/*

 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "memory/metaspace/metaspaceCommon.hpp"

#include "memory/metaspace/virtualSpaceNode.hpp"

#include "utilities/debug.hpp"

#include "utilities/globalDefinitions.hpp"

#include "utilities/ostream.hpp"

namespace metaspace {

DEBUG_ONLY(internal_statistics_t g_internal_statistics;)

// Print a size, in words, scaled.

void print_scaled_words(outputStream* st, size_t word_size, size_t scale, int width) {

  print_human_readable_size(st, word_size * sizeof(MetaWord), scale, width);

}

// Convenience helper: prints a size value and a percentage.

void print_scaled_words_and_percentage(outputStream* st, size_t word_size, size_t compare_word_size, size_t scale, int width) {

  print_scaled_words(st, word_size, scale, width);

  st->print(" (");

  print_percentage(st, compare_word_size, word_size);

  st->print(")");

}

// Print a human readable size.

// byte_size: size, in bytes, to be printed.

// scale: one of 1 (byte-wise printing), sizeof(word) (word-size printing), K, M, G (scaled by KB, MB, GB respectively,

//         or 0, which means the best scale is choosen dynamically.

// width: printing width.

void print_human_readable_size(outputStream* st, size_t byte_size, size_t scale, int width)  {

  if (scale == 0) {

    // Dynamic mode. Choose scale for this value.

    if (byte_size == 0) {

      // Zero values are printed as bytes.

      scale = 1;

    } else {

      if (byte_size >= G) {

        scale = G;

      } else if (byte_size >= M) {

        scale = M;

      } else if (byte_size >= K) {

        scale = K;

      } else {

        scale = 1;

      }

    }

    return print_human_readable_size(st, byte_size, scale, width);

  }

#ifdef ASSERT

  assert(scale == 1 || scale == BytesPerWord || scale == K || scale == M || scale == G, "Invalid scale");

  // Special case: printing wordsize should only be done with word-sized values

  if (scale == BytesPerWord) {

    assert(byte_size % BytesPerWord == 0, "not word sized");

  }

#endif

  if (scale == 1) {

    st->print("%*" PRIuPTR " bytes", width, byte_size);

  } else if (scale == BytesPerWord) {

    st->print("%*" PRIuPTR " words", width, byte_size / BytesPerWord);

  } else {

    const char* display_unit = "";

    switch(scale) {

      case 1: display_unit = "bytes"; break;

      case BytesPerWord: display_unit = "words"; break;

      case K: display_unit = "KB"; break;

      case M: display_unit = "MB"; break;

      case G: display_unit = "GB"; break;

      default:

        ShouldNotReachHere();

    }

    float display_value = (float) byte_size / scale;

    // Since we use width to display a number with two trailing digits, increase it a bit.

    width += 3;

    // Prevent very small but non-null values showing up as 0.00.

    if (byte_size > 0 && display_value < 0.01f) {

      st->print("%*s %s", width, "<0.01", display_unit);

    } else {

      st->print("%*.2f %s", width, display_value, display_unit);

    }

  }

}

// Prints a percentage value. Values smaller than 1% but not 0 are displayed as "<1%", values

// larger than 99% but not 100% are displayed as ">100%".

void print_percentage(outputStream* st, size_t total, size_t part) {

  if (total == 0) {

    st->print("  ?%%");

  } else if (part == 0) {

    st->print("  0%%");

  } else if (part == total) {

    st->print("100%%");

  } else {

    // Note: clearly print very-small-but-not-0% and very-large-but-not-100% percentages.

    float p = ((float)part / total) * 100.0f;

    if (p < 1.0f) {

      st->print(" <1%%");

    } else if (p > 99.0f){

      st->print(">99%%");

    } else {

      st->print("%3.0f%%", p);

    }

  }

}

// Returns size of this chunk type.

size_t get_size_for_nonhumongous_chunktype(ChunkIndex chunktype, bool is_class) {

  assert(is_valid_nonhumongous_chunktype(chunktype), "invalid chunk type.");

  size_t size = 0;

  if (is_class) {

    switch(chunktype) {

      case SpecializedIndex: size = ClassSpecializedChunk; break;

      case SmallIndex: size = ClassSmallChunk; break;

      case MediumIndex: size = ClassMediumChunk; break;

      default:

        ShouldNotReachHere();

    }

  } else {

    switch(chunktype) {

      case SpecializedIndex: size = SpecializedChunk; break;

      case SmallIndex: size = SmallChunk; break;

      case MediumIndex: size = MediumChunk; break;

      default:

        ShouldNotReachHere();

    }

  }

  return size;

}

ChunkIndex get_chunk_type_by_size(size_t size, bool is_class) {

  if (is_class) {

    if (size == ClassSpecializedChunk) {

      return SpecializedIndex;

    } else if (size == ClassSmallChunk) {

      return SmallIndex;

    } else if (size == ClassMediumChunk) {

      return MediumIndex;

    } else if (size > ClassMediumChunk) {

      // A valid humongous chunk size is a multiple of the smallest chunk size.

      assert(is_aligned(size, ClassSpecializedChunk), "Invalid chunk size");

      return HumongousIndex;

    }

  } else {

    if (size == SpecializedChunk) {

      return SpecializedIndex;

    } else if (size == SmallChunk) {

      return SmallIndex;

    } else if (size == MediumChunk) {

      return MediumIndex;

    } else if (size > MediumChunk) {

      // A valid humongous chunk size is a multiple of the smallest chunk size.

      assert(is_aligned(size, SpecializedChunk), "Invalid chunk size");

      return HumongousIndex;

    }

  }

  ShouldNotReachHere();

  return (ChunkIndex)-1;

}

ChunkIndex next_chunk_index(ChunkIndex i) {

  assert(i < NumberOfInUseLists, "Out of bound");

  return (ChunkIndex) (i+1);

}

ChunkIndex prev_chunk_index(ChunkIndex i) {

  assert(i > ZeroIndex, "Out of bound");

  return (ChunkIndex) (i-1);

}

} // namespace metaspace