EnvVars.hpp

/*
Copyright (c) 2021-2023 Advanced Micro Devices, Inc. All rights reserved.

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*/

#ifndef ENVVARS_HPP
#define ENVVARS_HPP

#include <algorithm>
#include <random>
#include <time.h>
#include "Compatibility.hpp"
#include "Kernels.hpp"

#define TB_VERSION "1.23"

extern char const MemTypeStr[];
extern char const ExeTypeStr[];

enum ConfigModeEnum
{
  CFG_FILE  = 0,
  CFG_P2P   = 1,
  CFG_SWEEP = 2,
  CFG_SCALE = 3
};

// This class manages environment variable that affect TransferBench
class EnvVars
{
public:
  // Default configuration values
  int const DEFAULT_NUM_WARMUPS          =  1;
  int const DEFAULT_NUM_ITERATIONS       = 10;
  int const DEFAULT_SAMPLING_FACTOR      =  1;

  // Peer-to-peer Benchmark preset defaults
  int const DEFAULT_P2P_NUM_CPU_SE    = 4;

  // Sweep-preset defaults
  std::string const DEFAULT_SWEEP_SRC = "CG";
  std::string const DEFAULT_SWEEP_EXE = "CDG";
  std::string const DEFAULT_SWEEP_DST = "CG";
  int const DEFAULT_SWEEP_MIN         = 1;
  int const DEFAULT_SWEEP_MAX         = 24;
  int const DEFAULT_SWEEP_TEST_LIMIT  = 0;
  int const DEFAULT_SWEEP_TIME_LIMIT  = 0;

  // Environment variables
  int blockBytes;        // Each CU, except the last, gets a multiple of this many bytes to copy
  int byteOffset;        // Byte-offset for memory allocations
  int continueOnError;   // Continue tests even after mismatch detected
  int numCpuDevices;     // Number of CPU devices to use (defaults to # NUMA nodes detected)
  int numGpuDevices;     // Number of GPU devices to use (defaults to # HIP devices detected)
  int numIterations;     // Number of timed iterations to perform.  If negative, run for -numIterations seconds instead
  int numWarmups;        // Number of un-timed warmup iterations to perform
  int outputToCsv;       // Output in CSV format
  int samplingFactor;    // Affects how many different values of N are generated (when N set to 0)
  int sharedMemBytes;    // Amount of shared memory to use per threadblock
  int useInteractive;    // Pause for user-input before starting transfer loop
  int usePcieIndexing;   // Base GPU indexing on PCIe address instead of HIP device
  int usePrepSrcKernel;  // Use GPU kernel to prepare source data instead of copy (can't be used with fillPattern)
  int useSingleStream;   // Use a single stream per GPU GFX executor instead of stream per Transfer
  int validateDirect;    // Validate GPU destination memory directly instead of staging GPU memory on host

  std::vector<float> fillPattern; // Pattern of floats used to fill source data

  // Environment variables only for Benchmark-preset
  int useRemoteRead;     // Use destination memory type as executor instead of source memory type
  int useDmaCopy;        // Use DMA copy instead of GPU copy
  int numGpuSubExecs;    // Number of GPU subexecutors to use
  int numCpuSubExecs;    // Number of CPU subexecttors to use

  // Environment variables only for Sweep-preset
  int sweepMin;          // Min number of simultaneous Transfers to be executed per test
  int sweepMax;          // Max number of simulatneous Transfers to be executed per test
  int sweepTestLimit;    // Max number of tests to run during sweep (0 = no limit)
  int sweepTimeLimit;    // Max number of seconds to run sweep for  (0 = no limit)
  int sweepXgmiMin;      // Min number of XGMI hops for Transfers
  int sweepXgmiMax;      // Max number of XGMI hops for Transfers (-1 = no limit)
  int sweepSeed;         // Random seed to use
  int sweepRandBytes;    // Whether or not to use random number of bytes per Transfer
  std::string sweepSrc;  // Set of src memory types to be swept
  std::string sweepExe;  // Set of executors to be swept
  std::string sweepDst;  // Set of dst memory types to be swept

