linux/mm/damon/sysfs.c
SeongJae Park 772c15e5ad mm/damon/sysfs-schemes: implement DAMOS-tried regions clear command
When there are huge number of DAMON regions that specific scheme actions
are tried to be applied, directories and files under 'tried_regions'
scheme directory could waste some memory.  Add another special input
keyword ('clear_schemes_tried_regions') for 'state' file of each kdamond
sysfs directory that can be used for cleanup of the 'tried_regions'
sub-directories.

[sj@kernel.org: skip regions clearing if the scheme directory was removed]
  Link: https://lkml.kernel.org/r/20221114182954.4745-3-sj@kernel.org
Link: https://lkml.kernel.org/r/20221101220328.95765-6-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-30 15:58:44 -08:00

1796 lines
43 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* DAMON sysfs Interface
*
* Copyright (c) 2022 SeongJae Park <sj@kernel.org>
*/
#include <linux/pid.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include "sysfs-common.h"
/*
* init region directory
*/
struct damon_sysfs_region {
struct kobject kobj;
struct damon_addr_range ar;
};
static struct damon_sysfs_region *damon_sysfs_region_alloc(void)
{
return kzalloc(sizeof(struct damon_sysfs_region), GFP_KERNEL);
}
static ssize_t start_show(struct kobject *kobj, struct kobj_attribute *attr,
char *buf)
{
struct damon_sysfs_region *region = container_of(kobj,
struct damon_sysfs_region, kobj);
return sysfs_emit(buf, "%lu\n", region->ar.start);
}
static ssize_t start_store(struct kobject *kobj, struct kobj_attribute *attr,
const char *buf, size_t count)
{
struct damon_sysfs_region *region = container_of(kobj,
struct damon_sysfs_region, kobj);
int err = kstrtoul(buf, 0, &region->ar.start);
return err ? err : count;
}
static ssize_t end_show(struct kobject *kobj, struct kobj_attribute *attr,
char *buf)
{
struct damon_sysfs_region *region = container_of(kobj,
struct damon_sysfs_region, kobj);
return sysfs_emit(buf, "%lu\n", region->ar.end);
}
static ssize_t end_store(struct kobject *kobj, struct kobj_attribute *attr,
const char *buf, size_t count)
{
struct damon_sysfs_region *region = container_of(kobj,
struct damon_sysfs_region, kobj);
int err = kstrtoul(buf, 0, &region->ar.end);
return err ? err : count;
}
static void damon_sysfs_region_release(struct kobject *kobj)
{
kfree(container_of(kobj, struct damon_sysfs_region, kobj));
}
static struct kobj_attribute damon_sysfs_region_start_attr =
__ATTR_RW_MODE(start, 0600);
static struct kobj_attribute damon_sysfs_region_end_attr =
__ATTR_RW_MODE(end, 0600);
static struct attribute *damon_sysfs_region_attrs[] = {
&damon_sysfs_region_start_attr.attr,
&damon_sysfs_region_end_attr.attr,
NULL,
};
ATTRIBUTE_GROUPS(damon_sysfs_region);
static struct kobj_type damon_sysfs_region_ktype = {
.release = damon_sysfs_region_release,
.sysfs_ops = &kobj_sysfs_ops,
.default_groups = damon_sysfs_region_groups,
};
/*
* init_regions directory
*/
struct damon_sysfs_regions {
struct kobject kobj;
struct damon_sysfs_region **regions_arr;
int nr;
};
static struct damon_sysfs_regions *damon_sysfs_regions_alloc(void)
{
return kzalloc(sizeof(struct damon_sysfs_regions), GFP_KERNEL);
}
static void damon_sysfs_regions_rm_dirs(struct damon_sysfs_regions *regions)
{
struct damon_sysfs_region **regions_arr = regions->regions_arr;
int i;
for (i = 0; i < regions->nr; i++)
kobject_put(&regions_arr[i]->kobj);
regions->nr = 0;
kfree(regions_arr);
regions->regions_arr = NULL;
}
static int damon_sysfs_regions_add_dirs(struct damon_sysfs_regions *regions,
int nr_regions)
{
struct damon_sysfs_region **regions_arr, *region;
int err, i;
damon_sysfs_regions_rm_dirs(regions);
if (!nr_regions)
return 0;
regions_arr = kmalloc_array(nr_regions, sizeof(*regions_arr),
GFP_KERNEL | __GFP_NOWARN);
if (!regions_arr)
return -ENOMEM;
regions->regions_arr = regions_arr;
for (i = 0; i < nr_regions; i++) {
region = damon_sysfs_region_alloc();
if (!region) {
damon_sysfs_regions_rm_dirs(regions);
return -ENOMEM;
}
err = kobject_init_and_add(&region->kobj,
&damon_sysfs_region_ktype, &regions->kobj,
"%d", i);
if (err) {
kobject_put(&region->kobj);
damon_sysfs_regions_rm_dirs(regions);
return err;
}
regions_arr[i] = region;
regions->nr++;
}
return 0;
}
static ssize_t nr_regions_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct damon_sysfs_regions *regions = container_of(kobj,
struct damon_sysfs_regions, kobj);
return sysfs_emit(buf, "%d\n", regions->nr);
}
static ssize_t nr_regions_store(struct kobject *kobj,
struct kobj_attribute *attr, const char *buf, size_t count)
{
