When IO queues are used for parallelized management operations,
e.g. changing cleaning policy, a deadlock may occur due to global
metadata lock interfering with taking request from IO queue,
as they might be run on the same thread. As a workaround using
a management queue specifically for such operations eliminates
this problem.
Signed-off-by: Rafal Stefanowski <rafal.stefanowski@huawei.com>
Initializing metadata in an asynchronous manner will allow to use
parallelization utilities in the future commits
Signed-off-by: Michal Mielewczyk <michal.mielewczyk@intel.com>
Metadata capacity reported by dmesg was actually a memory footprint.
A proper size of metadata is now reported.
Signed-off-by: Krzysztof Majzerowicz-Jaszcz <krzysztof.majzerowicz-jaszcz@intel.com>
This allows to avoid allocating cleaner metadata section and effectively
save up to 20% of metadata memory footprint.
Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
This function must be fixed to work with metadata flapping. Until then
mark as not supported
Signed-off-by: Adam Rutkowski <adam.j.rutkowski@intel.com>
Signed-off-by: Krzysztof Majzerowicz-Jaszcz <krzysztof.majzerowicz-jaszcz@intel.com>
The purpose of this change is not to write superblock to the cache
drive untill all other sections are initilized on disk in attach()
path. Combined with superblock clearing at the erarlier stage of
attach(), this assures there are no residual mappings in the collision
section in case of power failure during attach with pre-existing
metadata.
This is implemented by removing ocf_metadata_flush_all_set_status() step
at the beginning of ocf_metadata_flush_all().
ocf_metadata_flush_all() is called, except for the attach() case described
above, in two cases:
1. at the end of cache load - potentially after cache recovery
2. during detaching cache drive in cache stop.
To make sure there are no regressions in the first case, an explicit
_ocf_mngt_attach_shutdown_status() is added to load pipeline before
ocf_metadata_flush_all(). The second case is always ran after cache
drive is attached, so dirty status bit must have already be written to
the disk.
Signed-off-by: Adam Rutkowski <adam.j.rutkowski@intel.com>
This feature provides double buffering of config sections to prevent
situation when power failure during metadata flush leads to partially
updated metadata. Flapping mechanism makes it always possible to perform
graceful rollback to previous config metadata content in such situation.
Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
To allow the fastest switching from the passive-standby to active mode, the
runtime metadata must be kept 100% synced with the metadata on the drive and in
the RAM thus recovery is required after each collision section update.
To avoid long-lasting recovering of all the cachelines each time the collision
section is being updated, the passive update procedure recovers only those
which have its MD entries on the updated pages.
Signed-off-by: Michal Mielewczyk <michal.mielewczyk@intel.com>
New structure ocf_part is added to contain all the data common for both
user partitions and freelist partition: part_runtime and part_id.
ocf_user_part now contains ocf_part structure as well as pointer to
cleaning partition runtime metadata (moved out from part_runtime) and
user partition config (no change here).
Signed-off-by: Adam Rutkowski <adam.j.rutkowski@intel.com>
Reformat function that calculates how long cache/core is dirty
Update `dirty_for` types in functional tests
Values stored in info structs fields (both in cache and core structs)
are unsigned 64-bits ints but `dirty_for`s were unsigned 32-bits ints.
Use existing function to transform returned value to seconds.
Replace seconds stored in metadata with seconds.
Replacement was done if old value of replaced field was equal to zero.
Acquiring monotonic high precission timestamp is potentially
slow and it makes sense to compare the field's value
to zero before calling atomic function.
Signed-off-by: Slawomir Jankowski <slawomir.jankowski@intel.com>
