[RFC PATCH 00/13] Extedn DAMOS filters for address ranges and

[RFC PATCH 00/13] Extedn DAMOS filters for address ranges and

[SeongJae Park]

There are use cases that need to apply DAMOS schemes to specific address
ranges or DAMON monitoring targets.  NUMA nodes in the physical address
space, special memory objects in the virtual address space, and
monitoring target specific efficient monitoring results snapshot
retrieval could be examples of such use cases.  This patchset extends
DAMOS filters feature for such cases, by implementing two more filter
types, namely address ranges and DAMON monitoring types.

Patches sequence
----------------

The first seven patches are for the address ranges based DAMOS filter.
The first patch implements the filter feature and expose it via DAMON
kernel API.  The second patch further expose the feature to users via
DAMON sysfs interface.  The third and fourth patches implement unit
tests and selftests for the feature.  Three patches (fifth to seventh)
updating the documents follow.

The following six patches are for the DAMON monitoring target based
DAMOS filter.  The eighth patch implements the feature in the core layer
and expose it via DAMON's kernel API.  The ninth patch further expose it
to users via DAMON sysfs interface.  Tenth patch add a selftest, and two
patches (eleventh and twelfth) update documents.

SeongJae Park (13):
  mm/damon/core: introduce address range type damos filter
  mm/damon/sysfs-schemes: support address range type DAMOS filter
  mm/damon/core-test: add a unit test for __damos_filter_out()
  selftests/damon/sysfs: test address range damos filter
  Docs/mm/damon/design: update for address range filters
  Docs/ABI/damon: update for address range DAMOS filter
  Docs/admin-guide/mm/damon/usage: update for address range type DAMOS
    filter
  mm/damon/core: implement target type damos filter
  mm/damon/sysfs-schemes: support target damos filter
  selftests/damon/sysfs: test damon_target filter
  Docs/mm/damon/design: update for DAMON monitoring target type DAMOS
    filter
  Docs/ABI/damon: update for DAMON monitoring target type DAMOS filter
  Docs/admin-guide/mm/damon/usage: update for DAMON monitoring target
    type DAMOS filter

 .../ABI/testing/sysfs-kernel-mm-damon         | 27 +++++-
 Documentation/admin-guide/mm/damon/usage.rst  | 34 +++++---
 Documentation/mm/damon/design.rst             | 24 ++++--
 include/linux/damon.h                         | 28 +++++--
 mm/damon/core-test.h                          | 61 ++++++++++++++
 mm/damon/core.c                               | 62 ++++++++++++++
 mm/damon/sysfs-schemes.c                      | 83 +++++++++++++++++++
 tools/testing/selftests/damon/sysfs.sh        |  5 ++
 8 files changed, 299 insertions(+), 25 deletions(-)

-- 
2.25.1

[RFC PATCH 05/13] Docs/mm/damon/design: update for address range filters

[SeongJae Park]

Update DAMON design document's DAMOS filters section for address range
DAMOS filters.  Because address range filters are handled by the core
layer and it makes difference in schemes tried regions and schemes
statistics, clearly describe it.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 Documentation/mm/damon/design.rst | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/Documentation/mm/damon/design.rst b/Documentation/mm/damon/design.rst
index 4bfdf1d30c4a..134912166f5a 100644
--- a/Documentation/mm/damon/design.rst
+++ b/Documentation/mm/damon/design.rst
@@ -380,12 +380,21 @@ number of filters for each scheme.  Each filter specifies the type of target
 memory, and whether it should exclude the memory of the type (filter-out), or
 all except the memory of the type (filter-in).
 
-As of this writing, anonymous page type and memory cgroup type are supported by
-the feature.  Some filter target types can require additional arguments.  For
-example, the memory cgroup filter type asks users to specify the file path of
-the memory cgroup for the filter.  Hence, users can apply specific schemes to
-only anonymous pages, non-anonymous pages, pages of specific cgroups, all pages
-excluding those of specific cgroups, and any combination of those.
+Currently, anonymous page, memory cgroup, and address range type filters are
+supported by the feature.  Some filter target types can require additional
+arguments.  For example, the memory cgroup filter type asks users to specify
+the file path of the memory cgroup for the filter, while the address range type
+asks the start and end addresses of the range.  Hence, users can apply specific
+schemes to only anonymous pages, non-anonymous pages, pages of specific
+cgroups, all pages excluding those of specific cgroups, pages in specific
+address range, and any combination of those.
+
+To handle filters efficiently, the address range type filter is handled by the
+core layer, while others are handled by operations set.  If a memory region is
+filtered by the core layer-handled filter, it is not counted as the scheme has
+tried to the region.  In contrast, if a memory regions is filtered by an
+operations set layer-handled filter, it is counted as the scheme has tried.
+The difference in accounting leads to changes in the statistics.
 
 
 Application Programming Interface
-- 
2.25.1

[RFC PATCH 06/13] Docs/ABI/damon: update for address range DAMOS filter

[SeongJae Park]

Update DAMON ABI document for address ranges type DAMOS filter files.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 .../ABI/testing/sysfs-kernel-mm-damon         | 20 +++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-damon b/Documentation/ABI/testing/sysfs-kernel-mm-damon
index 3d9aaa1cafa9..0bc074d4618c 100644
--- a/Documentation/ABI/testing/sysfs-kernel-mm-damon
+++ b/Documentation/ABI/testing/sysfs-kernel-mm-damon
@@ -271,8 +271,9 @@ What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/filters/
 Date:		Dec 2022
 Contact:	SeongJae Park <sj@kernel.org>
 Description:	Writing to and reading from this file sets and gets the type of
-		the memory of the interest.  'anon' for anonymous pages, or
-		'memcg' for specific memory cgroup can be written and read.
+		the memory of the interest.  'anon' for anonymous pages,
+		'memcg' for specific memory cgroup, or 'addr' for address range
+		(an open-ended interval) can be written and read.
 
 What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/filters/<F>/memcg_path
 Date:		Dec 2022
@@ -281,6 +282,21 @@ Description:	If 'memcg' is written to the 'type' file, writing to and
 		reading from this file sets and gets the path to the memory
 		cgroup of the interest.
 
+What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/filters/<F>/addr_start
+Date:		Jul 2023
+Contact:	SeongJae Park <sj@kernel.org>
+Description:	If 'addr' is written to the 'type' file, writing to or reading
+		from this file sets or gets the start address of the address
+		range for the filter.
+
+What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/filters/<F>/addr_end
+Date:		Jul 2023
+Contact:	SeongJae Park <sj@kernel.org>
+Description:	If 'addr' is written to the 'type' file, writing to or reading
+		from this file sets or gets the end address of the address
+		range for the filter.
+
+
 What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/filters/<F>/matching
 Date:		Dec 2022
 Contact:	SeongJae Park <sj@kernel.org>
-- 
2.25.1

[RFC PATCH 07/13] Docs/admin-guide/mm/damon/usage: update for address range type DAMOS filter

[SeongJae Park]

Update DAMON usage document for the newly added address range type DAMOS
filter.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 Documentation/admin-guide/mm/damon/usage.rst | 31 +++++++++++++-------
 1 file changed, 20 insertions(+), 11 deletions(-)

diff --git a/Documentation/admin-guide/mm/damon/usage.rst b/Documentation/admin-guide/mm/damon/usage.rst
index 1859dd6c3834..a9cb9949b796 100644
--- a/Documentation/admin-guide/mm/damon/usage.rst
+++ b/Documentation/admin-guide/mm/damon/usage.rst
@@ -363,15 +363,18 @@ number (``N``) to the file creates the number of child directories named ``0``
 to ``N-1``.  Each directory represents each filter.  The filters are evaluated
 in the numeric order.
 
-Each filter directory contains three files, namely ``type``, ``matcing``, and
-``memcg_path``.  You can write one of two special keywords, ``anon`` for
-anonymous pages, or ``memcg`` for specific memory cgroup filtering.  In case of
-the memory cgroup filtering, you can specify the memory cgroup of the interest
-by writing the path of the memory cgroup from the cgroups mount point to
-``memcg_path`` file.  You can write ``Y`` or ``N`` to ``matching`` file to
-filter out pages that does or does not match to the type, respectively.  Then,
-the scheme's action will not be applied to the pages that specified to be
-filtered out.
+Each filter directory contains five files, namely ``type``, ``matcing``,
+``memcg_path``, ``addr_start``, and ``addr_end``.  To ``type`` file, you can
+write one of three special keywords: ``anon`` for anonymous pages, ``memcg``
+for specific memory cgroup, or ``addr`` for specific address range (an
+open-ended interval) filtering.  In case of the memory cgroup filtering, you
+can specify the memory cgroup of the interest by writing the path of the memory
+cgroup from the cgroups mount point to ``memcg_path`` file.  In case of the
+address range filtering, you can specify the start and end address of the range
+to ``addr_start`` and ``addr_end`` files, respectively.  You can write ``Y`` or
+``N`` to ``matching`` file to filter out pages that does or does not match to
+the type, respectively.  Then, the scheme's action will not be applied to the
+pages that specified to be filtered out.
 
