Retrieving NVM average power budget

Conflicts:
	info/v1/machine.go

Signed-off-by: Maciej "Iwan" Iwanowski <maciej.iwanowski@intel.com>

info/v1/machine.go

@@ -176,6 +176,9 @@ type MachineInfo struct {
 	// Memory capacity and number of DIMMs by memory type
 	MemoryByType map[string]*MemoryInfo `json:"memory_by_type"`
 
+	// Average power budget for NVM devices configured in BIOS.
+	NVMAvgPowerBudget uint `json:"nvm_avg_power_budget"`
+
 	// HugePages on this machine.
 	HugePages []HugePagesInfo `json:"hugepages"`
 

machine/machine_libipmctl.go

@@ -0,0 +1,60 @@
+// +build libipmctl
+
+package machine
+
+// #cgo pkg-config: libipmctl
+// #include <nvm_management.h>
+import "C"
+import (
+	"fmt"
+
+	"k8s.io/klog"
+)
+
+var initializedSuccefully bool
+
+func init() {
+	err := C.nvm_init()
+	initializedSuccefully = err == C.NVM_SUCCESS
+	if !initializedSuccefully {
+		klog.Warningf("libipmctl initialization failed with status %d", err)
+	}
+}
+
+// GetNVMAvgPowerBudget retrieves configured power budget for NVM devices.
+// It uses ipmlibctl to get setting configured in BIOS.
+func GetNVMAvgPowerBudget() (uint, error) {
+	// Fail silently when library cannot be initialized.
+	if !initializedSuccefully {
+		return uint(0), nil
+	}
+	// Get number of devices on the platform
+	// see: https://github.com/intel/ipmctl/blob/v01.00.00.3497/src/os/nvm_api/nvm_management.h#L1478
+	var count C.uint
+	err := C.nvm_get_number_of_devices(&count)
+	if err != C.NVM_SUCCESS {
+		klog.Warningf("Unable to get number of NVM devices. Status code: %d", err)
+		return uint(0), fmt.Errorf("Unable to get number of NVM devices. Status code: %d", err)
+	}
+
+	// Load basic device information for all the devices
+	// to obtain UID of the first one.
+	var devices = make([]C.struct_device_discovery, count)
+	err = C.nvm_get_devices(&devices[0], C.uchar(count))
+	if err != C.NVM_SUCCESS {
+		klog.Warningf("Unable to get all NVM devices. Status code: %d", err)
+		return uint(0), fmt.Errorf("Unable to get all NVM devices. Status code: %d", err)
+	}
+
+	// Power budget is same for all the devices
+	// so we can rely on any of them.
+	var device C.struct_device_details
+	err = C.nvm_get_device_details(&devices[0].uid[0], &device)
+	if err != C.NVM_SUCCESS {
+		uid := C.GoString(&devices[0].uid[0])
+		klog.Warningf("Unable to get details of NVM device %q. Status code: %d", uid, err)
+		return uint(0), fmt.Errorf("Unable to get details of NVM device %q. Status code: %d", uid, err)
+	}
+
+	return uint(device.avg_power_budget), nil
+}

machine/machine_no_libipmctl.go

@@ -0,0 +1,9 @@
+// +build !libipmctl
+
+package machine
+
+// GetNVMAvgPowerBudget retrieves configured power budget for NVM devices.
+// When libipmct is not available zero is returned.
+func GetNVMAvgPowerBudget() (uint, error) {
+	return uint(0), nil
+}