kernel/linux.git/fs/dlm/lock.h, branch v6.12.80

dlm: warn about invalid nodeid comparsions

2024-08-08T20:15:07+00:00

This patch adds a warn on if is_master() and dlm_is_removed() checks on invalid nodeid states that are probably not what the caller wants to do here. The is_master() function checking on r->res_nodeid is invalid when it is set to -1, whereas the dlm_is_removed() has a different meaning as "nodeid member" and also 0 is invalid. We run into these cases and this patch changes those cases as we never will run into them. There should be no functional changes as the condition should return the same result. However this patch signals now on caller level that there might be an "extra" case to handle here. Signed-off-by: Alexander Aring Signed-off-by: David Teigland

dlm: change list and timer names

2024-06-10T20:11:46+00:00

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

dlm: drop dlm_scand kthread and use timers

2024-04-16T19:40:27+00:00

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 Signed-off-by: David Teigland

dlm: do not use ref counts for rsb in the toss state

2024-04-16T19:34:39+00:00

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 Signed-off-by: David Teigland

dlm: switch to use rhashtable for rsbs

2024-04-16T19:34:39+00:00

Replace our own hash table with the more advanced rhashtable for keeping rsb structs. Signed-off-by: Alexander Aring Signed-off-by: David Teigland

dlm: use spin_lock_bh for message processing

2024-04-09T16:45:23+00:00

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 Signed-off-by: David Teigland

dlm: convert res_lock to spinlock

2024-04-09T16:44:49+00:00

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 Signed-off-by: David Teigland

dlm: drop mutex use in waiters recovery

2024-04-09T16:44:49+00:00

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 Signed-off-by: David Teigland

dlm: move rsb root_list to ls_recover() stack

2024-04-09T16:44:49+00:00

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 Signed-off-by: David Teigland

fs: dlm: constify receive buffer

2023-08-10T15:33:03+00:00

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 Signed-off-by: David Teigland