Quelle PowerCounters-mac-amd64.cpp Sprache: C

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "PowerCounters.h"
#include "nsDebug.h"
#include "nsPrintfCString.h"
#include "nsXULAppAPI.h"  // for XRE_IsParentProcess

// Because of the pkg_energy_statistics_t::pkes_version check below, the
// earliest OS X version this code will work with is 10.9.0 (xnu-2422.1.72).

#include <sys/types.h>
#include <sys/sysctl.h>

// OS X has four kinds of system calls:
//
//  1. Mach traps;
//  2. UNIX system calls;
//  3. machine-dependent calls;
//  4. diagnostic calls.
//
// (See "Mac OS X and iOS Internals" by Jonathan Levin for more details.)
//
// The last category has a single call named diagCall() or diagCall64(). Its
// mode is controlled by its first argument, and one of the modes allows access
// to the Intel RAPL MSRs.
//
// The interface to diagCall64() is not exported, so we have to import some
// definitions from the XNU kernel. All imported definitions are annotated with
// the XNU source file they come from, and information about what XNU versions
// they were introduced in and (if relevant) modified.

// The diagCall64() mode.
// From osfmk/i386/Diagnostics.h
// - In 10.8.4 (xnu-2050.24.15) this value was introduced. (In 10.8.3 the value
//   17 was used for dgGzallocTest.)
#define dgPowerStat 17

// From osfmk/i386/cpu_data.h
// - In 10.8.5 these values were introduced, along with core_energy_stat_t.
#define CPU_RTIME_BINS (12)
#define CPU_ITIME_BINS (CPU_RTIME_BINS)

// core_energy_stat_t and pkg_energy_statistics_t are both from
// osfmk/i386/Diagnostics.c.
// - In 10.8.4 (xnu-2050.24.15) both structs were introduced, but with many
//   fewer fields.
// - In 10.8.5 (xnu-2050.48.11) both structs were substantially expanded, with
//   numerous new fields.
// - In 10.9.0 (xnu-2422.1.72) pkg_energy_statistics_t::pkes_version was added.
//   diagCall64(dgPowerStat) fills it with '1' in all versions since (up to
//   10.10.2 at time of writing).
// - in 10.10.2 (xnu-2782.10.72) core_energy_stat_t::gpmcs was conditionally
//   added, if DIAG_ALL_PMCS is true. (DIAG_ALL_PMCS is not even defined in the
//   source code, but it could be defined at compile-time via compiler flags.)
//   pkg_energy_statistics_t::pkes_version did not change, though.

typedef struct {
  uint64_t caperf;
  uint64_t cmperf;
  uint64_t ccres[6];
  uint64_t crtimes[CPU_RTIME_BINS];
  uint64_t citimes[CPU_ITIME_BINS];
  uint64_t crtime_total;
  uint64_t citime_total;
  uint64_t cpu_idle_exits;
  uint64_t cpu_insns;
  uint64_t cpu_ucc;
  uint64_t cpu_urc;
#if DIAG_ALL_PMCS           // Added in 10.10.2 (xnu-2782.10.72).
  uint64_t gpmcs[4];        // Added in 10.10.2 (xnu-2782.10.72).
#endif /* DIAG_ALL_PMCS */  // Added in 10.10.2 (xnu-2782.10.72).
} core_energy_stat_t;

typedef struct {
  uint64_t pkes_version;  // Added in 10.9.0 (xnu-2422.1.72).
  uint64_t pkg_cres[2][7];

  // This is read from MSR 0x606, which Intel calls MSR_RAPL_POWER_UNIT
  // and XNU calls MSR_IA32_PKG_POWER_SKU_UNIT.
  uint64_t pkg_power_unit;

  // These are the four fields for the four RAPL domains. For each field
  // we list:
  //
  // - the corresponding MSR number;
  // - Intel's name for that MSR;
  // - XNU's name for that MSR;
  // - which Intel processors the MSR is supported on.
  //
  // The last of these is determined from chapter 35 of Volume 3 of the
  // "Intel 64 and IA-32 Architecture's Software Developer's Manual",
  // Order Number 325384. (Note that chapter 35 contradicts section 14.9
  // to some degree.)

