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.
Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
---
mm/damon/sysfs-common.h | 6 ++++
mm/damon/sysfs-schemes.c | 75 ++++++++++++++++++++++++++++++++++++++++
mm/damon/sysfs.c | 57 ++++++++++++++++++++++++++++--
3 files changed, 136 insertions(+), 2 deletions(-)
diff --git a/mm/damon/sysfs-common.h b/mm/damon/sysfs-common.h
index 4626b2784404..634a6e7fca78 100644
--- a/mm/damon/sysfs-common.h
+++ b/mm/damon/sysfs-common.h
@@ -44,3 +44,9 @@ int damon_sysfs_set_schemes(struct damon_ctx *ctx,
void damon_sysfs_schemes_update_stats(
struct damon_sysfs_schemes *sysfs_schemes,
struct damon_ctx *ctx);
+
+int damon_sysfs_schemes_update_regions_start(
+ struct damon_sysfs_schemes *sysfs_schemes,
+ struct damon_ctx *ctx);
+
+int damon_sysfs_schemes_update_regions_stop(struct damon_ctx *ctx);
diff --git a/mm/damon/sysfs-schemes.c b/mm/damon/sysfs-schemes.c
index 1a8ab6341bf1..dd4ecd093cd6 100644
--- a/mm/damon/sysfs-schemes.c
+++ b/mm/damon/sysfs-schemes.c
@@ -1198,3 +1198,78 @@ void damon_sysfs_schemes_update_stats(
sysfs_stats->qt_exceeds = scheme->stat.qt_exceeds;
}
}
+
+/*
+ * damon_sysfs_schemes that need to update its schemes regions dir. Protected
+ * by damon_sysfs_lock
+ */
+static struct damon_sysfs_schemes *damon_sysfs_schemes_for_damos_callback;
+static int damon_sysfs_schemes_region_idx;
+
+/*
+ * DAMON callback that called before damos apply. While this callback is
+ * registered, damon_sysfs_lock should be held to ensure the regions
+ * directories exist.
+ */
+static int damon_sysfs_before_damos_apply(struct damon_ctx *ctx,
+ struct damon_target *t, struct damon_region *r,
+ struct damos *s)
+{
+ struct damos *scheme;
+ struct damon_sysfs_scheme_regions *sysfs_regions;
+ struct damon_sysfs_scheme_region *region;
+ struct damon_sysfs_schemes *sysfs_schemes =
+ damon_sysfs_schemes_for_damos_callback;
+ int schemes_idx = 0;
+
+ damon_for_each_scheme(scheme, ctx) {
+ if (scheme == s)
+ break;
+ schemes_idx++;
+ }
+ sysfs_regions = sysfs_schemes->schemes_arr[schemes_idx]->tried_regions;
+ region = damon_sysfs_scheme_region_alloc(r);
+ list_add_tail(®ion->list, &sysfs_regions->regions_list);
+ sysfs_regions->nr_regions++;
+ if (kobject_init_and_add(®ion->kobj,
+ &damon_sysfs_scheme_region_ktype,
+ &sysfs_regions->kobj, "%d",
+ damon_sysfs_schemes_region_idx++)) {
+ kobject_put(®ion->kobj);
+ }
+ return 0;
+}
+
+/* Called from damon_sysfs_cmd_request_callback under damon_sysfs_lock */
+int damon_sysfs_schemes_update_regions_start(
+ struct damon_sysfs_schemes *sysfs_schemes,
+ struct damon_ctx *ctx)
+{
+ struct damos *scheme;
+ int schemes_idx = 0;
+
+ damon_for_each_scheme(scheme, ctx) {
+ struct damon_sysfs_scheme *sysfs_scheme;
+
+ sysfs_scheme = sysfs_schemes->schemes_arr[schemes_idx++];
+ damon_sysfs_scheme_regions_rm_dirs(
+ sysfs_scheme->tried_regions);
+ }
+
+ damon_sysfs_schemes_for_damos_callback = sysfs_schemes;
+ ctx->callback.before_damos_apply = damon_sysfs_before_damos_apply;
+ return 0;
+}
+
+/*
+ * Called from damon_sysfs_cmd_request_callback under damon_sysfs_lock. Caller
+ * should unlock damon_sysfs_lock which held before
+ * damon_sysfs_schemes_update_regions_start()
+ */
+int damon_sysfs_schemes_update_regions_stop(struct damon_ctx *ctx)
+{
+ damon_sysfs_schemes_for_damos_callback = NULL;
+ ctx->callback.before_damos_apply = NULL;
+ damon_sysfs_schemes_region_idx = 0;
+ return 0;
+}
diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
index 284daf274b3e..ffb5a84059d7 100644
--- a/mm/damon/sysfs.c
+++ b/mm/damon/sysfs.c
@@ -999,6 +999,11 @@ enum damon_sysfs_cmd {
* files.
