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/* 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
#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, nullptr, nullptr, "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); }
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();
}
}