linux/mm/damon/lru_sort.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

324 lines
8.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* DAMON-based LRU-lists Sorting
*
* Author: SeongJae Park <sj@kernel.org>
*/
#define pr_fmt(fmt) "damon-lru-sort: " 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_lru_sort."
/*
* Enable or disable DAMON_LRU_SORT.
*
* You can enable DAMON_LRU_SORT by setting the value of this parameter as
* ``Y``. Setting it as ``N`` disables DAMON_LRU_SORT. Note that
* DAMON_LRU_SORT could do no real monitoring and LRU-lists sorting due to the
* watermarks-based activation condition. Refer to below descriptions for the
* watermarks parameter for this.
*/
static bool enabled __read_mostly;
/*
* Make DAMON_LRU_SORT reads the input parameters again, except ``enabled``.
*
* Input parameters that updated while DAMON_LRU_SORT is running are not
* applied by default. Once this parameter is set as ``Y``, DAMON_LRU_SORT
* 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_LRU_SORT will be disabled.
*/
static bool commit_inputs __read_mostly;
module_param(commit_inputs, bool, 0600);
/*
* Access frequency threshold for hot memory regions identification in permil.
*
* If a memory region is accessed in frequency of this or higher,
* DAMON_LRU_SORT identifies the region as hot, and mark it as accessed on the
* LRU list, so that it could not be reclaimed under memory pressure. 50% by
* default.
*/
static unsigned long hot_thres_access_freq = 500;
module_param(hot_thres_access_freq, ulong, 0600);
/*
* Time threshold for cold memory regions identification in microseconds.
*
* If a memory region is not accessed for this or longer time, DAMON_LRU_SORT
* identifies the region as cold, and mark it as unaccessed on the LRU list, so
* that it could be reclaimed first under memory pressure. 120 seconds by
* default.
*/
static unsigned long cold_min_age __read_mostly = 120000000;
module_param(cold_min_age, ulong, 0600);
static struct damos_quota damon_lru_sort_quota = {
/* Use up to 10 ms per 1 sec, by default */
.ms = 10,
.sz = 0,
.reset_interval = 1000,
/* Within the quota, mark hotter regions accessed first. */
.weight_sz = 0,
.weight_nr_accesses = 1,
.weight_age = 0,
};
DEFINE_DAMON_MODULES_DAMOS_TIME_QUOTA(damon_lru_sort_quota);
static struct damos_watermarks damon_lru_sort_wmarks = {
.metric = DAMOS_WMARK_FREE_MEM_RATE,
.interval = 5000000, /* 5 seconds */
.high = 200, /* 20 percent */
.mid = 150, /* 15 percent */
.low = 50, /* 5 percent */
};
DEFINE_DAMON_MODULES_WMARKS_PARAMS(damon_lru_sort_wmarks);
static struct damon_attrs damon_lru_sort_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_lru_sort_mon_attrs);
/*
* Start of the target memory region in physical address.
*
* The start physical address of memory region that DAMON_LRU_SORT 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_LRU_SORT 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_LRU_SORT 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_lru_sort_hot_stat;
DEFINE_DAMON_MODULES_DAMOS_STATS_PARAMS(damon_lru_sort_hot_stat,
lru_sort_tried_hot_regions, lru_sorted_hot_regions,
hot_quota_exceeds);
static struct damos_stat damon_lru_sort_cold_stat;
DEFINE_DAMON_MODULES_DAMOS_STATS_PARAMS(damon_lru_sort_cold_stat,
lru_sort_tried_cold_regions, lru_sorted_cold_regions,
cold_quota_exceeds);
static struct damos_access_pattern damon_lru_sort_stub_pattern = {
/* Find regions having PAGE_SIZE or larger size */
.min_sz_region = PAGE_SIZE,
.max_sz_region = ULONG_MAX,
/* no matter its access frequency */
.min_nr_accesses = 0,
.max_nr_accesses = UINT_MAX,
/* no matter its age */
.min_age_region = 0,
.max_age_region = UINT_MAX,