*/
DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS,
+ /*
+ * @DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS: Update schemes tried
+ * regions
+ */
+ DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS,
/*
* @NR_DAMON_SYSFS_CMDS: Total number of DAMON sysfs commands.
*/
@@ -1011,6 +1016,7 @@ static const char * const damon_sysfs_cmd_strs[] = {
"off",
"commit",
"update_schemes_stats",
+ "update_schemes_tried_regions",
};
/*
@@ -1193,6 +1199,16 @@ static int damon_sysfs_set_targets(struct damon_ctx *ctx,
static void damon_sysfs_before_terminate(struct damon_ctx *ctx)
{
struct damon_target *t, *next;
+ struct damon_sysfs_kdamond *kdamond;
+
+ /* damon_sysfs_schemes_update_regions_stop() might not yet called */
+ kdamond = damon_sysfs_cmd_request.kdamond;
+ if (kdamond && damon_sysfs_cmd_request.cmd ==
+ DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS &&
+ ctx == kdamond->damon_ctx) {
+ damon_sysfs_schemes_update_regions_stop(ctx);
+ mutex_unlock(&damon_sysfs_lock);
+ }
if (!damon_target_has_pid(ctx))
return;
@@ -1225,6 +1241,27 @@ static int damon_sysfs_upd_schemes_stats(struct damon_sysfs_kdamond *kdamond)
return 0;
}
+static int damon_sysfs_upd_schemes_regions_start(
+ struct damon_sysfs_kdamond *kdamond)
+{
+ struct damon_ctx *ctx = kdamond->damon_ctx;
+
+ if (!ctx)
+ return -EINVAL;
+ return damon_sysfs_schemes_update_regions_start(
+ kdamond->contexts->contexts_arr[0]->schemes, ctx);
+}
+
+static int damon_sysfs_upd_schemes_regions_stop(
+ struct damon_sysfs_kdamond *kdamond)
+{
+ struct damon_ctx *ctx = kdamond->damon_ctx;
+
+ if (!ctx)
+ return -EINVAL;
+ return damon_sysfs_schemes_update_regions_stop(ctx);
+}
+
static inline bool damon_sysfs_kdamond_running(
struct damon_sysfs_kdamond *kdamond)
{
@@ -1277,10 +1314,12 @@ static int damon_sysfs_commit_input(struct damon_sysfs_kdamond *kdamond)
static int damon_sysfs_cmd_request_callback(struct damon_ctx *c)
{
struct damon_sysfs_kdamond *kdamond;
+ static bool damon_sysfs_schemes_regions_updating;
int err = 0;
/* avoid deadlock due to concurrent state_store('off') */
- if (!mutex_trylock(&damon_sysfs_lock))
+ if (!damon_sysfs_schemes_regions_updating &&
+ !mutex_trylock(&damon_sysfs_lock))
return 0;
kdamond = damon_sysfs_cmd_request.kdamond;
if (!kdamond || kdamond->damon_ctx != c)
@@ -1292,13 +1331,27 @@ static int damon_sysfs_cmd_request_callback(struct damon_ctx *c)
case DAMON_SYSFS_CMD_COMMIT:
err = damon_sysfs_commit_input(kdamond);
break;
+ case DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS:
+ if (!damon_sysfs_schemes_regions_updating) {
+ err = damon_sysfs_upd_schemes_regions_start(kdamond);
+ if (!err) {
+ damon_sysfs_schemes_regions_updating = true;
+ goto keep_lock_out;
+ }
+ } else {
+ err = damon_sysfs_upd_schemes_regions_stop(kdamond);
+ damon_sysfs_schemes_regions_updating = false;
+ }
+ break;
default:
break;
}
/* Mark the request as invalid now. */
damon_sysfs_cmd_request.kdamond = NULL;
out:
- mutex_unlock(&damon_sysfs_lock);
+ if (!damon_sysfs_schemes_regions_updating)
+ mutex_unlock(&damon_sysfs_lock);
+keep_lock_out:
return err;
}
--
2.25.1