 For example, below restricts a DAMOS action to be applied to only non-anonymous
 pages of all memory cgroups except ``/having_care_already``.::
@@ -385,8 +388,14 @@ pages of all memory cgroups except ``/having_care_already``.::
     echo /having_care_already > 1/memcg_path
     echo N > 1/matching
 
-Note that filters are currently supported only when ``paddr``
-`implementation <sysfs_contexts>` is being used.
+Note that ``anon`` and ``memcg`` filters are currently supported only when
+``paddr`` `implementation <sysfs_contexts>` is being used.
+
+Also, memory regions that are filtered out by ``addr`` filters are not counted
+as the scheme has tried to those, while regions that filtered out by other type
+filters are counted as the scheme has tried to.  The difference is applied to
+:ref:`stats <damos_stats>` and :ref:`tried regions
+<sysfs_schemes_tried_regions>`.
 
 .. _sysfs_schemes_stats:
 
-- 
2.25.1

[RFC PATCH 11/13] Docs/mm/damon/design: update for DAMON monitoring target type DAMOS filter

[SeongJae Park]

Update DAMON design document for the newly added DAMON monitoring target
type DAMOS filter.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 Documentation/mm/damon/design.rst | 33 +++++++++++++++++--------------
 1 file changed, 18 insertions(+), 15 deletions(-)

diff --git a/Documentation/mm/damon/design.rst b/Documentation/mm/damon/design.rst
index 134912166f5a..a20383d01a95 100644
--- a/Documentation/mm/damon/design.rst
+++ b/Documentation/mm/damon/design.rst
@@ -380,21 +380,24 @@ number of filters for each scheme.  Each filter specifies the type of target
 memory, and whether it should exclude the memory of the type (filter-out), or
 all except the memory of the type (filter-in).
 
-Currently, anonymous page, memory cgroup, and address range type filters are
-supported by the feature.  Some filter target types can require additional
-arguments.  For example, the memory cgroup filter type asks users to specify
-the file path of the memory cgroup for the filter, while the address range type
-asks the start and end addresses of the range.  Hence, users can apply specific
-schemes to only anonymous pages, non-anonymous pages, pages of specific
-cgroups, all pages excluding those of specific cgroups, pages in specific
-address range, and any combination of those.
-
-To handle filters efficiently, the address range type filter is handled by the
-core layer, while others are handled by operations set.  If a memory region is
-filtered by the core layer-handled filter, it is not counted as the scheme has
-tried to the region.  In contrast, if a memory regions is filtered by an
-operations set layer-handled filter, it is counted as the scheme has tried.
-The difference in accounting leads to changes in the statistics.
+Currently, anonymous page, memory cgroup, address range, and DAMON monitoring
+target type filters are supported by the feature.  Some filter target types
+require additional arguments.  The memory cgroup filter type asks users to
+specify the file path of the memory cgroup for the filter.  The address range
+type asks the start and end addresses of the range.  The DAMON monitoring
+target type asks the index of the target from the context's monitoring targets
+list.  Hence, users can apply specific schemes to only anonymous pages,
+non-anonymous pages, pages of specific cgroups, all pages excluding those of
+specific cgroups, pages in specific address range, pages in specific DAMON
+monitoring targets, and any combination of those.
+
+To handle filters efficiently, the address range and DAMON monitoring target
+type filters are handled by the core layer, while others are handled by
+operations set.  If a memory region is filtered by a core layer-handled filter,
+it is not counted as the scheme has tried to the region.  In contrast, if a
+memory regions is filtered by an operations set layer-handled filter, it is
+counted as the scheme has tried.  The difference in accounting leads to changes
+in the statistics.
 
 
 Application Programming Interface
-- 
2.25.1

[RFC PATCH 12/13] Docs/ABI/damon: update for DAMON monitoring target type DAMOS filter

[SeongJae Park]

Update DAMON ABI document for the newly added DAMON monitoring target
type DAMOS filter.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 Documentation/ABI/testing/sysfs-kernel-mm-damon | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-damon b/Documentation/ABI/testing/sysfs-kernel-mm-damon
index 0bc074d4618c..334352d198f8 100644
--- a/Documentation/ABI/testing/sysfs-kernel-mm-damon
+++ b/Documentation/ABI/testing/sysfs-kernel-mm-damon
@@ -272,8 +272,9 @@ Date:		Dec 2022
 Contact:	SeongJae Park <sj@kernel.org>
 Description:	Writing to and reading from this file sets and gets the type of
 		the memory of the interest.  'anon' for anonymous pages,
-		'memcg' for specific memory cgroup, or 'addr' for address range
-		(an open-ended interval) can be written and read.
+		'memcg' for specific memory cgroup, 'addr' for address range
+		(an open-ended interval), or 'target' for DAMON monitoring
+		target can be written and read.
 
