Each DAMON operarions set is updating nr_accesses field of each
damon_region for each of their access check results, from the
check_accesses() callback. Directly accessing the field could make
things complex to manage and change in future. Define and use a
dedicated function for the purpose.
Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
---
include/linux/damon.h | 5 ++++-
mm/damon/core.c | 16 ++++++++++++++++
mm/damon/paddr.c | 6 ++----
mm/damon/vaddr.c | 6 ++----
4 files changed, 24 insertions(+), 9 deletions(-)
diff --git a/include/linux/damon.h b/include/linux/damon.h
index 9a32b8fd0bd3..17c504d236b9 100644
--- a/include/linux/damon.h
+++ b/include/linux/damon.h
@@ -45,7 +45,9 @@ struct damon_addr_range {
*
* @nr_accesses is reset to zero for every &damon_attrs->aggr_interval and be
* increased for every &damon_attrs->sample_interval if an access to the region
- * during the last sampling interval is found.
+ * during the last sampling interval is found. The update of this field should
+ * not be done with direct access but with the helper function,
+ * damon_update_region_access_rate().
*
* @age is initially zero, increased for each aggregation interval, and reset
* to zero again if the access frequency is significantly changed. If two
@@ -620,6 +622,7 @@ void damon_add_region(struct damon_region *r, struct damon_target *t);
void damon_destroy_region(struct damon_region *r, struct damon_target *t);
int damon_set_regions(struct damon_target *t, struct damon_addr_range *ranges,
unsigned int nr_ranges);
+void damon_update_region_access_rate(struct damon_region *r, bool accessed);
struct damos_filter *damos_new_filter(enum damos_filter_type type,
bool matching);
diff --git a/mm/damon/core.c b/mm/damon/core.c
index 6f37997afc54..3d51a1dfe104 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -1589,6 +1589,22 @@ int damon_set_region_biggest_system_ram_default(struct damon_target *t,
return damon_set_regions(t, &addr_range, 1);
}
+/**
+ * damon_update_region_access_rate() - Update the access rate of a region.
+ * @r: The DAMON region to update for its access check result.
+ * @accessed: Whether the region has accessed during last sampling interval.
+ *
+ * Update the access rate of a region with the region's last sampling interval
+ * access check result.
+ *
+ * Usually this will be called by &damon_operations->check_accesses callback.
+ */
+void damon_update_region_access_rate(struct damon_region *r, bool accessed)
+{
+ if (accessed)
+ r->nr_accesses++;
+}
+
static int __init damon_init(void)
{
damon_region_cache = KMEM_CACHE(damon_region, 0);
diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c
index 909db25efb35..44f21860b555 100644
--- a/mm/damon/paddr.c
+++ b/mm/damon/paddr.c
@@ -157,14 +157,12 @@ static void __damon_pa_check_access(struct damon_region *r)
/* If the region is in the last checked page, reuse the result */
if (ALIGN_DOWN(last_addr, last_folio_sz) ==
ALIGN_DOWN(r->sampling_addr, last_folio_sz)) {
- if (last_accessed)
- r->nr_accesses++;
+ damon_update_region_access_rate(r, last_accessed);
return;
}
last_accessed = damon_pa_young(r->sampling_addr, &last_folio_sz);
- if (last_accessed)
- r->nr_accesses++;
+ damon_update_region_access_rate(r, last_accessed);
last_addr = r->sampling_addr;
}
diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c
index 4c81a9dbd044..7fc0bda73b4c 100644
--- a/mm/damon/vaddr.c
+++ b/mm/damon/vaddr.c
@@ -566,14 +566,12 @@ static void __damon_va_check_access(struct mm_struct *mm,
/* If the region is in the last checked page, reuse the result */
if (same_target && (ALIGN_DOWN(last_addr, last_folio_sz) ==
ALIGN_DOWN(r->sampling_addr, last_folio_sz))) {
- if (last_accessed)
- r->nr_accesses++;
+ damon_update_region_access_rate(r, last_accessed);
return;
}
last_accessed = damon_va_young(mm, r->sampling_addr, &last_folio_sz);
- if (last_accessed)
- r->nr_accesses++;
+ damon_update_region_access_rate(r, last_accessed);
last_addr = r->sampling_addr;
}
--
2.25.1
