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* dlm: use rcu to avoid an extra rsb struct lookupAlexander Aring2024-06-101-15/+87
| | | | | | | | | | | | Use rcu to free rsb structs, and hold the rcu read lock while looking up rsb structs. This allows us to avoid an extra hash table lookup for an rsb. A new rsb flag HASHED is added which is set while the rsb is in the hash table. This flag is checked in place of repeating the hash table lookup. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: fix add_scan and del_scan usageDavid Teigland2024-06-101-22/+35
| | | | | | | | | Remove a few calls to add_scan() and del_scan() in cases where the rsb is a dir record, so the rsb should never be placed on the scan list at all. Add WARN_ON to catch cases where this is done. Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: change list and timer namesDavid Teigland2024-06-101-168/+140
| | | | | | | | | | | | | | | | | | | | The old terminology of "toss" and "keep" is no longer an accurate description of the rsb states and lists, so change the names to "inactive" and "active". The old names had also been copied into the scanning code, which is changed back to use the "scan" name. - "active" rsb structs have lkb's attached, and are ref counted. - "inactive" rsb structs have no lkb's attached, are not ref counted. - "scan" list is for rsb's that can be freed after a timeout period. - "slow" lists are for infrequent iterations through active or inactive rsb structs. - inactive rsb structs that are directory records will not be put on the scan list, since they are not freed based on timeouts. - inactive rsb structs that are not directory records will be put on the scan list to be freed, since they are not longer needed. Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: move lkb idr to xarray datastructureAlexander Aring2024-05-311-14/+16
| | | | | | | | According to kernel doc idr is deprecated and xarrays should be used nowadays. This patch is moving the lkb idr implementation to xarrays. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: drop own rsb pre allocation mechanismAlexander Aring2024-05-311-80/+12
| | | | | | | | | This patch drops the own written rsb pre allocation mechanism as this is already done by using kmem caches, we don't need another layer on top of that to running some pre allocation scheme. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: don't kref_init rsbs created for toss listAlexander Aring2024-05-311-1/+0
| | | | | | | | | | This patch removes a kref_init() that isn't necessary because the rsb is created for toss list. Under toss list the rsb should not have any reference counting logic. If in theory the rsb gets to into keep list then a kref_init() for res_ref will be initiated. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: fix sleep in atomic contextAlexander Aring2024-04-171-6/+6
| | | | | | | | | | | | | | | | | | This patch changes the orphans mutex to a spinlock since commit c288745f1d4a ("dlm: avoid blocking receive at the end of recovery") is using a rwlock_t to lock the DLM message receive path and do_purge() can be called while this lock is held that forbids to sleep. We need to use spin_lock_bh() because also a user context that calls dlm_user_purge() can call do_purge() and since commit 92d59adfaf71 ("dlm: do message processing in softirq context") the DLM message receive path is done under softirq context. Fixes: c288745f1d4a ("dlm: avoid blocking receive at the end of recovery") Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Closes: https://lore.kernel.org/gfs2/9ad928eb-2ece-4ad9-a79c-d2bce228e4bc@moroto.mountain/ Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: use rwlock for lkbidrAlexander Aring2024-04-161-37/+7
| | | | | | | | Convert the lock for lkbidr to an rwlock. Most idr lookups will use the read lock. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: use rwlock for rsb hash tableAlexander Aring2024-04-161-75/+194
| | | | | | | | | | The conversion to rhashtable introduced a hash table lock per lockspace, in place of per bucket locks. To make this more scalable, switch to using a rwlock for hash table access. The common case fast path uses it as a read lock. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: drop dlm_scand kthread and use timersAlexander Aring2024-04-161-142/+240
| | | | | | | | | | | | | | | | | | | Currently the scand kthread acts like a garbage collection for expired rsbs on toss list, to clean them up after a certain timeout. It triggers every couple of seconds and iterates over the toss list while holding ls_rsbtbl_lock for the whole hash bucket iteration. To reduce the amount of time holding ls_rsbtbl_lock, we now handle the disposal of expired rsbs using a per-lockspace timer that expires for the earliest tossed rsb on the lockspace toss queue. This toss queue is ordered according to the rsb res_toss_time with the earliest tossed rsb as the first entry. The toss timer will only trylock() necessary locks, since it is low priority garbage collection, and will rearm the timer if trylock() fails. If the timer function does not find any expired rsb's, it rearms the timer with the next earliest expired rsb. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: do not use ref counts for rsb in the toss stateAlexander Aring2024-04-161-31/+30
