+++ /dev/null
-// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
-// vim: ts=8 sw=2 smarttab
-/*
- * Ceph - scalable distributed file system
- *
- * Copyright (C) 2004-2006 Sage Weil <sage@newdream.net>
- *
- * This is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License version 2.1, as published by the Free Software
- * Foundation. See file COPYING.
- *
- */
-
-#include "common/perf_counters.h"
-#include "common/dout.h"
-#include "include/Context.h"
-#include "msg/Messenger.h"
-#include "osdc/Journaler.h"
-#include "common/errno.h"
-#include "include/assert.h"
-#include "common/Finisher.h"
-
-#define dout_subsys ceph_subsys_journaler
-#undef dout_prefix
-#define dout_prefix *_dout << objecter->messenger->get_myname() \
- << ".journaler." << name << (readonly ? "(ro) ":"(rw) ")
-
-using std::chrono::seconds;
-
-
-class Journaler::C_DelayFlush : public Context {
- Journaler *journaler;
- public:
- C_DelayFlush(Journaler *j) : journaler(j) {}
- void finish(int r) override {
- journaler->_do_delayed_flush();
- }
-};
-
-void Journaler::set_readonly()
-{
- lock_guard l(lock);
-
- ldout(cct, 1) << "set_readonly" << dendl;
- readonly = true;
-}
-
-void Journaler::set_writeable()
-{
- lock_guard l(lock);
-
- ldout(cct, 1) << "set_writeable" << dendl;
- readonly = false;
-}
-
-void Journaler::create(file_layout_t *l, stream_format_t const sf)
-{
- lock_guard lk(lock);
-
- assert(!readonly);
- state = STATE_ACTIVE;
-
- stream_format = sf;
- journal_stream.set_format(sf);
- _set_layout(l);
-
- prezeroing_pos = prezero_pos = write_pos = flush_pos =
- safe_pos = read_pos = requested_pos = received_pos =
- expire_pos = trimming_pos = trimmed_pos =
- next_safe_pos = layout.get_period();
-
- ldout(cct, 1) << "created blank journal at inode 0x" << std::hex << ino
- << std::dec << ", format=" << stream_format << dendl;
-}
-
-void Journaler::set_layout(file_layout_t const *l)
-{
- lock_guard lk(lock);
- _set_layout(l);
-}
-
-void Journaler::_set_layout(file_layout_t const *l)
-{
- layout = *l;
-
- assert(layout.pool_id == pg_pool);
- last_written.layout = layout;
- last_committed.layout = layout;
-
- // prefetch intelligently.
- // (watch out, this is big if you use big objects or weird striping)
- uint64_t periods = cct->_conf->journaler_prefetch_periods;
- if (periods < 2)
- periods = 2; // we need at least 2 periods to make progress.
- fetch_len = layout.get_period() * periods;
-}
-
-
-/***************** HEADER *******************/
-
-ostream& operator<<(ostream &out, const Journaler::Header &h)
-{
- return out << "loghead(trim " << h.trimmed_pos
- << ", expire " << h.expire_pos
- << ", write " << h.write_pos
- << ", stream_format " << (int)(h.stream_format)
- << ")";
-}
-
-class Journaler::C_ReadHead : public Context {
- Journaler *ls;
-public:
- bufferlist bl;
- explicit C_ReadHead(Journaler *l) : ls(l) {}
- void finish(int r) override {
- ls->_finish_read_head(r, bl);
- }
-};
-
-class Journaler::C_RereadHead : public Context {
- Journaler *ls;
- Context *onfinish;
-public:
- bufferlist bl;
- C_RereadHead(Journaler *l, Context *onfinish_) : ls (l),
- onfinish(onfinish_) {}
- void finish(int r) override {
- ls->_finish_reread_head(r, bl, onfinish);
- }
-};
-
-class Journaler::C_ProbeEnd : public Context {
- Journaler *ls;
-public:
- uint64_t end;
- explicit C_ProbeEnd(Journaler *l) : ls(l), end(-1) {}
- void finish(int r) override {
- ls->_finish_probe_end(r, end);
- }
-};
-
-class Journaler::C_ReProbe : public Context {
- Journaler *ls;
- C_OnFinisher *onfinish;
-public:
- uint64_t end;
- C_ReProbe(Journaler *l, C_OnFinisher *onfinish_) :
- ls(l), onfinish(onfinish_), end(0) {}
- void finish(int r) override {
- ls->_finish_reprobe(r, end, onfinish);
- }
-};
-
-void Journaler::recover(Context *onread)
-{
- lock_guard l(lock);
- if (stopping) {
- onread->complete(-EAGAIN);
- return;
- }
-
- ldout(cct, 1) << "recover start" << dendl;
- assert(state != STATE_ACTIVE);
- assert(readonly);
-
- if (onread)
- waitfor_recover.push_back(wrap_finisher(onread));
-
- if (state != STATE_UNDEF) {
- ldout(cct, 1) << "recover - already recovering" << dendl;
- return;
- }
-
- ldout(cct, 1) << "read_head" << dendl;
- state = STATE_READHEAD;
- C_ReadHead *fin = new C_ReadHead(this);
- _read_head(fin, &fin->bl);
-}
-
-void Journaler::_read_head(Context *on_finish, bufferlist *bl)
-{
- // lock is locked
- assert(state == STATE_READHEAD || state == STATE_REREADHEAD);
-
- object_t oid = file_object_t(ino, 0);
- object_locator_t oloc(pg_pool);
- objecter->read_full(oid, oloc, CEPH_NOSNAP, bl, 0, wrap_finisher(on_finish));
-}
-
-void Journaler::reread_head(Context *onfinish)
-{
- lock_guard l(lock);
- _reread_head(wrap_finisher(onfinish));
-}
-
-/**
- * Re-read the head from disk, and set the write_pos, expire_pos, trimmed_pos
- * from the on-disk header. This switches the state to STATE_REREADHEAD for
- * the duration, and you shouldn't start a re-read while other operations are
- * in-flight, nor start other operations while a re-read is in progress.
