linux-stable.git/include/linux/damon.h, branch v5.17.7

mm/damon: move the implementation of damon_insert_region to damon.h

2022-01-15T14:30:33+00:00

Usually, inline function is declared static since it should sit between
storage and type.  And implement it in a header file if used by multiple
files.

And this change also fixes compile issue when backport damon to 5.10.

  mm/damon/vaddr.c: In function `damon_va_evenly_split_region':
  ./include/linux/damon.h:425:13: error: inlining failed in call to `always_inline' `damon_insert_region': function body not available
  425 | inline void damon_insert_region(struct damon_region *r,
      | ^~~~~~~~~~~~~~~~~~~
  mm/damon/vaddr.c:86:3: note: called from here
  86 | damon_insert_region(n, r, next, t);
     | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Link: https://lkml.kernel.org/r/20211223085703.6142-1-guoqing.jiang@linux.dev
Signed-off-by: Guoqing Jiang 
Reviewed-by: SeongJae Park 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/damon/schemes: account how many times quota limit has exceeded

2022-01-15T14:30:33+00:00

If the time/space quotas of a given DAMON-based operation scheme is too
small, the scheme could show unexpectedly slow progress.  However, there
is no good way to notice the case in runtime.  This commit extends the
DAMOS stat to provide how many times the quota limits exceeded so that
the users can easily notice the case and tune the scheme.

Link: https://lkml.kernel.org/r/20211210150016.35349-3-sj@kernel.org
Signed-off-by: SeongJae Park 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/damon/schemes: account scheme actions that successfully applied

2022-01-15T14:30:32+00:00

Patch series "mm/damon/schemes: Extend stats for better online analysis and tuning".

To help online access pattern analysis and tuning of DAMON-based
Operation Schemes (DAMOS), DAMOS provides simple statistics for each
scheme.  Introduction of DAMOS time/space quota further made the tuning
easier by making the risk management easier.  However, that also made
understanding of the working schemes a little bit more difficult.

For an example, progress of a given scheme can now be throttled by not
only the aggressiveness of the target access pattern, but also the
time/space quotas.  So, when a scheme is showing unexpectedly slow
progress, it's difficult to know by what the progress of the scheme is
throttled, with currently provided statistics.

This patchset extends the statistics to contain some metrics that can be
helpful for such online schemes analysis and tuning (patches 1-2),
exports those to users (patches 3 and 5), and add documents (patches 4
and 6).

This patch (of 6):

DAMON-based operation schemes (DAMOS) stats provide only the number and
the amount of regions that the action of the scheme has tried to be
applied.  Because the action could be failed for some reasons, the
currently provided information is sometimes not useful or convenient
enough for schemes profiling and tuning.  To improve this situation,
this commit extends the DAMOS stats to provide the number and the amount
of regions that the action has successfully applied.

Link: https://lkml.kernel.org/r/20211210150016.35349-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20211210150016.35349-2-sj@kernel.org
Signed-off-by: SeongJae Park 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/damon: remove a mistakenly added comment for a future feature

2022-01-15T14:30:32+00:00

Due to a mistake in patches reordering, a comment for a future feature
called 'arbitrary monitoring target support'[1], which is still under
development, has added.  Because it only introduces confusion and we
don't have a plan to post the patches soon, this commit removes the
mistakenly added part.

[1] https://lore.kernel.org/linux-mm/20201215115448.25633-3-sjpark@amazon.com/

Link: https://lkml.kernel.org/r/20211209131806.19317-7-sj@kernel.org
Fixes: 1f366e421c8f ("mm/damon/core: implement DAMON-based Operation Schemes (DAMOS)")
Signed-off-by: SeongJae Park 
Cc: Jonathan Corbet 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/damon: convert macro functions to static inline functions

2022-01-15T14:30:32+00:00

Patch series "mm/damon: Misc cleanups".

This patchset contains miscellaneous cleanups for DAMON's macro
functions and documentation.

This patch (of 6):

This commit converts macro functions in DAMON to static inline functions,
for better type checking, code documentation, etc[1].

[1] https://lore.kernel.org/linux-mm/20211202151213.6ec830863342220da4141bc5@linux-foundation.org/

Link: https://lkml.kernel.org/r/20211209131806.19317-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20211209131806.19317-2-sj@kernel.org
Signed-off-by: SeongJae Park 
Cc: Jonathan Corbet 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/damon: modify damon_rand() macro to static inline function

2022-01-15T14:30:32+00:00

damon_rand() cannot be implemented as a macro.

Example:
	damon_rand(a++, b);

The value of 'a' will be incremented twice, This is obviously
unreasonable, So there fix it.

Link: https://lkml.kernel.org/r/110ffcd4e420c86c42b41ce2bc9f0fe6a4f32cd3.1638795127.git.xhao@linux.alibaba.com
Fixes: b9a6ac4e4ede ("mm/damon: adaptively adjust regions")
Signed-off-by: Xin Hao 
Reported-by: Andrew Morton 
Reviewed-by: SeongJae Park 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/damon: move damon_rand() definition into damon.h

2022-01-15T14:30:32+00:00

damon_rand() is called in three files:damon/core.c, damon/ paddr.c,
damon/vaddr.c, i think there is no need to redefine this twice, So move
it to damon.h will be a good choice.

Link: https://lkml.kernel.org/r/20211202075859.51341-1-xhao@linux.alibaba.com
Signed-off-by: Xin Hao 
Reviewed-by: SeongJae Park 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/damon: remove some unneeded function definitions in damon.h

2022-01-15T14:30:32+00:00

In damon.h some func definitions about VA & PA can only be used in its
own file, so there no need to define in the header file, and the header
file will look cleaner.

If other files later need these functions, the prototypes can be added
to damon.h at that time.

[sj@kernel.org: remove unnecessary function prototype position changes]
 Link: https://lkml.kernel.org/r/20211118114827.20052-1-sj@kernel.org

Link: https://lkml.kernel.org/r/45fd5b3ef6cce8e28dbc1c92f9dc845ccfc949d7.1636989871.git.xhao@linux.alibaba.com
Signed-off-by: Xin Hao 
Signed-off-by: SeongJae Park 
Reviewed-by: SeongJae Park 
Cc: Muchun Song 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/damon: remove return value from before_terminate callback

2021-11-06T20:30:46+00:00

Since the return value of 'before_terminate' callback is never used, we
make it have no return value.

Link: https://lkml.kernel.org/r/20211029005023.8895-1-changbin.du@gmail.com
Signed-off-by: Changbin Du 
Reviewed-by: SeongJae Park 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/damon: simplify stop mechanism

2021-11-06T20:30:46+00:00

A kernel thread can exit gracefully with kthread_stop().  So we don't
need a new flag 'kdamond_stop'.  And to make sure the task struct is not
freed when accessing it, get reference to it before termination.

Link: https://lkml.kernel.org/r/20211027130517.4404-1-changbin.du@gmail.com
Signed-off-by: Changbin Du 
Reviewed-by: SeongJae Park 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds