The standby logic used to be pretty dependent on the work requeueing
behavior that changed when we switched to WQ_NON_REENTRANT. It was also
very fragile.
Restructure things so that:
- We clear WRITE_PENDING when we set STANDBY. This ensures we will
requeue work when we wake up later.
- con_work backs off if STANDBY is set. There is nothing to do if we are
in standby.
- clear_standby() helper is called by both con_send() and con_keepalive(),
the two actions that can wake us up again. Move the connect_seq++
logic here.
Signed-off-by: Sage Weil <sage@newdream.net>
With commit f363e45f we replaced a bunch of hacky workqueue mutual
exclusion logic with the WQ_NON_REENTRANT flag. One pieces of fallout is
that the exponential backoff breaks in certain cases:
* con_work attempts to connect.
* we get an immediate failure, and the socket state change handler queues
immediate work.
* con_work calls con_fault, we decide to back off, but can't queue delayed
work.
In this case, we add a BACKOFF bit to make con_work reschedule delayed work
next time it runs (which should be immediately).
Signed-off-by: Sage Weil <sage@newdream.net>
If we mark the connection CLOSED we will give up trying to reconnect to
this server instance. That is appropriate for things like a protocol
version mismatch that won't change until the server is restarted, at which
point we'll get a new addr and reconnect. An authorization failure like
this is probably due to the server not properly rotating it's secret keys,
however, and should be treated as transient so that the normal backoff and
retry behavior kicks in.
Signed-off-by: Sage Weil <sage@newdream.net>
Pass errors from writing to the socket up the stack. If we get -EAGAIN,
return 0 from the helper to simplify the callers' checks.
Signed-off-by: Sage Weil <sage@newdream.net>
If we get EAGAIN when trying to read from the socket, it is not an error.
Return 0 from the helper in this case to simplify the error handling cases
in the caller (indirectly, try_read).
Fix try_read to pass any error to it's caller (con_work) instead of almost
always returning 0. This let's us respond to things like socket
disconnects.
Signed-off-by: Sage Weil <sage@newdream.net>
ceph messenger code does a rather complex dancing around multithread
workqueue to make sure the same work item isn't executed concurrently
on different CPUs. This restriction can be provided by workqueue with
WQ_NON_REENTRANT.
Make ceph_msgr_wq non-reentrant workqueue with the default concurrency
level and remove the QUEUED/BUSY logic.
* This removes backoff handling in con_work() but it couldn't reliably
block execution of con_work() to begin with - queue_con() can be
called after the work started but before BUSY is set. It seems that
it was an optimization for a rather cold path and can be safely
removed.
* The number of concurrent work items is bound by the number of
connections and connetions are independent from each other. With
the default concurrency level, different connections will be
executed independently.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Sage Weil <sage@newdream.net>
Cc: ceph-devel@vger.kernel.org
Signed-off-by: Sage Weil <sage@newdream.net>
The alignment used for reading data into or out of pages used to be taken
from the data_off field in the message header. This only worked as long
as the page alignment matched the object offset, breaking direct io to
non-page aligned offsets.
Instead, explicitly specify the page alignment next to the page vector
in the ceph_msg struct, and use that instead of the message header (which
probably shouldn't be trusted). The alloc_msg callback is responsible for
filling in this field properly when it sets up the page vector.
Signed-off-by: Sage Weil <sage@newdream.net>
If the client gets out of sync with the server message sequence number, we
normally skip low seq messages (ones we already received). The skip code
was also incrementing the expected seq, such that all subsequent messages
also appeared old and got skipped, and an eventual timeout on the osd
connection. This resulted in some lagging requests and console messages
like
[233480.882885] ceph: skipping osd22 10.138.138.13:6804 seq 2016, expected 2017
[233480.882919] ceph: skipping osd22 10.138.138.13:6804 seq 2017, expected 2018
[233480.882963] ceph: skipping osd22 10.138.138.13:6804 seq 2018, expected 2019
[233480.883488] ceph: skipping osd22 10.138.138.13:6804 seq 2019, expected 2020
[233485.219558] ceph: skipping osd22 10.138.138.13:6804 seq 2020, expected 2021
[233485.906595] ceph: skipping osd22 10.138.138.13:6804 seq 2021, expected 2022
[233490.379536] ceph: skipping osd22 10.138.138.13:6804 seq 2022, expected 2023
[233495.523260] ceph: skipping osd22 10.138.138.13:6804 seq 2023, expected 2024
[233495.923194] ceph: skipping osd22 10.138.138.13:6804 seq 2024, expected 2025
[233500.534614] ceph: tid 6023602 timed out on osd22, will reset osd
Reported-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sage Weil <sage@newdream.net>
This factors out protocol and low-level storage parts of ceph into a
separate libceph module living in net/ceph and include/linux/ceph. This
is mostly a matter of moving files around. However, a few key pieces
of the interface change as well:
- ceph_client becomes ceph_fs_client and ceph_client, where the latter
captures the mon and osd clients, and the fs_client gets the mds client
and file system specific pieces.
- Mount option parsing and debugfs setup is correspondingly broken into
two pieces.
- The mon client gets a generic handler callback for otherwise unknown
messages (mds map, in this case).
- The basic supported/required feature bits can be expanded (and are by
ceph_fs_client).
No functional change, aside from some subtle error handling cases that got
cleaned up in the refactoring process.
Signed-off-by: Sage Weil <sage@newdream.net>
