[RFC PATCH v3 3/7] mm/damon/sysfs-schemes: add target_nid on sysfs-schemes

Honggyu Kim
2024-04-05T06:09:14Z

From: Hyeongtak Ji <hyeongtak.ji@sk.com>

This patch adds target_nid under
/sys/kernel/mm/damon/admin/kdamonds/<N>/contexts/<N>/schemes/<N>/

The 'target_nid' can be used as the destination node for DAMOS actions
such as DAMOS_MIGRATE_{HOT,COLD} in the follow up patches.

Signed-off-by: Hyeongtak Ji <hyeongtak.ji@sk.com>
Signed-off-by: Honggyu Kim <honggyu.kim@sk.com>
---
include/linux/damon.h | 11 ++++++++++-
mm/damon/core.c | 5 ++++-
mm/damon/dbgfs.c | 2 +-
mm/damon/lru_sort.c | 3 ++-
mm/damon/reclaim.c | 3 ++-
mm/damon/sysfs-schemes.c | 33 ++++++++++++++++++++++++++++++++-
6 files changed, 51 insertions(+), 6 deletions(-)

diff --git a/include/linux/damon.h b/include/linux/damon.h
index 5881e4ac30be..24ea33a03d5d 100644
--- a/include/linux/damon.h
+++ b/include/linux/damon.h
@@ -337,6 +337,7 @@ struct damos_access_pattern {
* @apply_interval_us: The time between applying the @action.
* @quota: Control the aggressiveness of this scheme.
* @wmarks: Watermarks for automated (in)activation of this scheme.
+ * @target_nid: Destination node if @action is "migrate_{hot,cold}".
* @filters: Additional set of &struct damos_filter for &action.
* @stat: Statistics of this scheme.
* @list: List head for siblings.
@@ -352,6 +353,10 @@ struct damos_access_pattern {
* monitoring context are inactive, DAMON stops monitoring either, and just
* repeatedly checks the watermarks.
*
+ * @target_nid is used to set the migration target node for migrate_hot or
+ * migrate_cold actions, which means it's only meaningful when @action is either
+ * "migrate_hot" or "migrate_cold".
+ *
* Before applying the &action to a memory region, &struct damon_operations
* implementation could check pages of the region and skip &action to respect
* &filters
@@ -373,6 +378,9 @@ struct damos {
/* public: */
struct damos_quota quota;
struct damos_watermarks wmarks;
+ union {
+ int target_nid;
+ };
struct list_head filters;
struct damos_stat stat;
struct list_head list;
@@ -677,7 +685,8 @@ struct damos *damon_new_scheme(struct damos_access_pattern *pattern,
enum damos_action action,
unsigned long apply_interval_us,
struct damos_quota *quota,
- struct damos_watermarks *wmarks);
+ struct damos_watermarks *wmarks,
+ int target_nid);
void damon_add_scheme(struct damon_ctx *ctx, struct damos *s);
void damon_destroy_scheme(struct damos *s);

diff --git a/mm/damon/core.c b/mm/damon/core.c
index 5b325749fc12..7ff0259d9fa6 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -316,7 +316,8 @@ struct damos *damon_new_scheme(struct damos_access_pattern *pattern,
enum damos_action action,
unsigned long apply_interval_us,
struct damos_quota *quota,
- struct damos_watermarks *wmarks)
+ struct damos_watermarks *wmarks,
+ int target_nid)
{
struct damos *scheme;

@@ -341,6 +342,8 @@ struct damos *damon_new_scheme(struct damos_access_pattern *pattern,
scheme->wmarks = *wmarks;
scheme->wmarks.activated = true;

+ scheme->target_nid = target_nid;
+
return scheme;
}

diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c
index 7dac24e69e3b..d04fdccfa65b 100644
--- a/mm/damon/dbgfs.c
+++ b/mm/damon/dbgfs.c
@@ -279,7 +279,7 @@ static struct damos **str_to_schemes(const char *str, ssize_t len,

pos += parsed;
scheme = damon_new_scheme(&pattern, action, 0, &quota,
- &wmarks);
+ &wmarks, NUMA_NO_NODE);
if (!scheme)
goto fail;

diff --git a/mm/damon/lru_sort.c b/mm/damon/lru_sort.c
index 3de2916a65c3..3775f0f2743d 100644
--- a/mm/damon/lru_sort.c
+++ b/mm/damon/lru_sort.c
@@ -163,7 +163,8 @@ static struct damos *damon_lru_sort_new_scheme(
/* under the quota. */
&quota,
/* (De)activate this according to the watermarks. */
- &damon_lru_sort_wmarks);
+ &damon_lru_sort_wmarks,
+ NUMA_NO_NODE);
}

