Adding locks to assure partition list consistency. Partition
lists is typically modified under cacheline or hash bucket lock.
This is not sufficient synchronization as adding/removing cacheline
from partition list affects neighbouring cachelines state as well.
Signed-off-by: Adam Rutkowski <adam.j.rutkowski@intel.com>
There is one RW lock per hash bucket. Write lock is required
to map cacheline, read lock is sufficient for traversing.
Hash bucket locks are always acquired under global metadata
read lock. This assures mutual exclusion with eviction and
management paths, where global metadata write lock is held.
Signed-off-by: Adam Rutkowski <adam.j.rutkowski@intel.com>
Global free cacheline list is divided into a set of freelists, one
per execution context. When attempting to map addres to cache, first
the freelist for current execution context is considered (fast path).
If current execution context freelist is empty (fast path failure),
mapping function attempts to get freelist from other execution context
list (slow path).
The purpose of this change is improve concurrency in freelist access.
It is part of fine granularity metadata lock implementation.
Signed-off-by: Adam Rutkowski <adam.j.rutkowski@intel.com>
Metadata layout (seq / striping) is already encapsulated
in ocf_metadata_layout_iface, no need to double this logic
in freelist initialization.
Signed-off-by: Adam Rutkowski <adam.j.rutkowski@intel.com>