  // 0x611 == MSR_PKG_ENERGY_STATUS == MSR_IA32_PKG_ENERGY_STATUS
  // Atom (various), Sandy Bridge, Next Gen Xeon Phi (model 0x57).
  uint64_t pkg_energy;

  // 0x639 == MSR_PP0_ENERGY_STATUS == MSR_IA32_PP0_ENERGY_STATUS
  // Atom (various), Sandy Bridge, Next Gen Xeon Phi (model 0x57).
  uint64_t pp0_energy;

  // 0x641 == MSR_PP1_ENERGY_STATUS == MSR_PP1_ENERGY_STATUS
  // Sandy Bridge, Haswell.
  uint64_t pp1_energy;

  // 0x619 == MSR_DRAM_ENERGY_STATUS == MSR_IA32_DDR_ENERGY_STATUS
  // Xeon E5, Xeon E5 v2, Haswell/Haswell-E, Next Gen Xeon Phi (model
  // 0x57)
  uint64_t ddr_energy;

  uint64_t llc_flushed_cycles;
  uint64_t ring_ratio_instantaneous;
  uint64_t IA_frequency_clipping_cause;
  uint64_t GT_frequency_clipping_cause;
  uint64_t pkg_idle_exits;
  uint64_t pkg_rtimes[CPU_RTIME_BINS];
  uint64_t pkg_itimes[CPU_ITIME_BINS];
  uint64_t mbus_delay_time;
  uint64_t mint_delay_time;
  uint32_t ncpus;
  core_energy_stat_t cest[];
} pkg_energy_statistics_t;

static int diagCall64(uint64_t aMode, void* aBuf) {
  // We cannot use syscall() here because it doesn't work with diagnostic
  // system calls -- it raises SIGSYS if you try. So we have to use asm.

#ifdef __x86_64__
  // The 0x40000 prefix indicates it's a diagnostic system call. The 0x01
  // suffix indicates the syscall number is 1, which also happens to be the
  // only diagnostic system call. See osfmk/mach/i386/syscall_sw.h for more
  // details.
  static const uint64_t diagCallNum = 0x4000001;
  uint64_t rv;

  __asm__ __volatile__(
      "syscall"

      // Return value goes in "a" (%rax).
      : /* outputs */ "=a"(rv)

      // The syscall number goes in "0", a synonym (from outputs) for "a"
      // (%rax). The syscall arguments go in "D" (%rdi) and "S" (%rsi).
      : /* inputs */ "0"(diagCallNum), "D"(aMode), "S"(aBuf)

      // The |syscall| instruction clobbers %rcx, %r11, and %rflags ("cc"). And
      // this particular syscall also writes memory (aBuf).
      : /* clobbers */ "rcx", "r11", "cc", "memory");
  return rv;
#else
#  error Sorry, only x86-64 is supported
#endif
}

// This is a counter to collect power utilization during profiling.
// It cannot be a raw `ProfilerCounter` because we need to manually add/remove
// it while the profiler lock is already held.
class RaplDomain final : public BaseProfilerCount {
public:
  explicit RaplDomain(const char* aLabel, const char* aDescription)
      : BaseProfilerCount(aLabel, "power", aDescription),
        mSample(0),
        mEnergyStatusUnits(0),
        mWrapAroundCount(0),
        mIsSampleNew(false) {}

  CountSample Sample() override {
    CountSample result;

    // To be consistent with the Windows EMI API,
    // return values in picowatt-hour.
    constexpr double NANOJOULES_PER_JOULE = 1'000'000'000;
    constexpr double NANOJOULES_TO_PICOWATTHOUR = 3.6;

    uint64_t ticks = (uint64_t(mWrapAroundCount) << 32) + mSample;
    double joulesPerTick = (double)1 / (1 << mEnergyStatusUnits);
    result.count = static_cast<double>(ticks) * joulesPerTick *
                   NANOJOULES_PER_JOULE / NANOJOULES_TO_PICOWATTHOUR;

    result.number = 0;
    result.isSampleNew = mIsSampleNew;
    mIsSampleNew = false;
    return result;
  }

  void AddSample(uint32_t aSample, uint32_t aEnergyStatusUnits) {
    if (aSample == mSample) {
      return;
    }

    mEnergyStatusUnits = aEnergyStatusUnits;

    if (aSample > mSample) {
      mIsSampleNew = true;
      mSample = aSample;
      return;
    }

