen's PMU mode via /sys/hypervisor/pmu/pmu_mode. Add XENPMU hypercall.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
diff --git a/include/xen/interface/xen.h b/include/xen/interface/xen.h
index 8194270..e9d4501 100644
--- a/include/xen/interface/xen.h
+++ b/include/xen/interface/xen.h
@@ -80,6 +80,7 @@
 #define __HYPERVISOR_kexec_op             37
 #define __HYPERVISOR_tmem_op              38
 #define __HYPERVISOR_xc_reserved_op       39 /* reserved for XenClient */
+#define __HYPERVISOR_xenpmu_op            40
 
 /* Architecture-specific hypercall definitions. */
 #define __HYPERVISOR_arch_0               48
diff --git a/include/xen/interface/xenpmu.h b/include/xen/interface/xenpmu.h
new file mode 100644
index 0000000..eac1b49
--- /dev/null
+++ b/include/xen/interface/xenpmu.h
@@ -0,0 +1,59 @@
+#ifndef __XEN_PUBLIC_XENPMU_H__
+#define __XEN_PUBLIC_XENPMU_H__
+
+#include "xen.h"
+
+#define XENPMU_VER_MAJ    0
+#define XENPMU_VER_MIN    1
+
+/*
+ * ` enum neg_errnoval
+ * ` HYPERVISOR_xenpmu_op(enum xenpmu_op cmd, struct xenpmu_params *args);
+ *
+ * @cmd  == XENPMU_* (PMU operation)
+ * @args == struct xenpmu_params
+ */
+/* ` enum xenpmu_op { */
+#define XENPMU_mode_get        0 /* Also used for getting PMU version */
+#define XENPMU_mode_set        1
+#define XENPMU_feature_get     2
+#define XENPMU_feature_set     3
+#define XENPMU_init            4
+#define XENPMU_finish          5
+
+/* ` } */
+
+/* Parameters structure for HYPERVISOR_xenpmu_op call */
+struct xen_pmu_params {
+	/* IN/OUT parameters */
+	struct {
+		uint32_t maj;
+		uint32_t min;
+	} version;
+	uint64_t val;
+
+	/* IN parameters */
+	uint32_t vcpu;
+	uint32_t pad;
+};
+
+/* PMU modes:
+ * - XENPMU_MODE_OFF:   No PMU virtualization
+ * - XENPMU_MODE_SELF:  Guests can profile themselves
+ * - XENPMU_MODE_HV:    Guests can profile themselves, dom0 profiles
+ *                      itself and Xen
+ * - XENPMU_MODE_ALL:   Only dom0 has access to VPMU and it profiles
+ *                      everyone: itself, the hypervisor and the guests.
+ */
+#define XENPMU_MODE_OFF           0
+#define XENPMU_MODE_SELF          (1<<0)
+#define XENPMU_MODE_HV            (1<<1)
+#define XENPMU_MODE_ALL           (1<<2)
+
+/*
+ * PMU features:
+ * - XENPMU_FEATURE_INTEL_BTS: Intel BTS support (ignored on AMD)
+ */
+#define XENPMU_FEATURE_INTEL_BTS  1
+
+#endif /* __XEN_PUBLIC_XENPMU_H__ */