# Copyright (c) 2018 Cisco and/or its affiliates.
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at:
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

"""DUT setup library."""

from robot.api import logger

from resources.libraries.python.topology import NodeType, Topology
from resources.libraries.python.ssh import SSH
from resources.libraries.python.constants import Constants
from resources.libraries.python.VatExecutor import VatExecutor
from resources.libraries.python.VPPUtil import VPPUtil


class DUTSetup(object):
    """Contains methods for setting up DUTs."""

    @staticmethod
    def get_service_logs(node, service):
        """Get specific service unit logs by journalctl from node.

        :param node: Node in the topology.
        :param service: Service unit name.
        :type node: dict
        :type service: str
        """
        ssh = SSH()
        ssh.connect(node)
        ret_code, _, _ = \
            ssh.exec_command_sudo('journalctl --no-pager --unit={name} '
                                  '--since="$(echo `systemctl show -p '
                                  'ActiveEnterTimestamp {name}` | '
                                  'awk \'{{print $2 $3}}\')"'.
                                  format(name=service))
        if int(ret_code):
            raise RuntimeError('DUT {host} failed to get logs from unit {name}'.
                               format(host=node['host'], name=service))

    @staticmethod
    def get_service_logs_on_all_duts(nodes, service):
        """Get specific service unit logs by journalctl from all DUTs.

        :param nodes: Nodes in the topology.
        :param service: Service unit name.
        :type nodes: dict
        :type service: str
        """
        for node in nodes.values():
            if node['type'] == NodeType.DUT:
                DUTSetup.get_service_logs(node, service)

    @staticmethod
    def start_service(node, service):
        """Start up the named service on node.

        :param node: Node in the topology.
        :param service: Service unit name.
        :type node: dict
        :type service: str
        """
        ssh = SSH()
        ssh.connect(node)
        # We are doing restart. With this we do not care if service
        # was running or not.
        ret_code, _, _ = \
            ssh.exec_command_sudo('service {name} restart'.
                                  format(name=service), timeout=120)
        if int(ret_code):
            raise RuntimeError('DUT {host} failed to start service {name}'.
                               format(host=node['host'], name=service))

        DUTSetup.get_service_logs(node, service)

    @staticmethod
    def start_vpp_service_on_all_duts(nodes):
        """Start up the VPP service on all nodes.

        :param nodes: Nodes in the topology.
        :type nodes: dict
        """
        for node in nodes.values():
            if node['type'] == NodeType.DUT:
                DUTSetup.start_service(node, Constants.VPP_UNIT)

    @staticmethod
    def vpp_show_version_verbose(node):
        """Run "show version verbose" CLI command.

        :param node: Node to run command on.
        :type node: dict
        """
        vat = VatExecutor()
        vat.execute_script("show_version_verbose.vat", node, json_out=False)

        try:
            vat.script_should_have_passed()
        except AssertionError:
            raise RuntimeError('Failed to get VPP version on host: {name}'.
                               format(name=node['host']))

    @staticmethod
    def show_vpp_version_on_all_duts(nodes):
        """Show VPP version verbose on all DUTs.

        :param nodes: VPP nodes
        :type nodes: dict
        """
        for node in nodes.values():
            if node['type'] == NodeType.DUT:
                DUTSetup.vpp_show_version_verbose(node)

    @staticmethod
    def vpp_show_interfaces(node):
        """Run "show interface" CLI command.

        :param node: Node to run command on.
        :type node: dict
        """
        vat = VatExecutor()
        vat.execute_script("show_interface.vat", node, json_out=False)

        try:
            vat.script_should_have_passed()
        except AssertionError:
            raise RuntimeError('Failed to get VPP interfaces on host: {name}'.
                               format(name=node['host']))

    @staticmethod
    def vpp_api_trace_save(node):
        """Run "api trace save" CLI command.

        :param node: Node to run command on.
        :type node: dict
        """
        vat = VatExecutor()
        vat.execute_script("api_trace_save.vat", node, json_out=False)

    @staticmethod
    def vpp_api_trace_dump(node):
        """Run "api trace custom-dump" CLI command.

        :param node: Node to run command on.
        :type node: dict
        """
        vat = VatExecutor()
        vat.execute_script("api_trace_dump.vat", node, json_out=False)

    @staticmethod
    def setup_all_duts(nodes):
        """Prepare all DUTs in given topology for test execution."""
        for node in nodes.values():
            if node['type'] == NodeType.DUT:
                DUTSetup.setup_dut(node)

    @staticmethod
    def setup_dut(node):
        """Run script over SSH to setup the DUT node.

