If partition's occupancy limit is reached, cachelines should be evicted from
request's target partition.
Information whether particular partition eviction should be triggered is
carried as a flag by request which triggered eviction.
Signed-off-by: Michal Mielewczyk <michal.mielewczyk@intel.com>
Add second pass of write invalidate. It is necessary only
if concurrent I/O had inserted target LBAs to cache after
WI request did traversation. These LBAs might have been
written by WI request behind the concurrent I/O's back,
resulting in making these sectors effectively invalid.
In this case we must update these sectors' metadata to
reflect this. However we won't know about this after we
traverse the request again - hence calling ocf_write_wi
again with req->wi_second_pass set to indicate that this
is the second pass (core write should be skipped).
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>
Promotion policy is supposed to perform ALRU noise filtering by
eliminating one-hit wonders being added to cache and polluting it.
Signed-off-by: Jan Musial <jan.musial@intel.com>
Write-only cache mode is similar to writeback, however read
operations do not promote data to cache. Reads are mostly serviced
by the core device, only dirty sectors are fetched from the cache.
Signed-off-by: Adam Rutkowski <adam.j.rutkowski@intel.com>
ocf_request has always been first class citizen in OCF,
so lets place it along with another essential objects.
Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
- Queue allocation is now separated from starting cache.
- Queue can be created and destroyed in runtime.
- All queue ops accept queue handle instead of queue id.
- Cache stores queues as list instead of array.
Signed-off-by: Michal Mielewczyk <michal.mielewczyk@intel.com>
Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>