mm/damon: misc cleanups

Yet another round of miscellaneous DAMON cleanups.

SeongJae Park (6):
samples/damon/wsse: rename to have damon_sample_ prefix samples/damon/prcl: rename to have damon_sample_ prefix samples/damon/mtier: rename to have damon_sample_ prefix mm/damon/sysfs: use DAMON core API damon_is_running() mm/damon/sysfs: don't hold kdamond_lock in before_terminate() Docs/mm/damon/maintainer-profile: update for mm-new tree

 Documentation/mm/damon/maintainer-profile.rst | 35 ++++++++++---------
 include/linux/damon.h                         |  1 +
 mm/damon/core.c                               |  8 ++++-
 mm/damon/sysfs.c                              | 16 ++-------
 samples/damon/mtier.c                         |  5 +++
 samples/damon/prcl.c                          |  5 +++
 samples/damon/wsse.c                          |  5 +++
 7 files changed, 44 insertions(+), 31 deletions(-)

base-commit: 486593f91f44f469c920e73a4ef451d9bbbf400e

2.39.5

DAMON sample module, wsse has its name 'wsse'. It could conflict with future modules, and not very easy to identify it by name. Use a prefix, "damon_sample_" for the name.

Note that this could break users if they depend on the old name. But it is just a sample, so no such usage is expected, or known. Even if such usage exists, updating it for the new name should be straightforward.

---
 samples/damon/wsse.c | 5 +++++
 1 file changed, 5 insertions(+)

index e20238a249e7..1e8969a0a626 100644
@@ -12,6 +12,11 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 
+#ifdef MODULE_PARAM_PREFIX
+#undef MODULE_PARAM_PREFIX
+#endif
+#define MODULE_PARAM_PREFIX "damon_sample_wsse."
+
 static int target_pid __read_mostly;
 module_param(target_pid, int, 0600);
 

2.39.5

DAMON sample module, prcl has its name 'prcl'. It could conflict with future modules, and not very easy to identify it by name. Use a prefix, "damon_sample_" for the name.

Note that this could break users if they depend on the old name. But it is just a sample, so no such usage is expected, or known. Even if such usage exists, updating it for the new name should be straightforward.

---
 samples/damon/prcl.c | 5 +++++
 1 file changed, 5 insertions(+)

index 5597e6a08ab2..447ccba09e8a 100644
@@ -11,6 +11,11 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 
+#ifdef MODULE_PARAM_PREFIX
+#undef MODULE_PARAM_PREFIX
+#endif
+#define MODULE_PARAM_PREFIX "damon_sample_prcl."
+
 static int target_pid __read_mostly;
 module_param(target_pid, int, 0600);
 

2.39.5

DAMON sample module, mtier has its name 'mtier'. It could conflict with future modules, and not very easy to identify it by name. Use a prefix, "damon_sample_" for the name.

Note that this could break users if they depend on the old name. But it is just a sample, so no such usage is expected, or known. Even if such usage exists, updating it for the new name should be straightforward.

---
 samples/damon/mtier.c | 5 +++++
 1 file changed, 5 insertions(+)

index 97892ade7f31..af168e887f73 100644
@@ -12,6 +12,11 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 
+#ifdef MODULE_PARAM_PREFIX
+#undef MODULE_PARAM_PREFIX
+#endif
+#define MODULE_PARAM_PREFIX "damon_sample_mtier."
+
 static unsigned long node0_start_addr __read_mostly;
 module_param(node0_start_addr, ulong, 0600);
 

2.39.5

DAMON core implements a static function to see if a given DAMON context is running. DAMON sysfs interface is implementing the same one on its own. Make the core function non-static and reuse it from the DAMON sysfs interface.

---
 include/linux/damon.h |  1 +
 mm/damon/core.c       |  8 +++++++-
 mm/damon/sysfs.c      | 14 ++------------
 3 files changed, 10 insertions(+), 13 deletions(-)

index bb58e36f019e..e1fea3119538 100644
@@ -934,6 +934,7 @@ static inline unsigned int damon_max_nr_accesses(const struct damon_attrs *attrs
 
 int damon_start(struct damon_ctx **ctxs, int nr_ctxs, bool exclusive);
 int damon_stop(struct damon_ctx **ctxs, int nr_ctxs);
+bool damon_is_running(struct damon_ctx *ctx);
 
 int damon_call(struct damon_ctx *ctx, struct damon_call_control *control);
 int damos_walk(struct damon_ctx *ctx, struct damos_walk_control *control);

index dc0ee2dd55d3..5357a18066b0 100644
@@ -1311,7 +1311,13 @@ int damon_stop(struct damon_ctx **ctxs, int nr_ctxs)
 	return err;
 }
 
-static bool damon_is_running(struct damon_ctx *ctx)
+/**
+ * damon_is_running() - Returns if a given DAMON context is running.
+ * @ctx:	The DAMON context to see if running.
+ *
+ * Return: true if @ctx is running, false otherwise.
+ */
+bool damon_is_running(struct damon_ctx *ctx)
 {
 	bool running;
 

index 1b1476b79cdb..79d65dcc9dd0 100644
@@ -1189,16 +1189,6 @@ static void damon_sysfs_kdamond_rm_dirs(struct damon_sysfs_kdamond *kdamond)
 	kobject_put(&kdamond->contexts->kobj);
 }
 