- * Also, don't call this until the Journaler has finished its recovery and has
- * gone STATE_ACTIVE!
- */
-void Journaler::_reread_head(Context *onfinish)
-{
- ldout(cct, 10) << "reread_head" << dendl;
- assert(state == STATE_ACTIVE);
-
- state = STATE_REREADHEAD;
- C_RereadHead *fin = new C_RereadHead(this, onfinish);
- _read_head(fin, &fin->bl);
-}
-
-void Journaler::_finish_reread_head(int r, bufferlist& bl, Context *finish)
-{
- lock_guard l(lock);
-
- //read on-disk header into
- assert(bl.length() || r < 0 );
-
- // unpack header
- if (r == 0) {
- Header h;
- bufferlist::iterator p = bl.begin();
- try {
- ::decode(h, p);
- } catch (const buffer::error &e) {
- finish->complete(-EINVAL);
- return;
- }
- prezeroing_pos = prezero_pos = write_pos = flush_pos = safe_pos = next_safe_pos
- = h.write_pos;
- expire_pos = h.expire_pos;
- trimmed_pos = trimming_pos = h.trimmed_pos;
- init_headers(h);
- state = STATE_ACTIVE;
- }
-
- finish->complete(r);
-}
-
-void Journaler::_finish_read_head(int r, bufferlist& bl)
-{
- lock_guard l(lock);
-
- assert(state == STATE_READHEAD);
-
- if (r!=0) {
- ldout(cct, 0) << "error getting journal off disk" << dendl;
- list<Context*> ls;
- ls.swap(waitfor_recover);
- finish_contexts(cct, ls, r);
- return;
- }
-
- if (bl.length() == 0) {
- ldout(cct, 1) << "_finish_read_head r=" << r
- << " read 0 bytes, assuming empty log" << dendl;
- state = STATE_ACTIVE;
- list<Context*> ls;
- ls.swap(waitfor_recover);
- finish_contexts(cct, ls, 0);
- return;
- }
-
- // unpack header
- bool corrupt = false;
- Header h;
- bufferlist::iterator p = bl.begin();
- try {
- ::decode(h, p);
-
- if (h.magic != magic) {
- ldout(cct, 0) << "on disk magic '" << h.magic << "' != my magic '"
- << magic << "'" << dendl;
- corrupt = true;
- } else if (h.write_pos < h.expire_pos || h.expire_pos < h.trimmed_pos) {
- ldout(cct, 0) << "Corrupt header (bad offsets): " << h << dendl;
- corrupt = true;
- }
- } catch (const buffer::error &e) {
- corrupt = true;
- }
-
- if (corrupt) {
- list<Context*> ls;
- ls.swap(waitfor_recover);
- finish_contexts(cct, ls, -EINVAL);
- return;
- }
-
- prezeroing_pos = prezero_pos = write_pos = flush_pos = safe_pos = next_safe_pos
- = h.write_pos;
- read_pos = requested_pos = received_pos = expire_pos = h.expire_pos;
- trimmed_pos = trimming_pos = h.trimmed_pos;
-
- init_headers(h);
- _set_layout(&h.layout);
- stream_format = h.stream_format;
- journal_stream.set_format(h.stream_format);
-
- ldout(cct, 1) << "_finish_read_head " << h
- << ". probing for end of log (from " << write_pos << ")..."
- << dendl;
- C_ProbeEnd *fin = new C_ProbeEnd(this);
- state = STATE_PROBING;
- _probe(fin, &fin->end);
-}
-
-void Journaler::_probe(Context *finish, uint64_t *end)
-{
- // lock is locked
- ldout(cct, 1) << "probing for end of the log" << dendl;
- assert(state == STATE_PROBING || state == STATE_REPROBING);
- // probe the log
- filer.probe(ino, &layout, CEPH_NOSNAP,
- write_pos, end, true, 0, wrap_finisher(finish));
-}
-
-void Journaler::_reprobe(C_OnFinisher *finish)
-{
- ldout(cct, 10) << "reprobe" << dendl;
- assert(state == STATE_ACTIVE);
-
- state = STATE_REPROBING;
- C_ReProbe *fin = new C_ReProbe(this, finish);
- _probe(fin, &fin->end);
-}
-
-
-void Journaler::_finish_reprobe(int r, uint64_t new_end,
- C_OnFinisher *onfinish)
-{
- lock_guard l(lock);
-
- assert(new_end >= write_pos || r < 0);
- ldout(cct, 1) << "_finish_reprobe new_end = " << new_end
- << " (header had " << write_pos << ")."
- << dendl;
- prezeroing_pos = prezero_pos = write_pos = flush_pos = safe_pos = next_safe_pos = new_end;
- state = STATE_ACTIVE;
- onfinish->complete(r);
-}
-
-void Journaler::_finish_probe_end(int r, uint64_t end)
-{
- lock_guard l(lock);
-
- assert(state == STATE_PROBING);
- if (r < 0) { // error in probing
- goto out;
- }
- if (((int64_t)end) == -1) {
- end = write_pos;
- ldout(cct, 1) << "_finish_probe_end write_pos = " << end << " (header had "
- << write_pos << "). log was empty. recovered." << dendl;
- ceph_abort(); // hrm.
- } else {
- assert(end >= write_pos);
- ldout(cct, 1) << "_finish_probe_end write_pos = " << end
- << " (header had " << write_pos << "). recovered."
- << dendl;
- }
-
- state = STATE_ACTIVE;
-
- prezeroing_pos = prezero_pos = write_pos = flush_pos = safe_pos = next_safe_pos = end;
-
-out:
- // done.