struct damon_sysfs_regions *regions;
int nr, err = kstrtoint(buf, 0, &nr);
if (err)
return err;
if (nr < 0)
return -EINVAL;
regions = container_of(kobj, struct damon_sysfs_regions, kobj);
if (!mutex_trylock(&damon_sysfs_lock))
return -EBUSY;
err = damon_sysfs_regions_add_dirs(regions, nr);
mutex_unlock(&damon_sysfs_lock);
if (err)
return err;
return count;
}
static void damon_sysfs_regions_release(struct kobject *kobj)
{
kfree(container_of(kobj, struct damon_sysfs_regions, kobj));
}
static struct kobj_attribute damon_sysfs_regions_nr_attr =
__ATTR_RW_MODE(nr_regions, 0600);
static struct attribute *damon_sysfs_regions_attrs[] = {
&damon_sysfs_regions_nr_attr.attr,
NULL,
};
ATTRIBUTE_GROUPS(damon_sysfs_regions);
static struct kobj_type damon_sysfs_regions_ktype = {
.release = damon_sysfs_regions_release,
.sysfs_ops = &kobj_sysfs_ops,
.default_groups = damon_sysfs_regions_groups,
};
/*
* target directory
*/
struct damon_sysfs_target {
struct kobject kobj;
struct damon_sysfs_regions *regions;
int pid;
};
static struct damon_sysfs_target *damon_sysfs_target_alloc(void)
{
return kzalloc(sizeof(struct damon_sysfs_target), GFP_KERNEL);
}
static int damon_sysfs_target_add_dirs(struct damon_sysfs_target *target)
{
struct damon_sysfs_regions *regions = damon_sysfs_regions_alloc();
int err;
if (!regions)
return -ENOMEM;
err = kobject_init_and_add(&regions->kobj, &damon_sysfs_regions_ktype,
&target->kobj, "regions");
if (err)
kobject_put(&regions->kobj);
else
target->regions = regions;
return err;
}
static void damon_sysfs_target_rm_dirs(struct damon_sysfs_target *target)
{
damon_sysfs_regions_rm_dirs(target->regions);
kobject_put(&target->regions->kobj);
}
static ssize_t pid_target_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct damon_sysfs_target *target = container_of(kobj,
struct damon_sysfs_target, kobj);
return sysfs_emit(buf, "%d\n", target->pid);
}
static ssize_t pid_target_store(struct kobject *kobj,
struct kobj_attribute *attr, const char *buf, size_t count)
{
struct damon_sysfs_target *target = container_of(kobj,
struct damon_sysfs_target, kobj);
int err = kstrtoint(buf, 0, &target->pid);
if (err)
return -EINVAL;
return count;
}
static void damon_sysfs_target_release(struct kobject *kobj)
{
kfree(container_of(kobj, struct damon_sysfs_target, kobj));
}
static struct kobj_attribute damon_sysfs_target_pid_attr =
__ATTR_RW_MODE(pid_target, 0600);
static struct attribute *damon_sysfs_target_attrs[] = {
&damon_sysfs_target_pid_attr.attr,
NULL,
};
ATTRIBUTE_GROUPS(damon_sysfs_target);
static struct kobj_type damon_sysfs_target_ktype = {
.release = damon_sysfs_target_release,
.sysfs_ops = &kobj_sysfs_ops,
.default_groups = damon_sysfs_target_groups,
};
/*
* targets directory
*/
struct damon_sysfs_targets {
struct kobject kobj;
struct damon_sysfs_target **targets_arr;
int nr;
};
static struct damon_sysfs_targets *damon_sysfs_targets_alloc(void)
{
return kzalloc(sizeof(struct damon_sysfs_targets), GFP_KERNEL);
}
static void damon_sysfs_targets_rm_dirs(struct damon_sysfs_targets *targets)
{
struct damon_sysfs_target **targets_arr = targets->targets_arr;
int i;
for (i = 0; i < targets->nr; i++) {
damon_sysfs_target_rm_dirs(targets_arr[i]);
kobject_put(&targets_arr[i]->kobj);
}
targets->nr = 0;
kfree(targets_arr);
targets->targets_arr = NULL;
}
static int damon_sysfs_targets_add_dirs(struct damon_sysfs_targets *targets,
int nr_targets)
{
struct damon_sysfs_target **targets_arr, *target;
int err, i;
damon_sysfs_targets_rm_dirs(targets);
if (!nr_targets)
return 0;
targets_arr = kmalloc_array(nr_targets, sizeof(*targets_arr),
GFP_KERNEL | __GFP_NOWARN);
if (!targets_arr)
return -ENOMEM;
targets->targets_arr = targets_arr;
for (i = 0; i < nr_targets; i++) {
target = damon_sysfs_target_alloc();
if (!target) {
damon_sysfs_targets_rm_dirs(targets);
return -ENOMEM;
}
err = kobject_init_and_add(&target->kobj,
&damon_sysfs_target_ktype, &targets->kobj,
"%d", i);
if (err)
goto out;
err = damon_sysfs_target_add_dirs(target);
if (err)
goto out;
targets_arr[i] = target;
targets->nr++;
}
return 0;
out:
damon_sysfs_targets_rm_dirs(targets);
kobject_put(&target->kobj);
return err;
}
static ssize_t nr_targets_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct damon_sysfs_targets *targets = container_of(kobj,
struct damon_sysfs_targets, kobj);
return sysfs_emit(buf, "%d\n", targets->nr);
}
static ssize_t nr_targets_store(struct kobject *kobj,
struct kobj_attribute *attr, const char *buf, size_t count)
{
struct damon_sysfs_targets *targets;
int nr, err = kstrtoint(buf, 0, &nr);
if (err)