        :param node: DUT node to set up.
        :type node: dict

        :raises Exception: If the DUT setup fails.
        """
        ssh = SSH()
        ssh.connect(node)

        ret_code, _, _ = \
            ssh.exec_command('sudo -Sn bash {0}/{1}/dut_setup.sh'.
                             format(Constants.REMOTE_FW_DIR,
                                    Constants.RESOURCES_LIB_SH), timeout=120)
        if int(ret_code):
            raise RuntimeError('DUT test setup script failed at node {name}'.
                               format(name=node['host']))

    @staticmethod
    def get_vpp_pid(node):
        """Get PID of running VPP process.

        :param node: DUT node.
        :type node: dict
        :returns: PID
        :rtype: int
        :raises RuntimeError: If it is not possible to get the PID.
        """

        ssh = SSH()
        ssh.connect(node)

        for i in range(3):
            logger.trace('Try {}: Get VPP PID'.format(i))
            ret_code, stdout, stderr = ssh.exec_command('pidof vpp')

            if int(ret_code):
                raise RuntimeError('Not possible to get PID of VPP process '
                                   'on node: {0}\n {1}'.
                                   format(node['host'], stdout + stderr))

            if len(stdout.splitlines()) == 1:
                return int(stdout)
            elif not stdout.splitlines():
                logger.debug("No VPP PID found on node {0}".
                             format(node['host']))
                continue
            else:
                logger.debug("More then one VPP PID found on node {0}".
                             format(node['host']))
                ret_list = list()
                for line in stdout.splitlines():
                    ret_list.append(int(line))
                return ret_list

        return None

    @staticmethod
    def get_vpp_pids(nodes):
        """Get PID of running VPP process on all DUTs.

        :param nodes: DUT nodes.
        :type nodes: dict
        :returns: PIDs
        :rtype: dict
        """

        pids = dict()
        for node in nodes.values():
            if node['type'] == NodeType.DUT:
                pids[node['host']] = DUTSetup.get_vpp_pid(node)
        return pids

    @staticmethod
    def vpp_show_crypto_device_mapping(node):
        """Run "show crypto device mapping" CLI command.

        :param node: Node to run command on.
        :type node: dict
        """
        vat = VatExecutor()
        vat.execute_script("show_crypto_device_mapping.vat", node,
                           json_out=False)

    @staticmethod
    def crypto_device_verify(node, force_init=False, numvfs=32):
        """Verify if Crypto QAT device virtual functions are initialized on all
        DUTs. If parameter force initialization is set to True, then try to
        initialize or disable QAT.

        :param node: DUT node.
        :param force_init: If True then try to initialize to specific value.
        :param numvfs: Number of VFs to initialize, 0 - disable the VFs.
        :type node: dict
        :type force_init: bool
        :type numvfs: int
        :returns: nothing
        :raises RuntimeError: If QAT is not initialized or failed to initialize.
        """

        ssh = SSH()
        ssh.connect(node)

        cryptodev = Topology.get_cryptodev(node)
        cmd = 'cat /sys/bus/pci/devices/{0}/sriov_numvfs'.\
            format(cryptodev.replace(':', r'\:'))

        # Try to read number of VFs from PCI address of QAT device
        for _ in range(3):
            ret_code, stdout, _ = ssh.exec_command(cmd)
            if not int(ret_code):
                try:
                    sriov_numvfs = int(stdout)
                except ValueError:
                    logger.trace('Reading sriov_numvfs info failed on {0}'.
                                 format(node['host']))
                else:
                    if sriov_numvfs != numvfs:
                        if force_init:
                            # QAT is not initialized and we want to initialize
                            # with numvfs
                            DUTSetup.crypto_device_init(node, numvfs)
                        else:
                            raise RuntimeError('QAT device {0} is not '
                                               'initialized to {1} on host {2}'
                                               .format(cryptodev, numvfs,
                                                       node['host']))
                    break

    @staticmethod
    def crypto_device_init(node, numvfs):
        """Init Crypto QAT device virtual functions on DUT.

