Commit Graph

232 Commits

Author SHA1 Message Date
Sage Weil
4740a623d2 libceph: change ceph_con_in_msg_alloc convention to be less weird
This function's calling convention is very limiting.  In particular,
we can't return any error other than ENOMEM (and only implicitly),
which is a problem (see next patch).

Instead, return an normal 0 or error code, and make the skip a pointer
output parameter.  Drop the useless in_hdr argument (we have the con
pointer).

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30 18:19:30 -07:00
Sage Weil
8636ea672f libceph: avoid dropping con mutex before fault
The ceph_fault() function takes the con mutex, so we should avoid
dropping it before calling it.  This fixes a potential race with
another thread calling ceph_con_close(), or _open(), or similar (we
don't reverify con->state after retaking the lock).

Add annotation so that lockdep realizes we will drop the mutex before
returning.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30 18:17:13 -07:00
Sage Weil
7b862e07b1 libceph: verify state after retaking con lock after dispatch
We drop the con mutex when delivering a message.  When we retake the
lock, we need to verify we are still in the OPEN state before
preparing to read the next tag, or else we risk stepping on a
connection that has been closed.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30 18:16:56 -07:00
Sage Weil
4f471e4a9c libceph: revoke mon_client messages on session restart
Revoke all mon_client messages when we shut down the old connection.
This is mostly moot since we are re-using the same ceph_connection,
but it is cleaner.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30 18:16:40 -07:00
Sage Weil
8007b8d626 libceph: fix handling of immediate socket connect failure
If the connect() call immediately fails such that sock == NULL, we
still need con_close_socket() to reset our socket state to CLOSED.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30 18:16:16 -07:00
Sage Weil
756a16a5d5 libceph: be less chatty about stray replies
There are many (normal) conditions that can lead to us getting
unexpected replies, include cluster topology changes, osd failures,
and timeouts.  There's no need to spam the console about it.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30 18:16:03 -07:00
Sage Weil
43c7427d10 libceph: clear all flags on con_close
Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30 18:16:02 -07:00
Sage Weil
4a86169208 libceph: clean up con flags
Rename flags with CON_FLAG prefix, move the definitions into the c file,
and (better) document their meaning.

Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30 18:16:01 -07:00
Sage Weil
8dacc7da69 libceph: replace connection state bits with states
Use a simple set of 6 enumerated values for the socket states (CON_STATE_*)
and use those instead of the state bits.  All of the con->state checks are
now under the protection of the con mutex, so this is safe.  It also
simplifies many of the state checks because we can check for anything other
than the expected state instead of various bits for races we can think of.

This appears to hold up well to stress testing both with and without socket
failure injection on the server side.

Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30 18:16:00 -07:00
Sage Weil
d7353dd5aa libceph: drop unnecessary CLOSED check in socket state change callback
If we are CLOSED, the socket is closed and we won't get these.

Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30 18:15:59 -07:00
Sage Weil
ee76e0736d libceph: close socket directly from ceph_con_close()
It is simpler to do this immediately, since we already hold the con mutex.
It also avoids the need to deal with a not-quite-CLOSED socket in con_work.

Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30 18:15:58 -07:00
Sage Weil
2e8cb10063 libceph: drop gratuitous socket close calls in con_work
If the state is CLOSED or OPENING, we shouldn't have a socket.

Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30 18:15:58 -07:00
Sage Weil
a59b55a602 libceph: move ceph_con_send() closed check under the con mutex
Take the con mutex before checking whether the connection is closed to
avoid racing with someone else closing it.

Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30 18:15:57 -07:00
Sage Weil
00650931e5 libceph: move msgr clear_standby under con mutex protection
Avoid dropping and retaking con->mutex in the ceph_con_send() case by
leaving locking up to the caller.

Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30 18:15:56 -07:00
Sage Weil
3b5ede07b5 libceph: fix fault locking; close socket on lossy fault
If we fault on a lossy connection, we should still close the socket
immediately, and do so under the con mutex.

We should also take the con mutex before printing out the state bits in
the debug output.

Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30 18:15:55 -07:00
Jiaju Zhang
048a9d2d06 libceph: trivial fix for the incorrect debug output
This is a trivial fix for the debug output, as it is inconsistent
with the function name so may confuse people when debugging.

[elder@inktank.com: switched to use __func__]

Signed-off-by: Jiaju Zhang <jjzhang@suse.de>
Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30 18:15:36 -07:00
Sage Weil
85effe183d libceph: reset connection retry on successfully negotiation
We exponentially back off when we encounter connection errors.  If several
errors accumulate, we will eventually wait ages before even trying to
reconnect.

