[linux.git] / mm / damon / reclaim.c

// SPDX-License-Identifier: GPL-2.0
/*
 * DAMON-based page reclamation
 *
 * Author: SeongJae Park <[email protected]>
 */

#define pr_fmt(fmt) "damon-reclaim: " fmt

#include <linux/damon.h>
#include <linux/kstrtox.h>
#include <linux/module.h>

#include "modules-common.h"

#ifdef MODULE_PARAM_PREFIX
#undef MODULE_PARAM_PREFIX
#endif
#define MODULE_PARAM_PREFIX "damon_reclaim."

/*
 * Enable or disable DAMON_RECLAIM.
 *
 * You can enable DAMON_RCLAIM by setting the value of this parameter as ``Y``.
 * Setting it as ``N`` disables DAMON_RECLAIM.  Note that DAMON_RECLAIM could
 * do no real monitoring and reclamation due to the watermarks-based activation
 * condition.  Refer to below descriptions for the watermarks parameter for
 * this.
 */
static bool enabled __read_mostly;

/*
 * Make DAMON_RECLAIM reads the input parameters again, except ``enabled``.
 *
 * Input parameters that updated while DAMON_RECLAIM is running are not applied
 * by default.  Once this parameter is set as ``Y``, DAMON_RECLAIM reads values
 * of parametrs except ``enabled`` again.  Once the re-reading is done, this
 * parameter is set as ``N``.  If invalid parameters are found while the
 * re-reading, DAMON_RECLAIM will be disabled.
 */
static bool commit_inputs __read_mostly;
module_param(commit_inputs, bool, 0600);

/*
 * Time threshold for cold memory regions identification in microseconds.
 *
 * If a memory region is not accessed for this or longer time, DAMON_RECLAIM
 * identifies the region as cold, and reclaims.  120 seconds by default.
 */
static unsigned long min_age __read_mostly = 120000000;
module_param(min_age, ulong, 0600);

static struct damos_quota damon_reclaim_quota = {
	/* use up to 10 ms time, reclaim up to 128 MiB per 1 sec by default */
	.ms = 10,
	.sz = 128 * 1024 * 1024,
	.reset_interval = 1000,
	/* Within the quota, page out older regions first. */
	.weight_sz = 0,
	.weight_nr_accesses = 0,
	.weight_age = 1
};
DEFINE_DAMON_MODULES_DAMOS_QUOTAS(damon_reclaim_quota);

/*
 * Desired level of memory pressure-stall time in microseconds.
 *
 * While keeping the caps that set by other quotas, DAMON_RECLAIM automatically
 * increases and decreases the effective level of the quota aiming this level of
 * memory pressure is incurred.  System-wide ``some`` memory PSI in microseconds
 * per quota reset interval (``quota_reset_interval_ms``) is collected and
 * compared to this value to see if the aim is satisfied.  Value zero means
 * disabling this auto-tuning feature.
 *
 * Disabled by default.
 */
static unsigned long quota_mem_pressure_us __read_mostly;
module_param(quota_mem_pressure_us, ulong, 0600);

/*
 * User-specifiable feedback for auto-tuning of the effective quota.
 *
 * While keeping the caps that set by other quotas, DAMON_RECLAIM automatically
 * increases and decreases the effective level of the quota aiming receiving this
 * feedback of value ``10,000`` from the user.  DAMON_RECLAIM assumes the feedback
 * value and the quota are positively proportional.  Value zero means disabling
 * this auto-tuning feature.
 *
 * Disabled by default.
 *
 */
static unsigned long quota_autotune_feedback __read_mostly;
module_param(quota_autotune_feedback, ulong, 0600);

static struct damos_watermarks damon_reclaim_wmarks = {
	.metric = DAMOS_WMARK_FREE_MEM_RATE,
	.interval = 5000000,	/* 5 seconds */
	.high = 500,		/* 50 percent */
	.mid = 400,		/* 40 percent */
	.low = 200,		/* 20 percent */
};
DEFINE_DAMON_MODULES_WMARKS_PARAMS(damon_reclaim_wmarks);

static struct damon_attrs damon_reclaim_mon_attrs = {
	.sample_interval = 5000,	/* 5 ms */
	.aggr_interval = 100000,	/* 100 ms */
	.ops_update_interval = 0,
	.min_nr_regions = 10,
	.max_nr_regions = 1000,
};
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.
 */
static unsigned long monitor_region_start __read_mostly;
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.
 */
static unsigned long monitor_region_end __read_mostly;
module_param(monitor_region_end, ulong, 0600);

