src/mem/probes/mem_footprint.cc

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#include "mem/probes/mem_footprint.hh"

#include "base/intmath.hh"
#include "params/MemFootprintProbe.hh"

namespace gem5
{

MemFootprintProbe::MemFootprintProbe(const MemFootprintProbeParams &p)
    : BaseMemProbe(p),
      cacheLineSizeLg2(floorLog2(p.system->cacheLineSize())),
      pageSizeLg2(floorLog2(p.page_size)),
      totalCacheLinesInMem(p.system->memSize() / p.system->cacheLineSize()),
      totalPagesInMem(p.system->memSize() / p.page_size),
      cacheLines(),
      cacheLinesAll(),
      pages(),
      pagesAll(),
      system(p.system),
      stats(this)
{
    fatal_if(!isPowerOf2(system->cacheLineSize()),
             "MemFootprintProbe expects cache line size is power of 2.");
    fatal_if(!isPowerOf2(p.page_size),
             "MemFootprintProbe expects page size parameter is power of 2");
}

MemFootprintProbe::MemFootprintProbeStats::MemFootprintProbeStats(
    MemFootprintProbe *parent)
    : statistics::Group(parent),
      ADD_STAT(cacheLine, statistics::units::Count::get(),
               "Memory footprint at cache line granularity"),
      ADD_STAT(cacheLineTotal, statistics::units::Count::get(),
               "Total memory footprint at cache line granularity since "
               "simulation begin"),
      ADD_STAT(page, statistics::units::Count::get(),
               "Memory footprint at page granularity"),
      ADD_STAT(pageTotal, statistics::units::Count::get(),
               "Total memory footprint at page granularity since simulation "
               "begin")
{
    using namespace statistics;
    // clang-format off
    cacheLine.flags(nozero | nonan);
    cacheLineTotal.flags(nozero | nonan);
    page.flags(nozero | nonan);
    pageTotal.flags(nozero | nonan);
    // clang-format on
    registerResetCallback([parent]() { parent->statReset(); });
}

void
MemFootprintProbe::insertAddr(Addr addr, AddrSet *set, uint64_t limit)
{
    set->insert(addr);
    assert(set->size() <= limit);
}

void
MemFootprintProbe::handleRequest(const probing::PacketInfo &pi)
{
    if (!pi.cmd.isRequest() || !system->isMemAddr(pi.addr))
        return;

    const Addr cl_addr = (pi.addr >> cacheLineSizeLg2) << cacheLineSizeLg2;
    const Addr page_addr = (pi.addr >> pageSizeLg2) << pageSizeLg2;
    insertAddr(cl_addr, &cacheLines, totalCacheLinesInMem);
    insertAddr(cl_addr, &cacheLinesAll, totalCacheLinesInMem);
    insertAddr(page_addr, &pages, totalPagesInMem);
    insertAddr(page_addr, &pagesAll, totalPagesInMem);

    assert(cacheLines.size() <= cacheLinesAll.size());
    assert(pages.size() <= pagesAll.size());

    stats.cacheLine = cacheLines.size() << cacheLineSizeLg2;
    stats.cacheLineTotal = cacheLinesAll.size() << cacheLineSizeLg2;
    stats.page = pages.size() << pageSizeLg2;
    stats.pageTotal = pagesAll.size() << pageSizeLg2;
}

void
MemFootprintProbe::statReset()
{
    cacheLines.clear();
    pages.clear();
}

} // namespace gem5