ceph/src/os/bluestore/zoned_types.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3 #ifndef CEPH_OS_BLUESTORE_ZONED_TYPES_H
   4 #define CEPH_OS_BLUESTORE_ZONED_TYPES_H
   5
   6 #include "include/types.h"
   7 #include "kv/KeyValueDB.h"
   8 #include "os/kv.h"
   9
  10 // Tracks two bits of information about the state of a zone: (1) number of dead
  11 // bytes in a zone and (2) the write pointer.  We use the existing
  12 // Int64ArrayMergeOperator for merge and avoid the cost of point queries.
  13 //
  14 // We use the same struct for an on-disk and in-memory representation of the
  15 // state.
  16 struct zone_state_t {
  17   uint64_t num_dead_bytes = 0;  ///< dead bytes deallocated (behind the write pointer)
  18   uint64_t write_pointer = 0;   ///< relative offset within the zone
  19
  20   void encode(ceph::buffer::list &bl) const {
  21     using ceph::encode;
  22     encode(write_pointer, bl);
  23     encode(num_dead_bytes, bl);
  24   }
  25   void decode(ceph::buffer::list::const_iterator &p) {
  26     using ceph::decode;
  27     decode(write_pointer, p);
  28     decode(num_dead_bytes, p);
  29   }
  30
  31   void reset() {
  32     write_pointer = 0;
  33     num_dead_bytes = 0;
  34   }
  35
  36   uint64_t get_num_dead_bytes() const {
  37     return num_dead_bytes;
  38   }
  39
  40   uint64_t get_num_live_bytes() const {
  41     return write_pointer - num_dead_bytes;
  42   }
  43
  44   uint64_t get_write_pointer() const {
  45     return write_pointer;
  46   }
  47
  48   void increment_num_dead_bytes(uint64_t num_bytes) {
  49     num_dead_bytes += num_bytes;
  50   }
  51
  52   void increment_write_pointer(uint64_t num_bytes) {
  53     write_pointer += num_bytes;
  54   }
  55
  56   friend std::ostream& operator<<(
  57     std::ostream& out,
  58     const zone_state_t& zone_state) {
  59     return out << std::hex
  60                << " dead bytes: 0x" << zone_state.get_num_dead_bytes()
  61                << " write pointer: 0x"  << zone_state.get_write_pointer()
  62                << " " << std::dec;
  63   }
  64 };
  65
  66 #endif