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2014-08-09Merge branch 'for-3.17' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
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 ...
2014-08-05nfsd: add some comments to the nfsd4 object definitionsJeff Layton
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>
2014-08-05nfsd: remove the client_mutex and the nfs4_lock/unlock_state wrappersJeff Layton
Signed-off-by: Jeff Layton <jlayton@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05nfsd: remove nfs4_lock_state: nfs4_state_shutdown_netJeff Layton
Signed-off-by: Jeff Layton <jlayton@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05nfsd: remove nfs4_lock_state: nfs4_laundromatJeff Layton
Signed-off-by: Jeff Layton <jlayton@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05nfsd: Remove nfs4_lock_state(): reclaim_complete()Trond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05nfsd: Remove nfs4_lock_state(): setclientid, setclientid_confirm, renewTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05nfsd: Remove nfs4_lock_state(): exchange_id, create/destroy_session()Trond Myklebust
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>
2014-08-05nfsd: Remove nfs4_lock_state(): nfsd4_open and nfsd4_open_confirmTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05nfsd: Remove nfs4_lock_state(): nfsd4_delegreturn()Trond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05nfsd: Remove nfs4_lock_state(): nfsd4_open_downgrade + nfsd4_closeTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05nfsd: Remove nfs4_lock_state(): nfsd4_lock/locku/lockt()Trond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05nfsd: Remove nfs4_lock_state(): nfsd4_release_lockownerTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05nfsd: Remove nfs4_lock_state(): nfsd4_test_stateid/nfsd4_free_stateidTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05nfsd: Remove nfs4_lock_state(): nfs4_preprocess_stateid_op()Trond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05nfsd: remove old fault injection infrastructureJeff Layton
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>
2014-08-05nfsd: add more granular locking to *_delegations fault injectorsJeff Layton
...instead of relying on the client_mutex. Signed-off-by: Jeff Layton <jlayton@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05nfsd: add more granular locking to forget_openowners fault injectorJeff Layton
...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>
2014-08-05nfsd: add more granular locking to forget_locks fault injectorJeff Layton
...instead of relying on the client_mutex. Signed-off-by: Jeff Layton <jlayton@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05nfsd: add a list_head arg to nfsd_foreach_client_lockJeff Layton
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>
2014-08-05nfsd: add nfsd_inject_forget_clientsJeff Layton
...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>
2014-08-05nfsd: add a forget_client set_clnt routineJeff Layton
...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>
2014-08-05nfsd: add a forget_clients "get" routine with proper lockingJeff Layton
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>
2014-08-05nfsd: abstract out the get and set routines into the fault injection opsJeff Layton
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>
2014-08-05nfsd: protect clid and verifier generation with client_lockJeff Layton
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>
2014-08-05nfsd: don't destroy clients that are busyJeff Layton
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>
2014-08-05NFSD: Put the reference of nfs4_file when freeing stidKinglong Mee
After testing nfs4 lock, I restart the nfsd service, got messages as, [ 5677.403419] nfsd: last server has exited, flushing export cache [ 5677.463728] ============================================================================= [ 5677.463942] BUG nfsd4_files (Tainted: G B OE): Objects remaining in nfsd4_files on kmem_cache_close() [ 5677.464055] ----------------------------------------------------------------------------- [ 5677.464203] INFO: Slab 0xffffea0000233400 objects=28 used=1 fp=0xffff880008cd3d98 flags=0x3ffc0000004080 [ 5677.464318] CPU: 0 PID: 3772 Comm: rmmod Tainted: G B OE 3.16.0-rc2+ #29 [ 5677.464420] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/31/2013 [ 5677.464538] 0000000000000000 0000000036af2c9f ffff88000ce97d68 ffffffff816eacfa [ 5677.464643] ffffea0000233400 ffff88000ce97e40 ffffffff811cda44 ffffffff00000020 [ 5677.464774] ffff88000ce97e50 ffff88000ce97e00 656a624f00000008 616d657220737463 [ 5677.464875] Call Trace: [ 5677.464925] [<ffffffff816eacfa>] dump_stack+0x45/0x56 [ 5677.464983] [<ffffffff811cda44>] slab_err+0xb4/0xe0 [ 5677.465040] [<ffffffff811d0457>] ? __kmalloc+0x117/0x290 [ 5677.465099] [<ffffffff81100eec>] ? on_each_cpu_cond+0xac/0xf0 [ 5677.465158] [<ffffffff811d1bc0>] ? kmem_cache_close+0x110/0x2e0 [ 5677.465218] [<ffffffff811d1be0>] kmem_cache_close+0x130/0x2e0 [ 5677.465279] [<ffffffff8135a0c1>] ? kobject_cleanup+0x91/0x1b0 [ 5677.465338] [<ffffffff811d22be>] __kmem_cache_shutdown+0xe/0x10 [ 5677.465399] [<ffffffff8119bd28>] kmem_cache_destroy+0x48/0x100 [ 5677.465466] [<ffffffffa05ef78d>] nfsd4_free_slabs+0x2d/0x50 [nfsd] [ 