This is a suboptimal solution to CAS on top of MD RAID1 device. If using
only submit_bio API RAID1 would process all IOs in single thread.
Plugging bypasses this thread and processess IOs in blk_finish_plug
caller context improving performance drastically.
Testing showed no negative impact to other usecases and it's a thing
that Linux does in AIO, so it's vetted and proven to work.
Signed-off-by: Jan Musial <jan.musial@intel.com>
All the operations on `count` are performed under the lock thus it doesn't need
to be atomic.
Signed-off-by: Michal Mielewczyk <michal.mielewczyk@intel.com>
Some helper threads are created at the very beginning of cache start/stop
operations, but they are used only after OCF start/stop finishes, which
may take significant amount of time. Kernel by default creates threads
that wait for the first wake up in uninterruptible state, which may trigger
hung task warning if the first wake up is called more than 120 seconds
after thread creation. To mitigate this problem we create lazy thread
abstraction that waits for a wake up in interruptible state.
Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
OCF cannot allocate request map bigger than 4MiB (due to kmalloc
limitations), thus we need to split bigger IOs into series smaller
ones to reduce request map size.
Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
It's defined on every single supported kernel, so there is actually no need
for this define at all.
Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>
This patch fixes adding core after core addition failure.
The queue wasn't cleaned before and following core addition cannot
re-initialize queue properly.
Signed-off-by: Slawomir Jankowski <slawomir.jankowski@intel.com>
In case of initial flush error stop is aborted. In case
of failure during the second flush, appropriate error
message is presetned to the user.
Signed-off-by: Adam Rutkowski <adam.j.rutkowski@intel.com>
Don't remove inactive core if it has dirt cache lines assigned unless `force`
flag is specified.
Signed-off-by: Michal Mielewczyk <michal.mielewczyk@intel.com>
The data->size field can be initialized to a lower value than bio->bi_vcnt,
if the bio is split. The bio_for_each_segment then iterates based on the original
indexes and the mismatch eventually causes a BUG_ON.
Fixes#714
Signed-off-by: Kozlowski Mateusz <mateusz.kozlowski@intel.com>
If time is counted in jiffies, machine reboot brokes `dirty for`
statistic for caches loaded at boot. The counter overflows and
`dirty for` shows some huge values.
Cast ticks to unsigned long.
Add necessary header.
Move `env_msleep` to `TIME` subgroup of header.
Move `env_time_after` below time converting functions.
Signed-off-by: Slawomir Jankowski <slawomir.jankowski@intel.com>