return err;
if (nr < 0)
return -EINVAL;
targets = container_of(kobj, struct damon_sysfs_targets, kobj);
if (!mutex_trylock(&damon_sysfs_lock))
return -EBUSY;
err = damon_sysfs_targets_add_dirs(targets, nr);
mutex_unlock(&damon_sysfs_lock);
if (err)
return err;
return count;
}
static void damon_sysfs_targets_release(struct kobject *kobj)
{
kfree(container_of(kobj, struct damon_sysfs_targets, kobj));
}
static struct kobj_attribute damon_sysfs_targets_nr_attr =
__ATTR_RW_MODE(nr_targets, 0600);
static struct attribute *damon_sysfs_targets_attrs[] = {
&damon_sysfs_targets_nr_attr.attr,
NULL,
};
ATTRIBUTE_GROUPS(damon_sysfs_targets);
static struct kobj_type damon_sysfs_targets_ktype = {
.release = damon_sysfs_targets_release,
.sysfs_ops = &kobj_sysfs_ops,
.default_groups = damon_sysfs_targets_groups,
};
/*
* intervals directory
*/
struct damon_sysfs_intervals {
struct kobject kobj;
unsigned long sample_us;
unsigned long aggr_us;
unsigned long update_us;
};
static struct damon_sysfs_intervals *damon_sysfs_intervals_alloc(
unsigned long sample_us, unsigned long aggr_us,
unsigned long update_us)
{
struct damon_sysfs_intervals *intervals = kmalloc(sizeof(*intervals),
GFP_KERNEL);
if (!intervals)
return NULL;
intervals->kobj = (struct kobject){};
intervals->sample_us = sample_us;
intervals->aggr_us = aggr_us;
intervals->update_us = update_us;
return intervals;
}
static ssize_t sample_us_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct damon_sysfs_intervals *intervals = container_of(kobj,
struct damon_sysfs_intervals, kobj);
return sysfs_emit(buf, "%lu\n", intervals->sample_us);
}
static ssize_t sample_us_store(struct kobject *kobj,
struct kobj_attribute *attr, const char *buf, size_t count)
{
struct damon_sysfs_intervals *intervals = container_of(kobj,
struct damon_sysfs_intervals, kobj);
unsigned long us;
int err = kstrtoul(buf, 0, &us);
if (err)
return err;
intervals->sample_us = us;
return count;
}
static ssize_t aggr_us_show(struct kobject *kobj, struct kobj_attribute *attr,
char *buf)
{
struct damon_sysfs_intervals *intervals = container_of(kobj,
struct damon_sysfs_intervals, kobj);
return sysfs_emit(buf, "%lu\n", intervals->aggr_us);
}
static ssize_t aggr_us_store(struct kobject *kobj, struct kobj_attribute *attr,
const char *buf, size_t count)
{
struct damon_sysfs_intervals *intervals = container_of(kobj,
struct damon_sysfs_intervals, kobj);
unsigned long us;
int err = kstrtoul(buf, 0, &us);
if (err)
return err;
intervals->aggr_us = us;
return count;
}
static ssize_t update_us_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct damon_sysfs_intervals *intervals = container_of(kobj,
struct damon_sysfs_intervals, kobj);
return sysfs_emit(buf, "%lu\n", intervals->update_us);
}
static ssize_t update_us_store(struct kobject *kobj,
struct kobj_attribute *attr, const char *buf, size_t count)
{
struct damon_sysfs_intervals *intervals = container_of(kobj,
struct damon_sysfs_intervals, kobj);
unsigned long us;
int err = kstrtoul(buf, 0, &us);
if (err)
return err;
intervals->update_us = us;
return count;
}
static void damon_sysfs_intervals_release(struct kobject *kobj)
{
kfree(container_of(kobj, struct damon_sysfs_intervals, kobj));
}
static struct kobj_attribute damon_sysfs_intervals_sample_us_attr =
__ATTR_RW_MODE(sample_us, 0600);
static struct kobj_attribute damon_sysfs_intervals_aggr_us_attr =
__ATTR_RW_MODE(aggr_us, 0600);
static struct kobj_attribute damon_sysfs_intervals_update_us_attr =
__ATTR_RW_MODE(update_us, 0600);
static struct attribute *damon_sysfs_intervals_attrs[] = {
&damon_sysfs_intervals_sample_us_attr.attr,
&damon_sysfs_intervals_aggr_us_attr.attr,
&damon_sysfs_intervals_update_us_attr.attr,
NULL,
};
ATTRIBUTE_GROUPS(damon_sysfs_intervals);
static struct kobj_type damon_sysfs_intervals_ktype = {
.release = damon_sysfs_intervals_release,
.sysfs_ops = &kobj_sysfs_ops,
.default_groups = damon_sysfs_intervals_groups,
};
/*
* monitoring_attrs directory
*/
struct damon_sysfs_attrs {
struct kobject kobj;
struct damon_sysfs_intervals *intervals;
struct damon_sysfs_ul_range *nr_regions_range;
};
static struct damon_sysfs_attrs *damon_sysfs_attrs_alloc(void)
{
struct damon_sysfs_attrs *attrs = kmalloc(sizeof(*attrs), GFP_KERNEL);
if (!attrs)
return NULL;
attrs->kobj = (struct kobject){};
return attrs;
}
static int damon_sysfs_attrs_add_dirs(struct damon_sysfs_attrs *attrs)
{
struct damon_sysfs_intervals *intervals;
struct damon_sysfs_ul_range *nr_regions_range;
int err;
intervals = damon_sysfs_intervals_alloc(5000, 100000, 60000000);
if (!intervals)
return -ENOMEM;