/*
 * Skip anonymous pages reclamation.
 *
 * If this parameter is set as ``Y``, DAMON_RECLAIM does not reclaim anonymous
 * pages.  By default, ``N``.
 */
static bool skip_anon __read_mostly;
module_param(skip_anon, bool, 0600);

/*
 * PID of the DAMON thread
 *
 * If DAMON_RECLAIM is enabled, this becomes the PID of the worker thread.
 * Else, -1.
 */
static int kdamond_pid __read_mostly = -1;
module_param(kdamond_pid, int, 0400);

static struct damos_stat damon_reclaim_stat;
DEFINE_DAMON_MODULES_DAMOS_STATS_PARAMS(damon_reclaim_stat,
		reclaim_tried_regions, reclaimed_regions, quota_exceeds);

static struct damon_ctx *ctx;
static struct damon_target *target;

static struct damos *damon_reclaim_new_scheme(void)
{
	struct damos_access_pattern pattern = {
		/* Find regions having PAGE_SIZE or larger size */
		.min_sz_region = PAGE_SIZE,
		.max_sz_region = ULONG_MAX,
		/* and not accessed at all */
		.min_nr_accesses = 0,
		.max_nr_accesses = 0,
		/* for min_age or more micro-seconds */
		.min_age_region = min_age /
			damon_reclaim_mon_attrs.aggr_interval,
		.max_age_region = UINT_MAX,
	};

	return damon_new_scheme(
			&pattern,
			/* page out those, as soon as found */
			DAMOS_PAGEOUT,
			/* for each aggregation interval */
			0,
			/* under the quota. */
			&damon_reclaim_quota,
			/* (De)activate this according to the watermarks. */
			&damon_reclaim_wmarks,
			NUMA_NO_NODE);
}

static int damon_reclaim_apply_parameters(void)
{
	struct damon_ctx *param_ctx;
	struct damon_target *param_target;
	struct damos *scheme;
	struct damos_quota_goal *goal;
	struct damos_filter *filter;
	int err;

	err = damon_modules_new_paddr_ctx_target(&param_ctx, &param_target);
	if (err)
		return err;

	err = damon_set_attrs(ctx, &damon_reclaim_mon_attrs);
	if (err)
		goto out;

	err = -ENOMEM;
	scheme = damon_reclaim_new_scheme();
	if (!scheme)
		goto out;
	damon_set_schemes(ctx, &scheme, 1);

	if (quota_mem_pressure_us) {
		goal = damos_new_quota_goal(DAMOS_QUOTA_SOME_MEM_PSI_US,
				quota_mem_pressure_us);
		if (!goal)
			goto out;
		damos_add_quota_goal(&scheme->quota, goal);
	}

	if (quota_autotune_feedback) {
		goal = damos_new_quota_goal(DAMOS_QUOTA_USER_INPUT, 10000);
		if (!goal)
			goto out;
		goal->current_value = quota_autotune_feedback;
		damos_add_quota_goal(&scheme->quota, goal);
	}

	if (skip_anon) {
		filter = damos_new_filter(DAMOS_FILTER_TYPE_ANON, true);
		if (!filter)
			goto out;
		damos_add_filter(scheme, filter);
	}

	err = damon_set_region_biggest_system_ram_default(param_target,
					&monitor_region_start,
					&monitor_region_end);
	if (err)
		goto out;
	err = damon_commit_ctx(ctx, param_ctx);
out:
	damon_destroy_ctx(param_ctx);
	return err;
}

static int damon_reclaim_turn(bool on)
{
	int err;

	if (!on) {
		err = damon_stop(&ctx, 1);
		if (!err)
			kdamond_pid = -1;
		return err;
	}

	err = damon_reclaim_apply_parameters();
	if (err)
		return err;

	err = damon_start(&ctx, 1, true);
	if (err)
		return err;
	kdamond_pid = ctx->kdamond->pid;
	return 0;
}

static int damon_reclaim_enabled_store(const char *val,
		const struct kernel_param *kp)
{
	bool is_enabled = enabled;
	bool enable;
	int err;

	err = kstrtobool(val, &enable);
	if (err)
		return err;

	if (is_enabled == enable)
		return 0;