        :param node: DUT node.
        :param numvfs: Number of VFs to initialize, 0 - disable the VFs.
        :type node: dict
        :type numvfs: int
        :returns: nothing
        :raises RuntimeError: If failed to stop VPP or QAT failed to initialize.
        """
        cryptodev = Topology.get_cryptodev(node)

        # QAT device must be re-bound to kernel driver before initialization
        driver = 'dh895xcc'
        kernel_module = 'qat_dh895xcc'
        current_driver = DUTSetup.get_pci_dev_driver(
            node, cryptodev.replace(':', r'\:'))

        DUTSetup.kernel_module_verify(node, kernel_module, force_load=True)

        VPPUtil.stop_vpp_service(node)
        if current_driver is not None:
            DUTSetup.pci_driver_unbind(node, cryptodev)
        DUTSetup.pci_driver_bind(node, cryptodev, driver)

        ssh = SSH()
        ssh.connect(node)

        # Initialize QAT VFs
        if numvfs > 0:
            cmd = 'echo "{0}" | tee /sys/bus/pci/devices/{1}/sriov_numvfs'.\
                format(numvfs, cryptodev.replace(':', r'\:'), timeout=180)
            ret_code, _, _ = ssh.exec_command_sudo("sh -c '{0}'".format(cmd))

            if int(ret_code):
                raise RuntimeError('Failed to initialize {0} VFs on QAT device '
                                   ' on host {1}'.format(numvfs, node['host']))

    @staticmethod
    def pci_driver_unbind(node, pci_addr):
        """Unbind PCI device from current driver on node.

        :param node: DUT node.
        :param pci_addr: PCI device address.
        :type node: dict
        :type pci_addr: str
        :returns: nothing
        :raises RuntimeError: If PCI device unbind failed.
        """

        ssh = SSH()
        ssh.connect(node)

        ret_code, _, _ = ssh.exec_command_sudo(
            "sh -c 'echo {0} | tee /sys/bus/pci/devices/{1}/driver/unbind'"
            .format(pci_addr, pci_addr.replace(':', r'\:')), timeout=180)

        if int(ret_code):
            raise RuntimeError('Failed to unbind PCI device {0} from driver on '
                               'host {1}'.format(pci_addr, node['host']))

    @staticmethod
    def pci_driver_bind(node, pci_addr, driver):
        """Bind PCI device to driver on node.

        :param node: DUT node.
        :param pci_addr: PCI device address.
        :param driver: Driver to bind.
        :type node: dict
        :type pci_addr: str
        :type driver: str
        :returns: nothing
        :raises RuntimeError: If PCI device bind failed.
        """

        ssh = SSH()
        ssh.connect(node)

        ret_code, _, _ = ssh.exec_command_sudo(
            "sh -c 'echo {0} | tee /sys/bus/pci/drivers/{1}/bind'".format(
                pci_addr, driver), timeout=180)

        if int(ret_code):
            raise RuntimeError('Failed to bind PCI device {0} to {1} driver on '
                               'host {2}'.format(pci_addr, driver,
                                                 node['host']))

    @staticmethod
    def get_pci_dev_driver(node, pci_addr):
        """Get current PCI device driver on node.

        .. note::
            # lspci -vmmks 0000:00:05.0
            Slot:   00:05.0
            Class:  Ethernet controller
            Vendor: Red Hat, Inc
            Device: Virtio network device
            SVendor:        Red Hat, Inc
            SDevice:        Device 0001
            PhySlot:        5
            Driver: virtio-pci

        :param node: DUT node.
        :param pci_addr: PCI device address.
        :type node: dict
        :type pci_addr: str
        :returns: Driver or None
        :raises RuntimeError: If PCI rescan or lspci command execution failed.
        :raises RuntimeError: If it is not possible to get the interface driver
            information from the node.
        """
        ssh = SSH()
        ssh.connect(node)

        for i in range(3):
            logger.trace('Try number {0}: Get PCI device driver'.format(i))

            cmd = 'lspci -vmmks {0}'.format(pci_addr)
            ret_code, stdout, _ = ssh.exec_command(cmd)
            if int(ret_code):
                raise RuntimeError("'{0}' failed on '{1}'"
                                   .format(cmd, node['host']))

            for line in stdout.splitlines():
                if not line:
                    continue
                name = None
                value = None
                try:
                    name, value = line.split("\t", 1)
                except ValueError:
                    if name == "Driver:":
                        return None
                if name == 'Driver:':
                    return value

            if i < 2:
                logger.trace('Driver for PCI device {} not found, executing '
                             'pci rescan and retrying'.format(pci_addr))
                cmd = 'sh -c "echo 1 > /sys/bus/pci/rescan"'
                ret_code, _, _ = ssh.exec_command_sudo(cmd)
                if int(ret_code) != 0:
                    raise RuntimeError("'{0}' failed on '{1}'"
                                       .format(cmd, node['host']))

        return None

    @staticmethod
    def kernel_module_verify(node, module, force_load=False):
        """Verify if kernel module is loaded on node. If parameter force
        load is set to True, then try to load the modules.