  // Developer features
  int enableDebug;       // Enable debug output
  int gpuKernel;         // Which GPU kernel to use

  // Used to track current configuration mode
  ConfigModeEnum configMode;

  // Random generator
  std::default_random_engine *generator;

  // Track how many CPUs are available per NUMA node
  std::vector<int> numCpusPerNuma;

  // Constructor that collects values
  EnvVars()
  {
    int maxSharedMemBytes = 0;
    HIP_CALL(hipDeviceGetAttribute(&maxSharedMemBytes,
                                   hipDeviceAttributeMaxSharedMemoryPerMultiprocessor, 0));
#if !defined(__NVCC__)
    int defaultSharedMemBytes = maxSharedMemBytes / 2 + 1;
#else
    int defaultSharedMemBytes = 0;
#endif

    int numDeviceCUs = 0;
    HIP_CALL(hipDeviceGetAttribute(&numDeviceCUs, hipDeviceAttributeMultiprocessorCount, 0));

    int numDetectedCpus = numa_num_configured_nodes();
    int numDetectedGpus;
    HIP_CALL(hipGetDeviceCount(&numDetectedGpus));

    hipDeviceProp_t prop;
    HIP_CALL(hipGetDeviceProperties(&prop, 0));
    std::string fullName = prop.gcnArchName;
    std::string archName = fullName.substr(0, fullName.find(':'));

    // Different hardware pick different GPU kernels
    // This performance difference is generally only noticable when executing fewer CUs
    int defaultGpuKernel = 0;
    if      (archName == "gfx906") defaultGpuKernel = 13;
    else if (archName == "gfx90a") defaultGpuKernel = 9;

    blockBytes        = GetEnvVar("BLOCK_BYTES"         , 256);
    byteOffset        = GetEnvVar("BYTE_OFFSET"         , 0);
    continueOnError   = GetEnvVar("CONTINUE_ON_ERROR"   , 0);
    numCpuDevices     = GetEnvVar("NUM_CPU_DEVICES"     , numDetectedCpus);
    numGpuDevices     = GetEnvVar("NUM_GPU_DEVICES"     , numDetectedGpus);
    numIterations     = GetEnvVar("NUM_ITERATIONS"      , DEFAULT_NUM_ITERATIONS);
    numWarmups        = GetEnvVar("NUM_WARMUPS"         , DEFAULT_NUM_WARMUPS);
    outputToCsv       = GetEnvVar("OUTPUT_TO_CSV"       , 0);
    samplingFactor    = GetEnvVar("SAMPLING_FACTOR"     , DEFAULT_SAMPLING_FACTOR);
    sharedMemBytes    = GetEnvVar("SHARED_MEM_BYTES"    , defaultSharedMemBytes);
    useInteractive    = GetEnvVar("USE_INTERACTIVE"     , 0);
    usePcieIndexing   = GetEnvVar("USE_PCIE_INDEX"      , 0);
    usePrepSrcKernel  = GetEnvVar("USE_PREP_KERNEL"     , 0);
    useSingleStream   = GetEnvVar("USE_SINGLE_STREAM"   , 0);
    validateDirect    = GetEnvVar("VALIDATE_DIRECT"     , 0);
    enableDebug       = GetEnvVar("DEBUG"               , 0);
    gpuKernel         = GetEnvVar("GPU_KERNEL"          , defaultGpuKernel);

    // P2P Benchmark related
    useRemoteRead    = GetEnvVar("USE_REMOTE_READ"      , 0);
    useDmaCopy       = GetEnvVar("USE_GPU_DMA"          , 0);
    numGpuSubExecs   = GetEnvVar("NUM_GPU_SE"           , useDmaCopy ? 1 : numDeviceCUs);
    numCpuSubExecs   = GetEnvVar("NUM_CPU_SE"           , DEFAULT_P2P_NUM_CPU_SE);