	/* Called before init function.  The function will handle this. */
	if (!ctx)
		goto set_param_out;

	err = damon_reclaim_turn(enable);
	if (err)
		return err;

set_param_out:
	enabled = enable;
	return err;
}

static const struct kernel_param_ops enabled_param_ops = {
	.set = damon_reclaim_enabled_store,
	.get = param_get_bool,
};

module_param_cb(enabled, &enabled_param_ops, &enabled, 0600);
MODULE_PARM_DESC(enabled,
	"Enable or disable DAMON_RECLAIM (default: disabled)");

static int damon_reclaim_handle_commit_inputs(void)
{
	int err;

	if (!commit_inputs)
		return 0;

	err = damon_reclaim_apply_parameters();
	commit_inputs = false;
	return err;
}

static int damon_reclaim_after_aggregation(struct damon_ctx *c)
{
	struct damos *s;

	/* update the stats parameter */
	damon_for_each_scheme(s, c)
		damon_reclaim_stat = s->stat;

	return damon_reclaim_handle_commit_inputs();
}

static int damon_reclaim_after_wmarks_check(struct damon_ctx *c)
{
	return damon_reclaim_handle_commit_inputs();
}

static int __init damon_reclaim_init(void)
{
	int err = damon_modules_new_paddr_ctx_target(&ctx, &target);

	if (err)
		return err;

	ctx->callback.after_wmarks_check = damon_reclaim_after_wmarks_check;
	ctx->callback.after_aggregation = damon_reclaim_after_aggregation;

	/* 'enabled' has set before this function, probably via command line */
	if (enabled)
		err = damon_reclaim_turn(true);