        :param node: Node.
        :param module: Module to verify.
        :param force_load: If True then try to load module.
        :type node: dict
        :type module: str
        :type force_load: bool
        :raises RuntimeError: If module is not loaded or failed to load.
        """
        ssh = SSH()
        ssh.connect(node)

        cmd = 'grep -w {0} /proc/modules'.format(module)
        ret_code, _, _ = ssh.exec_command(cmd)

        if int(ret_code):
            if force_load:
                # Module is not loaded and we want to load it
                DUTSetup.kernel_module_load(node, module)
            else:
                raise RuntimeError('Kernel module {0} is not loaded on host '
                                   '{1}'.format(module, node['host']))

    @staticmethod
    def kernel_module_verify_on_all_duts(nodes, module, force_load=False):
        """Verify if kernel module is loaded on all DUTs. If parameter force
        load is set to True, then try to load the modules.

        :param node: DUT nodes.
        :param module: Module to verify.
        :param force_load: If True then try to load module.
        :type node: dict
        :type module: str
        :type force_load: bool
        """
        for node in nodes.values():
            if node['type'] == NodeType.DUT:
                DUTSetup.kernel_module_verify(node, module, force_load)

    @staticmethod
    def verify_uio_driver_on_all_duts(nodes):
        """Verify if uio driver kernel module is loaded on all DUTs. If module
        is not present it will try to load it.

        :param node: DUT nodes.
        :type node: dict
        """
        for node in nodes.values():
            if node['type'] == NodeType.DUT:
                uio_driver = Topology.get_uio_driver(node)
                DUTSetup.kernel_module_verify(node, uio_driver, force_load=True)

    @staticmethod
    def kernel_module_load(node, module):
        """Load kernel module on node.

        :param node: DUT node.
        :param module: Module to load.
        :type node: dict
        :type module: str
        :returns: nothing
        :raises RuntimeError: If loading failed.
        """

        ssh = SSH()
        ssh.connect(node)

        ret_code, _, _ = ssh.exec_command_sudo("modprobe {0}".format(module))

        if int(ret_code):
            raise RuntimeError('Failed to load {0} kernel module on host {1}'.
                               format(module, node['host']))

    @staticmethod
    def vpp_enable_traces_on_all_duts(nodes):
        """Enable vpp packet traces on all DUTs in the given topology.

        :param nodes: Nodes in the topology.
        :type nodes: dict
        """
        for node in nodes.values():
            if node['type'] == NodeType.DUT:
                DUTSetup.vpp_enable_traces_on_dut(node)

    @staticmethod
    def vpp_enable_traces_on_dut(node):
        """Enable vpp packet traces on the DUT node.

        :param node: DUT node to set up.
        :type node: dict
        """

        vat = VatExecutor()
        vat.execute_script("enable_dpdk_traces.vat", node, json_out=False)
        vat.execute_script("enable_vhost_user_traces.vat", node, json_out=False)
        vat.execute_script("enable_memif_traces.vat", node, json_out=False)

    @staticmethod
    def install_vpp_on_all_duts(nodes, vpp_pkg_dir, vpp_rpm_pkgs, vpp_deb_pkgs):
        """Install VPP on all DUT nodes.

        :param nodes: Nodes in the topology.
        :param vpp_pkg_dir: Path to directory where VPP packages are stored.
        :param vpp_rpm_pkgs: List of VPP rpm packages to be installed.
        :param vpp_deb_pkgs: List of VPP deb packages to be installed.
        :type nodes: dict
        :type vpp_pkg_dir: str
        :type vpp_rpm_pkgs: list
        :type vpp_deb_pkgs: list
        :raises RuntimeError: If failed to remove or install VPP.
        """

        logger.debug("Installing VPP")

        for node in nodes.values():
            if node['type'] == NodeType.DUT:
                logger.debug("Installing VPP on node {0}".format(node['host']))

                ssh = SSH()
                ssh.connect(node)

                cmd = "[[ -f /etc/redhat-release ]]"
                return_code, _, _ = ssh.exec_command(cmd)
                if not int(return_code):
                    # workaroud - uninstall existing vpp installation until
                    # start-testcase script is updated on all virl servers
                    rpm_pkgs_remove = "vpp*"
                    cmd_u = 'yum -y remove "{0}"'.format(rpm_pkgs_remove)
                    r_rcode, _, r_err = ssh.exec_command_sudo(cmd_u, timeout=90)
                    if int(r_rcode):
                        raise RuntimeError('Failed to remove previous VPP'
                                           'installation on host {0}:\n{1}'
                                           .format(node['host'], r_err))