err = kobject_init_and_add(&intervals->kobj,
&damon_sysfs_intervals_ktype, &attrs->kobj,
"intervals");
if (err)
goto put_intervals_out;
attrs->intervals = intervals;
nr_regions_range = damon_sysfs_ul_range_alloc(10, 1000);
if (!nr_regions_range) {
err = -ENOMEM;
goto put_intervals_out;
}
err = kobject_init_and_add(&nr_regions_range->kobj,
&damon_sysfs_ul_range_ktype, &attrs->kobj,
"nr_regions");
if (err)
goto put_nr_regions_intervals_out;
attrs->nr_regions_range = nr_regions_range;
return 0;
put_nr_regions_intervals_out:
kobject_put(&nr_regions_range->kobj);
attrs->nr_regions_range = NULL;
put_intervals_out:
kobject_put(&intervals->kobj);
attrs->intervals = NULL;
return err;
}
static void damon_sysfs_attrs_rm_dirs(struct damon_sysfs_attrs *attrs)
{
kobject_put(&attrs->nr_regions_range->kobj);
kobject_put(&attrs->intervals->kobj);
}
static void damon_sysfs_attrs_release(struct kobject *kobj)
{
kfree(container_of(kobj, struct damon_sysfs_attrs, kobj));
}
static struct attribute *damon_sysfs_attrs_attrs[] = {
NULL,
};
ATTRIBUTE_GROUPS(damon_sysfs_attrs);
static struct kobj_type damon_sysfs_attrs_ktype = {
.release = damon_sysfs_attrs_release,
.sysfs_ops = &kobj_sysfs_ops,
.default_groups = damon_sysfs_attrs_groups,
};
/*
* context directory
*/
/* This should match with enum damon_ops_id */
static const char * const damon_sysfs_ops_strs[] = {
"vaddr",
"fvaddr",
"paddr",
};
struct damon_sysfs_context {
struct kobject kobj;
enum damon_ops_id ops_id;
struct damon_sysfs_attrs *attrs;
struct damon_sysfs_targets *targets;
struct damon_sysfs_schemes *schemes;
};
static struct damon_sysfs_context *damon_sysfs_context_alloc(
enum damon_ops_id ops_id)
{
struct damon_sysfs_context *context = kmalloc(sizeof(*context),
GFP_KERNEL);
if (!context)
return NULL;
context->kobj = (struct kobject){};
context->ops_id = ops_id;
return context;
}
static int damon_sysfs_context_set_attrs(struct damon_sysfs_context *context)
{
struct damon_sysfs_attrs *attrs = damon_sysfs_attrs_alloc();
int err;
if (!attrs)
return -ENOMEM;
err = kobject_init_and_add(&attrs->kobj, &damon_sysfs_attrs_ktype,
&context->kobj, "monitoring_attrs");
if (err)
goto out;
err = damon_sysfs_attrs_add_dirs(attrs);
if (err)
goto out;
context->attrs = attrs;
return 0;
out:
kobject_put(&attrs->kobj);
return err;
}
static int damon_sysfs_context_set_targets(struct damon_sysfs_context *context)
{
struct damon_sysfs_targets *targets = damon_sysfs_targets_alloc();
int err;
if (!targets)
return -ENOMEM;
err = kobject_init_and_add(&targets->kobj, &damon_sysfs_targets_ktype,
&context->kobj, "targets");
if (err) {
kobject_put(&targets->kobj);
return err;
}
context->targets = targets;
return 0;
}
static int damon_sysfs_context_set_schemes(struct damon_sysfs_context *context)
{
struct damon_sysfs_schemes *schemes = damon_sysfs_schemes_alloc();
int err;
if (!schemes)
return -ENOMEM;
err = kobject_init_and_add(&schemes->kobj, &damon_sysfs_schemes_ktype,
&context->kobj, "schemes");
if (err) {
kobject_put(&schemes->kobj);
return err;
}
context->schemes = schemes;
return 0;
}
static int damon_sysfs_context_add_dirs(struct damon_sysfs_context *context)
{
int err;
err = damon_sysfs_context_set_attrs(context);
if (err)
return err;
err = damon_sysfs_context_set_targets(context);
if (err)
goto put_attrs_out;
err = damon_sysfs_context_set_schemes(context);
if (err)
goto put_targets_attrs_out;
return 0;
put_targets_attrs_out:
kobject_put(&context->targets->kobj);
context->targets = NULL;
put_attrs_out:
kobject_put(&context->attrs->kobj);
context->attrs = NULL;
return err;
}
static void damon_sysfs_context_rm_dirs(struct damon_sysfs_context *context)
{
damon_sysfs_attrs_rm_dirs(context->attrs);
kobject_put(&context->attrs->kobj);
damon_sysfs_targets_rm_dirs(context->targets);
kobject_put(&context->targets->kobj);
damon_sysfs_schemes_rm_dirs(context->schemes);
kobject_put(&context->schemes->kobj);
}
static ssize_t avail_operations_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
enum damon_ops_id id;
int len = 0;
for (id = 0; id < NR_DAMON_OPS; id++) {
if (!damon_is_registered_ops(id))
continue;
len += sysfs_emit_at(buf, len, "%s\n",
damon_sysfs_ops_strs[id]);
}
return len;
}
static ssize_t operations_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct damon_sysfs_context *context = container_of(kobj,
struct damon_sysfs_context, kobj);
return sysfs_emit(buf, "%s\n", damon_sysfs_ops_strs[context->ops_id]);
}
static ssize_t operations_store(struct kobject *kobj,
struct kobj_attribute *attr, const char *buf, size_t count)
{