- list<Context*> ls;
- ls.swap(waitfor_recover);
- finish_contexts(cct, ls, r);
-}
-
-class Journaler::C_RereadHeadProbe : public Context
-{
- Journaler *ls;
- C_OnFinisher *final_finish;
-public:
- C_RereadHeadProbe(Journaler *l, C_OnFinisher *finish) :
- ls(l), final_finish(finish) {}
- void finish(int r) override {
- ls->_finish_reread_head_and_probe(r, final_finish);
- }
-};
-
-void Journaler::reread_head_and_probe(Context *onfinish)
-{
- lock_guard l(lock);
-
- assert(state == STATE_ACTIVE);
- _reread_head(new C_RereadHeadProbe(this, wrap_finisher(onfinish)));
-}
-
-void Journaler::_finish_reread_head_and_probe(int r, C_OnFinisher *onfinish)
-{
- // Expect to be called back from finish_reread_head, which already takes lock
- // lock is locked
-
- assert(!r); //if we get an error, we're boned
- _reprobe(onfinish);
-}
-
-
-// WRITING
-
-class Journaler::C_WriteHead : public Context {
-public:
- Journaler *ls;
- Header h;
- C_OnFinisher *oncommit;
- C_WriteHead(Journaler *l, Header& h_, C_OnFinisher *c) : ls(l), h(h_),
- oncommit(c) {}
- void finish(int r) override {
- ls->_finish_write_head(r, h, oncommit);
- }
-};
-
-void Journaler::write_head(Context *oncommit)
-{
- lock_guard l(lock);
- _write_head(oncommit);
-}
-
-
-void Journaler::_write_head(Context *oncommit)
-{
- assert(!readonly);
- assert(state == STATE_ACTIVE);
- last_written.trimmed_pos = trimmed_pos;
- last_written.expire_pos = expire_pos;
- last_written.unused_field = expire_pos;
- last_written.write_pos = safe_pos;
- last_written.stream_format = stream_format;
- ldout(cct, 10) << "write_head " << last_written << dendl;
-
- // Avoid persisting bad pointers in case of bugs
- assert(last_written.write_pos >= last_written.expire_pos);
- assert(last_written.expire_pos >= last_written.trimmed_pos);
-
- last_wrote_head = ceph::real_clock::now();
-
- bufferlist bl;
- ::encode(last_written, bl);
- SnapContext snapc;
-
- object_t oid = file_object_t(ino, 0);
- object_locator_t oloc(pg_pool);
- objecter->write_full(oid, oloc, snapc, bl, ceph::real_clock::now(), 0,
- wrap_finisher(new C_WriteHead(
- this, last_written,
- wrap_finisher(oncommit))),
- 0, 0, write_iohint);
-}
-
-void Journaler::_finish_write_head(int r, Header &wrote,
- C_OnFinisher *oncommit)
-{
- lock_guard l(lock);
-
- if (r < 0) {
- lderr(cct) << "_finish_write_head got " << cpp_strerror(r) << dendl;
- handle_write_error(r);
- return;
- }
- assert(!readonly);
- ldout(cct, 10) << "_finish_write_head " << wrote << dendl;
- last_committed = wrote;
- if (oncommit) {
- oncommit->complete(r);
- }
-
- _trim(); // trim?
-}
-
-
-/***************** WRITING *******************/
-
-class Journaler::C_Flush : public Context {
- Journaler *ls;
- uint64_t start;
- ceph::real_time stamp;
-public:
- C_Flush(Journaler *l, int64_t s, ceph::real_time st)
- : ls(l), start(s), stamp(st) {}
- void finish(int r) override {
- ls->_finish_flush(r, start, stamp);
- }
-};
-
-void Journaler::_finish_flush(int r, uint64_t start, ceph::real_time stamp)
-{
- lock_guard l(lock);
- assert(!readonly);
-
- if (r < 0) {
- lderr(cct) << "_finish_flush got " << cpp_strerror(r) << dendl;
- handle_write_error(r);
- return;
- }
-
- assert(start < flush_pos);
-
- // calc latency?
- if (logger) {
- ceph::timespan lat = ceph::real_clock::now() - stamp;
- logger->tinc(logger_key_lat, lat);
- }
-
- // adjust safe_pos
- auto it = pending_safe.find(start);
- assert(it != pending_safe.end());
- pending_safe.erase(it);
- if (pending_safe.empty())
- safe_pos = next_safe_pos;
- else
- safe_pos = pending_safe.begin()->second;
-
- ldout(cct, 10) << "_finish_flush safe from " << start
- << ", pending_safe " << pending_safe
- << ", (prezeroing/prezero)/write/flush/safe positions now "
- << "(" << prezeroing_pos << "/" << prezero_pos << ")/"
- << write_pos << "/" << flush_pos << "/" << safe_pos
- << dendl;
-
- // kick waiters <= safe_pos
- if (!waitfor_safe.empty()) {
- list<Context*> ls;
- while (!waitfor_safe.empty()) {
- auto it = waitfor_safe.begin();
- if (it->first > safe_pos)
- break;
- ls.splice(ls.end(), it->second);
- waitfor_safe.erase(it);
- }
- finish_contexts(cct, ls);
- }
-}
-
-
-
-uint64_t Journaler::append_entry(bufferlist& bl)
-{
- unique_lock l(lock);
-
- assert(!readonly);
- uint32_t s = bl.length();
-
- // append
- size_t delta = bl.length() + journal_stream.get_envelope_size();
- // write_buf space is nearly full
- if (!write_buf_throttle.get_or_fail(delta)) {
- l.unlock();
- ldout(cct, 10) << "write_buf_throttle wait, delta " << delta << dendl;
- write_buf_throttle.get(delta);
- l.lock();
- }
- ldout(cct, 20) << "write_buf_throttle get, delta " << delta << dendl;
- size_t wrote = journal_stream.write(bl, &write_buf, write_pos);
- ldout(cct, 10) << "append_entry len " << s << " to " << write_pos << "~"
- << wrote << dendl;
- write_pos += wrote;
-
- // flush previous object?
- uint64_t su = get_layout_period();
- assert(su > 0);
- uint64_t write_off = write_pos % su;
- uint64_t write_obj = write_pos / su;
- uint64_t flush_obj = flush_pos / su;
- if (write_obj != flush_obj) {
- ldout(cct, 10) << " flushing completed object(s) (su " << su << " wro "
- << write_obj << " flo " << flush_obj << ")" << dendl;
- _do_flush(write_buf.length() - write_off);
-
- // if _do_flush() skips flushing some data, it does do a best effort to
- // update next_safe_pos.