Fix this by resetting the backoff counter after a successful negotiation/
connection with the remote node.  Fixes ceph issue #2802.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30 18:15:34 -07:00
Sage Weil
5469155f2b libceph: protect ceph_con_open() with mutex
Take the con mutex while we are initiating a ceph open.  This is necessary
because the may have previously been in use and then closed, which could
result in a racing workqueue running con_work().

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30 18:15:33 -07:00
Sage Weil
a410702697 libceph: (re)initialize bio_iter on start of message receive
Previously, we were opportunistically initializing the bio_iter if it
appeared to be uninitialized in the middle of the read path.  The problem
is that a sequence like:

 - start reading message
 - initialize bio_iter
 - read half a message
 - messenger fault, reconnect
 - restart reading message
 - ** bio_iter now non-NULL, not reinitialized **
 - read past end of bio, crash

Instead, initialize the bio_iter unconditionally when we allocate/claim
the message for read.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
2012-07-30 18:15:31 -07:00
Sage Weil
6194ea895e libceph: resubmit linger ops when pg mapping changes
The linger op registration (i.e., watch) modifies the object state.  As
such, the OSD will reply with success if it has already applied without
doing the associated side-effects (setting up the watch session state).
If we lose the ACK and resubmit, we will see success but the watch will not
be correctly registered and we won't get notifies.

To fix this, always resubmit the linger op with a new tid.  We accomplish
this by re-registering as a linger (i.e., 'registered') if we are not yet
registered.  Then the second loop will treat this just like a normal
case of re-registering.

This mirrors a similar fix on the userland ceph.git, commit 5dd68b95, and
ceph bug #2796.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
2012-07-30 18:15:31 -07:00
Sage Weil
8c50c81756 libceph: fix mutex coverage for ceph_con_close
Hold the mutex while twiddling all of the state bits to avoid possible
races.  While we're here, make not of why we cannot close the socket
directly.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
2012-07-30 18:15:30 -07:00
Sage Weil
3a140a0d5c libceph: report socket read/write error message
We need to set error_msg to something useful before calling ceph_fault();
do so here for try_{read,write}().  This is more informative than

libceph: osd0 192.168.106.220:6801 (null)

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
2012-07-30 18:15:29 -07:00
Sage Weil
546f04ef71 libceph: support crush tunables
The server side recently added support for tuning some magic
crush variables. Decode these variables if they are present, or use the
default values if they are not present.

Corresponds to ceph.git commit 89af369c25f274fe62ef730e5e8aad0c54f1e5a5.

Signed-off-by: caleb miles <caleb.miles@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
2012-07-30 18:15:23 -07:00
Sage Weil
1fe60e51a3 libceph: move feature bits to separate header
This is simply cleanup that will keep things more closely synced with the
userland code.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
2012-07-30 16:23:22 -07:00
Guanjun He
a2a3258417 libceph: prevent the race of incoming work during teardown
Add an atomic variable 'stopping' as flag in struct ceph_messenger,
set this flag to 1 in function ceph_destroy_client(), and add the condition code
in function ceph_data_ready() to test the flag value, if true(1), just return.

Signed-off-by: Guanjun He <gjhe@suse.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-30 09:29:53 -07:00
Sage Weil
a16cb1f707 libceph: fix messenger retry
In ancient times, the messenger could both initiate and accept connections.
An artifact if that was data structures to store/process an incoming
ceph_msg_connect request and send an outgoing ceph_msg_connect_reply.
Sadly, the negotiation code was referencing those structures and ignoring
important information (like the peer's connect_seq) from the correct ones.

Among other things, this fixes tight reconnect loops where the server sends
RETRY_SESSION and we (the client) retries with the same connect_seq as last
time.  This bug pretty easily triggered by injecting socket failures on the
MDS and running some fs workload like workunits/direct_io/test_sync_io.

Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30 09:29:52 -07:00
Sage Weil
cd43045c2d libceph: initialize rb, list nodes in ceph_osd_request
These don't strictly need to be initialized based on how they are used, but
it is good practice to do so.

Reported-by: Alex Elder <elder@inktank.com>
Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30 09:29:51 -07:00
Sage Weil
d50b409fb8 libceph: initialize msgpool message types
Initialize the type field for messages in a msgpool.  The caller was doing
this for osd ops, but not for the reply messages.

Reported-by: Alex Elder <elder@inktank.com>
Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30 09:29:50 -07:00
Sage Weil
fbb85a478f libceph: allow sock transition from CONNECTING to CLOSED
It is possible to close a socket that is in the OPENING state.  For
example, it can happen if ceph_con_close() is called on the con before
the TCP connection is established.  con_work() will come around and shut
down the socket.

Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:39 -07:00
Sage Weil
735a72ef95 libceph: initialize mon_client con only once
Do not re-initialize the con on every connection attempt.  When we
ceph_con_close, there may still be work queued on the socket (e.g., to
close it), and re-initializing will clobber the work_struct state.

Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:38 -07:00
Sage Weil
b7a9e5dd40 libceph: set peer name on con_open, not init
The peer name may change on each open attempt, even when the connection is
reused.

Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:35 -07:00
Alex Elder
bc18f4b1c8 libceph: add some fine ASCII art
Sage liked the state diagram I put in my commit description so
I'm putting it in with the code.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:32 -07:00
Alex Elder
5821bd8ccd libceph: small changes to messenger.c
This patch gathers a few small changes in "net/ceph/messenger.c":
  out_msg_pos_next()
    - small logic change that mostly affects indentation
  write_partial_msg_pages().
    - use a local variable trail_off to represent the offset into
      a message of the trail portion of the data (if present)
    - once we are in the trail portion we will always be there, so we
      don't always need to check against our data position
    - avoid computing len twice after we've reached the trail
    - get rid of the variable tmpcrc, which is not needed
    - trail_off and trail_len never change so mark them const
    - update some comments
  read_partial_message_bio()
    - bio_iovec_idx() will never return an error, so don't bother
      checking for it

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:31 -07:00
Alex Elder
7593af920b libceph: distinguish two phases of connect sequence
Currently a ceph connection enters a "CONNECTING" state when it
begins the process of (re-)connecting with its peer.  Once the two
ends have successfully exchanged their banner and addresses, an
additional NEGOTIATING bit is set in the ceph connection's state to
indicate the connection information exhange has begun.  The
CONNECTING bit/state continues to be set during this phase.

Rather than have the CONNECTING state continue while the NEGOTIATING
bit is set, interpret these two phases as distinct states.  In other
words, when NEGOTIATING is set, clear CONNECTING.  That way only
one of them will be active at a time.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:30 -07:00
Alex Elder
ab166d5aa3 libceph: separate banner and connect writes
There are two phases in the process of linking together the two ends
of a ceph connection.  The first involves exchanging a banner and
IP addresses, and if that is successful a second phase exchanges
some detail about each side's connection capabilities.

When initiating a connection, the client side now queues to send
its information for both phases of this process at the same time.
This is probably a bit more efficient, but it is slightly messier
from a layering perspective in the code.

So rearrange things so that the client doesn't send the connection
information until it has received and processed the response in the
initial banner phase (in process_banner()).

Move the code (in the (con->sock == NULL) case in try_write()) that
prepares for writing the connection information, delaying doing that
until the banner exchange has completed.  Move the code that begins
the transition to this second "NEGOTIATING" phase out of
process_banner() and into its caller, so preparing to write the
connection information and preparing to read the response are
adjacent to each other.

Finally, preparing to write the connection information now requires
the output kvec to be reset in all cases, so move that into the
prepare_write_connect() and delete it from all callers.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:29 -07:00
Alex Elder
e27947c767 libceph: define and use an explicit CONNECTED state
There is no state explicitly defined when a ceph connection is fully
operational.  So define one.

It's set when the connection sequence completes successfully, and is
cleared when the connection gets closed.

Be a little more careful when examining the old state when a socket
disconnect event is reported.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:27 -07:00
Alex Elder
3ec50d1868 libceph: clear NEGOTIATING when done
A connection state's NEGOTIATING bit gets set while in CONNECTING
state after we have successfully exchanged a ceph banner and IP
addresses with the connection's peer (the server).  But that bit
is not cleared again--at least not until another connection attempt
is initiated.

Instead, clear it as soon as the connection is fully established.
Also, clear it when a socket connection gets prematurely closed
in the midst of establishing a ceph connection (in case we had
reached the point where it was set).

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:26 -07:00
Alex Elder
bb9e6bba5d libceph: clear CONNECTING in ceph_con_close()
A connection that is closed will no longer be connecting.  So
clear the CONNECTING state bit in ceph_con_close().  Similarly,
if the socket has been closed we no longer are in connecting
state (a new connect sequence will need to be initiated).

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:24 -07:00
Alex Elder
456ea46865 libceph: don't touch con state in con_close_socket()
In con_close_socket(), a connection's SOCK_CLOSED flag gets set and
then cleared while its shutdown method is called and its reference
gets dropped.

Previously, that flag got set only if it had not already been set,
so setting it in con_close_socket() might have prevented additional
processing being done on a socket being shut down.  We no longer set
SOCK_CLOSED in the socket event routine conditionally, so setting
that bit here no longer provides whatever benefit it might have
provided before.

