Remove the dir hash table (dirtbl), and use
the rsb hash table (rsbtbl) as the resource
directory. It has always been an unnecessary
duplication of information.
This improves efficiency by using a single rsbtbl
lookup in many cases where both rsbtbl and dirtbl
lookups were needed previously.
This eliminates the need to handle cases of rsbtbl
and dirtbl being out of sync.
In many cases there will be memory savings because
the dir hash table no longer exists.
Signed-off-by: David Teigland <teigland@redhat.com>
The function used to find an rsb during directory
recovery was searching the single linear list of
rsb's. This wasted a lot of time compared to
using the standard hash table to find the rsb.
Signed-off-by: David Teigland <teigland@redhat.com>
Put all the calls to recovery barriers in the same function
to clarify where they each happen. Should not change any behavior.
Also modify some recovery debug lines to make them consistent.
Signed-off-by: David Teigland <teigland@redhat.com>
Replace all GFP_KERNEL and ls_allocation with GFP_NOFS.
ls_allocation would be GFP_KERNEL for userland lockspaces
and GFP_NOFS for file system lockspaces.
It was discovered that any lockspaces on the system can
affect all others by triggering memory reclaim in the
file system which could in turn call back into the dlm
to acquire locks, deadlocking dlm threads that were
shared by all lockspaces, like dlm_recv.
Signed-off-by: David Teigland <teigland@redhat.com>
Change some GFP_KERNEL allocations to use either GFP_NOFS or
ls_allocation (when available) which the fs sets to GFP_NOFS.
The point is to prevent allocations from going back into the
cluster fs in places where that might lead to deadlock.
Signed-off-by: David Teigland <teigland@redhat.com>
The ls_dirtbl[].lock was an rwlock, but since it was only used in write
mode a spinlock will suffice.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
... those can happen and BUG() from DLM_ASSERT() in allocate_direntry() is
not a good way to handle them.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Teigland <teigland@redhat.com>
To prevent the master of an rsb from changing rapidly, an unused rsb is kept
on the "toss list" for a period of time to be reused. The toss list was
being cleared completely for each recovery, which is unnecessary. Much of
the benefit of the toss list can be maintained if nodes keep rsb's in their
toss list that they are the master of. These rsb's need to be included
when the resource directory is rebuilt during recovery.
Signed-off-by: David Teigland <teigland@redhat.com>
The dlm functions in memory.c should use the dlm_ prefix. Also, use
kzalloc/kfree directly for dlm_direntry's, removing the wrapper functions.
Signed-off-by: David Teigland <teigland@redhat.com>
This is the core of the distributed lock manager which is required
to use GFS2 as a cluster filesystem. It is also used by CLVM and
can be used as a standalone lock manager independantly of either
of these two projects.
It implements VAX-style locking modes.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
David Teigland