Pull nfsd updates from Bruce Fields:
"This includes a major rewrite of the NFSv4 state code, which has
always depended on a single mutex. As an example, open creates are no
longer serialized, fixing a performance regression on NFSv3->NFSv4
upgrades. Thanks to Jeff, Trond, and Benny, and to Christoph for
review.
Also some RDMA fixes from Chuck Lever and Steve Wise, and
miscellaneous fixes from Kinglong Mee and others"
* 'for-3.17' of git://linux-nfs.org/~bfields/linux: (167 commits)
svcrdma: remove rdma_create_qp() failure recovery logic
nfsd: add some comments to the nfsd4 object definitions
nfsd: remove the client_mutex and the nfs4_lock/unlock_state wrappers
nfsd: remove nfs4_lock_state: nfs4_state_shutdown_net
nfsd: remove nfs4_lock_state: nfs4_laundromat
nfsd: Remove nfs4_lock_state(): reclaim_complete()
nfsd: Remove nfs4_lock_state(): setclientid, setclientid_confirm, renew
nfsd: Remove nfs4_lock_state(): exchange_id, create/destroy_session()
nfsd: Remove nfs4_lock_state(): nfsd4_open and nfsd4_open_confirm
nfsd: Remove nfs4_lock_state(): nfsd4_delegreturn()
nfsd: Remove nfs4_lock_state(): nfsd4_open_downgrade + nfsd4_close
nfsd: Remove nfs4_lock_state(): nfsd4_lock/locku/lockt()
nfsd: Remove nfs4_lock_state(): nfsd4_release_lockowner
nfsd: Remove nfs4_lock_state(): nfsd4_test_stateid/nfsd4_free_stateid
nfsd: Remove nfs4_lock_state(): nfs4_preprocess_stateid_op()
nfsd: remove old fault injection infrastructure
nfsd: add more granular locking to *_delegations fault injectors
nfsd: add more granular locking to forget_openowners fault injector
nfsd: add more granular locking to forget_locks fault injector
nfsd: add a list_head arg to nfsd_foreach_client_lock
...
Add some comments that describe what each of these objects is, and how
they related to one another.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Also destroy_clientid and bind_conn_to_session.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Remove the old nfsd_for_n_state function and move nfsd_find_client
higher up into the file to get rid of forward declaration. Remove
the struct nfsd_fault_inject_op arguments from the operations as
they are no longer needed by any of them.
Finally, remove the old "standard" get and set routines, which
also eliminates the client_mutex from this code.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
...instead of relying on the client_mutex.
Also, fix up the printk output that is generated when the file is read.
It currently says that it's reporting the number of open files, but
it's actually reporting the number of openowners.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
In a later patch, we'll want to collect the locks onto a list for later
destruction. If "func" is defined and "collect" is defined, then we'll
add the lock stateid to the list.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
...which uses the client_lock for protection instead of client_mutex.
Also remove nfsd_forget_client as there are no more callers.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
...that relies on the client_lock instead of client_mutex.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Add a new "get" routine for forget_clients that relies on the
client_lock instead of the client_mutex.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Now that we've added more granular locking in other places, it's time
to address the fault injection code. This code is currently quite
reliant on the client_mutex for protection. Start to change this by
adding a new set of fault injection op vectors.
For now they all use the legacy ones. In later patches we'll add new
routines that can deal with more granular locking.
Also, move some of the printk routines into the callers to make the
results of the operations more uniform.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The clid counter is a global counter currently. Move it to be a per-net
property so that it can be properly protected by the nn->client_lock
instead of relying on the client_mutex.
The verifier generator is also potentially racy if there are two
simultaneous callers. Generate the verifier when we generate the clid
value, so it's also created under the client_lock. With this, there's
no need to keep two counters as they'd always be in sync anyway, so
just use the clientid_counter for both.
As Trond points out, what would be best is to eventually move this
code to use IDR instead of the hash tables. That would also help ensure
uniqueness, but that's probably best done as a separate project.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
It's possible that we'll have an in-progress call on some of the clients
while a rogue EXCHANGE_ID or DESTROY_CLIENTID call comes in. Be sure to
try and mark the client expired first, so that the refcount is
respected.
