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// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
// vim: ts=8 sw=2 smarttab
#include "ReadRequest.h"
#define dout_subsys ceph_subsys_rbd_pwl
#undef dout_prefix
#define dout_prefix *_dout << "librbd::cache::pwl::ssd::ReadRequest: " << this << " " \
<< __func__ << ": "
namespace librbd {
namespace cache {
namespace pwl {
namespace ssd {
void C_ReadRequest::finish(int r) {
ldout(m_cct, 20) << "(" << get_name() << "): r=" << r << dendl;
int hits = 0;
int misses = 0;
int hit_bytes = 0;
int miss_bytes = 0;
if (r >= 0) {
/*
* At this point the miss read has completed. We'll iterate through
* m_read_extents and produce *m_out_bl by assembling pieces of m_miss_bl
* and the individual hit extent bufs in the read extents that represent
* hits.
*/
uint64_t miss_bl_offset = 0;
for (auto extent : read_extents) {
if (extent->m_bl.length()) {
/* This was a hit */
bufferlist data_bl;
if (extent->writesame) {
int data_len = extent->m_bl.length();
int read_buffer_offset = extent->truncate_offset;
if (extent->need_to_truncate && extent->truncate_offset >= data_len) {
read_buffer_offset = (extent->truncate_offset) % data_len;
}
// build data and truncate
bufferlist temp_bl;
uint64_t total_left_bytes = read_buffer_offset + extent->second;
while (total_left_bytes > 0) {
temp_bl.append(extent->m_bl);
total_left_bytes = total_left_bytes - data_len;
}
data_bl.substr_of(temp_bl, read_buffer_offset, extent->second);
m_out_bl->claim_append(data_bl);
} else if (extent->need_to_truncate) {
assert(extent->m_bl.length() >= extent->truncate_offset + extent->second);
data_bl.substr_of(extent->m_bl, extent->truncate_offset, extent->second);
m_out_bl->claim_append(data_bl);
} else {
assert(extent->second == extent->m_bl.length());
m_out_bl->claim_append(extent->m_bl);
}
++hits;
hit_bytes += extent->second;
} else {
/* This was a miss. */
++misses;
miss_bytes += extent->second;
bufferlist miss_extent_bl;
miss_extent_bl.substr_of(miss_bl, miss_bl_offset, extent->second);
/* Add this read miss bufferlist to the output bufferlist */
m_out_bl->claim_append(miss_extent_bl);
/* Consume these bytes in the read miss bufferlist */
miss_bl_offset += extent->second;
}
}
}
ldout(m_cct, 20) << "(" << get_name() << "): r=" << r << " bl=" << *m_out_bl << dendl;
utime_t now = ceph_clock_now();
ceph_assert((int)m_out_bl->length() == hit_bytes + miss_bytes);
m_on_finish->complete(r);
m_perfcounter->inc(l_librbd_pwl_rd_bytes, hit_bytes + miss_bytes);
m_perfcounter->inc(l_librbd_pwl_rd_hit_bytes, hit_bytes);
m_perfcounter->tinc(l_librbd_pwl_rd_latency, now - m_arrived_time);
if (!misses) {
m_perfcounter->inc(l_librbd_pwl_rd_hit_req, 1);
m_perfcounter->tinc(l_librbd_pwl_rd_hit_latency, now - m_arrived_time);
} else {
if (hits) {
m_perfcounter->inc(l_librbd_pwl_rd_part_hit_req, 1);
}
}
}
} // namespace ssd
} // namespace pwl
} // namespace cache
} // namespace librbd
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