linux/mm/damon/reclaim.c
Christophe JAILLET e6aff38b2e mm/damon: use kstrtobool() instead of strtobool()
strtobool() is the same as kstrtobool().  However, the latter is more used
within the kernel.

In order to remove strtobool() and slightly simplify kstrtox.h, switch to
the other function name.

While at it, include the corresponding header file (<linux/kstrtox.h>)

Link: https://lkml.kernel.org/r/ed2b46489a513988688decb53850339cc228940c.1667336095.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-30 15:58:45 -08:00

266 lines
6.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* DAMON-based page reclamation
*
* Author: SeongJae Park <sj@kernel.org>
*/
#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);
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);
/*
* 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,
/* under the quota. */
&damon_reclaim_quota,
/* (De)activate this according to the watermarks. */
&damon_reclaim_wmarks);
}
static int damon_reclaim_apply_parameters(void)
{
struct damos *scheme;
int err = 0;
err = damon_set_attrs(ctx, &damon_reclaim_mon_attrs);
if (err)
return err;
/* Will be freed by next 'damon_set_schemes()' below */
scheme = damon_reclaim_new_scheme();
if (!scheme)
return -ENOMEM;
damon_set_schemes(ctx, &scheme, 1);
return damon_set_region_biggest_system_ram_default(target,
&monitor_region_start,
&monitor_region_end);
}
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);