This will only be a problem once the client_mutex is removed.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If it fails, it means that the client is in use and so destroying it
would be bad. Currently, the client_mutex prevents this from happening
but once we remove it, we won't be able to do this.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
All the callers except for the fault injection code call it directly
afterward, and in the fault injection case it won't hurt to do so
anyway.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently, it's protected by the client_mutex. Move it so that the list
and the fields in the openowner are protected by the client_lock.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Ensure that the client lookup is done safely under the client_lock, so
we're not relying on the client_mutex.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
...instead of relying on the client_mutex.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
In particular, we want to ensure that the move_to_confirmed() is
protected by the nn->client_lock spin lock, so that we can use that when
looking up the clientid etc. instead of relying on the client_mutex.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
...instead of relying on the client_mutex.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
For efficiency reasons, and because we want to use spin locks instead
of relying on the client_mutex.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The struct nfs_client is supposed to be invisible and unreferenced
before it gets here.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If we leave the client on the confirmed/unconfirmed tables, and leave
the sessions visible on the sessionid_hashtbl, then someone might
find them before we've had a chance to destroy them.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When we remove the client_mutex protection, we will need to ensure
that it can't be found by other threads while we're destroying it.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
A memory allocation failure could cause nfsd_startup_generic to fail, in
which case nfsd_users wouldn't be incorrectly left elevated.
After nfsd restarts nfsd_startup_generic will then succeed without doing
anything--the first consequence is likely nfs4_start_net finding a bad
laundry_wq and crashing.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Fixes: 4539f14981 "nfsd: replace boolean nfsd_up flag by users counter"
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
...to better match other functions that deal with open/lock stateids.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When we remove the client_mutex, we'll have a potential race between
FREE_STATEID and CLOSE.
The root of the problem is that we are walking the st_locks list,
dropping the spinlock and then trying to release the persistent
reference to the lockstateid. In between, a FREE_STATEID call can come
along and take the lock, find the stateid and then try to put the
reference. That leads to a double put.
Fix this by not releasing the cl_lock in order to release each lock
stateid. Use put_generic_stateid_locked to unhash them and gather them
onto a list, and free_ol_stateid_reaplist to free any that end up on the
list.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Releasing an openowner is a bit inefficient as it can potentially thrash
the cl_lock if you have a lot of stateids attached to it. Once we remove
the client_mutex, it'll also potentially be dangerous to do this.
Add some functions to make it easier to defer the part of putting a
generic stateid reference that needs to be done outside the cl_lock while
doing the parts that must be done while holding it under a single lock.
First we unhash each open stateid. Then we call
put_generic_stateid_locked which will put the reference to an
nfs4_ol_stateid. If it turns out to be the last reference, it'll go
ahead and remove the stid from the IDR tree and put it onto the reaplist
using the st_locks list_head.
Then, after dropping the lock we'll call free_ol_stateid_reaplist to
walk the list of stateids that are fully unhashed and ready to be freed,
and free each of them. This function can sleep, so it must be done
outside any spinlocks.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Once we remove the client_mutex, it'll be possible for the sc_type of a
lock stateid to change after it's found and checked, but before we can
go to destroy it. If that happens, we can end up putting the persistent
reference to the stateid more than once, and unhash it more than once.
Fix this by unhashing the lock stateid prior to dropping the cl_lock but
after finding it.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Reduce the cl_lock trashing in destroy_lockowner. Unhash all of the
lockstateids on the lockowner's list. Put the reference under the lock
and see if it was the last one. If so, then add it to a private list
to be destroyed after we drop the lock.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Once we remove the client_mutex, we'll need to properly protect
the stateowner reference counts using the cl_lock.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Do more within the main loop, and simplify the function a bit. Also,
there's no need to take a stateowner reference unless we're going to call
release_lockowner.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Preparation for removing the client_mutex.
Convert the open owner hash table into a per-client table and protect it
using the nfs4_client->cl_lock spin lock.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Once we remove client mutex protection, we'll need to ensure that
stateowner lookup and creation are atomic between concurrent compounds.
Ensure that alloc_init_lock_stateowner checks the hashtable under the
client_lock before adding a new element.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