    // Sweep related
    sweepMin          = GetEnvVar("SWEEP_MIN"           , DEFAULT_SWEEP_MIN);
    sweepMax          = GetEnvVar("SWEEP_MAX"           , DEFAULT_SWEEP_MAX);
    sweepSrc          = GetEnvVar("SWEEP_SRC"           , DEFAULT_SWEEP_SRC);
    sweepExe          = GetEnvVar("SWEEP_EXE"           , DEFAULT_SWEEP_EXE);
    sweepDst          = GetEnvVar("SWEEP_DST"           , DEFAULT_SWEEP_DST);
    sweepTestLimit    = GetEnvVar("SWEEP_TEST_LIMIT"    , DEFAULT_SWEEP_TEST_LIMIT);
    sweepTimeLimit    = GetEnvVar("SWEEP_TIME_LIMIT"    , DEFAULT_SWEEP_TIME_LIMIT);
    sweepXgmiMin      = GetEnvVar("SWEEP_XGMI_MIN"      , 0);
    sweepXgmiMax      = GetEnvVar("SWEEP_XGMI_MAX"      , -1);
    sweepRandBytes    = GetEnvVar("SWEEP_RAND_BYTES"    , 0);

    // Determine random seed
    char *sweepSeedStr = getenv("SWEEP_SEED");
    sweepSeed = (sweepSeedStr != NULL ? atoi(sweepSeedStr) : time(NULL));
    generator = new std::default_random_engine(sweepSeed);

    // Check for fill pattern
    char* pattern = getenv("FILL_PATTERN");
    if (pattern != NULL)
    {
      if (usePrepSrcKernel)
      {
        printf("[ERROR] Unable to use FILL_PATTERN and USE_PREP_KERNEL together\n");
        exit(1);
      }

      int patternLen = strlen(pattern);
      if (patternLen % 2)
      {
        printf("[ERROR] FILL_PATTERN must contain an even-number of hex digits\n");
        exit(1);
      }

      // Read in bytes
      std::vector<unsigned char> bytes;
      unsigned char val = 0;
      for (int i = 0; i < patternLen; i++)
      {
        if ('0' <= pattern[i] && pattern[i] <= '9')
          val += (pattern[i] - '0');
        else if ('A' <= pattern[i] && pattern[i] <= 'F')
          val += (pattern[i] - 'A' + 10);
        else if ('a' <= pattern[i] && pattern[i] <= 'f')
          val += (pattern[i] - 'a' + 10);
        else
        {
          printf("[ERROR] FILL_PATTERN must contain an even-number of hex digits (0-9'/a-f/A-F).  (not %c)\n", pattern[i]);
          exit(1);
        }

        if (i % 2 == 0)
          val <<= 4;
        else
        {
          bytes.push_back(val);
          val = 0;
        }
      }

      // Reverse bytes (input is assumed to be given in big-endian)
      std::reverse(bytes.begin(), bytes.end());

      // Figure out how many copies of the pattern are necessary to fill a 4-byte float properly
      int copies;
      switch (patternLen % 8)
      {
      case 0:  copies = 1; break;
      case 4:  copies = 2; break;
      default: copies = 4; break;
      }

      // Fill floats
      int numFloats = copies * patternLen / 8;
      fillPattern.resize(numFloats);
      unsigned char* rawData = (unsigned char*) fillPattern.data();
      for (int i = 0; i < numFloats * 4; i++)
        rawData[i] = bytes[i % bytes.size()];
    }
    else fillPattern.clear();

    // Perform some basic validation
    if (numCpuDevices > numDetectedCpus)
    {
      printf("[ERROR] Number of CPUs to use (%d) cannot exceed number of detected CPUs (%d)\n", numCpuDevices, numDetectedCpus);
      exit(1);
    }
    if (numGpuDevices > numDetectedGpus)
    {
      printf("[ERROR] Number of GPUs to use (%d) cannot exceed number of detected GPUs (%d)\n", numGpuDevices, numDetectedGpus);
      exit(1);
    }
    if (byteOffset % sizeof(float))
    {
      printf("[ERROR] BYTE_OFFSET must be set to multiple of %lu\n", sizeof(float));
      exit(1);
    }
    if (numWarmups < 0)
    {
      printf("[ERROR] NUM_WARMUPS must be set to a non-negative number\n");
      exit(1);
    }
    if (samplingFactor < 1)
    {
      printf("[ERROR] SAMPLING_FACTOR must be greater or equal to 1\n");
      exit(1);
    }
    if (sharedMemBytes < 0 || sharedMemBytes > maxSharedMemBytes)
    {
      printf("[ERROR] SHARED_MEM_BYTES must be between 0 and %d\n", maxSharedMemBytes);
      exit(1);
    }
    if (blockBytes <= 0 || blockBytes % 4)
    {
      printf("[ERROR] BLOCK_BYTES must be a positive multiple of 4\n");
      exit(1);
    }

