mm/damon/reclaim: use 'struct damon_attrs' for storing parameters for it

DAMON_RECLAIM receives monitoring attributes by parameters one by one to
separate variables, and then combine those into 'struct damon_attrs'. 
This commit makes the module directly stores the parameter values to a
static 'struct damon_attrs' variable and use it to simplify the code.

Link: https://lkml.kernel.org/r/20220913174449.50645-8-sj@kernel.orgSigned-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/damon/reclaim.c

@@ -129,14 +129,22 @@ module_param(wmarks_mid, ulong, 0600);
 static unsigned long wmarks_low __read_mostly = 200;
 module_param(wmarks_low, ulong, 0600);
 
+static struct damon_attrs damon_reclaim_mon_attrs = {
+	.sample_interval = 5000,
+	.aggr_interval = 100000,
+	.ops_update_interval = 0,
+	.min_nr_regions = 10,
+	.max_nr_regions = 1000,
+};
+
 /*
  * Sampling interval for the monitoring in microseconds.
  *
  * The sampling interval of DAMON for the cold memory monitoring.  Please refer
  * to the DAMON documentation for more detail.  5 ms by default.
  */
-static unsigned long sample_interval __read_mostly = 5000;
-module_param(sample_interval, ulong, 0600);
+module_param_named(sample_interval, damon_reclaim_mon_attrs.sample_interval,
+		ulong, 0600);
 
 /*
  * Aggregation interval for the monitoring in microseconds.
@@ -144,8 +152,8 @@ module_param(sample_interval, ulong, 0600);
  * The aggregation interval of DAMON for the cold memory monitoring.  Please
  * refer to the DAMON documentation for more detail.  100 ms by default.
  */
-static unsigned long aggr_interval __read_mostly = 100000;
-module_param(aggr_interval, ulong, 0600);
+module_param_named(aggr_interval, damon_reclaim_mon_attrs.aggr_interval, ulong,
+		0600);
 
 /*
  * Minimum number of monitoring regions.
@@ -155,8 +163,8 @@ module_param(aggr_interval, ulong, 0600);
  * But, setting this too high could result in increased monitoring overhead.
  * Please refer to the DAMON documentation for more detail.  10 by default.
  */
-static unsigned long min_nr_regions __read_mostly = 10;
-module_param(min_nr_regions, ulong, 0600);
+module_param_named(min_nr_regions, damon_reclaim_mon_attrs.min_nr_regions,
+		ulong, 0600);
 
 /*
  * Maximum number of monitoring regions.
@@ -166,8 +174,8 @@ module_param(min_nr_regions, ulong, 0600);
  * However, setting this too low could result in bad monitoring quality.
  * Please refer to the DAMON documentation for more detail.  1000 by default.
  */
-static unsigned long max_nr_regions __read_mostly = 1000;
-module_param(max_nr_regions, ulong, 0600);
+module_param_named(max_nr_regions, damon_reclaim_mon_attrs.max_nr_regions,
+		ulong, 0600);
 
 /*
  * Start of the target memory region in physical address.
@@ -239,7 +247,8 @@ static struct damos *damon_reclaim_new_scheme(void)
 		.min_nr_accesses = 0,
 		.max_nr_accesses = 0,
 		/* for min_age or more micro-seconds */
-		.min_age_region = min_age / aggr_interval,
+		.min_age_region = min_age /
+			damon_reclaim_mon_attrs.aggr_interval,
 		.max_age_region = UINT_MAX,
 	};
 	struct damos_watermarks wmarks = {
@@ -275,18 +284,11 @@ static struct damos *damon_reclaim_new_scheme(void)
 
 static int damon_reclaim_apply_parameters(void)
 {
-	struct damon_attrs attrs = {
-		.sample_interval = sample_interval,
-		.aggr_interval = aggr_interval,
-		.ops_update_interval = 0,
-		.min_nr_regions = min_nr_regions,
-		.max_nr_regions = max_nr_regions,
-	};
 	struct damos *scheme;
 	struct damon_addr_range addr_range;
 	int err = 0;
 
-	err = damon_set_attrs(ctx, &attrs);
+	err = damon_set_attrs(ctx, &damon_reclaim_mon_attrs);
 	if (err)
 		return err;