ceph/src/librbd/cache/pwl/rwl/ReadRequest.cc

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3
   4 #include "ReadRequest.h"
   5
   6 #define dout_subsys ceph_subsys_rbd_pwl
   7 #undef dout_prefix
   8 #define dout_prefix *_dout << "librbd::cache::pwl::rwl::ReadRequest: " << this << " " \
   9                            <<  __func__ << ": "
  10
  11 namespace librbd {
  12 namespace cache {
  13 namespace pwl {
  14 namespace rwl {
  15
  16 void C_ReadRequest::finish(int r) {
  17   ldout(m_cct, 20) << "(" << get_name() << "): r=" << r << dendl;
  18   int hits = 0;
  19   int misses = 0;
  20   int hit_bytes = 0;
  21   int miss_bytes = 0;
  22   if (r >= 0) {
  23     /*
  24      * At this point the miss read has completed. We'll iterate through
  25      * read_extents and produce *m_out_bl by assembling pieces of miss_bl
  26      * and the individual hit extent bufs in the read extents that represent
  27      * hits.
  28      */
  29     uint64_t miss_bl_offset = 0;
  30     for (auto extent : read_extents) {
  31       if (extent->m_bl.length()) {
  32         /* This was a hit */
  33         ceph_assert(extent->second == extent->m_bl.length());
  34         ++hits;
  35         hit_bytes += extent->second;
  36         m_out_bl->claim_append(extent->m_bl);
  37       } else {
  38         /* This was a miss. */
  39         ++misses;
  40         miss_bytes += extent->second;
  41         bufferlist miss_extent_bl;
  42         miss_extent_bl.substr_of(miss_bl, miss_bl_offset, extent->second);
  43         /* Add this read miss bufferlist to the output bufferlist */
  44         m_out_bl->claim_append(miss_extent_bl);
  45         /* Consume these bytes in the read miss bufferlist */
  46         miss_bl_offset += extent->second;
  47       }
  48     }
  49   }
  50   ldout(m_cct, 20) << "(" << get_name() << "): r=" << r << " bl=" << *m_out_bl << dendl;
  51   utime_t now = ceph_clock_now();
  52   ceph_assert((int)m_out_bl->length() == hit_bytes + miss_bytes);
  53   m_on_finish->complete(r);
  54   m_perfcounter->inc(l_librbd_pwl_rd_bytes, hit_bytes + miss_bytes);
  55   m_perfcounter->inc(l_librbd_pwl_rd_hit_bytes, hit_bytes);
  56   m_perfcounter->tinc(l_librbd_pwl_rd_latency, now - m_arrived_time);
  57   if (!misses) {
  58     m_perfcounter->inc(l_librbd_pwl_rd_hit_req, 1);
  59     m_perfcounter->tinc(l_librbd_pwl_rd_hit_latency, now - m_arrived_time);
  60   } else {
  61     if (hits) {
  62       m_perfcounter->inc(l_librbd_pwl_rd_part_hit_req, 1);
  63     }
  64   }
  65 }
  66
  67 } // namespace rwl
  68 } // namespace pwl
  69 } // namespace cache
  70 } // namespace librbd