| | | | | | | | | | | | | In the past we had problems when an rsb had a reference counter greater than one while in the toss state. An rsb in the toss state is not actively used for locking, and should not have any other references apart from the single ref keeping it on the rsb hash. Shift to freeing rsb's directly rather than using kref_put to free them, since the ref counting is not meant to be used in this state. Add warnings if ref counting is seen while an rsb is in the toss state. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: switch to use rhashtable for rsbsAlexander Aring2024-04-161-118/+54
| | | | | | | | Replace our own hash table with the more advanced rhashtable for keeping rsb structs. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: add rsb lists for iterationAlexander Aring2024-04-161-26/+21
| | | | | | | | | | To prepare for using rhashtable, add two rsb lists for iterating through rsb's in two uncommon cases where this is necesssary: - when dumping rsb state from debugfs, now using seq_list. - when looking at all rsb's during recovery. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: merge toss and keep hash table lists into one listAlexander Aring2024-04-161-48/+55
| | | | | | | | | | | There are several places where lock processing can perform two hash table lookups, first in the "keep" list, and if not found, in the "toss" list. This patch introduces a new rsb state flag "RSB_TOSS" to represent the difference between the state of being on keep vs toss list, so that the two lists can be combined. This avoids cases of two lookups. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: change to single hashtable lockAlexander Aring2024-04-161-39/+38
| | | | | | | | Prepare to replace our own hash table with rhashtable by replacing the per-bucket locks in our own hash table with a single lock. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: use spin_lock_bh for message processingAlexander Aring2024-04-091-88/+118
| | | | | | | | | | Use spin_lock_bh for all spinlocks involved in message processing, in preparation for softirq message processing. DLM lock requests from user space involve dlm processing in user context, in addition to the standard kernel context, necessitating bh variants. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: remove schedule in receive pathAlexander Aring2024-04-091-1/+0
| | | | | | | | Remove an explicit schedule() call in the message processing path, in preparation for softirq message processing. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: convert ls_recv_active from rw_semaphore to rwlockAlexander Aring2024-04-091-2/+2
| | | | | | | | Convert ls_recv_active rw_semaphore to an rwlock to avoid sleeping, in preparation for softirq message processing. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: avoid blocking receive at the end of recoveryAlexander Aring2024-04-091-2/+14
| | | | | | | | | | | | | | | The end of the recovery process transitioned to normal message processing by temporarily blocking the receiving context, processing saved messages, then unblocking the receiving context. To avoid blocking the receiving context, the old wait_queue and mutex are replaced by a new rwlock and the new RECV_MSG_BLOCKED flag. Received messages are added to the list of saved messages, protected by the rwlock, until the flag is cleared, which happens when all saved messages have been processed. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: convert res_lock to spinlockAlexander Aring2024-04-091-1/+1
| | | | | | | | Convert the rsb struct res_lock from a mutex to a spinlock in preparation for processing messages in softirq context. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: convert ls_waiters_mutex to spinlockAlexander Aring2024-04-091-10/+10
| | | | | | | | Convert the waiters mutex to a spinlock in prepration for processing messages in softirq context. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: drop mutex use in waiters recoveryAlexander Aring2024-04-091-8/+9
| | | | | | | | | | | | | | The waiters_mutex no longer needs to be used in the waiters recovery functions dlm_recover_waiters_pre() and dlm_recover_waiters_pre(). During recovery, ordinary locking operations are paused, and the recovery thread is the only context accessing the waiters list, so the lock is not needed. Access to the waiters list from debugfs functions is avoided by taking the top level recovery lock in the debugfs dump function. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: move rsb root_list to ls_recover() stackAlexander Aring2024-04-091-4/+2
| | | | | | | | Move the rsb root_list from the lockspace to a stack variable since it is now only used by the ls_recover() function. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: use a new list for recovery of master rsb namesAlexander Aring2024-04-091-0/+2
| | | | | | | | | | Add a new "masters_list" for master rsb structs, with a new rwlock. The new list is created and used during the recovery process to send the master rsb names to new nodes. With this change, the current "root_list" can be used without locking. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: switch to GFP_ATOMIC in dlm allocationsAlexander Aring2024-04-091-2/+0