- if (write_buf.length() > 0 &&
- write_buf.length() <= wrote) { // the unflushed data are within this entry
- // set next_safe_pos to end of previous entry
- next_safe_pos = write_pos - wrote;
- }
- }
-
- return write_pos;
-}
-
-
-void Journaler::_do_flush(unsigned amount)
-{
- if (write_pos == flush_pos)
- return;
- assert(write_pos > flush_pos);
- assert(!readonly);
-
- // flush
- uint64_t len = write_pos - flush_pos;
- assert(len == write_buf.length());
- if (amount && amount < len)
- len = amount;
-
- // zero at least two full periods ahead. this ensures
- // that the next object will not exist.
- uint64_t period = get_layout_period();
- if (flush_pos + len + 2*period > prezero_pos) {
- _issue_prezero();
-
- int64_t newlen = prezero_pos - flush_pos - period;
- if (newlen <= 0) {
- ldout(cct, 10) << "_do_flush wanted to do " << flush_pos << "~" << len
- << " already too close to prezero_pos " << prezero_pos
- << ", zeroing first" << dendl;
- waiting_for_zero = true;
- return;
- }
- if (static_cast<uint64_t>(newlen) < len) {
- ldout(cct, 10) << "_do_flush wanted to do " << flush_pos << "~" << len
- << " but hit prezero_pos " << prezero_pos
- << ", will do " << flush_pos << "~" << newlen << dendl;
- len = newlen;
- } else {
- waiting_for_zero = false;
- }
- } else {
- waiting_for_zero = false;
- }
- ldout(cct, 10) << "_do_flush flushing " << flush_pos << "~" << len << dendl;
-
- // submit write for anything pending
- // flush _start_ pos to _finish_flush
- ceph::real_time now = ceph::real_clock::now();
- SnapContext snapc;
-
- Context *onsafe = new C_Flush(this, flush_pos, now); // on COMMIT
- pending_safe[flush_pos] = next_safe_pos;
-
- bufferlist write_bl;
-
- // adjust pointers
- if (len == write_buf.length()) {
- write_bl.swap(write_buf);
- next_safe_pos = write_pos;
- } else {
- write_buf.splice(0, len, &write_bl);
- // Keys of waitfor_safe map are journal entry boundaries.
- // Try finding a journal entry that we are actually flushing
- // and set next_safe_pos to end of it. This is best effort.
- // The one we found may not be the lastest flushing entry.
- auto p = waitfor_safe.lower_bound(flush_pos + len);
- if (p != waitfor_safe.end()) {
- if (p->first > flush_pos + len && p != waitfor_safe.begin())
- --p;
- if (p->first <= flush_pos + len && p->first > next_safe_pos)
- next_safe_pos = p->first;
- }
- }
-
- filer.write(ino, &layout, snapc,
- flush_pos, len, write_bl, ceph::real_clock::now(),
- 0,
- wrap_finisher(onsafe), write_iohint);
-
- flush_pos += len;
- assert(write_buf.length() == write_pos - flush_pos);
- write_buf_throttle.put(len);
- ldout(cct, 20) << "write_buf_throttle put, len " << len << dendl;
-
- ldout(cct, 10)
- << "_do_flush (prezeroing/prezero)/write/flush/safe pointers now at "
- << "(" << prezeroing_pos << "/" << prezero_pos << ")/" << write_pos
- << "/" << flush_pos << "/" << safe_pos << dendl;
-
- _issue_prezero();
-}
-
-
-void Journaler::wait_for_flush(Context *onsafe)
-{
- lock_guard l(lock);
- if (stopping) {
- onsafe->complete(-EAGAIN);
- return;
- }
- _wait_for_flush(onsafe);
-}
-
-void Journaler::_wait_for_flush(Context *onsafe)
-{
- assert(!readonly);
-
- // all flushed and safe?
- if (write_pos == safe_pos) {
- assert(write_buf.length() == 0);
- ldout(cct, 10)
- << "flush nothing to flush, (prezeroing/prezero)/write/flush/safe "
- "pointers at " << "(" << prezeroing_pos << "/" << prezero_pos << ")/"
- << write_pos << "/" << flush_pos << "/" << safe_pos << dendl;
- if (onsafe) {
- finisher->queue(onsafe, 0);
- }
- return;
- }
-
- // queue waiter
- if (onsafe) {
- waitfor_safe[write_pos].push_back(wrap_finisher(onsafe));
- }
-}
-
-void Journaler::flush(Context *onsafe)
-{
- lock_guard l(lock);
- _flush(wrap_finisher(onsafe));
-}
-
-void Journaler::_flush(C_OnFinisher *onsafe)
-{
- assert(!readonly);
-
- if (write_pos == flush_pos) {
- assert(write_buf.length() == 0);
- ldout(cct, 10) << "flush nothing to flush, (prezeroing/prezero)/write/"
- "flush/safe pointers at " << "(" << prezeroing_pos << "/" << prezero_pos
- << ")/" << write_pos << "/" << flush_pos << "/" << safe_pos
- << dendl;
- if (onsafe) {
- onsafe->complete(0);
- }
- } else {
- _do_flush();
- _wait_for_flush(onsafe);
- }
-
- // write head?
- if (_write_head_needed()) {
- _write_head();
- }
-}
-
-bool Journaler::_write_head_needed()
-{
- return last_wrote_head + seconds(cct->_conf->journaler_write_head_interval)
- < ceph::real_clock::now();
-}
-
-
-/*************** prezeroing ******************/
-
-struct C_Journaler_Prezero : public Context {
- Journaler *journaler;
- uint64_t from, len;
- C_Journaler_Prezero(Journaler *j, uint64_t f, uint64_t l)
- : journaler(j), from(f), len(l) {}
- void finish(int r) override {
- journaler->_finish_prezero(r, from, len);
- }
-};
-
-void Journaler::_issue_prezero()
-{
- assert(prezeroing_pos >= flush_pos);
-
- // we need to zero at least two periods, minimum, to ensure that we
- // have a full empty object/period in front of us.
