Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-qc0-f174.google.com ([209.85.216.174]:34778 "EHLO mail-qc0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757787AbaFSOu6 (ORCPT ); Thu, 19 Jun 2014 10:50:58 -0400 Received: by mail-qc0-f174.google.com with SMTP id x13so2274590qcv.33 for ; Thu, 19 Jun 2014 07:50:58 -0700 (PDT) From: Jeff Layton To: bfields@fieldses.org Cc: linux-nfs@vger.kernel.org Subject: [PATCH v1 000/104] nfsd: eliminate the client_mutex Date: Thu, 19 Jun 2014 10:49:06 -0400 Message-Id: <1403189450-18729-1-git-send-email-jlayton@primarydata.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: Here it is. The long awaited removal of the client_mutex from knfsd. As many of us are aware, one of the major bottlenecks in NFSv4 serving is the fact that all compounds are processed while holding a single, global mutex. This has an obvious detrimental effect on scalability. I've heard anecdotal reports of 10x slowdowns with v4 serving vs. v3 on the same machine, primarily due to it. This patchset eliminates that mutex and (hopefully!) the bottleneck that it imposes. The basic idea is to add refcounting to most of the objects that compounds deal with to ensure that they are pinned while in use. Spinlocks are used to protect things like the hashtables and trees that track the objects. Benny started this set quite some time ago, and Trond took up the torch early this spring. He then handed it to me to clean up the remaining bits about a month ago. I'd like to see this considered for v3.17. Obviously, getting it into linux-next ASAP would be a good thing once it passes review. Some other highlights/notes: - use of lockdep has been greatly increased. I found it was the only way to ensure that I didn't create lock inversion problems and such. - clients are now only looked up once per compund and are cached in the cstate. This keeps us from having to keep searching for the same client for each compound op. - openowners and lockowners are now handled more sanely. References to them are only held by the stateids that are associated with them, and they are destroyed when the last reference to them is put. Also, lockowners can now have more than one stateid (in accordance with the spec) - the fault injection code has been overhauled. It should look the same to users, but it needed major work to deal with the new locking. It's probably possible to consolidate some of that code as well -- it more cut-and-pastey than I'd like. - I've added a file to document how all of the moving parts fit together. It probably can use more fleshing out, but it's a start. - the lease handling is now a bit more complex than I'd like. Lease removal in particular is currently called under a spinlock, which I think we'll need to eventually clean up. For now, this is ok since the first thing that vfs_setlease does is lock the i_lock, but I think we'll eventually need to do an i_lock pushdown in the lease handling code, and ensure that vfs_setlease isn't called under a spinlock. As always, comments and review are welcome. Benny Halevy (1): nfsd4: use cl_lock to synchronize all stateid idr calls Jeff Layton (40): NFSd: Ensure that nfs4_file_get_access enforces share access modes locks: add file_has_lease NFSd: Protect the nfs4_file delegation fields using the fi_lock NFSd: Allow lockowners to hold several stateids NFSd: Ensure atomicity of stateid destruction and idr tree removal NFSd: Cleanup the freeing of stateids nfsd: do filp_close in sc_free callback for lock stateids NFSd: Add locking to protect the state owner lists nfsd: clean up races in lock stateid searching and creation nfsd: clean up lockowner refcounting when finding them nfsd: add an operation for unhashing a stateowner nfsd: clean up nfs4_release_lockowner nfsd: clean up refcounting for lockowners nfsd: declare v4.1+ openowners confirmed on creation nfsd: make openstateids hold references to their openowners nfsd: don't allow CLOSE to proceed until refcount on stateid drops lockdep: add lockdep_assert_not_held nfsd: add locking to stateowner release nfsd: optimize destroy_lockowner cl_lock thrashing nfsd: reduce cl_lock trashing in release_openowner NFSd: Protect session creation and client confirm using client_lock nfsd: protect the close_lru list and oo_last_closed_stid with client_lock nfsd: ensure that clp->cl_revoked list is protected by clp->cl_lock nfsd: move unhash_client_locked call into mark_client_expired_locked nfsd: fix misleading comment nfsd: don't destroy client if mark_client_expired_locked fails nfsd: don't destroy clients that are busy nfsd: abstract out the get and set routines into the fault injection ops nfsd: add a forget_clients "get" routine with proper locking nfsd: add a forget_client set_clnt routine nfsd: add nfsd_inject_forget_clients nfsd: add a list_head arg to nfsd_foreach_client_lock nfsd: add more granular locking to forget_locks fault injector nfsd: add more granular locking to forget_openowners fault injector nfsd: add more granular locking to *_delegations fault injectors nfsd: remove old fault injection infrastructure nfsd: remove nfs4_lock_state: nfs4_laundromat nfsd: remove nfs4_lock_state: nfs4_state_shutdown_net nfsd: remove the client_mutex and the nfs4_lock/unlock_state wrappers nfsd: add file documenting new state object model Trond Myklebust (63): nfsd: Protect addition to the file_hashtbl NFSd: Avoid taking state_lock while holding inode lock in nfsd_break_one_deleg NFSd: nfs4_preprocess_seqid_op should only set *stpp on success NFSd: Add fine grained protection for the nfs4_file->fi_stateids list NFSd: Add a mutex to protect the NFSv4.0 open owner replay cache NFSd: Add locking to the nfs4_file->fi_fds[] array NFSd: Lock owners are not per open stateid NFSd: Clean up helper __release_lock_stateid NFSd: NFSv4 lock-owners are not associated to a specific file NFSd: Cleanup nfs4svc_encode_compoundres NFSd: Don't get a session reference without a client reference NFSd: Allow struct nfsd4_compound_state to cache the nfs4_client NFSd: Move the delegation reference counter into the struct nfs4_stid NFSd: Simplify stateid management NFSd: Fix delegation revocation NFSd: Add reference counting to the lock and open stateids NFSd: clean up nfsd4_close_open_stateid NFSd: Add a struct nfs4_file field to struct nfs4_stid NFSd: Replace nfs4_ol_stateid->st_file with the st_stid.sc_file NFSd: Ensure stateids remain unique until they are freed NFSd: Convert delegation counter to an atomic_long_t type NFSd: Slight cleanup of find_stateid() NFSd: Add reference counting to find_stateid NFSd: Add reference counting to lock stateids NFSd: nfsd4_locku() must reference the lock stateid NFSd: Ensure that nfs4_open_delegation() references the delegation stateid NFSd: nfsd4_process_open2() must reference the delegation stateid NFSd: nfsd4_process_open2() must reference the open stateid NFSd: Prepare nfsd4_close() for open stateid referencing NFSd: nfsd4_open_confirm() must reference the open stateid NFSd: Add reference counting to nfs4_preprocess_confirmed_seqid_op NFSd: Migrate the stateid reference into nfs4_preprocess_seqid_op NFSd: Migrate the stateid reference into nfs4_lookup_stateid() NFSd: Migrate the stateid reference into nfs4_find_stateid_by_type() NFSd: Add reference counting to state owners NFSd: Keep a reference to the open stateid for the NFSv4.0 replay cache NFSd: Make lock stateid take a reference to the lockowner NFSd: Protect adding/removing open state owners using client_lock NFSd: Protect adding/removing lock owners using client_lock NFSd: Cleanup - Let nfsd4_lookup_stateid() take a cstate argument NFSd: Cache the client that was looked up in lookup_clientid() NFSd: Convert nfsd4_process_open1() to work with lookup_clientid() NFSd: Always use lookup_clientid() in nfsd4_process_open1 NFSd: Move the open owner hash table into struct nfs4_client NFSd: Convert nfs4_check_open_reclaim() to work with lookup_clientid() NFSd: Ensure struct nfs4_client is unhashed before we try to destroy it NFSd: Ensure that the laundromat unhashes the client before releasing locks NFSd: Don't require client_lock in free_client NFSd: Move create_client() call outside the lock NFSd: Protect unconfirmed client creation using client_lock NFSd: Protect nfsd4_destroy_clientid using client_lock NFSd: Ensure lookup_clientid() takes client_lock NFSd: Add assertions to document the nfs4_client/session locking NFSd: Remove nfs4_lock_state(): nfs4_preprocess_stateid_op() NFSd: Remove nfs4_lock_state(): nfsd4_test_stateid/nfsd4_free_stateid NFSd: Remove nfs4_lock_state(): nfsd4_release_lockowner NFSd: Remove nfs4_lock_state(): nfsd4_lock/locku/lockt() NFSd: Remove nfs4_lock_state(): nfsd4_open_downgrade + nfsd4_close NFSd: Remove nfs4_lock_state(): nfsd4_delegreturn() NFSd: Remove nfs4_lock_state(): nfsd4_open and nfsd4_open_confirm NFSd: Remove nfs4_lock_state(): exchange_id, create/destroy_session() NFSd: Remove nfs4_lock_state(): setclientid, setclientid_confirm, renew NFSd: Remove nfs4_lock_state(): reclaim_complete() .../filesystems/nfs/nfsd4-state-objects.txt | 110 + fs/locks.c | 26 + fs/nfsd/fault_inject.c | 129 +- fs/nfsd/netns.h | 5 - fs/nfsd/nfs4callback.c | 18 +- fs/nfsd/nfs4proc.c | 16 +- fs/nfsd/nfs4state.c | 2569 ++++++++++++++------ fs/nfsd/nfs4xdr.c | 17 +- fs/nfsd/state.h | 86 +- fs/nfsd/xdr4.h | 8 +- include/linux/fs.h | 6 + include/linux/lockdep.h | 6 + 12 files changed, 2052 insertions(+), 944 deletions(-) create mode 100644 Documentation/filesystems/nfs/nfsd4-state-objects.txt -- 1.9.3