	return err;
}

module_init(damon_reclaim_init);
Commit	Line	Data
43b0536c SP	1	// SPDX-License-Identifier: GPL-2.0
	2	/*
	3	* DAMON-based page reclamation
	4	*
	5	* Author: SeongJae Park <[email protected]>
	6	*/
	7
	8	#define pr_fmt(fmt) "damon-reclaim: " fmt
	9
	10	#include <linux/damon.h>
e6aff38b	11	#include <linux/kstrtox.h>
43b0536c	12	#include <linux/module.h>
43b0536c	13
fdfc119c SP	14	#include "modules-common.h"
fdfc119c SP	15
43b0536c SP	16	#ifdef MODULE_PARAM_PREFIX
	17	#undef MODULE_PARAM_PREFIX
	18	#endif
	19	#define MODULE_PARAM_PREFIX "damon_reclaim."
	20
	21	/*
	22	* Enable or disable DAMON_RECLAIM.
	23	*
	24	* You can enable DAMON_RCLAIM by setting the value of this parameter as ``Y``.
	25	* Setting it as ``N`` disables DAMON_RECLAIM. Note that DAMON_RECLAIM could
	26	* do no real monitoring and reclamation due to the watermarks-based activation
	27	* condition. Refer to below descriptions for the watermarks parameter for
	28	* this.
	29	*/
	30	static bool enabled __read_mostly;
43b0536c	31
e035c280 SP	32	/*
	33	* Make DAMON_RECLAIM reads the input parameters again, except ``enabled``.
	34	*
	35	* Input parameters that updated while DAMON_RECLAIM is running are not applied
	36	* by default. Once this parameter is set as ``Y``, DAMON_RECLAIM reads values
	37	* of parametrs except ``enabled`` again. Once the re-reading is done, this
	38	* parameter is set as ``N``. If invalid parameters are found while the
	39	* re-reading, DAMON_RECLAIM will be disabled.
	40	*/
	41	static bool commit_inputs __read_mostly;
	42	module_param(commit_inputs, bool, 0600);
	43
43b0536c SP	44	/*
	45	* Time threshold for cold memory regions identification in microseconds.
	46	*
	47	* If a memory region is not accessed for this or longer time, DAMON_RECLAIM
	48	* identifies the region as cold, and reclaims. 120 seconds by default.
	49	*/
	50	static unsigned long min_age __read_mostly = 120000000;
	51	module_param(min_age, ulong, 0600);
	52
a9d57c73 SP	53	static struct damos_quota damon_reclaim_quota = {
	54	/* use up to 10 ms time, reclaim up to 128 MiB per 1 sec by default */
	55	.ms = 10,
	56	.sz = 128 * 1024 * 1024,
	57	.reset_interval = 1000,
	58	/* Within the quota, page out older regions first. */
	59	.weight_sz = 0,
	60	.weight_nr_accesses = 0,
	61	.weight_age = 1
	62	};
	63	DEFINE_DAMON_MODULES_DAMOS_QUOTAS(damon_reclaim_quota);
43b0536c	64
7ce55f8f SP	65	/*
	66	* Desired level of memory pressure-stall time in microseconds.
	67	*
	68	* While keeping the caps that set by other quotas, DAMON_RECLAIM automatically
	69	* increases and decreases the effective level of the quota aiming this level of
	70	* memory pressure is incurred. System-wide ``some`` memory PSI in microseconds
	71	* per quota reset interval (``quota_reset_interval_ms``) is collected and
	72	* compared to this value to see if the aim is satisfied. Value zero means
	73	* disabling this auto-tuning feature.
	74	*
	75	* Disabled by default.
	76	*/
	77	static unsigned long quota_mem_pressure_us __read_mostly;
	78	module_param(quota_mem_pressure_us, ulong, 0600);
	79
58dea17d SP	80	/*
	81	* User-specifiable feedback for auto-tuning of the effective quota.
	82	*
	83	* While keeping the caps that set by other quotas, DAMON_RECLAIM automatically
	84	* increases and decreases the effective level of the quota aiming receiving this
	85	* feedback of value ``10,000`` from the user. DAMON_RECLAIM assumes the feedback
	86	* value and the quota are positively proportional. Value zero means disabling
	87	* this auto-tuning feature.
	88	*
	89	* Disabled by default.
	90	*
	91	*/
	92	static unsigned long quota_autotune_feedback __read_mostly;
	93	module_param(quota_autotune_feedback, ulong, 0600);
	94
81f8f57f	95	static struct damos_watermarks damon_reclaim_wmarks = {
34f47ea6 SP	96	.metric = DAMOS_WMARK_FREE_MEM_RATE,
	97	.interval = 5000000, /* 5 seconds */
	98	.high = 500, /* 50 percent */
	99	.mid = 400, /* 40 percent */