struct damon_sysfs_context *context = container_of(kobj,
struct damon_sysfs_context, kobj);
enum damon_ops_id id;
for (id = 0; id < NR_DAMON_OPS; id++) {
if (sysfs_streq(buf, damon_sysfs_ops_strs[id])) {
context->ops_id = id;
return count;
}
}
return -EINVAL;
}
static void damon_sysfs_context_release(struct kobject *kobj)
{
kfree(container_of(kobj, struct damon_sysfs_context, kobj));
}
static struct kobj_attribute damon_sysfs_context_avail_operations_attr =
__ATTR_RO_MODE(avail_operations, 0400);
static struct kobj_attribute damon_sysfs_context_operations_attr =
__ATTR_RW_MODE(operations, 0600);
static struct attribute *damon_sysfs_context_attrs[] = {
&damon_sysfs_context_avail_operations_attr.attr,
&damon_sysfs_context_operations_attr.attr,
NULL,
};
ATTRIBUTE_GROUPS(damon_sysfs_context);
static struct kobj_type damon_sysfs_context_ktype = {
.release = damon_sysfs_context_release,
.sysfs_ops = &kobj_sysfs_ops,
.default_groups = damon_sysfs_context_groups,
};
/*
* contexts directory
*/
struct damon_sysfs_contexts {
struct kobject kobj;
struct damon_sysfs_context **contexts_arr;
int nr;
};
static struct damon_sysfs_contexts *damon_sysfs_contexts_alloc(void)
{
return kzalloc(sizeof(struct damon_sysfs_contexts), GFP_KERNEL);
}
static void damon_sysfs_contexts_rm_dirs(struct damon_sysfs_contexts *contexts)
{
struct damon_sysfs_context **contexts_arr = contexts->contexts_arr;
int i;
for (i = 0; i < contexts->nr; i++) {
damon_sysfs_context_rm_dirs(contexts_arr[i]);
kobject_put(&contexts_arr[i]->kobj);
}
contexts->nr = 0;
kfree(contexts_arr);
contexts->contexts_arr = NULL;
}
static int damon_sysfs_contexts_add_dirs(struct damon_sysfs_contexts *contexts,
int nr_contexts)
{
struct damon_sysfs_context **contexts_arr, *context;
int err, i;
damon_sysfs_contexts_rm_dirs(contexts);
if (!nr_contexts)
return 0;
contexts_arr = kmalloc_array(nr_contexts, sizeof(*contexts_arr),
GFP_KERNEL | __GFP_NOWARN);
if (!contexts_arr)
return -ENOMEM;
contexts->contexts_arr = contexts_arr;
for (i = 0; i < nr_contexts; i++) {
context = damon_sysfs_context_alloc(DAMON_OPS_VADDR);
if (!context) {
damon_sysfs_contexts_rm_dirs(contexts);
return -ENOMEM;
}
err = kobject_init_and_add(&context->kobj,
&damon_sysfs_context_ktype, &contexts->kobj,
"%d", i);
if (err)
goto out;
err = damon_sysfs_context_add_dirs(context);
if (err)
goto out;
contexts_arr[i] = context;
contexts->nr++;
}
return 0;
out:
damon_sysfs_contexts_rm_dirs(contexts);
kobject_put(&context->kobj);
return err;
}
static ssize_t nr_contexts_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct damon_sysfs_contexts *contexts = container_of(kobj,
struct damon_sysfs_contexts, kobj);
return sysfs_emit(buf, "%d\n", contexts->nr);
}
static ssize_t nr_contexts_store(struct kobject *kobj,
struct kobj_attribute *attr, const char *buf, size_t count)
{
struct damon_sysfs_contexts *contexts;
int nr, err;
err = kstrtoint(buf, 0, &nr);
if (err)
return err;
/* TODO: support multiple contexts per kdamond */
if (nr < 0 || 1 < nr)
return -EINVAL;
contexts = container_of(kobj, struct damon_sysfs_contexts, kobj);
if (!mutex_trylock(&damon_sysfs_lock))
return -EBUSY;
err = damon_sysfs_contexts_add_dirs(contexts, nr);
mutex_unlock(&damon_sysfs_lock);
if (err)
return err;
return count;
}
static void damon_sysfs_contexts_release(struct kobject *kobj)
{
kfree(container_of(kobj, struct damon_sysfs_contexts, kobj));
}
static struct kobj_attribute damon_sysfs_contexts_nr_attr
= __ATTR_RW_MODE(nr_contexts, 0600);
static struct attribute *damon_sysfs_contexts_attrs[] = {
&damon_sysfs_contexts_nr_attr.attr,
NULL,
};
ATTRIBUTE_GROUPS(damon_sysfs_contexts);
static struct kobj_type damon_sysfs_contexts_ktype = {
.release = damon_sysfs_contexts_release,
.sysfs_ops = &kobj_sysfs_ops,
.default_groups = damon_sysfs_contexts_groups,
};
/*
* kdamond directory
*/
struct damon_sysfs_kdamond {
struct kobject kobj;
struct damon_sysfs_contexts *contexts;
struct damon_ctx *damon_ctx;
};
static struct damon_sysfs_kdamond *damon_sysfs_kdamond_alloc(void)
{
return kzalloc(sizeof(struct damon_sysfs_kdamond), GFP_KERNEL);
}
static int damon_sysfs_kdamond_add_dirs(struct damon_sysfs_kdamond *kdamond)
{
struct damon_sysfs_contexts *contexts;
int err;
contexts = damon_sysfs_contexts_alloc();
if (!contexts)
return -ENOMEM;
err = kobject_init_and_add(&contexts->kobj,
&damon_sysfs_contexts_ktype, &kdamond->kobj,
"contexts");
if (err) {
kobject_put(&contexts->kobj);
return err;
}
kdamond->contexts = contexts;
return err;
}
static void damon_sysfs_kdamond_rm_dirs(struct damon_sysfs_kdamond *kdamond)
{