                    rpm_pkgs = "*.rpm ".join(str(vpp_pkg_dir + pkg)
                                             for pkg in vpp_rpm_pkgs) + "*.rpm"
                    cmd_i = "rpm -ivh {0}".format(rpm_pkgs)
                    ret_code, _, err = ssh.exec_command_sudo(cmd_i, timeout=90)
                    if int(ret_code):
                        raise RuntimeError('Failed to install VPP on host {0}:'
                                           '\n{1}'.format(node['host'], err))
                    else:
                        ssh.exec_command_sudo("rpm -qai vpp*")
                        logger.info("VPP installed on node {0}".
                                    format(node['host']))
                else:
                    # workaroud - uninstall existing vpp installation until
                    # start-testcase script is updated on all virl servers
                    deb_pkgs_remove = "vpp*"
                    cmd_u = 'apt-get purge -y "{0}"'.format(deb_pkgs_remove)
                    r_rcode, _, r_err = ssh.exec_command_sudo(cmd_u, timeout=90)
                    if int(r_rcode):
                        raise RuntimeError('Failed to remove previous VPP'
                                           'installation on host {0}:\n{1}'
                                           .format(node['host'], r_err))
                    deb_pkgs = "*.deb ".join(str(vpp_pkg_dir + pkg)
                                             for pkg in vpp_deb_pkgs) + "*.deb"
                    cmd_i = "dpkg -i --force-all {0}".format(deb_pkgs)
                    ret_code, _, err = ssh.exec_command_sudo(cmd_i, timeout=90)
                    if int(ret_code):
                        raise RuntimeError('Failed to install VPP on host {0}:'
                                           '\n{1}'.format(node['host'], err))
                    else:
                        ssh.exec_command_sudo("dpkg -l | grep vpp")
                        logger.info("VPP installed on node {0}".
                                    format(node['host']))

                ssh.disconnect(node)

    @staticmethod
    def verify_vpp_on_all_duts(nodes):
        """Verify that VPP is installed on all DUT nodes.

        :param nodes: Nodes in the topology.
        :type nodes: dict
        """

        logger.debug("Verify VPP on all DUTs")

        DUTSetup.start_vpp_service_on_all_duts(nodes)

        for node in nodes.values():
            if node['type'] == NodeType.DUT:
                DUTSetup.verify_vpp_on_dut(node)

    @staticmethod
    def verify_vpp_on_dut(node):
        """Verify that VPP is installed on DUT node.

        :param node: DUT node.
        :type node: dict
        :raises RuntimeError: If failed to restart VPP, get VPP version
            or get VPP interfaces.
        """

        logger.debug("Verify VPP on node {0}".format(node['host']))

        DUTSetup.vpp_show_version_verbose(node)
        DUTSetup.vpp_show_interfaces(node)

    @staticmethod
    def get_huge_page_size(node):
        """Get default size of huge pages in system.

        :param node: Node in the topology.
        :type node: dict
        :returns: Default size of free huge pages in system.
        :rtype: int
        :raises RuntimeError: If reading failed for three times.
        """
        ssh = SSH()
        ssh.connect(node)

        for _ in range(3):
            ret_code, stdout, _ = ssh.exec_command_sudo(
                "grep Hugepagesize /proc/meminfo | awk '{ print $2 }'")
            if ret_code == 0:
                try:
                    huge_size = int(stdout)
                except ValueError:
                    logger.trace('Reading huge page size information failed')
                else:
                    break
        else:
            raise RuntimeError('Getting huge page size information failed.')
        return huge_size

    @staticmethod
    def get_huge_page_free(node, huge_size):
        """Get number of free huge pages in system.

        :param node: Node in the topology.
        :param huge_size: Size of hugepages.
        :type node: dict
        :type huge_size: int
        :returns: Number of free huge pages in system.
        :rtype: int
        :raises RuntimeError: If reading failed for three times.
        """
        # TODO: add numa aware option
        ssh = SSH()
        ssh.connect(node)

        for _ in range(3):
            ret_code, stdout, _ = ssh.exec_command_sudo(
                'cat /sys/kernel/mm/hugepages/hugepages-{0}kB/free_hugepages'.
                format(huge_size))
            if ret_code == 0:
                try:
                    huge_free = int(stdout)
                except ValueError:
                    logger.trace('Reading free huge pages information failed')
                else:
                    break
        else:
            raise RuntimeError('Getting free huge pages information failed.')
        return huge_free

    @staticmethod
    def get_huge_page_total(node, huge_size):
        """Get total number of huge pages in system.

