/*

* Copyright (C) 2020 Intel Corporation.

* All rights reserved.

*

* Redistribution and use in source and binary forms, with or without

* modification, are permitted provided that the following conditions are met:

* 1. Redistributions of source code must retain the above copyright notice(s),

*    this list of conditions and the following disclaimer.

* 2. Redistributions in binary form must reproduce the above copyright notice(s),

*    this list of conditions and the following disclaimer in the documentation

*    and/or other materials provided with the distribution.

*

* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY EXPRESS

* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF

* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO

* EVENT SHALL THE COPYRIGHT HOLDER(S) BE LIABLE FOR ANY DIRECT, INDIRECT,

* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF

* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE

* OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF

* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

*/

#include <climits>

#include <numa.h>

#include <numaif.h>

#include "dax_kmem_nodes.h"

DaxKmem::DaxKmem()

{

    dax_kmem_nodes = get_dax_kmem_nodes();

}

size_t DaxKmem::get_free_space(void)

{

    size_t sum_of_dax_kmem_free_space = 0;

    long long free_space;

    for(auto const &node: dax_kmem_nodes) {

        numa_node_size64(node, &free_space);

        sum_of_dax_kmem_free_space += free_space;

    }

    return sum_of_dax_kmem_free_space;

}

std::set<int> DaxKmem::get_closest_numa_nodes(int regular_node)

{

    int min_distance = INT_MAX;

    std::set<int> closest_numa_ids;

    for (auto const &node: dax_kmem_nodes) {

        int distance_to_i_node = numa_distance(regular_node, node);

        if (distance_to_i_node < min_distance) {

            min_distance = distance_to_i_node;

            closest_numa_ids.clear();

            closest_numa_ids.insert(node);

        } else if (distance_to_i_node == min_distance) {

            closest_numa_ids.insert(node);

        }

    }

    return closest_numa_ids;

}

std::set<int> DaxKmem::get_dax_kmem_nodes(void)

{

    struct bitmask *cpu_mask = numa_allocate_cpumask();

    std::set<int> dax_kmem_nodes;

    const int MAXNODE_ID = numa_max_node();

    for (int id = 0; id <= MAXNODE_ID; ++id) {

        numa_node_to_cpus(id, cpu_mask);

        // Check if NUMA node exists and if it is NUMA node created from persistent memory

        if (numa_node_size64(id, nullptr) > 0 &&

            numa_bitmask_weight(cpu_mask) == 0) {

            dax_kmem_nodes.insert(id);

        }

    }

    numa_free_cpumask(cpu_mask);

    return dax_kmem_nodes;

}

size_t DaxKmem::size(void)

{

    return dax_kmem_nodes.size();

}

bool DaxKmem::contains(int node)

{

    return (dax_kmem_nodes.find(node) != dax_kmem_nodes.end());

}