damon_sysfs_contexts_rm_dirs(kdamond->contexts);
kobject_put(&kdamond->contexts->kobj);
}
static bool damon_sysfs_ctx_running(struct damon_ctx *ctx)
{
bool running;
mutex_lock(&ctx->kdamond_lock);
running = ctx->kdamond != NULL;
mutex_unlock(&ctx->kdamond_lock);
return running;
}
/*
* enum damon_sysfs_cmd - Commands for a specific kdamond.
*/
enum damon_sysfs_cmd {
/* @DAMON_SYSFS_CMD_ON: Turn the kdamond on. */
DAMON_SYSFS_CMD_ON,
/* @DAMON_SYSFS_CMD_OFF: Turn the kdamond off. */
DAMON_SYSFS_CMD_OFF,
/* @DAMON_SYSFS_CMD_COMMIT: Update kdamond inputs. */
DAMON_SYSFS_CMD_COMMIT,
/*
* @DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS: Update scheme stats sysfs
* files.
*/
DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS,
/*
* @DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS: Update schemes tried
* regions
*/
DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS,
/*
* @DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS: Clear schemes tried
* regions
*/
DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS,
/*
* @NR_DAMON_SYSFS_CMDS: Total number of DAMON sysfs commands.
*/
NR_DAMON_SYSFS_CMDS,
};
/* Should match with enum damon_sysfs_cmd */
static const char * const damon_sysfs_cmd_strs[] = {
"on",
"off",
"commit",
"update_schemes_stats",
"update_schemes_tried_regions",
"clear_schemes_tried_regions",
};
/*
* struct damon_sysfs_cmd_request - A request to the DAMON callback.
* @cmd: The command that needs to be handled by the callback.
* @kdamond: The kobject wrapper that associated to the kdamond thread.
*
* This structure represents a sysfs command request that need to access some
* DAMON context-internal data. Because DAMON context-internal data can be
* safely accessed from DAMON callbacks without additional synchronization, the
* request will be handled by the DAMON callback. None-``NULL`` @kdamond means
* the request is valid.
*/
struct damon_sysfs_cmd_request {
enum damon_sysfs_cmd cmd;
struct damon_sysfs_kdamond *kdamond;
};
/* Current DAMON callback request. Protected by damon_sysfs_lock. */
static struct damon_sysfs_cmd_request damon_sysfs_cmd_request;
static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
char *buf)
{
struct damon_sysfs_kdamond *kdamond = container_of(kobj,
struct damon_sysfs_kdamond, kobj);
struct damon_ctx *ctx = kdamond->damon_ctx;
bool running;
if (!ctx)
running = false;
else
running = damon_sysfs_ctx_running(ctx);
return sysfs_emit(buf, "%s\n", running ?
damon_sysfs_cmd_strs[DAMON_SYSFS_CMD_ON] :
damon_sysfs_cmd_strs[DAMON_SYSFS_CMD_OFF]);
}
static int damon_sysfs_set_attrs(struct damon_ctx *ctx,
struct damon_sysfs_attrs *sys_attrs)
{
struct damon_sysfs_intervals *sys_intervals = sys_attrs->intervals;
struct damon_sysfs_ul_range *sys_nr_regions =
sys_attrs->nr_regions_range;
struct damon_attrs attrs = {
.sample_interval = sys_intervals->sample_us,
.aggr_interval = sys_intervals->aggr_us,
.ops_update_interval = sys_intervals->update_us,
.min_nr_regions = sys_nr_regions->min,
.max_nr_regions = sys_nr_regions->max,
};
return damon_set_attrs(ctx, &attrs);
}
static void damon_sysfs_destroy_targets(struct damon_ctx *ctx)
{
struct damon_target *t, *next;
bool has_pid = damon_target_has_pid(ctx);
damon_for_each_target_safe(t, next, ctx) {
if (has_pid)
put_pid(t->pid);
damon_destroy_target(t);
}
}
static int damon_sysfs_set_regions(struct damon_target *t,
struct damon_sysfs_regions *sysfs_regions)
{
struct damon_addr_range *ranges = kmalloc_array(sysfs_regions->nr,
sizeof(*ranges), GFP_KERNEL | __GFP_NOWARN);
int i, err = -EINVAL;
if (!ranges)
return -ENOMEM;
for (i = 0; i < sysfs_regions->nr; i++) {
struct damon_sysfs_region *sys_region =
sysfs_regions->regions_arr[i];
if (sys_region->ar.start > sys_region->ar.end)
goto out;
ranges[i].start = sys_region->ar.start;
ranges[i].end = sys_region->ar.end;
if (i == 0)
continue;
if (ranges[i - 1].end > ranges[i].start)
goto out;
}
err = damon_set_regions(t, ranges, sysfs_regions->nr);
out:
kfree(ranges);
return err;
}
static int damon_sysfs_add_target(struct damon_sysfs_target *sys_target,
struct damon_ctx *ctx)
{
struct damon_target *t = damon_new_target();
int err = -EINVAL;
if (!t)
return -ENOMEM;
damon_add_target(ctx, t);
if (damon_target_has_pid(ctx)) {
t->pid = find_get_pid(sys_target->pid);
if (!t->pid)
goto destroy_targets_out;
}
err = damon_sysfs_set_regions(t, sys_target->regions);
if (err)
goto destroy_targets_out;
return 0;
destroy_targets_out:
damon_sysfs_destroy_targets(ctx);
return err;
}
/*
* Search a target in a context that corresponds to the sysfs target input.