        :param node: Node in the topology.
        :param huge_size: Size of hugepages.
        :type node: dict
        :type huge_size: int

        :returns: Total number of huge pages in system.
        :rtype: int
        :raises RuntimeError: If reading failed for three times.
        """
        # TODO: add numa aware option
        ssh = SSH()
        ssh.connect(node)

        for _ in range(3):
            ret_code, stdout, _ = ssh.exec_command_sudo(
                'cat /sys/kernel/mm/hugepages/hugepages-{0}kB/nr_hugepages'.
                format(huge_size))
            if ret_code == 0:
                try:
                    huge_total = int(stdout)
                except ValueError:
                    logger.trace('Reading total huge pages information failed')
                else:
                    break
        else:
            raise RuntimeError('Getting total huge pages information failed.')
        return huge_total

    @staticmethod
    def check_huge_page(node, huge_mnt, mem_size, allocate=False):
        """Check if there is enough HugePages in system. If allocate is set to
        true, try to allocate more HugePages.

        :param node: Node in the topology.
        :param huge_mnt: HugePage mount point.
        :param mem_size: Requested memory in MB.
        :param allocate: Whether to allocate more memory if not enough.
        :type node: dict
        :type huge_mnt: str
        :type mem_size: str
        :type allocate: bool

        :raises RuntimeError: Mounting hugetlbfs failed or not enough HugePages
        or increasing map count failed.
        """
        # TODO: split function into smaller parts.
        ssh = SSH()
        ssh.connect(node)

        # Get huge pages information
        huge_size = DUTSetup.get_huge_page_size(node)
        huge_free = DUTSetup.get_huge_page_free(node, huge_size)
        huge_total = DUTSetup.get_huge_page_total(node, huge_size)

        # Check if memory reqested is available on host
        if (mem_size * 1024) > (huge_free * huge_size):
            # If we want to allocate hugepage dynamically
            if allocate:
                mem_needed = (mem_size * 1024) - (huge_free * huge_size)
                huge_to_allocate = ((mem_needed / huge_size) * 2) + huge_total
                max_map_count = huge_to_allocate*4
                # Increase maximum number of memory map areas a process may have
                ret_code, _, _ = ssh.exec_command_sudo(
                    'echo "{0}" | sudo tee /proc/sys/vm/max_map_count'.
                    format(max_map_count))
                if int(ret_code) != 0:
                    raise RuntimeError('Increase map count failed on {host}'.
                                       format(host=node['host']))
                # Increase hugepage count
                ret_code, _, _ = ssh.exec_command_sudo(
                    'echo "{0}" | sudo tee /proc/sys/vm/nr_hugepages'.
                    format(huge_to_allocate))
                if int(ret_code) != 0:
                    raise RuntimeError('Mount huge pages failed on {host}'.
                                       format(host=node['host']))
            # If we do not want to allocate dynamicaly end with error
            else:
                raise RuntimeError('Not enough free huge pages: {0}, {1} MB'.
                                   format(huge_free, huge_free * huge_size))
        # Check if huge pages mount point exist
        has_huge_mnt = False
        ret_code, stdout, _ = ssh.exec_command('cat /proc/mounts')
        if int(ret_code) == 0:
            for line in stdout.splitlines():
                # Try to find something like:
                # none /mnt/huge hugetlbfs rw,relatime,pagesize=2048k 0 0
                mount = line.split()
                if mount[2] == 'hugetlbfs' and mount[1] == huge_mnt:
                    has_huge_mnt = True
                    break
        # If huge page mount point not exist create one
        if not has_huge_mnt:
            ret_code, _, _ = ssh.exec_command_sudo(
                'mkdir -p {mnt}'.format(mnt=huge_mnt))
            if int(ret_code) != 0:
                raise RuntimeError('Create mount dir failed on {host}'.
                                   format(host=node['host']))
            ret_code, _, _ = ssh.exec_command_sudo(
                'mount -t hugetlbfs -o pagesize=2048k none {mnt}'.
                format(mnt=huge_mnt))
            if int(ret_code) != 0:
                raise RuntimeError('Mount huge pages failed on {host}'.
                                   format(host=node['host']))