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>
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>
Based on 1 normalized pattern(s):
this copyrighted material is made available to anyone wishing to use
modify copy or redistribute it subject to the terms and conditions
of the gnu general public license v 2
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 45 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170027.342746075@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This function was only for debugging. It would be
called in a condition that should not happen, and
should probably have been removed from the final
version of the original commit.
Remove it because it does mutex lock under spin lock.
Signed-off-by: David Teigland <teigland@redhat.com>
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>
Slot numbers are assigned to nodes when they join the lockspace.
The slot number chosen is the minimum unused value starting at 1.
Once a node is assigned a slot, that slot number will not change
while the node remains a lockspace member. If the node leaves
and rejoins it can be assigned a new slot number.
A new generation number is also added to a lockspace. It is
set and incremented during each recovery along with the slot
collection/assignment.
The slot numbers will be passed to gfs2 which will use them as
journal id's.
Signed-off-by: David Teigland <teigland@redhat.com>
Introduce a per-lockspace rwsem that's held in read mode by dlm_recv
threads while working in the dlm. This allows dlm_recv activity to be
suspended when the lockspace transitions to, from and between recovery
cycles.
The specific bug prompting this change is one where an in-progress
recovery cycle is aborted by a new recovery cycle. While dlm_recv was
processing a recovery message, the recovery cycle was aborted and
dlm_recoverd began cleaning up. dlm_recv decremented recover_locks_count
on an rsb after dlm_recoverd had reset it to zero. This is fixed by
suspending dlm_recv (taking write lock on the rwsem) before aborting the
current recovery.
The transitions to/from normal and recovery modes are simplified by using
this new ability to block dlm_recv. The switch from normal to recovery
mode means dlm_recv goes from processing locking messages, to saving them
for later, and vice versa. Races are avoided by blocking dlm_recv when
setting the flag that switches between modes.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@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>
