DAMON sysfs interface implements multiple quota auto-tuning goals on its
level since the DAMOS core logic was supporting only single goal. Now the
core logic supports multiple goals on its level. Update DAMON sysfs
interface to reuse the core logic and drop unnecessary duplicated multiple
goals implementation.
Link: https://lkml.kernel.org/r/20240219194431.159606-10-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Implement yet another kdamond 'state' file input command, namely
'update_schemes_effective_quotas'. If it is written, the
'effective_bytes' files of the kdamond will be updated to provide the
current effective size quota of each scheme in bytes.
Link: https://lkml.kernel.org/r/20240219194431.159606-4-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
DAMON sysfs interface need to access kdamond-touching data for some of
kdamond user commands. It uses ->after_aggregation() kdamond callback to
safely access the data in the case. It had to use the aggregation
interval callback because that was the only callback that users can access
complete monitoring results.
Since patch series "mm/damon: provide pseudo-moving sum based access
rate", which starts from commit 78fbfb155d ("mm/damon/core: define and
use a dedicated function for region access rate update"), DAMON provides
good-to-use quality moitoring results for every sampling interval. It
aims to help users who need to quickly retrieve the monitoring results.
When the aggregation interval is set too long and therefore waiting for
the aggregation interval can degrade user experience, or when the access
pattern is expected to be significantly changed[1] could be such cases.
However, because DAMON sysfs interface is still handling the commands per
aggregation interval, the end user cannot get the benefit. Update DAMON
sysfs interface to handle kdamond commands for every sampling interval if
applicable. Specifically, all kdamond data accessing commands except
'commit' command are applicable.
[1] https://lore.kernel.org/r/20240129121316.GA9706@cuiyangpei
Link: https://lkml.kernel.org/r/20240206025158.203097-1-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: xiongping1 <xiongping1@xiaomi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
DAMON_SYSFS assumes all schemes will be applied for at least one DAMON
monitoring results snapshot within one aggregation interval, or makes no
sense to wait for it while DAMON is deactivated by the watermarks. That
for deactivated status still makes sense, but the aggregation interval
based assumption is invalid now because each scheme can has its own apply
interval. For schemes having larger than the aggregation or watermarks
check interval, DAMOS tried regions update request can be finished without
the update. Avoid the case by explicitly checking the status of the
schemes tried regions update and watermarks based DAMON deactivation.
Link: https://lkml.kernel.org/r/20231012192256.33556-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Using tried_regions/total_bytes file, users can efficiently retrieve the
total size of memory regions having specific access pattern. However,
DAMON sysfs interface in kernel still populates all the infomration on the
tried_regions subdirectories. That means the kernel part overhead for the
construction of tried regions directories still exists. To remove the
overhead, implement yet another command input for 'state' DAMON sysfs
file. Writing the input to the file makes DAMON sysfs interface to update
only the total_bytes file.
Link: https://lkml.kernel.org/r/20230802213222.109841-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Implement the code for filling the data of 'tried_regions' DAMON sysfs
directory. With this commit, DAMON sysfs interface users can write a
special keyword, 'update_schemes_tried_regions' to the corresponding
'state' file of the kdamond. Then, DAMON sysfs interface will collect the
tried regions information using the 'before_damos_apply()' callback for
one aggregation interval and populate scheme region directories with the
values.
[sj@kernel.org: skip tried regions update if the scheme directory was removed]
Link: https://lkml.kernel.org/r/20221114182954.4745-2-sj@kernel.org
Link: https://lkml.kernel.org/r/20221101220328.95765-5-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The implementation of unsigned long type range directories can be reused
by multiple DAMON sysfs directories including those for DAMON-based
Operation Schemes and the range of number of monitoring regions. Move the
code into the files for DAMON sysfs common logics.
Link: https://lkml.kernel.org/r/20221026225943.100429-9-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
DAMON sysfs interface is implemented in a single file, sysfs.c, which has
about 2,800 lines of code. As the interface is hierarchical and some of
the code can be reused by different hierarchies, it would make more sense
to split out the implementation into common parts and different parts in
multiple files. As the beginning of the work, create files for common
code and move the global mutex for directories modifications protection
into the new file.
Link: https://lkml.kernel.org/r/20221026225943.100429-8-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