    // Despite being returned in uint64_t fields, the power counter values
    // only use the lowest 32 bits of their fields, and we need to handle
    // wraparounds to avoid our power tracks stopping after a few hours.
    constexpr uint32_t highestBit = 1 << 31;
    if ((mSample & highestBit) && !(aSample & highestBit)) {
      mIsSampleNew = true;
      ++mWrapAroundCount;
      mSample = aSample;
    } else {
      NS_WARNING("unexpected sample with smaller value");
    }
  }

private:
  uint32_t mSample;
  uint32_t mEnergyStatusUnits;
  uint32_t mWrapAroundCount;
  bool mIsSampleNew;
};

class RAPL {
  bool mIsGpuSupported;  // Is the GPU domain supported by the processor?
  bool mIsRamSupported;  // Is the RAM domain supported by the processor?

  // The DRAM domain on Haswell servers has a fixed energy unit (1/65536 J ==
  // 15.3 microJoules) which is different to the power unit MSR. (See the
  // "Intel Xeon Processor E5-1600 and E5-2600 v3 Product Families, Volume 2 of
  // 2, Registers" datasheet, September 2014, Reference Number: 330784-001.)
  // This field records whether the quirk is present.
  bool mHasRamUnitsQuirk;

  // The abovementioned 15.3 microJoules value. (2^16 = 65536)
  static constexpr double kQuirkyRamEnergyStatusUnits = 16;

  // The struct passed to diagCall64().
  pkg_energy_statistics_t* mPkes;

  RaplDomain* mPkg = nullptr;
  RaplDomain* mCores = nullptr;
  RaplDomain* mGpu = nullptr;
  RaplDomain* mRam = nullptr;

public:
  explicit RAPL(PowerCounters::CountVector& aCounters)
      : mHasRamUnitsQuirk(false) {
    // Work out which RAPL MSRs this CPU model supports.
    int cpuModel;
    size_t size = sizeof(cpuModel);
    if (sysctlbyname("machdep.cpu.model", &cpuModel, &size, NULL, 0) != 0) {
      NS_WARNING("sysctlbyname(\"machdep.cpu.model\") failed");
      return;
    }

    // This is similar to arch/x86/kernel/cpu/perf_event_intel_rapl.c in
    // linux-4.1.5/.
    //
    // By linux-5.6.14/, this stuff had moved into
    // arch/x86/events/intel/rapl.c, which references processor families in
    // arch/x86/include/asm/intel-family.h.
    switch (cpuModel) {
      case 0x2a:  // Sandy Bridge
      case 0x3a:  // Ivy Bridge
        // Supports package, cores, GPU.
        mIsGpuSupported = true;
        mIsRamSupported = false;
        break;

      case 0x3f:  // Haswell X
      case 0x4f:  // Broadwell X
      case 0x55:  // Skylake X
      case 0x56:  // Broadwell D
        // Supports package, cores, RAM. Has the units quirk.
        mIsGpuSupported = false;
        mIsRamSupported = true;
        mHasRamUnitsQuirk = true;
        break;

      case 0x2d:  // Sandy Bridge X
      case 0x3e:  // Ivy Bridge X
        // Supports package, cores, RAM.
        mIsGpuSupported = false;
        mIsRamSupported = true;
        break;

      case 0x3c:  // Haswell
      case 0x3d:  // Broadwell
      case 0x45:  // Haswell L
      case 0x46:  // Haswell G
      case 0x47:  // Broadwell G
        // Supports package, cores, GPU, RAM.
        mIsGpuSupported = true;
        mIsRamSupported = true;
        break;

      case 0x4e:  // Skylake L
      case 0x5e:  // Skylake
      case 0x8e:  // Kaby Lake L
      case 0x9e:  // Kaby Lake
      case 0x66:  // Cannon Lake L
      case 0x7d:  // Ice Lake
      case 0x7e:  // Ice Lake L
      case 0xa5:  // Comet Lake
      case 0xa6:  // Comet Lake L
        // Supports package, cores, GPU, RAM, PSYS.
        // XXX: this tool currently doesn't measure PSYS.
        mIsGpuSupported = true;
        mIsRamSupported = true;
        break;

      default:
        NS_WARNING(nsPrintfCString("unknown CPU model: %d", cpuModel).get());
        return;
    }