A race condition could still leave the SOCK_CLOSED bit set even
after we've issued the call to con_close_socket(), so we still clear
that bit after shutting the socket down.  Add a comment explaining
the reason for this.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:23 -07:00
Alex Elder
d65c9e0b9e libceph: just set SOCK_CLOSED when state changes
When a TCP_CLOSE or TCP_CLOSE_WAIT event occurs, the SOCK_CLOSED
connection flag bit is set, and if it had not been previously set
queue_con() is called to ensure con_work() will get a chance to
handle the changed state.

con_work() atomically checks--and if set, clears--the SOCK_CLOSED
bit if it was set.  This means that even if the bit were set
repeatedly, the related processing in con_work() only gets called
once per transition of the bit from 0 to 1.

What's important then is that we ensure con_work() gets called *at
least* once when a socket close event occurs, not that it gets
called *exactly* once.

The work queue mechanism already takes care of queueing work
only if it is not already queued, so there's no need for us
to call queue_con() conditionally.

So this patch just makes it so the SOCK_CLOSED flag gets set
unconditionally in ceph_sock_state_change().

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:22 -07:00
Alex Elder
188048bce3 libceph: don't change socket state on sock event
Currently the socket state change event handler records an error
message on a connection to distinguish a close while connecting from
a close while a connection was already established.

Changing connection information during handling of a socket event is
not very clean, so instead move this assignment inside con_work(),
where it can be done during normal connection-level processing (and
under protection of the connection mutex as well).

Move the handling of a socket closed event up to the top of the
processing loop in con_work(); there's no point in handling backoff
etc. if we have a newly-closed socket to take care of.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:20 -07:00
Alex Elder
a8d00e3cde libceph: SOCK_CLOSED is a flag, not a state
The following commit changed it so SOCK_CLOSED bit was stored in
a connection's new "flags" field rather than its "state" field.

    libceph: start separating connection flags from state
    commit 928443cd

That bit is used in con_close_socket() to protect against setting an
error message more than once in the socket event handler function.

Unfortunately, the field being operated on in that function was not
updated to be "flags" as it should have been.  This fixes that
error.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:19 -07:00
Alex Elder
abdaa6a849 libceph: don't use bio_iter as a flag
Recently a bug was fixed in which the bio_iter field in a ceph
message was not being properly re-initialized when a message got
re-transmitted:
    commit 43643528cc
    Author: Yan, Zheng <zheng.z.yan@intel.com>
    rbd: Clear ceph_msg->bio_iter for retransmitted message

We are now only initializing the bio_iter field when we are about to
start to write message data (in prepare_write_message_data()),
rather than every time we are attempting to write any portion of the
message data (in write_partial_msg_pages()).  This means we no
longer need to use the msg->bio_iter field as a flag.

So just don't do that any more.  Trust prepare_write_message_data()
to ensure msg->bio_iter is properly initialized, every time we are
about to begin writing (or re-writing) a message's bio data.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:18 -07:00
Alex Elder
572c588eda libceph: move init of bio_iter
If a message has a non-null bio pointer, its bio_iter field is
initialized in write_partial_msg_pages() if this has not been done
already.  This is really a one-time setup operation for sending a
message's (bio) data, so move that initialization code into
prepare_write_message_data() which serves that purpose.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:16 -07:00
Alex Elder
df6ad1f973 libceph: move init_bio_*() functions up
Move init_bio_iter() and iter_bio_next() up in their source file so
the'll be defined before they're needed.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:15 -07:00
Alex Elder
fd154f3c75 libceph: don't mark footer complete before it is
This is a nit, but prepare_write_message() sets the FOOTER_COMPLETE
flag before the CRC for the data portion (recorded in the footer)
has been completely computed.  Hold off setting the complete flag
until we've decided it's ready to send.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:13 -07:00
Alex Elder
84ca8fc87f libceph: encapsulate advancing msg page
In write_partial_msg_pages(), once all the data from a page has been
sent we advance to the next one.  Put the code that takes care of
this into its own function.

While modifying write_partial_msg_pages(), make its local variable
"in_trail" be Boolean, and use the local variable "msg" (which is
just the connection's current out_msg pointer) consistently.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:12 -07:00
Alex Elder
739c905baa libceph: encapsulate out message data setup
Move the code that prepares to write the data portion of a message
into its own function.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05 21:14:10 -07:00
Sage Weil
d59315ca8c libceph: drop ceph_con_get/put helpers and nref member
These are no longer used.  Every ceph_connection instance is embedded in
another structure, and refcounts manipulated via the get/put ops.

Signed-off-by: Sage Weil <sage@inktank.com>
2012-06-22 08:13:45 -05:00
Sage Weil
36eb71aa57 libceph: use con get/put methods
The ceph_con_get/put() helpers manipulate the embedded con ref
count, which isn't used now that ceph_connections are embedded in
other structures.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
2012-06-22 07:30:27 -05:00