way_pp.cc

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#include "mem/cache/tags/partitioning_policies/way_pp.hh"
 
#include <algorithm>
 
#include "base/logging.hh"
#include "base/trace.hh"
#include "params/WayPartitioningPolicy.hh"
#include "way_allocation.hh"
 
namespace gem5
{
 
namespace partitioning_policy
{
 
WayPartitioningPolicy::WayPartitioningPolicy
    (const WayPartitioningPolicyParams &params): BasePartitioningPolicy(params)
{
    // get cache associativity and check it is usable for this policy
    const auto cache_assoc = params.cache_associativity;
    assert(cache_assoc > 0);
 
    // iterate over all provided allocations
    for (const auto allocation: params.allocations) {
        const auto alloc_id = allocation->getPartitionId();
 
        // save way allocations in policy
        for (const auto way: allocation->getWays()) {
 
            // check if allocations are valid
            fatal_if(way >= cache_assoc, "Way Partitioning Policy allocation "
                "for PartitionID: %d, Way: %d cannot be fullfiled as cache "
                "associativity is %d", alloc_id, way, cache_assoc);
 
            if (this->partitionIdWays[alloc_id].count(way) == 0) {
                this->partitionIdWays[alloc_id].emplace(way);
            } else {
                // do not add duplicate allocation to policy and warn
                warn("Duplicate Way Partitioning Policy allocation for "
                    "PartitionID: %d, Way: %d",
                    alloc_id, way);
            }
        }
 
        // report allocation of policies
        DPRINTF(PartitionPolicy, "Allocated %d ways in WayPartitioningPolicy "
            "for PartitionID: %d \n", allocation->getWays().size(),
            alloc_id);
    }
}
 
void
WayPartitioningPolicy::filterByPartition(
    std::vector<ReplaceableEntry *> &entries,
    const uint64_t partition_id) const
{
    if (// No entries to filter
        entries.empty() ||
        // This partition_id is not policed
        partitionIdWays.find(partition_id) == partitionIdWays.end()) {
        return;
    } else {
        const auto entries_to_remove = std::remove_if(
            entries.begin(),
            entries.end(),
            [this, partition_id]
            (ReplaceableEntry *entry)
            {
                return partitionIdWays.at(partition_id).find(entry->getWay())
                    == partitionIdWays.at(partition_id).end();
            }
        );
 
        entries.erase(entries_to_remove, entries.end());
    }
}
 
} // namespace partitioning_policy
 
} // namespace gem5