| | | | | | | | | Replace GFP_NOFS with GFP_ATOMIC. Also stop using idr_preload which uses a non-bh spin_lock. This is further preparation for softirq message processing. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: remove allocation parameter in msg allocationAlexander Aring2024-04-091-19/+12
| | | | | | | | | Remove the context parameter for message allocations and always use GFP_ATOMIC. This prepares for softirq message processing. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: remove callback reference countingAlexander Aring2024-04-011-3/+5
| | | | | | | | | | | Get rid of the unnecessary refcounting on callback structs. Copy interesting callback info into the lkb struct rather than maintaining pointers to callback structs from the lkb. This goes back to the way things were done prior to commit 61bed0baa4db ("fs: dlm: use a non-static queue for callbacks"). Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: fix race between final callback and removeAlexander Aring2024-04-011-12/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes the following issue: node 1 is dir node 2 is master node 3 is other 1->2: unlock 2: put final lkb, rsb moved to toss 2->1: unlock_reply 1: queue lkb callback with EUNLOCK 2->1: remove 1: receive_remove ignored (rsb on keep because of queued lkb callback) 1: complete lkb callback, put_lkb, move rsb to toss 3->1: lookup 1->3: lookup_reply master=2 3->2: request 2->3: request_reply EBADR In summary: An unexpected lkb reference causes the rsb to remain on the wrong list. The rsb being on the wrong list causes receive_remove to be ignored. An ignored receive_remove causes inconsistent dir and master state. This sequence requires an unusually long delay in delivering the unlock callback, because the remove message from 2->1 usually happens after some seconds. So, it's not known exactly how frequently this sequence occurs in pratice. It's possible that the same end result could also have another unknown cause. The solution for this issue is to further separate callback state from the lkb, so that an lkb reference (and from that, an rsb ref) are not held while a callback remains queued. Then, within the unlock_reply, the lkb will be freed and the rsb moved to the toss list. So, the receive_remove will not be ignored. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: add comments about forced waiters resetDavid Teigland2024-03-151-20/+58
| | | | | | | | | | When a lock is waiting for a reply for a remote operation, and recovery interrupts this "waiters" state, the remote operation is voided by the recovery, and no reply will be processed. The lkb waiters state for the remote operation is forcibly reset/cleared, so that the lock operation can be restarted after recovery. Improve the comments describing this. Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: revert atomic_t lkb_wait_countDavid Teigland2024-03-151-14/+18
| | | | | | | | | | | Revert "fs: dlm: handle lkb wait count as atomic_t" This reverts commit 75a7d60134ce84209f2c61ec4619ee543aa8f466. This counter does not need to be atomic. As the comment in the reverted commit mentions, the counter is protected by the rsb lock. Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: constify receive bufferAlexander Aring2023-08-101-51/+58
| | | | | | | | | The dlm receive buffer should be never manipulated as DLM is the last instance of parsing layer. This patch constify the whole receive buffer so we are sure it never gets manipulated when it's being parsed. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: drop rxbuf manipulation in dlm_recover_master_copyAlexander Aring2023-08-101-3/+7
| | | | | | | | | | | | | Currently dlm_recover_master_copy() manipulates the receive buffer of an rcom lock message and modifies it on the fly so a later memcpy() to a new rcom message with the same message has those new values. This patch avoids manipulating the received rcom message by store the values for the new rcom message in paremter assigned with call by reference. Later when dlm_send_rcom_lock() constructs a new message and memcpy() the receive buffer those values will be set on the new constructed message. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: get recovery sequence number as parameterAlexander Aring2023-08-101-2/+3
| | | | | | | | | | | | | This patch removes a read of the ls->ls_recover_seq uint64_t number in _create_rcom(). If the ls->ls_recover_seq is readed the ls_recover_lock need to held. However this number was always readed before when any rcom message is received and it's not necessary to read it again from a per lockspace variable to use it for the replying message. This patch will pass the sequence number as parameter so another read of ls->ls_recover_seq and holding the ls->ls_recover_lock is not required. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: handle lkb wait count as atomic_tAlexander Aring2023-06-141-18/+14
| | | | | | | | | | Currently the lkb_wait_count is locked by the rsb lock and it should be fine to handle lkb_wait_count as non atomic_t value. However for the overall process of reducing locking this patch converts it to an atomic_t value. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: warn about messages from left nodesAlexander Aring2023-06-141-2/+2