*
* Return: pointer to the target if found, NULL if not found, or negative
* error code if the search failed.
*/
static struct damon_target *damon_sysfs_existing_target(
struct damon_sysfs_target *sys_target, struct damon_ctx *ctx)
{
struct pid *pid;
struct damon_target *t;
if (!damon_target_has_pid(ctx)) {
/* Up to only one target for paddr could exist */
damon_for_each_target(t, ctx)
return t;
return NULL;
}
/* ops.id should be DAMON_OPS_VADDR or DAMON_OPS_FVADDR */
pid = find_get_pid(sys_target->pid);
if (!pid)
return ERR_PTR(-EINVAL);
damon_for_each_target(t, ctx) {
if (t->pid == pid) {
put_pid(pid);
return t;
}
}
put_pid(pid);
return NULL;
}
static int damon_sysfs_set_targets(struct damon_ctx *ctx,
struct damon_sysfs_targets *sysfs_targets)
{
int i, err;
/* Multiple physical address space monitoring targets makes no sense */
if (ctx->ops.id == DAMON_OPS_PADDR && sysfs_targets->nr > 1)
return -EINVAL;
for (i = 0; i < sysfs_targets->nr; i++) {
struct damon_sysfs_target *st = sysfs_targets->targets_arr[i];
struct damon_target *t = damon_sysfs_existing_target(st, ctx);
if (IS_ERR(t))
return PTR_ERR(t);
if (!t)
err = damon_sysfs_add_target(st, ctx);
else
err = damon_sysfs_set_regions(t, st->regions);
if (err)
return err;
}
return 0;
}
static void damon_sysfs_before_terminate(struct damon_ctx *ctx)
{
struct damon_target *t, *next;
struct damon_sysfs_kdamond *kdamond;
/* damon_sysfs_schemes_update_regions_stop() might not yet called */
kdamond = damon_sysfs_cmd_request.kdamond;
if (kdamond && damon_sysfs_cmd_request.cmd ==
DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS &&
ctx == kdamond->damon_ctx) {
damon_sysfs_schemes_update_regions_stop(ctx);
mutex_unlock(&damon_sysfs_lock);
}
if (!damon_target_has_pid(ctx))
return;
mutex_lock(&ctx->kdamond_lock);
damon_for_each_target_safe(t, next, ctx) {
put_pid(t->pid);
damon_destroy_target(t);
}
mutex_unlock(&ctx->kdamond_lock);
}
/*
* damon_sysfs_upd_schemes_stats() - Update schemes stats sysfs files.
* @kdamond: The kobject wrapper that associated to the kdamond thread.
*
* This function reads the schemes stats of specific kdamond and update the
* related values for sysfs files. This function should be called from DAMON
* callbacks while holding ``damon_syfs_lock``, to safely access the DAMON
* contexts-internal data and DAMON sysfs variables.
*/
static int damon_sysfs_upd_schemes_stats(struct damon_sysfs_kdamond *kdamond)
{
struct damon_ctx *ctx = kdamond->damon_ctx;
if (!ctx)
return -EINVAL;
damon_sysfs_schemes_update_stats(
kdamond->contexts->contexts_arr[0]->schemes, ctx);
return 0;
}
static int damon_sysfs_upd_schemes_regions_start(
struct damon_sysfs_kdamond *kdamond)
{
struct damon_ctx *ctx = kdamond->damon_ctx;
if (!ctx)
return -EINVAL;
return damon_sysfs_schemes_update_regions_start(
kdamond->contexts->contexts_arr[0]->schemes, ctx);
}
static int damon_sysfs_upd_schemes_regions_stop(
struct damon_sysfs_kdamond *kdamond)
{
struct damon_ctx *ctx = kdamond->damon_ctx;
if (!ctx)
return -EINVAL;
return damon_sysfs_schemes_update_regions_stop(ctx);
}
static int damon_sysfs_clear_schemes_regions(
struct damon_sysfs_kdamond *kdamond)
{
struct damon_ctx *ctx = kdamond->damon_ctx;
if (!ctx)
return -EINVAL;
return damon_sysfs_schemes_clear_regions(
kdamond->contexts->contexts_arr[0]->schemes, ctx);
}
static inline bool damon_sysfs_kdamond_running(
struct damon_sysfs_kdamond *kdamond)
{
return kdamond->damon_ctx &&
damon_sysfs_ctx_running(kdamond->damon_ctx);
}
static int damon_sysfs_apply_inputs(struct damon_ctx *ctx,
struct damon_sysfs_context *sys_ctx)
{
int err;
err = damon_select_ops(ctx, sys_ctx->ops_id);
if (err)
return err;
err = damon_sysfs_set_attrs(ctx, sys_ctx->attrs);
if (err)
return err;
err = damon_sysfs_set_targets(ctx, sys_ctx->targets);
if (err)
return err;
return damon_sysfs_set_schemes(ctx, sys_ctx->schemes);
}
/*
* damon_sysfs_commit_input() - Commit user inputs to a running kdamond.