    if (numGpuSubExecs <= 0)
    {
      printf("[ERROR] NUM_GPU_SE must be greater than 0\n");
      exit(1);
    }

    if (numCpuSubExecs <= 0)
    {
      printf("[ERROR] NUM_CPU_SE must be greater than 0\n");
      exit(1);
    }

    for (auto ch : sweepSrc)
    {
      if (!strchr(MemTypeStr, ch))
      {
        printf("[ERROR] Unrecognized memory type '%c' specified for sweep source\n", ch);
        exit(1);
      }
      if (strchr(sweepSrc.c_str(), ch) != strrchr(sweepSrc.c_str(), ch))
      {
        printf("[ERROR] Duplicate memory type '%c' specified for sweep source\n", ch);
        exit(1);
      }
    }

    for (auto ch : sweepDst)
    {
      if (!strchr(MemTypeStr, ch))
      {
        printf("[ERROR] Unrecognized memory type '%c' specified for sweep destination\n", ch);
        exit(1);
      }
      if (strchr(sweepDst.c_str(), ch) != strrchr(sweepDst.c_str(), ch))
      {
        printf("[ERROR] Duplicate memory type '%c' specified for sweep destination\n", ch);
        exit(1);
      }
    }

    for (auto ch : sweepExe)
    {
      if (!strchr(ExeTypeStr, ch))
      {
        printf("[ERROR] Unrecognized executor type '%c' specified for sweep executor\n", ch);
        exit(1);
      }
      if (strchr(sweepExe.c_str(), ch) != strrchr(sweepExe.c_str(), ch))
      {
        printf("[ERROR] Duplicate executor type '%c' specified for sweep executor\n", ch);
        exit(1);
      }
    }
    if (gpuKernel < 0 || gpuKernel > NUM_GPU_KERNELS)
    {
      printf("[ERROR] GPU kernel must be between 0 and %d\n", NUM_GPU_KERNELS);
      exit(1);
    }

    // Determine how many CPUs exit per NUMA node (to avoid executing on NUMA without CPUs)
    numCpusPerNuma.resize(numDetectedCpus);
    int const totalCpus = numa_num_configured_cpus();
    for (int i = 0; i < totalCpus; i++)
      numCpusPerNuma[numa_node_of_cpu(i)]++;

    // Check for deprecated env vars
    if (getenv("USE_HIP_CALL"))
    {
      printf("[WARN] USE_HIP_CALL has been deprecated.  Please use DMA executor 'D' or set USE_GPU_DMA for P2P-Benchmark preset\n");
      exit(1);
    }

    char* enableSdma = getenv("HSA_ENABLE_SDMA");
    if (enableSdma && !strcmp(enableSdma, "0"))
    {
      printf("[WARN] DMA functionality disabled due to environment variable HSA_ENABLE_SDMA=0.  Copies will fallback to blit kernels\n");
    }
  }

