mm/damon: rename DAMON_MIN_REGION to DAMON_MIN_REGION_SZ

[ Upstream commit dfb1b0c ]

The macro is for the default minimum size of each DAMON region.  There was
a case that a reader was confused if it is the minimum number of total
DAMON regions, which is set on damon_attrs->min_nr_regions.  Make the name
more explicit.

Link: https://lkml.kernel.org/r/20260117175256.82826-8-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Stable-dep-of: c80f46a ("mm/damon/core: disallow non-power of two min_region_sz")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: sjp38

include/linux/damon.h

@@ -15,7 +15,7 @@
 #include <linux/random.h>
 
 /* Minimal region size.  Every damon_region is aligned by this. */
-#define DAMON_MIN_REGION	PAGE_SIZE
+#define DAMON_MIN_REGION_SZ	PAGE_SIZE
 /* Max priority score for DAMON-based operation schemes */
 #define DAMOS_MAX_SCORE		(99)
 

mm/damon/core.c

@@ -546,7 +546,7 @@ struct damon_ctx *damon_new_ctx(void)
 	ctx->attrs.max_nr_regions = 1000;
 
 	ctx->addr_unit = 1;
-	ctx->min_sz_region = DAMON_MIN_REGION;
+	ctx->min_sz_region = DAMON_MIN_REGION_SZ;
 
 	INIT_LIST_HEAD(&ctx->adaptive_targets);
 	INIT_LIST_HEAD(&ctx->schemes);

mm/damon/lru_sort.c

@@ -212,7 +212,7 @@ static int damon_lru_sort_apply_parameters(void)
 	if (!monitor_region_start && !monitor_region_end)
 		addr_unit = 1;
 	param_ctx->addr_unit = addr_unit;
-	param_ctx->min_sz_region = max(DAMON_MIN_REGION / addr_unit, 1);
+	param_ctx->min_sz_region = max(DAMON_MIN_REGION_SZ / addr_unit, 1);
 
 	if (!damon_lru_sort_mon_attrs.sample_interval) {
 		err = -EINVAL;

mm/damon/reclaim.c

@@ -208,7 +208,7 @@ static int damon_reclaim_apply_parameters(void)
 	if (!monitor_region_start && !monitor_region_end)
 		addr_unit = 1;
 	param_ctx->addr_unit = addr_unit;
-	param_ctx->min_sz_region = max(DAMON_MIN_REGION / addr_unit, 1);
+	param_ctx->min_sz_region = max(DAMON_MIN_REGION_SZ / addr_unit, 1);
 
 	if (!damon_reclaim_mon_attrs.aggr_interval) {
 		err = -EINVAL;

mm/damon/sysfs.c

@@ -1470,7 +1470,7 @@ static int damon_sysfs_apply_inputs(struct damon_ctx *ctx,
 	/* addr_unit is respected by only DAMON_OPS_PADDR */
 	if (sys_ctx->ops_id == DAMON_OPS_PADDR)
 		ctx->min_sz_region = max(
-				DAMON_MIN_REGION / sys_ctx->addr_unit, 1);
+				DAMON_MIN_REGION_SZ / sys_ctx->addr_unit, 1);
 	err = damon_sysfs_set_attrs(ctx, sys_ctx->attrs);
 	if (err)
 		return err;

mm/damon/tests/vaddr-kunit.h

@@ -147,7 +147,7 @@ static void damon_do_test_apply_three_regions(struct kunit *test,
 		damon_add_region(r, t);
 	}
 
-	damon_set_regions(t, three_regions, 3, DAMON_MIN_REGION);
+	damon_set_regions(t, three_regions, 3, DAMON_MIN_REGION_SZ);
 
 	for (i = 0; i < nr_expected / 2; i++) {
 		r = __nth_region_of(t, i);

mm/damon/vaddr.c

@@ -19,8 +19,8 @@
 #include "ops-common.h"
 
 #ifdef CONFIG_DAMON_VADDR_KUNIT_TEST
-#undef DAMON_MIN_REGION
-#define DAMON_MIN_REGION 1
+#undef DAMON_MIN_REGION_SZ
+#define DAMON_MIN_REGION_SZ 1
 #endif
 
 /*
@@ -78,7 +78,7 @@ static int damon_va_evenly_split_region(struct damon_target *t,
 
 	orig_end = r->ar.end;
 	sz_orig = damon_sz_region(r);
-	sz_piece = ALIGN_DOWN(sz_orig / nr_pieces, DAMON_MIN_REGION);
+	sz_piece = ALIGN_DOWN(sz_orig / nr_pieces, DAMON_MIN_REGION_SZ);
 
 	if (!sz_piece)
 		return -EINVAL;
@@ -161,12 +161,12 @@ static int __damon_va_three_regions(struct mm_struct *mm,
 		swap(first_gap, second_gap);
 
 	/* Store the result */
-	regions[0].start = ALIGN(start, DAMON_MIN_REGION);
-	regions[0].end = ALIGN(first_gap.start, DAMON_MIN_REGION);
-	regions[1].start = ALIGN(first_gap.end, DAMON_MIN_REGION);
-	regions[1].end = ALIGN(second_gap.start, DAMON_MIN_REGION);
-	regions[2].start = ALIGN(second_gap.end, DAMON_MIN_REGION);
-	regions[2].end = ALIGN(prev->vm_end, DAMON_MIN_REGION);
+	regions[0].start = ALIGN(start, DAMON_MIN_REGION_SZ);
+	regions[0].end = ALIGN(first_gap.start, DAMON_MIN_REGION_SZ);
+	regions[1].start = ALIGN(first_gap.end, DAMON_MIN_REGION_SZ);
+	regions[1].end = ALIGN(second_gap.start, DAMON_MIN_REGION_SZ);
+	regions[2].start = ALIGN(second_gap.end, DAMON_MIN_REGION_SZ);
+	regions[2].end = ALIGN(prev->vm_end, DAMON_MIN_REGION_SZ);
 
 	return 0;
 }
@@ -259,8 +259,8 @@ static void __damon_va_init_regions(struct damon_ctx *ctx,
 		sz += regions[i].end - regions[i].start;
 	if (ctx->attrs.min_nr_regions)
 		sz /= ctx->attrs.min_nr_regions;
-	if (sz < DAMON_MIN_REGION)
-		sz = DAMON_MIN_REGION;
+	if (sz < DAMON_MIN_REGION_SZ)
+		sz = DAMON_MIN_REGION_SZ;
 
 	/* Set the initial three regions of the target */
 	for (i = 0; i < 3; i++) {
@@ -299,7 +299,7 @@ static void damon_va_update(struct damon_ctx *ctx)
 	damon_for_each_target(t, ctx) {
 		if (damon_va_three_regions(t, three_regions))
 			continue;
-		damon_set_regions(t, three_regions, 3, DAMON_MIN_REGION);
+		damon_set_regions(t, three_regions, 3, DAMON_MIN_REGION_SZ);
 	}
 }