[PATCH 4/5] mm/damon/reclaim: respect addr_unit on default monitoring region setup

From: SeongJae Park

Date: Wed Mar 11 2026 - 01:30:26 EST


In the past, damon_set_region_biggest_system_ram_default(), which is the
core function for setting the default monitoring target region of
DAMON_RECLAIM, didn't support addr_unit. Hence DAMON_RECLAIM was
silently ignoring the user input for addr_unit when the user doesn't
explicitly set the monitoring target regions, and therefore the default
target region is being used. No real problem from that ignorance was
reported so far. But, the implicit rule is only making things
confusing. Also, the default target region setup function is updated to
support addr_unit. Hence there is no reason to keep ignoring it.
Respect the user-passed addr_unit for the default target monitoring
region use case.

Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
---
mm/damon/reclaim.c | 6 ------
1 file changed, 6 deletions(-)

diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c
index 01f2f6cdbcdfe..86da147786583 100644
--- a/mm/damon/reclaim.c
+++ b/mm/damon/reclaim.c
@@ -201,12 +201,6 @@ static int damon_reclaim_apply_parameters(void)
if (err)
return err;

- /*
- * If monitor_region_start/end are unset, always silently
- * reset addr_unit to 1.
- */
- if (!monitor_region_start && !monitor_region_end)
- addr_unit = 1;
param_ctx->addr_unit = addr_unit;
param_ctx->min_region_sz = max(DAMON_MIN_REGION_SZ / addr_unit, 1);

--
2.47.3