linux-stable.git/fs/dlm, branch v6.10

dlm: return -ENOMEM if ls_recover_buf fails

2024-04-23T21:08:55+00:00

This patch fixes to return -ENOMEM in case of an allocation failure that
was forgotten to change in commit 6c648035cbe7 ("dlm: switch to use
rhashtable for rsbs").

Reported-by: kernel test robot 
Reported-by: Dan Carpenter 
Closes: https://lore.kernel.org/r/202404200536.jGi6052v-lkp@intel.com/
Fixes: 6c648035cbe7 ("dlm: switch to use rhashtable for rsbs")
Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland

dlm: fix sleep in atomic context

2024-04-17T19:20:04+00:00

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

2024-04-16T19:45:57+00:00

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

2024-04-16T19:45:31+00:00

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

2024-04-16T19:40:27+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: add rsb lists for iteration

2024-04-16T19:33:25+00:00

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 
Signed-off-by: David Teigland

dlm: merge toss and keep hash table lists into one list

2024-04-16T18:49:13+00:00

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 
Signed-off-by: David Teigland

dlm: change to single hashtable lock

2024-04-16T18:46:41+00:00

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 
Signed-off-by: David Teigland