- uint64_t num_periods = MAX(2, cct->_conf->journaler_prezero_periods);
-
- /*
- * issue zero requests based on write_pos, even though the invariant
- * is that we zero ahead of flush_pos.
- */
- uint64_t period = get_layout_period();
- uint64_t to = write_pos + period * num_periods + period - 1;
- to -= to % period;
-
- if (prezeroing_pos >= to) {
- ldout(cct, 20) << "_issue_prezero target " << to << " <= prezeroing_pos "
- << prezeroing_pos << dendl;
- return;
- }
-
- while (prezeroing_pos < to) {
- uint64_t len;
- if (prezeroing_pos % period == 0) {
- len = period;
- ldout(cct, 10) << "_issue_prezero removing " << prezeroing_pos << "~"
- << period << " (full period)" << dendl;
- } else {
- len = period - (prezeroing_pos % period);
- ldout(cct, 10) << "_issue_prezero zeroing " << prezeroing_pos << "~"
- << len << " (partial period)" << dendl;
- }
- SnapContext snapc;
- Context *c = wrap_finisher(new C_Journaler_Prezero(this, prezeroing_pos,
- len));
- filer.zero(ino, &layout, snapc, prezeroing_pos, len,
- ceph::real_clock::now(), 0, c);
- prezeroing_pos += len;
- }
-}
-
-// Lock cycle because we get called out of objecter callback (holding
-// objecter read lock), but there are also cases where we take the journaler
-// lock before calling into objecter to do I/O.
-void Journaler::_finish_prezero(int r, uint64_t start, uint64_t len)
-{
- lock_guard l(lock);
-
- ldout(cct, 10) << "_prezeroed to " << start << "~" << len
- << ", prezeroing/prezero was " << prezeroing_pos << "/"
- << prezero_pos << ", pending " << pending_zero
- << dendl;
- if (r < 0 && r != -ENOENT) {
- lderr(cct) << "_prezeroed got " << cpp_strerror(r) << dendl;
- handle_write_error(r);
- return;
- }
-
- assert(r == 0 || r == -ENOENT);
-
- if (start == prezero_pos) {
- prezero_pos += len;
- while (!pending_zero.empty() &&
- pending_zero.begin().get_start() == prezero_pos) {
- interval_set<uint64_t>::iterator b(pending_zero.begin());
- prezero_pos += b.get_len();
- pending_zero.erase(b);
- }
-
- if (waiting_for_zero) {
- _do_flush();
- }
- } else {
- pending_zero.insert(start, len);
- }
- ldout(cct, 10) << "_prezeroed prezeroing/prezero now " << prezeroing_pos
- << "/" << prezero_pos
- << ", pending " << pending_zero
- << dendl;
-}
-
-
-
-/***************** READING *******************/
-
-
-class Journaler::C_Read : public Context {
- Journaler *ls;
- uint64_t offset;
- uint64_t length;
-public:
- bufferlist bl;
- C_Read(Journaler *j, uint64_t o, uint64_t l) : ls(j), offset(o), length(l) {}
- void finish(int r) override {
- ls->_finish_read(r, offset, length, bl);
- }
-};
-
-class Journaler::C_RetryRead : public Context {
- Journaler *ls;
-public:
- explicit C_RetryRead(Journaler *l) : ls(l) {}
-
- void finish(int r) override {
- // Should only be called from waitfor_safe i.e. already inside lock
- // (ls->lock is locked
- ls->_prefetch();
- }
-};
-
-void Journaler::_finish_read(int r, uint64_t offset, uint64_t length,
- bufferlist& bl)
-{
- lock_guard l(lock);
-
- if (r < 0) {
- ldout(cct, 0) << "_finish_read got error " << r << dendl;
- error = r;
- } else {
- ldout(cct, 10) << "_finish_read got " << offset << "~" << bl.length()
- << dendl;
- if (bl.length() < length) {
- ldout(cct, 0) << "_finish_read got less than expected (" << length << ")"
- << dendl;
- error = -EINVAL;
- }
- }
-
- if (error) {
- if (on_readable) {
- C_OnFinisher *f = on_readable;
- on_readable = 0;
- f->complete(error);
- }
- return;
- }
-
- prefetch_buf[offset].swap(bl);
-
- try {
- _assimilate_prefetch();
- } catch (const buffer::error &err) {
- lderr(cct) << "_decode error from assimilate_prefetch" << dendl;
- error = -EINVAL;
- if (on_readable) {
- C_OnFinisher *f = on_readable;
- on_readable = 0;
- f->complete(error);
- }
- return;
- }
- _prefetch();
-}
-
-void Journaler::_assimilate_prefetch()
-{
- bool was_readable = readable;
-
- bool got_any = false;
- while (!prefetch_buf.empty()) {
- map<uint64_t,bufferlist>::iterator p = prefetch_buf.begin();
- if (p->first != received_pos) {
- uint64_t gap = p->first - received_pos;
- ldout(cct, 10) << "_assimilate_prefetch gap of " << gap
- << " from received_pos " << received_pos
- << " to first prefetched buffer " << p->first << dendl;
- break;
- }
-
- ldout(cct, 10) << "_assimilate_prefetch " << p->first << "~"
- << p->second.length() << dendl;
- received_pos += p->second.length();
- read_buf.claim_append(p->second);
- assert(received_pos <= requested_pos);
- prefetch_buf.erase(p);
- got_any = true;
- }
-
- if (got_any) {
- ldout(cct, 10) << "_assimilate_prefetch read_buf now " << read_pos << "~"
- << read_buf.length() << ", read pointers " << read_pos
- << "/" << received_pos << "/" << requested_pos
- << dendl;
-
- // Update readability (this will also hit any decode errors resulting
- // from bad data)
- readable = _is_readable();
- }
-
- if ((got_any && !was_readable && readable) || read_pos == write_pos) {
- // readable!
