wireguard-linux/fs/dlm/lock.c, branch update-toolchain

dlm: use rcu to avoid an extra rsb struct lookup

2024-06-10T20:26:03Z

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 Signed-off-by: David Teigland

dlm: fix add_scan and del_scan usage

2024-06-10T20:21:28Z

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

dlm: change list and timer names

2024-06-10T20:11:46Z

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: move lkb idr to xarray datastructure

2024-05-31T16:04:54Z

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 Signed-off-by: David Teigland

dlm: drop own rsb pre allocation mechanism

2024-05-31T16:04:54Z

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 Signed-off-by: David Teigland

dlm: don't kref_init rsbs created for toss list

2024-05-31T16:04:54Z

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 Signed-off-by: David Teigland

dlm: fix sleep in atomic context

2024-04-17T19:20:04Z

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 Closes: https://lore.kernel.org/gfs2/9ad928eb-2ece-4ad9-a79c-d2bce228e4bc@moroto.mountain/ Signed-off-by: Alexander Aring Signed-off-by: David Teigland

dlm: use rwlock for lkbidr

2024-04-16T19:45:57Z

Convert the lock for lkbidr to an rwlock. Most idr lookups will use the read lock. Signed-off-by: Alexander Aring Signed-off-by: David Teigland

dlm: use rwlock for rsb hash table

2024-04-16T19:45:31Z

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 Signed-off-by: David Teigland

dlm: drop dlm_scand kthread and use timers

2024-04-16T19:40:27Z

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