| | | | | | | | | | | | | | | | | This patch warns about messages which are received from nodes who already left the lockspace resource signaled by the cluster manager. Before commit 489d8e559c65 ("fs: dlm: add reliable connection if reconnect") there was a synchronization issue with the socket lifetime and the cluster event of leaving a lockspace and other nodes did not stop of sending messages because the cluster manager has a pending message to leave the lockspace. The reliable session layer for dlm use sequence numbers to ensure dlm message were never being dropped. If this is not corrected synchronized we have a problem, this patch will use the filter case and turn it into a WARN_ON_ONCE() so we seeing such issue on the kernel log because it should never happen now. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: stop unnecessarily filling zero ms_extra bytesAlexander Aring2023-04-211-1/+1
| | | | | | | | | | | | | | | | | | | Commit 7175e131ebba ("fs: dlm: fix invalid derefence of sb_lvbptr") fixes an issue when the lkb->lkb_lvbptr set to an dangled pointer and an followed memcpy() would fail. It was fixed by an additional check of DLM_LKF_VALBLK flag. The mentioned commit forgot to add an additional check if DLM_LKF_VALBLK is set for the additional amount of LVB data allocated in a dlm message. This patch is changing the message allocation to check additionally if DLM_LKF_VALBLK is set otherwise a dangled lkb->lkb_lvbptr pointer would allocated zero LVB message data which not gets filled with actual data. This patch is however only a cleanup to reduce the amount of zero bytes transmitted over network as receive_lvb() will only evaluates message LVB data if DLM_LKF_VALBLK is set. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: switch lkb_sbflags to atomic opsAlexander Aring2023-03-061-11/+11
| | | | | | | | | This patch moves lkb_sbflags handling to atomic bits ops. This should prepare for a possible manipulating of lkb_sbflags flags at the same time by concurrent execution. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: rsb hash table flag value to atomic opsAlexander Aring2023-03-061-4/+4
| | | | | | | | | | | This patch moves the rsb hash table handling to atomic flag operations. The flag operations for DLM_RTF_SHRINK are protected by ls->ls_rsbtbl[b].lock. However we switch to atomic ops if new possible flags will be used in a different way and don't assume such lock dependencies. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: move internal flags to atomic opsAlexander Aring2023-03-061-63/+64
| | | | | | | | | | | | | This patch will move the lkb_flags value to the recently introduced lkb_iflags value. For lkb_iflags we use atomic bit operations because some flags like DLM_IFL_CB_PENDING are used while non rsb lock is held to avoid issues with other flag manipulations which might run at the same time we switch to atomic bit operations. Snapshot the bit values to an uint32_t value is only used for debugging/logging use cases and don't need to be 100% correct. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: change dflags to use atomic bitsAlexander Aring2023-03-061-13/+13
| | | | | | | | | | | | | | | | | Currently manipulating lkb_dflags assumes to held the rsb lock assigned to the lkb. This is held by dlm message processing after certain time to lookup the right rsb from the received lkb message id. For user space locks flags, which is currently the only use case for lkb_dflags, flags are also being set during dlm character device handling without holding the rsb lock. To minimize the risk that bit operations are getting corrupted we switch to atomic bit operations. This patch will also introduce helpers to snapshot atomic bit values in an non atomic way. There might be still issues with the flag handling e.g. running in case of manipulating bit ops and snapshot them at the same time, but this patch minimize them and will start to use atomic bit operations. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: store lkb distributed flags into own valueAlexander Aring2023-03-061-15/+13
| | | | | | | | | | | This patch stores lkb distributed flags value in an separate value instead of sharing internal and distributed flags in lkb->lkb_flags value. This has the advantage to not mask/write back flag values in receive_flags() functionality. The dlm debug_fs does not provide the distributed flags anymore, those can be added in future. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: remove DLM_IFL_LOCAL_MS flagAlexander Aring2023-03-061-32/+33
| | | | | | | | | | | The DLM_IFL_LOCAL_MS flag is an internal non shared flag but used in m_flags of dlm messages. It is not shared because it is only used for local messaging. Instead using DLM_IFL_LOCAL_MS in dlm messages we pass a parameter around to signal local messaging or not. This patch is adding the local parameter to signal local messaging. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: rename stub to local message flagAlexander Aring2023-03-061-53/+53