- ldout(cct, 10) << "_finish_read now readable (or at journal end) readable="
- << readable << " read_pos=" << read_pos << " write_pos="
- << write_pos << dendl;
- if (on_readable) {
- C_OnFinisher *f = on_readable;
- on_readable = 0;
- f->complete(0);
- }
- }
-}
-
-void Journaler::_issue_read(uint64_t len)
-{
- // stuck at safe_pos? (this is needed if we are reading the tail of
- // a journal we are also writing to)
- assert(requested_pos <= safe_pos);
- if (requested_pos == safe_pos) {
- ldout(cct, 10) << "_issue_read requested_pos = safe_pos = " << safe_pos
- << ", waiting" << dendl;
- assert(write_pos > requested_pos);
- if (pending_safe.empty()) {
- _flush(NULL);
- }
-
- // Make sure keys of waitfor_safe map are journal entry boundaries.
- // The key we used here is either next_safe_pos or old value of
- // next_safe_pos. next_safe_pos is always set to journal entry
- // boundary.
- auto p = pending_safe.rbegin();
- if (p != pending_safe.rend())
- waitfor_safe[p->second].push_back(new C_RetryRead(this));
- else
- waitfor_safe[next_safe_pos].push_back(new C_RetryRead(this));
- return;
- }
-
- // don't read too much
- if (requested_pos + len > safe_pos) {
- len = safe_pos - requested_pos;
- ldout(cct, 10) << "_issue_read reading only up to safe_pos " << safe_pos
- << dendl;
- }
-
- // go.
- ldout(cct, 10) << "_issue_read reading " << requested_pos << "~" << len
- << ", read pointers " << read_pos << "/" << received_pos
- << "/" << (requested_pos+len) << dendl;
-
- // step by period (object). _don't_ do a single big filer.read()
- // here because it will wait for all object reads to complete before
- // giving us back any data. this way we can process whatever bits
- // come in that are contiguous.
- uint64_t period = get_layout_period();
- while (len > 0) {
- uint64_t e = requested_pos + period;
- e -= e % period;
- uint64_t l = e - requested_pos;
- if (l > len)
- l = len;
- C_Read *c = new C_Read(this, requested_pos, l);
- filer.read(ino, &layout, CEPH_NOSNAP, requested_pos, l, &c->bl, 0,
- wrap_finisher(c), CEPH_OSD_OP_FLAG_FADVISE_DONTNEED);
- requested_pos += l;
- len -= l;
- }
-}
-
-void Journaler::_prefetch()
-{
- ldout(cct, 10) << "_prefetch" << dendl;
- // prefetch
- uint64_t pf;
- if (temp_fetch_len) {
- ldout(cct, 10) << "_prefetch temp_fetch_len " << temp_fetch_len << dendl;
- pf = temp_fetch_len;
- temp_fetch_len = 0;
- } else {
- pf = fetch_len;
- }
-
- uint64_t raw_target = read_pos + pf;
-
- // read full log segments, so increase if necessary
- uint64_t period = get_layout_period();
- uint64_t remainder = raw_target % period;
- uint64_t adjustment = remainder ? period - remainder : 0;
- uint64_t target = raw_target + adjustment;
-
- // don't read past the log tail
- if (target > write_pos)
- target = write_pos;
-
- if (requested_pos < target) {
- uint64_t len = target - requested_pos;
- ldout(cct, 10) << "_prefetch " << pf << " requested_pos " << requested_pos
- << " < target " << target << " (" << raw_target
- << "), prefetching " << len << dendl;
-
- if (pending_safe.empty() && write_pos > safe_pos) {
- // If we are reading and writing the journal, then we may need
- // to issue a flush if one isn't already in progress.
- // Avoid doing a flush every time so that if we do write/read/write/read
- // we don't end up flushing after every write.
- ldout(cct, 10) << "_prefetch: requested_pos=" << requested_pos
- << ", read_pos=" << read_pos
- << ", write_pos=" << write_pos
- << ", safe_pos=" << safe_pos << dendl;
- _do_flush();
- }
-
- _issue_read(len);
- }
-}
-
-
-/*
- * _is_readable() - return true if next entry is ready.
- */
-bool Journaler::_is_readable()
-{
- // anything to read?
- if (read_pos == write_pos)
- return false;
-
- // Check if the retrieve bytestream has enough for an entry
- uint64_t need;
- if (journal_stream.readable(read_buf, &need)) {
- return true;
- }
-
- ldout (cct, 10) << "_is_readable read_buf.length() == " << read_buf.length()
- << ", but need " << need << " for next entry; fetch_len is "
- << fetch_len << dendl;
-
- // partial fragment at the end?
- if (received_pos == write_pos) {
- ldout(cct, 10) << "is_readable() detected partial entry at tail, "
- "adjusting write_pos to " << read_pos << dendl;
-
- // adjust write_pos
- prezeroing_pos = prezero_pos = write_pos = flush_pos = safe_pos = next_safe_pos = read_pos;
- assert(write_buf.length() == 0);
- assert(waitfor_safe.empty());
-
- // reset read state
- requested_pos = received_pos = read_pos;
- read_buf.clear();
-
- // FIXME: truncate on disk?
-
- return false;
- }
-
- if (need > fetch_len) {
- temp_fetch_len = need;
- ldout(cct, 10) << "_is_readable noting temp_fetch_len " << temp_fetch_len
- << dendl;
- }
-
- ldout(cct, 10) << "_is_readable: not readable, returning false" << dendl;
- return false;
-}
-
-/*
- * is_readable() - kickstart prefetch, too
- */
-bool Journaler::is_readable()
-{
- lock_guard l(lock);
-
- if (error != 0) {
- return false;
- }
-
- bool r = readable;
- _prefetch();
- return r;
-}
-
-class Journaler::C_EraseFinish : public Context {
- Journaler *journaler;
- C_OnFinisher *completion;
- public:
- C_EraseFinish(Journaler *j, C_OnFinisher *c) : journaler(j), completion(c) {}
- void finish(int r) override {
- journaler->_finish_erase(r, completion);
- }
-};
-
-/**
- * Entirely erase the journal, including header. For use when you
- * have already made a copy of the journal somewhere else.