  // Display info on the env vars that can be used
  static void DisplayUsage()
  {
    printf("Environment variables:\n");
    printf("======================\n");
    printf(" BLOCK_BYTES=B          - Each CU (except the last) receives a multiple of BLOCK_BYTES to copy\n");
    printf(" BYTE_OFFSET            - Initial byte-offset for memory allocations.  Must be multiple of 4. Defaults to 0\n");
    printf(" CONTINUE_ON_ERROR      - Continue tests even after mismatch detected\n");
    printf(" FILL_PATTERN=STR       - Fill input buffer with pattern specified in hex digits (0-9,a-f,A-F).  Must be even number of digits, (byte-level big-endian)\n");
    printf(" NUM_CPU_DEVICES=X      - Restrict number of CPUs to X.  May not be greater than # detected NUMA nodes\n");
    printf(" NUM_GPU_DEVICES=X      - Restrict number of GPUs to X.  May not be greater than # detected HIP devices\n");
    printf(" NUM_ITERATIONS=I       - Perform I timed iteration(s) per test\n");
    printf(" NUM_WARMUPS=W          - Perform W untimed warmup iteration(s) per test\n");
    printf(" OUTPUT_TO_CSV          - Outputs to CSV format if set\n");
    printf(" SAMPLING_FACTOR=F      - Add F samples (when possible) between powers of 2 when auto-generating data sizes\n");
    printf(" SHARED_MEM_BYTES=X     - Use X shared mem bytes per threadblock, potentially to avoid multiple threadblocks per CU\n");
    printf(" USE_INTERACTIVE        - Pause for user-input before starting transfer loop\n");
    printf(" USE_PCIE_INDEX         - Index GPUs by PCIe address-ordering instead of HIP-provided indexing\n");
    printf(" USE_PREP_KERNEL        - Use GPU kernel to initialize source data array pattern\n");
    printf(" USE_SINGLE_STREAM      - Use a single stream per GPU GFX executor instead of stream per Transfer\n");
    printf(" VALIDATE_DIRECT        - Validate GPU destination memory directly instead of staging GPU memory on host\n");
  }

  // Helper macro to switch between CSV and terminal output
#define PRINT_EV(NAME, VALUE, DESCRIPTION)                              \
  printf("%-20s%s%12d%s%s\n", NAME, outputToCsv ? "," : " = ", VALUE, outputToCsv ? "," : " : ",  (DESCRIPTION).c_str())

#define PRINT_ES(NAME, VALUE, DESCRIPTION)                           \
  printf("%-20s%s%12s%s%s\n", NAME, outputToCsv ? "," : " = ", VALUE, outputToCsv ? "," : " : ",  (DESCRIPTION).c_str())

  // Display env var settings
  void DisplayEnvVars() const
  {
    if (!outputToCsv)
    {
      printf("TransferBench v%s\n", TB_VERSION);
      printf("=====================================================\n");
      printf("[Common]\n");
    }
    else
      printf("EnvVar,Value,Description,(TransferBench v%s)\n", TB_VERSION);

    PRINT_EV("BLOCK_BYTES", blockBytes,
             std::string("Each CU gets a multiple of " + std::to_string(blockBytes) + " bytes to copy"));
    PRINT_EV("BYTE_OFFSET", byteOffset,
             std::string("Using byte offset of " + std::to_string(byteOffset)));
    PRINT_EV("CONTINUE_ON_ERROR", continueOnError,
             std::string(continueOnError ? "Continue on mismatch error" : "Stop after first error"));
    PRINT_EV("FILL_PATTERN", getenv("FILL_PATTERN") ? 1 : 0,
             (fillPattern.size() ? std::string(getenv("FILL_PATTERN")) : PrepSrcValueString()));
    PRINT_EV("GPU_KERNEL", gpuKernel,
             std::string("Using GPU kernel ") + std::to_string(gpuKernel) + " [" + std::string(GpuKernelNames[gpuKernel]) + "]");
    PRINT_EV("NUM_CPU_DEVICES", numCpuDevices,
             std::string("Using ") + std::to_string(numCpuDevices) + " CPU devices");
    PRINT_EV("NUM_GPU_DEVICES", numGpuDevices,
             std::string("Using ") + std::to_string(numGpuDevices) + " GPU devices");
    PRINT_EV("NUM_ITERATIONS", numIterations,
             std::string("Running ") + std::to_string(numIterations > 0 ? numIterations : -numIterations) + " "
             + (numIterations > 0 ? " timed iteration(s)" : "seconds(s) per Test"));
    PRINT_EV("NUM_WARMUPS", numWarmups,
             std::string("Running " + std::to_string(numWarmups) + " warmup iteration(s) per Test"));
    PRINT_EV("SHARED_MEM_BYTES", sharedMemBytes,
             std::string("Using " + std::to_string(sharedMemBytes) + " shared mem per threadblock"));
    PRINT_EV("USE_INTERACTIVE", useInteractive,
             std::string("Running in ") + (useInteractive ? "interactive" : "non-interactive") + " mode");
    PRINT_EV("USE_PCIE_INDEX", usePcieIndexing,
             std::string("Use ") + (usePcieIndexing ? "PCIe" : "HIP") + " GPU device indexing");
    PRINT_EV("USE_PREP_KERNEL", usePrepSrcKernel,
             std::string("Using ") + (usePrepSrcKernel ? "GPU kernels" : "hipMemcpy") + " to initialize source data");
    PRINT_EV("USE_SINGLE_STREAM", useSingleStream,
             std::string("Using single stream per ") + (useSingleStream ? "device" : "Transfer"));
    PRINT_EV("VALIDATE_DIRECT", validateDirect,
             std::string("Validate GPU destination memory ") + (validateDirect ? "directly" : "via CPU staging buffer"));
    printf("\n");
  };