5677.465530] [<ffffffffa05fa987>] exit_nfsd+0x34/0x6ad [nfsd] [ 5677.465589] [<ffffffff81104ac2>] SyS_delete_module+0x162/0x200 [ 5677.465649] [<ffffffff81013b69>] ? do_notify_resume+0x59/0x90 [ 5677.465759] [<ffffffff816f2369>] system_call_fastpath+0x16/0x1b [ 5677.465822] INFO: Object 0xffff880008cd0000 @offset=0 [ 5677.465882] INFO: Allocated in nfsd4_process_open1+0x61/0x350 [nfsd] age=7599 cpu=0 pid=3253 [ 5677.466115] __slab_alloc+0x3b0/0x4b1 [ 5677.466166] kmem_cache_alloc+0x1e4/0x240 [ 5677.466220] nfsd4_process_open1+0x61/0x350 [nfsd] [ 5677.466276] nfsd4_open+0xee/0x860 [nfsd] [ 5677.466329] nfsd4_proc_compound+0x4d7/0x7f0 [nfsd] [ 5677.466384] nfsd_dispatch+0xbb/0x200 [nfsd] [ 5677.466447] svc_process_common+0x453/0x6f0 [sunrpc] [ 5677.466506] svc_process+0x103/0x170 [sunrpc] [ 5677.466559] nfsd+0x117/0x190 [nfsd] [ 5677.466609] kthread+0xd8/0xf0 [ 5677.466656] ret_from_fork+0x7c/0xb0 [ 5677.466775] kmem_cache_destroy nfsd4_files: Slab cache still has objects [ 5677.466839] CPU: 0 PID: 3772 Comm: rmmod Tainted: G B OE 3.16.0-rc2+ #29 [ 5677.466937] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/31/2013 [ 5677.467049] 0000000000000000 0000000036af2c9f ffff88000ce97eb0 ffffffff816eacfa [ 5677.467150] ffff880020bb2d00 ffff88000ce97ed0 ffffffff8119bdd9 0000000000000000 [ 5677.467250] ffffffffa06065c0 ffff88000ce97ee0 ffffffffa05ef78d ffff88000ce97ef0 [ 5677.467351] Call Trace: [ 5677.467397] [<ffffffff816eacfa>] dump_stack+0x45/0x56 [ 5677.467454] [<ffffffff8119bdd9>] kmem_cache_destroy+0xf9/0x100 [ 5677.467516] [<ffffffffa05ef78d>] nfsd4_free_slabs+0x2d/0x50 [nfsd] [ 5677.467579] [<ffffffffa05fa987>] exit_nfsd+0x34/0x6ad [nfsd] [ 5677.467639] [<ffffffff81104ac2>] SyS_delete_module+0x162/0x200 [ 5677.467765] [<ffffffff81013b69>] ? do_notify_resume+0x59/0x90 [ 5677.467826] [<ffffffff816f2369>] system_call_fastpath+0x16/0x1b Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Reviewed-by: Jeff Layton <jlayton@primarydata.com> Fixes: 11b9164adad7 "nfsd: Add a struct nfs4_file field to struct nfs4_stid" Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-01nfsd: don't destroy client if mark_client_expired_locked failsJeff Layton
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>
2014-08-01nfsd: move unhash_client_locked call into mark_client_expired_lockedJeff Layton
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>
2014-08-01nfsd: protect the close_lru list and oo_last_closed_stid with client_lockJeff Layton
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>
2014-08-01nfsd: Add lockdep assertions to document the nfs4_client/session lockingTrond Myklebust
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>
2014-08-01nfsd: Ensure lookup_clientid() takes client_lockTrond Myklebust
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>
2014-08-01nfsd: Protect nfsd4_destroy_clientid using client_lockTrond Myklebust
...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>
2014-08-01nfsd: Protect session creation and client confirm using client_lockJeff Layton
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>
2014-08-01nfsd: Protect unconfirmed client creation using client_lockTrond Myklebust
...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>
2014-08-01nfsd: Move create_client() call outside the lockTrond Myklebust
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>
2014-08-01nfsd: Don't require client_lock in free_clientTrond Myklebust
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>
2014-08-01nfsd: Ensure that the laundromat unhashes the client before releasing locksTrond Myklebust
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>
2014-08-01nfsd: Ensure struct nfs4_client is unhashed before we try to destroy itTrond Myklebust
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>
2014-08-01nfsd4: fix out of date commentJ. Bruce Fields
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-01NFSD: Decrease nfsd_users in nfsd_startup_generic failKinglong Mee
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: 4539f14981ce "nfsd: replace boolean nfsd_up flag by users counter" Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-07-31nfsd: rename unhash_generic_stateid to unhash_ol_stateidJeff Layton
...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>
2014-07-31nfsd: don't thrash the cl_lock while freeing an open stateidJeff Layton
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>
2014-07-31nfsd: reduce cl_lock thrashing in release_openownerJeff Layton
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>
2014-07-31nfsd: close potential race in nfsd4_free_stateidJeff Layton
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>
2014-07-31nfsd: optimize destroy_lockowner cl_lock thrashingJeff Layton
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>
2014-07-31nfsd: add locking to stateowner releaseJeff Layton
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>
2014-07-31nfsd: clean up and reorganize release_lockownerJeff Layton
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>
2014-07-31nfsd: Move the open owner hash table into struct nfs4_clientTrond Myklebust
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>
2014-07-31nfsd: Protect adding/removing lock owners using client_lockTrond Myklebust
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>