 What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/filters/<F>/memcg_path
 Date:		Dec 2022
@@ -296,6 +297,12 @@ Description:	If 'addr' is written to the 'type' file, writing to or reading
 		from this file sets or gets the end address of the address
 		range for the filter.
 
+What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/filters/<F>/target_idx
+Date:		Dec 2022
+Contact:	SeongJae Park <sj@kernel.org>
+Description:	If 'target' is written to the 'type' file, writing to or
+		reading from this file sets or gets the index of the DAMON
+		monitoring target of the interest.
 
 What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/filters/<F>/matching
 Date:		Dec 2022
-- 
2.25.1

[RFC PATCH 13/13] Docs/admin-guide/mm/damon/usage: update for DAMON monitoring target type DAMOS filter

[SeongJae Park]

Update DAMON usage document for newly added DAMON monitoring target type
DAMOS filter.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 Documentation/admin-guide/mm/damon/usage.rst | 37 +++++++++++---------
 1 file changed, 20 insertions(+), 17 deletions(-)

diff --git a/Documentation/admin-guide/mm/damon/usage.rst b/Documentation/admin-guide/mm/damon/usage.rst
index a9cb9949b796..084f0a32b421 100644
--- a/Documentation/admin-guide/mm/damon/usage.rst
+++ b/Documentation/admin-guide/mm/damon/usage.rst
@@ -363,18 +363,21 @@ number (``N``) to the file creates the number of child directories named ``0``
 to ``N-1``.  Each directory represents each filter.  The filters are evaluated
 in the numeric order.
 
-Each filter directory contains five files, namely ``type``, ``matcing``,
-``memcg_path``, ``addr_start``, and ``addr_end``.  To ``type`` file, you can
-write one of three special keywords: ``anon`` for anonymous pages, ``memcg``
-for specific memory cgroup, or ``addr`` for specific address range (an
-open-ended interval) filtering.  In case of the memory cgroup filtering, you
-can specify the memory cgroup of the interest by writing the path of the memory
-cgroup from the cgroups mount point to ``memcg_path`` file.  In case of the
-address range filtering, you can specify the start and end address of the range
-to ``addr_start`` and ``addr_end`` files, respectively.  You can write ``Y`` or
-``N`` to ``matching`` file to filter out pages that does or does not match to
-the type, respectively.  Then, the scheme's action will not be applied to the
-pages that specified to be filtered out.
+Each filter directory contains six files, namely ``type``, ``matcing``,
+``memcg_path``, ``addr_start``, ``addr_end``, and ``target_idx``.  To ``type``
+file, you can write one of four special keywords: ``anon`` for anonymous pages,
+``memcg`` for specific memory cgroup, ``addr`` for specific address range (an
+open-ended interval), or ``target`` for specific DAMON monitoring target
+filtering.  In case of the memory cgroup filtering, you can specify the memory
+cgroup of the interest by writing the path of the memory cgroup from the
+cgroups mount point to ``memcg_path`` file.  In case of the address range
+filtering, you can specify the start and end address of the range to
+``addr_start`` and ``addr_end`` files, respectively.  For the DAMON monitoring
+target filtering, you can specify the index of the target between the list of
+the DAMON context's monitoring targets list to ``target_idx`` file.  You can
+write ``Y`` or ``N`` to ``matching`` file to filter out pages that does or does
+not match to the type, respectively.  Then, the scheme's action will not be
+applied to the pages that specified to be filtered out.
 
 For example, below restricts a DAMOS action to be applied to only non-anonymous
 pages of all memory cgroups except ``/having_care_already``.::
@@ -391,11 +394,11 @@ pages of all memory cgroups except ``/having_care_already``.::
 Note that ``anon`` and ``memcg`` filters are currently supported only when
 ``paddr`` `implementation <sysfs_contexts>` is being used.
 
-Also, memory regions that are filtered out by ``addr`` filters are not counted
-as the scheme has tried to those, while regions that filtered out by other type
-filters are counted as the scheme has tried to.  The difference is applied to
-:ref:`stats <damos_stats>` and :ref:`tried regions
-<sysfs_schemes_tried_regions>`.
+Also, memory regions that are filtered out by ``addr`` or ``target`` filters
+are not counted as the scheme has tried to those, while regions that filtered
+out by other type filters are counted as the scheme has tried to.  The
+difference is applied to :ref:`stats <damos_stats>` and
+:ref:`tried regions <sysfs_schemes_tried_regions>`.
 
 .. _sysfs_schemes_stats:
 
-- 
2.25.1