common/Finisher: add queue(list<Context*>&)

Signed-off-by: Samuel Just <sam.just@inktank.com>
osd_types: add pg_log_t::rollback_info_trimmed_to

Signed-off-by: Samuel Just <sam.just@inktank.com>
PGLog: initialize complete_to

Signed-off-by: Samuel Just <sam.just@inktank.com>
mds: pass finish context to MDlog::submit_entry()

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
mds: add get_metablob() to log events

later commits will use it to get EMetaBlob and update EMetaBlob's
event sequence number.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
mds: introduce sequence number for log events

Use the sequence number to index log segments. Later commit will defer
encoding/submitting log events to separate thread, log events' offsets
are unknown before they are encoded.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
mds: print sequence number of log segment
os/: add async flush_commit() method to Sequencer and implementations

Signed-off-by: Samuel Just <sam.just@inktank.com>
PG: add machinery to temporarily buffer outgoing recovery messages

Signed-off-by: Samuel Just <sam.just@inktank.com>
PG: block outgoing peering messages until the last interval is durable

Signed-off-by: Samuel Just <sam.just@inktank.com>
Merge remote-tracking branch 'upstream/master' into wip-7999-master

Conflicts:
	src/os/KeyValueStore.h
PGLog: fix logging whitespace in trim

Signed-off-by: Samuel Just <sam.just@inktank.com>
PGLog: add rollback_info_trimmed_to_riter to IndexedLog and use in PG

Signed-off-by: Samuel Just <sam.just@inktank.com>
osd/: plumb rollback_trim_to through interfaces and messages

We simply trim the roll back info up to min_last_complete_ondisk
since we cannot correctly rollback past that point anyway!

ReplicatedPG
-> PGBackend::submit_transaction
-> Backend messages
-> PGBackend::Listener::log_operation
-> append_log

Signed-off-by: Samuel Just <sam.just@inktank.com>
osd/: in scrub, check for and remove obsolete rollback objs

Signed-off-by: Samuel Just <sam.just@inktank.com>
Merge remote-tracking branch 'upstream/master' into wip-8438-master

Conflicts:
	src/osd/ECMsgTypes.cc
doc: dev: cache-pool.rst: fix typo s/objets/objects/

Signed-off-by: Joao Eduardo Luis <joao.luis@inktank.com>
test_librbd_fsx: use private RNG context

It is at the core of fsx to be able to reproduce the exact op sequence
that lead to a failure.  Use reentrant glibc RNG functions to make sure
that nothing else has to chance to mess up the sequence.

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
map-unmap.sh: drop the get_id() logic

Take advantage of the fact that 'rbd map' will now talk to udev and
output the device that got assigned by the kernel to the newly created
mapping.  Drop the get_id() cruft, udevadm settle and chown calls.

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
map-unmap.sh: fail if 'rbd rm' fails

Fail if 'rbd rm' fails - most probably it'd fail with "image still has
watchers" and in that case it's a bug in the kernel client which we do
want to notice.  Also nuke the trap-based error handling - cleanup() is
half-baked and not really necessary here.

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>