  // Display env var for P2P Benchmark preset
  void DisplayP2PBenchmarkEnvVars() const
  {
    DisplayEnvVars();

    if (!outputToCsv)
      printf("[P2P Related]\n");

    PRINT_EV("NUM_CPU_SE", numCpuSubExecs,
             std::string("Using ") + std::to_string(numCpuSubExecs) + " CPU subexecutors");
    PRINT_EV("NUM_GPU_SE", numGpuSubExecs,
             std::string("Using ") + std::to_string(numGpuSubExecs) + " GPU subexecutors");
    PRINT_EV("USE_GPU_DMA", useDmaCopy,
             std::string("Using GPU-") + (useDmaCopy ? "DMA" : "GFX") + " as GPU executor");
    PRINT_EV("USE_REMOTE_READ", useRemoteRead,
             std::string("Using ") + (useRemoteRead ? "DST" : "SRC") + " as executor");
    printf("\n");
  }

  // Display env var settings
  void DisplaySweepEnvVars() const
  {
    DisplayEnvVars();

    if (!outputToCsv)
      printf("[Sweep Related]\n");
    PRINT_ES("SWEEP_DST", sweepDst.c_str(),
             std::string("Destination Memory Types to sweep"));
    PRINT_ES("SWEEP_EXE", sweepExe.c_str(),
             std::string("Executor Types to sweep"));
    PRINT_EV("SWEEP_MAX", sweepMax,
             std::string("Max simultaneous transfers (0 = no limit)"));
    PRINT_EV("SWEEP_MIN", sweepMin,
             std::string("Min simultaenous transfers"));
    PRINT_EV("SWEEP_RAND_BYTES", sweepRandBytes,
             std::string("Using ") + (sweepRandBytes ? "random" : "constant") + " number of bytes per Transfer");
    PRINT_EV("SWEEP_SEED", sweepSeed,
             std::string("Random seed set to ") + std::to_string(sweepSeed));
    PRINT_ES("SWEEP_SRC", sweepSrc.c_str(),
             std::string("Source Memory Types to sweep"));
    PRINT_EV("SWEEP_TEST_LIMIT", sweepTestLimit,
             std::string("Max number of tests to run during sweep (0 = no limit)"));
    PRINT_EV("SWEEP_TIME_LIMIT", sweepTimeLimit,
             std::string("Max number of seconds to run sweep for  (0 = no limit)"));
    PRINT_EV("SWEEP_XGMI_MAX", sweepXgmiMax,
             std::string("Max number of XGMI hops for Transfers (-1 = no limit)"));
    PRINT_EV("SWEEP_XGMI_MIN", sweepXgmiMin,
             std::string("Min number of XGMI hops for Transfers"));
    printf("\n");
  }

  // Helper function that gets parses environment variable or sets to default value
  static int GetEnvVar(std::string const& varname, int defaultValue)
  {
    if (getenv(varname.c_str()))
      return atoi(getenv(varname.c_str()));
    return defaultValue;
  }

  static std::string GetEnvVar(std::string const& varname, std::string const& defaultValue)
  {
    if (getenv(varname.c_str()))
      return getenv(varname.c_str());
    return defaultValue;
  }
};

#endif