	100	.low = 200, /* 20 percent */
	101	};
	102	DEFINE_DAMON_MODULES_WMARKS_PARAMS(damon_reclaim_wmarks);
43b0536c	103
8c341ae3	104	static struct damon_attrs damon_reclaim_mon_attrs = {
fdfc119c SP	105	.sample_interval = 5000, /* 5 ms */
fdfc119c SP	106	.aggr_interval = 100000, /* 100 ms */
8c341ae3 SP	107	.ops_update_interval = 0,
	108	.min_nr_regions = 10,
	109	.max_nr_regions = 1000,
	110	};
fdfc119c	111	DEFINE_DAMON_MODULES_MON_ATTRS_PARAMS(damon_reclaim_mon_attrs);
43b0536c SP	112
	113	/*
	114	* Start of the target memory region in physical address.
	115	*
	116	* The start physical address of memory region that DAMON_RECLAIM will do work
	117	* against. By default, biggest System RAM is used as the region.
	118	*/
	119	static unsigned long monitor_region_start __read_mostly;
	120	module_param(monitor_region_start, ulong, 0600);
	121
	122	/*
	123	* End of the target memory region in physical address.
	124	*
	125	* The end physical address of memory region that DAMON_RECLAIM will do work
	126	* against. By default, biggest System RAM is used as the region.
	127	*/
	128	static unsigned long monitor_region_end __read_mostly;
	129	module_param(monitor_region_end, ulong, 0600);
	130
66d9faec SP	131	/*
	132	* Skip anonymous pages reclamation.
	133	*
	134	* If this parameter is set as ``Y``, DAMON_RECLAIM does not reclaim anonymous
	135	* pages. By default, ``N``.
	136	*/
	137	static bool skip_anon __read_mostly;
	138	module_param(skip_anon, bool, 0600);
	139
43b0536c SP	140	/*
	141	* PID of the DAMON thread
	142	*
	143	* If DAMON_RECLAIM is enabled, this becomes the PID of the worker thread.
	144	* Else, -1.
	145	*/
	146	static int kdamond_pid __read_mostly = -1;
	147	module_param(kdamond_pid, int, 0400);
	148
b71f3ea8 SP	149	static struct damos_stat damon_reclaim_stat;
	150	DEFINE_DAMON_MODULES_DAMOS_STATS_PARAMS(damon_reclaim_stat,
	151	reclaim_tried_regions, reclaimed_regions, quota_exceeds);
60e52e7c	152
43b0536c SP	153	static struct damon_ctx *ctx;
	154	static struct damon_target *target;
	155
43b0536c SP	156	static struct damos *damon_reclaim_new_scheme(void)
43b0536c SP	157	{
f5a79d7c YD	158	struct damos_access_pattern pattern = {
	159	/* Find regions having PAGE_SIZE or larger size */
	160	.min_sz_region = PAGE_SIZE,
	161	.max_sz_region = ULONG_MAX,
	162	/* and not accessed at all */
	163	.min_nr_accesses = 0,
	164	.max_nr_accesses = 0,
	165	/* for min_age or more micro-seconds */
8c341ae3 SP	166	.min_age_region = min_age /
8c341ae3 SP	167	damon_reclaim_mon_attrs.aggr_interval,
f5a79d7c YD	168	.max_age_region = UINT_MAX,
f5a79d7c YD	169	};
f5a79d7c YD	170
	171	return damon_new_scheme(
	172	&pattern,
43b0536c SP	173	/* page out those, as soon as found */
43b0536c SP	174	DAMOS_PAGEOUT,
42f994b7 SP	175	/* for each aggregation interval */
42f994b7 SP	176	0,
43b0536c	177	/* under the quota. */
a9d57c73	178	&damon_reclaim_quota,
43b0536c	179	/* (De)activate this according to the watermarks. */
e36287c6 HJ	180	&damon_reclaim_wmarks,
e36287c6 HJ	181	NUMA_NO_NODE);
43b0536c SP	182	}
43b0536c SP	183
e035c280	184	static int damon_reclaim_apply_parameters(void)
43b0536c	185	{
11ddcfc2 SP	186	struct damon_ctx *param_ctx;
11ddcfc2 SP	187	struct damon_target *param_target;
b94322b1	188	struct damos *scheme;
58dea17d	189	struct damos_quota_goal *goal;
66d9faec	190	struct damos_filter *filter;
11ddcfc2	191	int err;
43b0536c	192
11ddcfc2	193	err = damon_modules_new_paddr_ctx_target(&param_ctx, &param_target);
43b0536c SP	194	if (err)
	195	return err;
	196
11ddcfc2 SP	197	err = damon_set_attrs(ctx, &damon_reclaim_mon_attrs);
	198	if (err)
	199	goto out;
	200
	201	err = -ENOMEM;
e035c280 SP	202	scheme = damon_reclaim_new_scheme();
e035c280 SP	203	if (!scheme)
11ddcfc2	204	goto out;
11ddcfc2	205	damon_set_schemes(ctx, &scheme, 1);
58dea17d	206
7ce55f8f SP	207	if (quota_mem_pressure_us) {
	208	goal = damos_new_quota_goal(DAMOS_QUOTA_SOME_MEM_PSI_US,
	209	quota_mem_pressure_us);