};
static struct damon_ctx *ctx;
static struct damon_target *target;
static struct damos *damon_lru_sort_new_scheme(
struct damos_access_pattern *pattern, enum damos_action action)
{
struct damos_quota quota = damon_lru_sort_quota;
/* Use half of total quota for hot/cold pages sorting */
quota.ms = quota.ms / 2;
return damon_new_scheme(
/* find the pattern, and */
pattern,
/* (de)prioritize on LRU-lists */
action,
/* under the quota. */
&quota,
/* (De)activate this according to the watermarks. */
&damon_lru_sort_wmarks);
}
/* Create a DAMON-based operation scheme for hot memory regions */
static struct damos *damon_lru_sort_new_hot_scheme(unsigned int hot_thres)
{
struct damos_access_pattern pattern = damon_lru_sort_stub_pattern;
pattern.min_nr_accesses = hot_thres;
return damon_lru_sort_new_scheme(&pattern, DAMOS_LRU_PRIO);
}
/* Create a DAMON-based operation scheme for cold memory regions */
static struct damos *damon_lru_sort_new_cold_scheme(unsigned int cold_thres)
{
struct damos_access_pattern pattern = damon_lru_sort_stub_pattern;
pattern.max_nr_accesses = 0;
pattern.min_age_region = cold_thres;
return damon_lru_sort_new_scheme(&pattern, DAMOS_LRU_DEPRIO);
}
static int damon_lru_sort_apply_parameters(void)
{
struct damos *scheme;
unsigned int hot_thres, cold_thres;
int err = 0;
err = damon_set_attrs(ctx, &damon_lru_sort_mon_attrs);
if (err)
return err;
/* aggr_interval / sample_interval is the maximum nr_accesses */
hot_thres = damon_lru_sort_mon_attrs.aggr_interval /
damon_lru_sort_mon_attrs.sample_interval *
hot_thres_access_freq / 1000;
scheme = damon_lru_sort_new_hot_scheme(hot_thres);
if (!scheme)
return -ENOMEM;
damon_set_schemes(ctx, &scheme, 1);
cold_thres = cold_min_age / damon_lru_sort_mon_attrs.aggr_interval;
scheme = damon_lru_sort_new_cold_scheme(cold_thres);
if (!scheme)
return -ENOMEM;
damon_add_scheme(ctx, scheme);
return damon_set_region_biggest_system_ram_default(target,
&monitor_region_start,
&monitor_region_end);
}
static int damon_lru_sort_turn(bool on)
{
int err;
if (!on) {
err = damon_stop(&ctx, 1);
if (!err)
kdamond_pid = -1;
return err;
}
err = damon_lru_sort_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_lru_sort_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_lru_sort_turn(enable);
if (err)
return err;
set_param_out:
enabled = enable;
return err;
}
static const struct kernel_param_ops enabled_param_ops = {
.set = damon_lru_sort_enabled_store,
.get = param_get_bool,
};
module_param_cb(enabled, &enabled_param_ops, &enabled, 0600);
MODULE_PARM_DESC(enabled,
"Enable or disable DAMON_LRU_SORT (default: disabled)");
static int damon_lru_sort_handle_commit_inputs(void)
{
int err;
if (!commit_inputs)
return 0;
err = damon_lru_sort_apply_parameters();
commit_inputs = false;
return err;
}
static int damon_lru_sort_after_aggregation(struct damon_ctx *c)
{
struct damos *s;
/* update the stats parameter */
damon_for_each_scheme(s, c) {
if (s->action == DAMOS_LRU_PRIO)
damon_lru_sort_hot_stat = s->stat;
else if (s->action == DAMOS_LRU_DEPRIO)
damon_lru_sort_cold_stat = s->stat;
}
return damon_lru_sort_handle_commit_inputs();
}
static int damon_lru_sort_after_wmarks_check(struct damon_ctx *c)
{
return damon_lru_sort_handle_commit_inputs();
}
static int __init damon_lru_sort_init(void)
{
int err = damon_modules_new_paddr_ctx_target(&ctx, &target);
if (err)
return err;
ctx->callback.after_wmarks_check = damon_lru_sort_after_wmarks_check;
ctx->callback.after_aggregation = damon_lru_sort_after_aggregation;
/* 'enabled' has set before this function, probably via command line */
if (enabled)
err = damon_lru_sort_turn(true);
return err;
}
module_init(damon_lru_sort_init);