- */
-void Journaler::erase(Context *completion)
-{
- lock_guard l(lock);
-
- // Async delete the journal data
- uint64_t first = trimmed_pos / get_layout_period();
- uint64_t num = (write_pos - trimmed_pos) / get_layout_period() + 2;
- filer.purge_range(ino, &layout, SnapContext(), first, num,
- ceph::real_clock::now(), 0,
- wrap_finisher(new C_EraseFinish(
- this, wrap_finisher(completion))));
-
- // We will not start the operation to delete the header until
- // _finish_erase has seen the data deletion succeed: otherwise if
- // there was an error deleting data we might prematurely delete the
- // header thereby lose our reference to the data.
-}
-
-void Journaler::_finish_erase(int data_result, C_OnFinisher *completion)
-{
- lock_guard l(lock);
-
- if (data_result == 0) {
- // Async delete the journal header
- filer.purge_range(ino, &layout, SnapContext(), 0, 1,
- ceph::real_clock::now(),
- 0, wrap_finisher(completion));
- } else {
- lderr(cct) << "Failed to delete journal " << ino << " data: "
- << cpp_strerror(data_result) << dendl;
- completion->complete(data_result);
- }
-}
-
-/* try_read_entry(bl)
- * read entry into bl if it's ready.
- * otherwise, do nothing.
- */
-bool Journaler::try_read_entry(bufferlist& bl)
-{
- lock_guard l(lock);
-
- if (!readable) {
- ldout(cct, 10) << "try_read_entry at " << read_pos << " not readable"
- << dendl;
- return false;
- }
-
- uint64_t start_ptr;
- size_t consumed;
- try {
- consumed = journal_stream.read(read_buf, &bl, &start_ptr);
- if (stream_format >= JOURNAL_FORMAT_RESILIENT) {
- assert(start_ptr == read_pos);
- }
- } catch (const buffer::error &e) {
- lderr(cct) << __func__ << ": decode error from journal_stream" << dendl;
- error = -EINVAL;
- return false;
- }
-
- ldout(cct, 10) << "try_read_entry at " << read_pos << " read "
- << read_pos << "~" << consumed << " (have "
- << read_buf.length() << ")" << dendl;
-
- read_pos += consumed;
- try {
- // We were readable, we might not be any more
- readable = _is_readable();
- } catch (const buffer::error &e) {
- lderr(cct) << __func__ << ": decode error from _is_readable" << dendl;
- error = -EINVAL;
- return false;
- }
-
- // prefetch?
- _prefetch();
- return true;
-}
-
-void Journaler::wait_for_readable(Context *onreadable)
-{
- lock_guard l(lock);
- if (stopping) {
- finisher->queue(onreadable, -EAGAIN);
- return;
- }
-
- assert(on_readable == 0);
- if (!readable) {
- ldout(cct, 10) << "wait_for_readable at " << read_pos << " onreadable "
- << onreadable << dendl;
- on_readable = wrap_finisher(onreadable);
- } else {
- // race with OSD reply
- finisher->queue(onreadable, 0);
- }
-}
-
-bool Journaler::have_waiter() const
-{
- return on_readable != nullptr;
-}
-
-
-
-
-/***************** TRIMMING *******************/
-
-
-class Journaler::C_Trim : public Context {
- Journaler *ls;
- uint64_t to;
-public:
- C_Trim(Journaler *l, int64_t t) : ls(l), to(t) {}
- void finish(int r) override {
- ls->_finish_trim(r, to);
- }
-};
-
-void Journaler::trim()
-{
- lock_guard l(lock);
- _trim();
-}
-
-void Journaler::_trim()
-{
- assert(!readonly);
- uint64_t period = get_layout_period();
- uint64_t trim_to = last_committed.expire_pos;
- trim_to -= trim_to % period;
- ldout(cct, 10) << "trim last_commited head was " << last_committed
- << ", can trim to " << trim_to
- << dendl;
- if (trim_to == 0 || trim_to == trimming_pos) {
- ldout(cct, 10) << "trim already trimmed/trimming to "
- << trimmed_pos << "/" << trimming_pos << dendl;
- return;
- }
-
- if (trimming_pos > trimmed_pos) {
- ldout(cct, 10) << "trim already trimming atm, try again later. "
- "trimmed/trimming is " << trimmed_pos << "/" << trimming_pos << dendl;
- return;
- }
-
- // trim
- assert(trim_to <= write_pos);
- assert(trim_to <= expire_pos);
- assert(trim_to > trimming_pos);
- ldout(cct, 10) << "trim trimming to " << trim_to
- << ", trimmed/trimming/expire are "
- << trimmed_pos << "/" << trimming_pos << "/" << expire_pos
- << dendl;
-
- // delete range of objects
- uint64_t first = trimming_pos / period;
- uint64_t num = (trim_to - trimming_pos) / period;
- SnapContext snapc;
- filer.purge_range(ino, &layout, snapc, first, num,
- ceph::real_clock::now(), 0,
- wrap_finisher(new C_Trim(this, trim_to)));
- trimming_pos = trim_to;
-}
-
-void Journaler::_finish_trim(int r, uint64_t to)
-{
- lock_guard l(lock);
-
- assert(!readonly);
- ldout(cct, 10) << "_finish_trim trimmed_pos was " << trimmed_pos
- << ", trimmed/trimming/expire now "
- << to << "/" << trimming_pos << "/" << expire_pos
- << dendl;
- if (r < 0 && r != -ENOENT) {
- lderr(cct) << "_finish_trim got " << cpp_strerror(r) << dendl;
- handle_write_error(r);
- return;
- }
-
- assert(r >= 0 || r == -ENOENT);
-
- assert(to <= trimming_pos);
- assert(to > trimmed_pos);
- trimmed_pos = to;
-}
-
-void Journaler::handle_write_error(int r)
-{
- // lock is locked
-
- lderr(cct) << "handle_write_error " << cpp_strerror(r) << dendl;
- if (on_write_error) {
- on_write_error->complete(r);
- on_write_error = NULL;
- called_write_error = true;
- } else if (called_write_error) {
- /* We don't call error handler more than once, subsequent errors
- * are dropped -- this is okay as long as the error handler does
- * something dramatic like respawn */
- lderr(cct) << __func__ << ": multiple write errors, handler already called"
- << dendl;
- } else {
- assert(0 == "unhandled write error");
- }
-}
-
-
-/**
- * Test whether the 'read_buf' byte stream has enough data to read
- * an entry
- *
- * sets 'next_envelope_size' to the number of bytes needed to advance (enough
- * to get the next header if header was unavailable, or enough to get the whole
- * next entry if the header was available but the body wasn't).