11ddcfc2 SP	210	if (!goal)
11ddcfc2 SP	211	goto out;
7ce55f8f SP	212	damos_add_quota_goal(&scheme->quota, goal);
	213	}
	214
58dea17d SP	215	if (quota_autotune_feedback) {
58dea17d SP	216	goal = damos_new_quota_goal(DAMOS_QUOTA_USER_INPUT, 10000);
11ddcfc2 SP	217	if (!goal)
11ddcfc2 SP	218	goto out;
58dea17d SP	219	goal->current_value = quota_autotune_feedback;
	220	damos_add_quota_goal(&scheme->quota, goal);
	221	}
	222
66d9faec SP	223	if (skip_anon) {
66d9faec SP	224	filter = damos_new_filter(DAMOS_FILTER_TYPE_ANON, true);
11ddcfc2 SP	225	if (!filter)
11ddcfc2 SP	226	goto out;
66d9faec SP	227	damos_add_filter(scheme, filter);
66d9faec SP	228	}
e035c280	229
11ddcfc2	230	err = damon_set_region_biggest_system_ram_default(param_target,
233f0b31 KX	231	&monitor_region_start,
233f0b31 KX	232	&monitor_region_end);
11ddcfc2 SP	233	if (err)
	234	goto out;
	235	err = damon_commit_ctx(ctx, param_ctx);
	236	out:
	237	damon_destroy_ctx(param_ctx);
	238	return err;
e035c280	239	}
43b0536c	240
e035c280 SP	241	static int damon_reclaim_turn(bool on)
	242	{
	243	int err;
	244
	245	if (!on) {
	246	err = damon_stop(&ctx, 1);
	247	if (!err)
	248	kdamond_pid = -1;
	249	return err;
43b0536c	250	}
e035c280 SP	251
e035c280 SP	252	err = damon_reclaim_apply_parameters();
43b0536c	253	if (err)
e035c280	254	return err;
43b0536c	255
8b9b0d33	256	err = damon_start(&ctx, 1, true);
e035c280 SP	257	if (err)
	258	return err;
	259	kdamond_pid = ctx->kdamond->pid;
	260	return 0;
43b0536c SP	261	}
43b0536c SP	262
d79905c7	263	static int damon_reclaim_enabled_store(const char *val,
059342d1 HT	264	const struct kernel_param *kp)
059342d1 HT	265	{
04e98764 SP	266	bool is_enabled = enabled;
	267	bool enable;
	268	int err;
059342d1	269
e6aff38b	270	err = kstrtobool(val, &enable);
04e98764 SP	271	if (err)
04e98764 SP	272	return err;
059342d1	273
04e98764 SP	274	if (is_enabled == enable)
04e98764 SP	275	return 0;
29492829	276
04e98764 SP	277	/* Called before init function. The function will handle this. */
	278	if (!ctx)
	279	goto set_param_out;
	280
	281	err = damon_reclaim_turn(enable);
	282	if (err)
	283	return err;
	284
	285	set_param_out:
	286	enabled = enable;
	287	return err;
059342d1 HT	288	}
	289
	290	static const struct kernel_param_ops enabled_param_ops = {
d79905c7	291	.set = damon_reclaim_enabled_store,
059342d1 HT	292	.get = param_get_bool,
	293	};
	294
	295	module_param_cb(enabled, &enabled_param_ops, &enabled, 0600);
	296	MODULE_PARM_DESC(enabled,
	297	"Enable or disable DAMON_RECLAIM (default: disabled)");
	298
f25ab3bd SP	299	static int damon_reclaim_handle_commit_inputs(void)
	300	{
	301	int err;
	302
	303	if (!commit_inputs)
	304	return 0;
	305
	306	err = damon_reclaim_apply_parameters();
	307	commit_inputs = false;
	308	return err;
	309	}
	310
60e52e7c SP	311	static int damon_reclaim_after_aggregation(struct damon_ctx *c)
	312	{
	313	struct damos *s;
	314
	315	/* update the stats parameter */
b71f3ea8 SP	316	damon_for_each_scheme(s, c)
b71f3ea8 SP	317	damon_reclaim_stat = s->stat;
e035c280	318
f25ab3bd	319	return damon_reclaim_handle_commit_inputs();
e035c280 SP	320	}
	321
	322	static int damon_reclaim_after_wmarks_check(struct damon_ctx *c)
	323	{
f25ab3bd	324	return damon_reclaim_handle_commit_inputs();
60e52e7c SP	325	}
60e52e7c SP	326
43b0536c SP	327	static int __init damon_reclaim_init(void)
43b0536c SP	328	{
7ae2c17f	329	int err = damon_modules_new_paddr_ctx_target(&ctx, &target);
43b0536c	330
7ae2c17f SP	331	if (err)
7ae2c17f SP	332	return err;
4d69c345	333
e035c280	334	ctx->callback.after_wmarks_check = damon_reclaim_after_wmarks_check;
60e52e7c	335	ctx->callback.after_aggregation = damon_reclaim_after_aggregation;
43b0536c	336
04e98764 SP	337	/* 'enabled' has set before this function, probably via command line */
	338	if (enabled)
	339	err = damon_reclaim_turn(true);
29492829	340
04e98764	341	return err;
43b0536c SP	342	}
	343
	344	module_init(damon_reclaim_init);