-static bool damon_sysfs_ctx_running(struct damon_ctx *ctx)
-{
-	bool running;
-
-	mutex_lock(&ctx->kdamond_lock);
-	running = ctx->kdamond != NULL;
-	mutex_unlock(&ctx->kdamond_lock);
-	return running;
-}
-
 /*
  * enum damon_sysfs_cmd - Commands for a specific kdamond.
  */

@@ -1275,7 +1265,7 @@ static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
 	if (!ctx)
 		running = false;
 	else
-		running = damon_sysfs_ctx_running(ctx);
+		running = damon_is_running(ctx);
 
 	return sysfs_emit(buf, "%s\n", running ?
 			damon_sysfs_cmd_strs[DAMON_SYSFS_CMD_ON] :

@@ -1429,7 +1419,7 @@ static inline bool damon_sysfs_kdamond_running(
 		struct damon_sysfs_kdamond *kdamond)
 {
 	return kdamond->damon_ctx &&
-		damon_sysfs_ctx_running(kdamond->damon_ctx);
+		damon_is_running(kdamond->damon_ctx);
 }
 
 static int damon_sysfs_apply_inputs(struct damon_ctx *ctx,

2.39.5

damon_sysfs_before_terminate() is a DAMON callback that is executed from the kdamond's context. Hence it is safe to access DAMON context internal data. But the function is unnecessarily holding kdamond_lock of the context. It is just unnecessary. Remove the locking code.

---
 mm/damon/sysfs.c | 2 --
 1 file changed, 2 deletions(-)

index 79d65dcc9dd0..c0193de6fb9a 100644
@@ -1387,12 +1387,10 @@ static void damon_sysfs_before_terminate(struct damon_ctx *ctx)
 	if (!damon_target_has_pid(ctx))
 		return;
 
-	mutex_lock(&ctx->kdamond_lock);
 	damon_for_each_target_safe(t, next, ctx) {
 		put_pid(t->pid);
 		damon_destroy_target(t);
 	}
-	mutex_unlock(&ctx->kdamond_lock);
 }
 
 /*

2.39.5

Recently a new mm tree for new patches, namely mm-new, has been added. Update DAMON maintainer's profile doc for DAMON patches life cycle, which depend on those of mm trees.

---
 Documentation/mm/damon/maintainer-profile.rst | 35 ++++++++++---------
 1 file changed, 19 insertions(+), 16 deletions(-)

index ce3e98458339..5cd07905a193 100644
@@ -7,9 +7,9 @@ The DAMON subsystem covers the files that are listed in 'DATA ACCESS MONITOR'
 section of 'MAINTAINERS' file.
 
 The mailing lists for the subsystem are [email protected] and
[email protected].  Patches should be made against the `mm-unstable tree
-<https://git.kernel.org/akpm/mm/h/mm-unstable>`_ whenever possible and posted
-to the mailing lists.
[email protected].  Patches should be made against the `mm-new tree
+<https://git.kernel.org/akpm/mm/h/mm-new>`_ whenever possible and posted to the
+mailing lists.
 
 SCM Trees
 ---------

@@ -17,17 +17,19 @@ SCM Trees
 There are multiple Linux trees for DAMON development.  Patches under
 development or testing are queued in `damon/next
 <https://git.kernel.org/sj/h/damon/next>`_ by the DAMON maintainer.
-Sufficiently reviewed patches will be queued in `mm-unstable
-<https://git.kernel.org/akpm/mm/h/mm-unstable>`_ by the memory management
-subsystem maintainer.  After more sufficient tests, the patches will be queued
-in `mm-stable <https://git.kernel.org/akpm/mm/h/mm-stable>`_, and finally
-pull-requested to the mainline by the memory management subsystem maintainer.
-
-Note again the patches for `mm-unstable tree
-<https://git.kernel.org/akpm/mm/h/mm-unstable>`_ are queued by the memory
-management subsystem maintainer.  If the patches requires some patches in
-`damon/next tree <https://git.kernel.org/sj/h/damon/next>`_ which not yet merged
-in mm-unstable, please make sure the requirement is clearly specified.
+Sufficiently reviewed patches will be queued in `mm-new
+<https://git.kernel.org/akpm/mm/h/mm-new>`_ by the memory management subsystem
+maintainer.  As more sufficient tests are done, the patches will move to
+`mm-unstable <https://git.kernel.org/akpm/mm/h/mm-unstable>`_ and then to
+`mm-stable <https://git.kernel.org/akpm/mm/h/mm-stable>`_.  And finally those
+will be pull-requested to the mainline by the memory management subsystem
+maintainer.
+
+Note again the patches for `mm-new tree
+<https://git.kernel.org/akpm/mm/h/mm-new>`_ are queued by the memory management
+subsystem maintainer.  If the patches requires some patches in `damon/next tree
+<https://git.kernel.org/sj/h/damon/next>`_ which not yet merged in mm-new,
+please make sure the requirement is clearly specified.
 
 Submit checklist addendum
 -------------------------

@@ -53,8 +55,9 @@ Further doing below and putting the results will be helpful.
 Key cycle dates
 ---------------
 
-Patches can be sent anytime.  Key cycle dates of the `mm-unstable
-<https://git.kernel.org/akpm/mm/h/mm-unstable>`_ and `mm-stable
+Patches can be sent anytime.  Key cycle dates of the `mm-new
+<https://git.kernel.org/akpm/mm/h/mm-new>`_, `mm-unstable
+<https://git.kernel.org/akpm/mm/h/mm-unstable>`_and `mm-stable
 <https://git.kernel.org/akpm/mm/h/mm-stable>`_ trees depend on the memory
 management subsystem maintainer.
 

2.39.5