- */
-bool JournalStream::readable(bufferlist &read_buf, uint64_t *need) const
-{
- assert(need != NULL);
-
- uint32_t entry_size = 0;
- uint64_t entry_sentinel = 0;
- bufferlist::iterator p = read_buf.begin();
-
- // Do we have enough data to decode an entry prefix?
- if (format >= JOURNAL_FORMAT_RESILIENT) {
- *need = sizeof(entry_size) + sizeof(entry_sentinel);
- } else {
- *need = sizeof(entry_size);
- }
- if (read_buf.length() >= *need) {
- if (format >= JOURNAL_FORMAT_RESILIENT) {
- ::decode(entry_sentinel, p);
- if (entry_sentinel != sentinel) {
- throw buffer::malformed_input("Invalid sentinel");
- }
- }
-
- ::decode(entry_size, p);
- } else {
- return false;
- }
-
- // Do we have enough data to decode an entry prefix, payload and suffix?
- if (format >= JOURNAL_FORMAT_RESILIENT) {
- *need = JOURNAL_ENVELOPE_RESILIENT + entry_size;
- } else {
- *need = JOURNAL_ENVELOPE_LEGACY + entry_size;
- }
- if (read_buf.length() >= *need) {
- return true; // No more bytes needed
- }
-
- return false;
-}
-
-
-/**
- * Consume one entry from a journal byte stream 'from', splicing a
- * serialized LogEvent blob into 'entry'.
- *
- * 'entry' must be non null and point to an empty bufferlist.
- *
- * 'from' must contain sufficient valid data (i.e. readable is true).
- *
- * 'start_ptr' will be set to the entry's start pointer, if the collection
- * format provides it. It may not be null.
- *
- * @returns The number of bytes consumed from the `from` byte stream. Note
- * that this is not equal to the length of `entry`, which contains
- * the inner serialized LogEvent and not the envelope.
- */
-size_t JournalStream::read(bufferlist &from, bufferlist *entry,
- uint64_t *start_ptr)
-{
- assert(start_ptr != NULL);
- assert(entry != NULL);
- assert(entry->length() == 0);
-
- uint32_t entry_size = 0;
-
- // Consume envelope prefix: entry_size and entry_sentinel
- bufferlist::iterator from_ptr = from.begin();
- if (format >= JOURNAL_FORMAT_RESILIENT) {
- uint64_t entry_sentinel = 0;
- ::decode(entry_sentinel, from_ptr);
- // Assertion instead of clean check because of precondition of this
- // fn is that readable() already passed
- assert(entry_sentinel == sentinel);
- }
- ::decode(entry_size, from_ptr);
-
- // Read out the payload
- from_ptr.copy(entry_size, *entry);
-
- // Consume the envelope suffix (start_ptr)
- if (format >= JOURNAL_FORMAT_RESILIENT) {
- ::decode(*start_ptr, from_ptr);
- } else {
- *start_ptr = 0;
- }
-
- // Trim the input buffer to discard the bytes we have consumed
- from.splice(0, from_ptr.get_off());
-
- return from_ptr.get_off();
-}
-
-
-/**
- * Append one entry
- */
-size_t JournalStream::write(bufferlist &entry, bufferlist *to,
- uint64_t const &start_ptr)
-{
- assert(to != NULL);
-
- uint32_t const entry_size = entry.length();
- if (format >= JOURNAL_FORMAT_RESILIENT) {
- ::encode(sentinel, *to);
- }
- ::encode(entry_size, *to);
- to->claim_append(entry);
- if (format >= JOURNAL_FORMAT_RESILIENT) {
- ::encode(start_ptr, *to);
- }
-
- if (format >= JOURNAL_FORMAT_RESILIENT) {
- return JOURNAL_ENVELOPE_RESILIENT + entry_size;
- } else {
- return JOURNAL_ENVELOPE_LEGACY + entry_size;
- }
-}
-
-/**
- * set write error callback
- *
- * Set a callback/context to trigger if we get a write error from
- * the objecter. This may be from an explicit request (e.g., flush)
- * or something async the journaler did on its own (e.g., journal
- * header update).
- *
- * It is only used once; if the caller continues to use the
- * Journaler and wants to hear about errors, it needs to reset the
- * error_handler.
- *
- * @param c callback/context to trigger on error
- */
-void Journaler::set_write_error_handler(Context *c) {
- lock_guard l(lock);
- assert(!on_write_error);
- on_write_error = wrap_finisher(c);
- called_write_error = false;
-}
-
-
-/**
- * Wrap a context in a C_OnFinisher, if it is non-NULL
- *
- * Utility function to avoid lots of error-prone and verbose
- * NULL checking on contexts passed in.
- */
-C_OnFinisher *Journaler::wrap_finisher(Context *c)
-{
- if (c != NULL) {
- return new C_OnFinisher(c, finisher);
- } else {
- return NULL;
- }
-}
-
-void Journaler::shutdown()
-{
- lock_guard l(lock);
-
- ldout(cct, 1) << __func__ << dendl;
-
- readable = false;
- stopping = true;
-
- // Kick out anyone reading from journal
- error = -EAGAIN;
- if (on_readable) {
- C_OnFinisher *f = on_readable;
- on_readable = 0;
- f->complete(-EAGAIN);
- }
-
- finish_contexts(cct, waitfor_recover, -ESHUTDOWN);
-
- std::map<uint64_t, std::list<Context*> >::iterator i;
- for (i = waitfor_safe.begin(); i != waitfor_safe.end(); ++i) {
- finish_contexts(cct, i->second, -EAGAIN);
- }
- waitfor_safe.clear();
-}
-
Code Review / stor4nfv.git / blobdiff