| | | | | | | | | | This patch renames DLM_IFL_STUB_MS to DLM_IFL_LOCAL_MS flag. The DLM_IFL_STUB_MS flag is somewhat misnamed, it means the dlm message is used for local message transfer only. It is used by recovery to resolve lock states if a node got fenced. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: remove deprecated code partsAlexander Aring2023-03-061-195/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch removes code parts which was declared deprecated by commit 6b0afc0cc3e9 ("fs: dlm: don't use deprecated timeout features by default"). This contains the following dlm functionality: - start a cancel of a dlm request did not complete after certain timeout: The current way how dlm cancellation works and interfering with other dlm requests triggered by the user can end in an overlapping and returning in -EBUSY. The most user don't handle this case and are unaware that DLM can return such errno in such situation. Due the timeout the user are mostly unaware when this happens. - start a netlink warning messages for user space if dlm requests did not complete after certain timeout: This feature was never being built in the only known dlm user space side. As we are to remove the timeout cancellation feature we can directly remove this feature as well. There might be the possibility to bring the timeout cancellation feature back. However the current way of handling the -EBUSY case which is only a software limitation and not a hardware limitation should be changed. We minimize the current code base in DLM cancellation feature to not have to deal with those existing features while solving the DLM cancellation feature in general. UAPI define DLM_LSFL_TIMEWARN is commented as deprecated and reserved value. We should avoid at first to give it a new meaning but let possible users still compile by keeping this define. In far future we can give this flag a new meaning. The same for the DLM_LKF_TIMEOUT lock request flag. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: remove ls_remove_wait waitqueueAlexander Aring2022-11-081-54/+2
| | | | | | | | | | | | | | | | | | | | | | This patch removes the ls_remove_wait waitqueue handling. The current handling tries to wait before a lookup is send out for a identically resource name which is going to be removed. Hereby the remove message should be send out before the new lookup message. The reason is that after a lookup request and response will actually use the specific remote rsb. A followed remove message would delete the rsb on the remote side but it's still being used. To reach a similar behaviour we simple send the remove message out while the rsb lookup lock is held and the rsb is removed from the toss list. Other find_rsb() calls would never have the change to get a rsb back to live while a remove message will be send out (without holding the lock). This behaviour requires a non-sleepable context which should be provided now and might be the reason why it was not implemented so in the first place. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: allow different allocation context per _create_messageAlexander Aring2022-11-081-12/+19
| | | | | | | | | This patch allows to give the use control about the allocation context based on a per message basis. Currently all messages forced to be created under GFP_NOFS context. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: use a non-static queue for callbacksAlexander Aring2022-11-081-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: use spin lock instead of mutexAlexander Aring2022-11-081-1/+1
| | | | | | | | | There is no need to use a mutex in those hot path sections. We change it to spin lock to serve callbacks more faster by not allowing schedule. The locked sections will not be locked for a long time. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fd: dlm: trace send/recv of dlm message and rcomAlexander Aring2022-11-081-10/+11
| | | | | | | | | | | | | | | | | | | | | | This patch adds tracepoints for send and recv cases of dlm messages and dlm rcom messages. In case of send and dlm message we add the dlm rsb resource name this dlm messages belongs to. This has the advantage to follow dlm messages on a per lock basis. In case of recv message the resource name can be extracted by follow the send message sequence number. The dlm message DLM_MSG_PURGE doesn't belong to a lock request and will not set the resource name in a dlm_message trace. The same for all rcom messages. There is additional handling required for this debugging functionality which is tried to be small as possible. Also the midcomms layer gets aware of lock resource names, for now this is required to make a connection between sequence number and lock resource names. It is for debugging purpose only. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* fs: dlm: remove send repeat remove handlingAlexander Aring2022-11-081-74/+0
| | | | | | | | | | | | | | | | This patch removes the send repeat remove handling. This handling is there to repeatingly DLM_MSG_REMOVE messages in cases the dlm stack thinks it was not received at the first time. In cases of message drops this functionality is necessary, but since the DLM midcomms layer guarantees there are no messages drops between cluster nodes this feature became not strict necessary anymore. Due message delays/processing it could be that two send_repeat_remove() are sent out while the other should be still on it's way. We remove the repeat remove handling because we are sure that the message cannot be dropped due communication errors. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
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