/* Create a DAMON-based operation scheme for hot memory regions */
diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c
index 66e190f0374a..84e6e96b5dcc 100644
--- a/mm/damon/reclaim.c
+++ b/mm/damon/reclaim.c
@@ -147,7 +147,8 @@ static struct damos *damon_reclaim_new_scheme(void)
/* under the quota. */
&damon_reclaim_quota,
/* (De)activate this according to the watermarks. */
- &damon_reclaim_wmarks);
+ &damon_reclaim_wmarks,
+ NUMA_NO_NODE);
}

static void damon_reclaim_copy_quota_status(struct damos_quota *dst,
diff --git a/mm/damon/sysfs-schemes.c b/mm/damon/sysfs-schemes.c
index ae0f0b314f3a..1a30ea82c890 100644
--- a/mm/damon/sysfs-schemes.c
+++ b/mm/damon/sysfs-schemes.c
@@ -6,6 +6,7 @@
*/

#include <linux/slab.h>
+#include <linux/numa.h>

#include "sysfs-common.h"

@@ -1393,6 +1394,7 @@ struct damon_sysfs_scheme {
struct damon_sysfs_scheme_filters *filters;
struct damon_sysfs_stats *stats;
struct damon_sysfs_scheme_regions *tried_regions;
+ int target_nid;
};

/* This should match with enum damos_action */
@@ -1418,6 +1420,7 @@ static struct damon_sysfs_scheme *damon_sysfs_scheme_alloc(
scheme->kobj = (struct kobject){};
scheme->action = action;
scheme->apply_interval_us = apply_interval_us;
+ scheme->target_nid = NUMA_NO_NODE;
return scheme;
}

@@ -1640,6 +1643,28 @@ static ssize_t apply_interval_us_store(struct kobject *kobj,
return err ? err : count;
}

+static ssize_t target_nid_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ struct damon_sysfs_scheme *scheme = container_of(kobj,
+ struct damon_sysfs_scheme, kobj);
+
+ return sysfs_emit(buf, "%d\n", scheme->target_nid);
+}
+
+static ssize_t target_nid_store(struct kobject *kobj,
+ struct kobj_attribute *attr, const char *buf, size_t count)
+{
+ struct damon_sysfs_scheme *scheme = container_of(kobj,
+ struct damon_sysfs_scheme, kobj);
+ int err = 0;
+
+ /* TODO: error handling for target_nid range. */
+ err = kstrtoint(buf, 0, &scheme->target_nid);
+
+ return err ? err : count;
+}
+
static void damon_sysfs_scheme_release(struct kobject *kobj)
{
kfree(container_of(kobj, struct damon_sysfs_scheme, kobj));
@@ -1651,9 +1676,13 @@ static struct kobj_attribute damon_sysfs_scheme_action_attr =
static struct kobj_attribute damon_sysfs_scheme_apply_interval_us_attr =
__ATTR_RW_MODE(apply_interval_us, 0600);

+static struct kobj_attribute damon_sysfs_scheme_target_nid_attr =
+ __ATTR_RW_MODE(target_nid, 0600);
+
static struct attribute *damon_sysfs_scheme_attrs[] = {
&damon_sysfs_scheme_action_attr.attr,
&damon_sysfs_scheme_apply_interval_us_attr.attr,
+ &damon_sysfs_scheme_target_nid_attr.attr,
NULL,
};
ATTRIBUTE_GROUPS(damon_sysfs_scheme);
@@ -1956,7 +1985,8 @@ static struct damos *damon_sysfs_mk_scheme(
damos_sysfs_set_quota_score(sysfs_quotas->goals, &quota);

scheme = damon_new_scheme(&pattern, sysfs_scheme->action,
- sysfs_scheme->apply_interval_us, &quota, &wmarks);
+ sysfs_scheme->apply_interval_us, &quota, &wmarks,
+ sysfs_scheme->target_nid);
if (!scheme)
return NULL;

@@ -1987,6 +2017,7 @@ static void damon_sysfs_update_scheme(struct damos *scheme,

scheme->action = sysfs_scheme->action;
scheme->apply_interval_us = sysfs_scheme->apply_interval_us;
+ scheme->target_nid = sysfs_scheme->target_nid;

scheme->quota.ms = sysfs_quotas->ms;
scheme->quota.sz = sysfs_quotas->sz;
--
2.34.1