    // Get the maximum number of logical CPUs so that we know how big to make
    // |mPkes|.
    int logicalcpu_max;
    size = sizeof(logicalcpu_max);
    if (sysctlbyname("hw.logicalcpu_max", &logicalcpu_max, &size, NULL, 0) !=
        0) {
      NS_WARNING("sysctlbyname(\"hw.logicalcpu_max\") failed");
      return;
    }

    // Over-allocate by 1024 bytes per CPU to allow for the uncertainty around
    // core_energy_stat_t::gpmcs and for any other future extensions to that
    // struct. (The fields we read all come before the core_energy_stat_t
    // array, so it won't matter to us whether gpmcs is present or not.)
    size_t pkesSize = sizeof(pkg_energy_statistics_t) +
                      logicalcpu_max * sizeof(core_energy_stat_t) +
                      logicalcpu_max * 1024;
    mPkes = (pkg_energy_statistics_t*)malloc(pkesSize);
    if (mPkes && aCounters.reserve(4)) {
      mPkg = new RaplDomain("Power: CPU package", "RAPL PKG");
      aCounters.infallibleAppend(mPkg);

      mCores = new RaplDomain("Power: CPU cores", "RAPL PP0");
      aCounters.infallibleAppend(mCores);

      if (mIsGpuSupported) {
        mGpu = new RaplDomain("Power: iGPU", "RAPL PP1");
        aCounters.infallibleAppend(mGpu);
      }

      if (mIsRamSupported) {
        mRam = new RaplDomain("Power: DRAM", "RAPL DRAM");
        aCounters.infallibleAppend(mRam);
      }
    }
  }

  ~RAPL() {
    free(mPkes);
    mPkes = nullptr;
  }

  void Sample() {
    constexpr uint64_t kSupportedVersion = 1;

    // If we failed to allocate the memory for package energy statistics, we
    // have nothing to sample.
    if (MOZ_UNLIKELY(!mPkes)) {
      return;
    }

    // Write an unsupported version number into pkes_version so that the check
    // below cannot succeed by dumb luck.
    mPkes->pkes_version = kSupportedVersion - 1;

    // diagCall64() returns 1 on success, and 0 on failure (which can only
    // happen if the mode is unrecognized, e.g. in 10.7.x or earlier versions).
    if (diagCall64(dgPowerStat, mPkes) != 1) {
      NS_WARNING("diagCall64() failed");
      return;
    }

    if (mPkes->pkes_version != kSupportedVersion) {
      NS_WARNING(
          nsPrintfCString("unexpected pkes_version: %llu", mPkes->pkes_version)
              .get());
      return;
    }

    // Bits 12:8 are the ESU.
    // Energy measurements come in multiples of 1/(2^ESU).
    uint32_t energyStatusUnits = (mPkes->pkg_power_unit >> 8) & 0x1f;
    mPkg->AddSample(mPkes->pkg_energy, energyStatusUnits);
    mCores->AddSample(mPkes->pp0_energy, energyStatusUnits);
    if (mIsGpuSupported) {
      mGpu->AddSample(mPkes->pp1_energy, energyStatusUnits);
    }
    if (mIsRamSupported) {
      mRam->AddSample(mPkes->ddr_energy, mHasRamUnitsQuirk
                                             ? kQuirkyRamEnergyStatusUnits
                                             : energyStatusUnits);
    }
  }
};

PowerCounters::PowerCounters() {
  // RAPL values are global, so only sample them on the parent.
  if (XRE_IsParentProcess()) {
    mRapl = mozilla::MakeUnique<RAPL>(mCounters);
  }
}

// This default destructor can not be defined in the header file as it depends
// on the full definition of RAPL which lives in this file.
PowerCounters::~PowerCounters() {}

void PowerCounters::Sample() {
  if (mRapl) {
    mRapl->Sample();
  }
}

quality96%

¤ Dauer der Verarbeitung: 0.7 Sekunden ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.

Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.