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/drivers/xen/sys-hypervisor.c b/drivers/xen/sys-hypervisor.c
index 96453f8..b5a7342 100644
--- a/drivers/xen/sys-hypervisor.c
+++ b/drivers/xen/sys-hypervisor.c
@@ -20,6 +20,9 @@
#include <xen/xenbus.h>
#include <xen/interface/xen.h>
#include <xen/interface/version.h>
+#ifdef CONFIG_XEN_HAVE_VPMU
+#include <xen/interface/xenpmu.h>
+#endif
#define HYPERVISOR_ATTR_RO(_name) \
static struct hyp_sysfs_attr _name##_attr = __ATTR_RO(_name)
@@ -368,6 +371,126 @@
sysfs_remove_group(hypervisor_kobj, &xen_properties_group);
}
+#ifdef CONFIG_XEN_HAVE_VPMU
+struct pmu_mode {
+ const char *name;
+ uint32_t mode;
+};
+
+static struct pmu_mode pmu_modes[] = {
+ {"off", XENPMU_MODE_OFF},
+ {"self", XENPMU_MODE_SELF},
+ {"hv", XENPMU_MODE_HV},
+ {"all", XENPMU_MODE_ALL}
+};
+
+static ssize_t pmu_mode_store(struct hyp_sysfs_attr *attr,
+ const char *buffer, size_t len)
+{
+ int ret;
+ struct xen_pmu_params xp;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(pmu_modes); i++) {
+ if (strncmp(buffer, pmu_modes[i].name, len - 1) == 0) {
+ xp.val = pmu_modes[i].mode;
+ break;
+ }
+ }
+
+ if (i == ARRAY_SIZE(pmu_modes))
+ return -EINVAL;
+
+ xp.version.maj = XENPMU_VER_MAJ;
+ xp.version.min = XENPMU_VER_MIN;
+ ret = HYPERVISOR_xenpmu_op(XENPMU_mode_set, &xp);
+ if (ret)
+ return ret;
+
+ return len;
+}
+
+static ssize_t pmu_mode_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+ int ret;
+ struct xen_pmu_params xp;
+ int i;
+ uint32_t mode;
+
+ xp.version.maj = XENPMU_VER_MAJ;
+ xp.version.min = XENPMU_VER_MIN;
+ ret = HYPERVISOR_xenpmu_op(XENPMU_mode_get, &xp);
+ if (ret)
+ return ret;
+
+ mode = (uint32_t)xp.val;
+ for (i = 0; i < ARRAY_SIZE(pmu_modes); i++) {
+ if (mode == pmu_modes[i].mode)
+ return sprintf(buffer, "%s\n", pmu_modes[i].name);
+ }
+
+ return -EINVAL;
+}
+HYPERVISOR_ATTR_RW(pmu_mode);
+
+static ssize_t pmu_features_store(struct hyp_sysfs_attr *attr,
+ const char *buffer, size_t len)
+{
+ int ret;
+ uint32_t features;
+ struct xen_pmu_params xp;
+
+ ret = kstrtou32(buffer, 0, &features);
+ if (ret)
+ return ret;
+
+ xp.val = features;
+ xp.version.maj = XENPMU_VER_MAJ;
+ xp.version.min = XENPMU_VER_MIN;
+ ret = HYPERVISOR_xenpmu_op(XENPMU_feature_set, &xp);
+ if (ret)
+ return ret;
+
+ return len;
+}
+
+static ssize_t pmu_features_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+ int ret;
+ struct xen_pmu_params xp;
+
+ xp.version.maj = XENPMU_VER_MAJ;
+ xp.version.min = XENPMU_VER_MIN;
+ ret = HYPERVISOR_xenpmu_op(XENPMU_feature_get, &xp);
+ if (ret)
+ return ret;
+
+ return sprintf(buffer, "0x%x\n", (uint32_t)xp.val);
+}
+HYPERVISOR_ATTR_RW(pmu_features);
+
+static struct attribute *xen_pmu_attrs[] = {
+ &pmu_mode_attr.attr,
+ &pmu_features_attr.attr,
+ NULL
+};
+
+static const struct attribute_group xen_pmu_group = {
+ .name = "pmu",
+ .attrs = xen_pmu_attrs,
+};
+
+static int __init xen_pmu_init(void)
+{
+ return sysfs_create_group(hypervisor_kobj, &xen_pmu_group);
+}
+
+static void xen_pmu_destroy(void)
+{
+ sysfs_remove_group(hypervisor_kobj, &xen_pmu_group);
+}
+#endif
+
static int __init hyper_sysfs_init(void)
{
int ret;
@@ -390,7 +513,15 @@
ret = xen_properties_init();
if (ret)
goto prop_out;
-
+#ifdef CONFIG_XEN_HAVE_VPMU
+ if (xen_initial_domain()) {
+ ret = xen_pmu_init();
+ if (ret) {
+ xen_properties_destroy();
+ goto prop_out;
+ }
+ }
+#endif
goto out;
prop_out:
@@ -407,6 +538,9 @@
static void __exit hyper_sysfs_exit(void)
{
+#ifdef CONFIG_XEN_HAVE_VPMU
+ xen_pmu_destroy();
+#endif
xen_properties_destroy();
xen_compilation_destroy();
xen_sysfs_uuid_destroy();