mm/damon/reclaim: cover all system rams

DAMON_RECLAIM allows users to set the physical address range to monitor
and do the work on.  When users don't explicitly set the range, the
biggest System RAM resource of the system is selected as the monitoring
target address range.  The intention was to reduce the overhead from
monitoring non-System RAM areas because monitoring of non-System RAM may
be meaningless.  However, because of the sampling based access check and
adaptive regions adjustment, the overhead should be negligible.  It makes
more sense to just cover all system rams of the system.  Do so.

Link: https://lore.kernel.org/20260429041232.90257-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c
index b330ff1695907404fde5764eaf73c2ca76f3a271..a60ee800d63e91a13f350032b3bc44db394a7b61 100644 (file)
--- a/mm/damon/reclaim.c
+++ b/mm/damon/reclaim.c
@@ -113,7 +113,8 @@ DEFINE_DAMON_MODULES_MON_ATTRS_PARAMS(damon_reclaim_mon_attrs);
  * Start of the target memory region in physical address.
  *
  * The start physical address of memory region that DAMON_RECLAIM will do work
- * against.  By default, biggest System RAM is used as the region.
+ * against.  By default, the system's entire physical memory is used as the
+ * region.
  */
 static unsigned long monitor_region_start __read_mostly;
 module_param(monitor_region_start, ulong, 0600);
@@ -122,7 +123,8 @@ module_param(monitor_region_start, ulong, 0600);
  * End of the target memory region in physical address.
  *
  * The end physical address of memory region that DAMON_RECLAIM will do work
- * against.  By default, biggest System RAM is used as the region.
+ * against.  By default, the system's entire physical memory is used as the
+ * region.
  */
 static unsigned long monitor_region_end __read_mostly;
 module_param(monitor_region_end, ulong, 0600);
@@ -232,11 +234,9 @@ static int damon_reclaim_apply_parameters(void)
                damos_add_filter(scheme, filter);
        }
 
-       err = damon_set_region_biggest_system_ram_default(param_target,
-                                       &monitor_region_start,
-                                       &monitor_region_end,
-                                       param_ctx->addr_unit,
-                                       param_ctx->min_region_sz);
+       err = damon_set_region_system_rams_default(param_target,
+                       &monitor_region_start, &monitor_region_end,
+                       param_ctx->addr_unit, param_ctx->min_region_sz);
        if (err)
                goto out;
        err = damon_commit_ctx(ctx, param_ctx);