* @kdamond: The kobject wrapper for the associated kdamond.
*
* If the sysfs input is wrong, the kdamond will be terminated.
*/
static int damon_sysfs_commit_input(struct damon_sysfs_kdamond *kdamond)
{
if (!damon_sysfs_kdamond_running(kdamond))
return -EINVAL;
/* TODO: Support multiple contexts per kdamond */
if (kdamond->contexts->nr != 1)
return -EINVAL;
return damon_sysfs_apply_inputs(kdamond->damon_ctx,
kdamond->contexts->contexts_arr[0]);
}
/*
* damon_sysfs_cmd_request_callback() - DAMON callback for handling requests.
* @c: The DAMON context of the callback.
*
* This function is periodically called back from the kdamond thread for @c.
* Then, it checks if there is a waiting DAMON sysfs request and handles it.
*/
static int damon_sysfs_cmd_request_callback(struct damon_ctx *c)
{
struct damon_sysfs_kdamond *kdamond;
static bool damon_sysfs_schemes_regions_updating;
int err = 0;
/* avoid deadlock due to concurrent state_store('off') */
if (!damon_sysfs_schemes_regions_updating &&
!mutex_trylock(&damon_sysfs_lock))
return 0;
kdamond = damon_sysfs_cmd_request.kdamond;
if (!kdamond || kdamond->damon_ctx != c)
goto out;
switch (damon_sysfs_cmd_request.cmd) {
case DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS:
err = damon_sysfs_upd_schemes_stats(kdamond);
break;
case DAMON_SYSFS_CMD_COMMIT:
err = damon_sysfs_commit_input(kdamond);
break;
case DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS:
if (!damon_sysfs_schemes_regions_updating) {
err = damon_sysfs_upd_schemes_regions_start(kdamond);
if (!err) {
damon_sysfs_schemes_regions_updating = true;
goto keep_lock_out;
}
} else {
err = damon_sysfs_upd_schemes_regions_stop(kdamond);
damon_sysfs_schemes_regions_updating = false;
}
break;
case DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS:
err = damon_sysfs_clear_schemes_regions(kdamond);
break;
default:
break;
}
/* Mark the request as invalid now. */
damon_sysfs_cmd_request.kdamond = NULL;
out:
if (!damon_sysfs_schemes_regions_updating)
mutex_unlock(&damon_sysfs_lock);
keep_lock_out:
return err;
}
static struct damon_ctx *damon_sysfs_build_ctx(
struct damon_sysfs_context *sys_ctx)
{
struct damon_ctx *ctx = damon_new_ctx();
int err;
if (!ctx)
return ERR_PTR(-ENOMEM);
err = damon_sysfs_apply_inputs(ctx, sys_ctx);
if (err) {
damon_destroy_ctx(ctx);
return ERR_PTR(err);
}
ctx->callback.after_wmarks_check = damon_sysfs_cmd_request_callback;
ctx->callback.after_aggregation = damon_sysfs_cmd_request_callback;
ctx->callback.before_terminate = damon_sysfs_before_terminate;
return ctx;
}
static int damon_sysfs_turn_damon_on(struct damon_sysfs_kdamond *kdamond)
{
struct damon_ctx *ctx;
int err;
if (damon_sysfs_kdamond_running(kdamond))
return -EBUSY;
if (damon_sysfs_cmd_request.kdamond == kdamond)
return -EBUSY;
/* TODO: support multiple contexts per kdamond */
if (kdamond->contexts->nr != 1)
return -EINVAL;
if (kdamond->damon_ctx)
damon_destroy_ctx(kdamond->damon_ctx);
kdamond->damon_ctx = NULL;
ctx = damon_sysfs_build_ctx(kdamond->contexts->contexts_arr[0]);
if (IS_ERR(ctx))
return PTR_ERR(ctx);
err = damon_start(&ctx, 1, false);
if (err) {
damon_destroy_ctx(ctx);
return err;
}
kdamond->damon_ctx = ctx;
return err;
}
static int damon_sysfs_turn_damon_off(struct damon_sysfs_kdamond *kdamond)
{
if (!kdamond->damon_ctx)
return -EINVAL;
return damon_stop(&kdamond->damon_ctx, 1);
/*
* To allow users show final monitoring results of already turned-off
* DAMON, we free kdamond->damon_ctx in next
* damon_sysfs_turn_damon_on(), or kdamonds_nr_store()
*/
}
/*
* damon_sysfs_handle_cmd() - Handle a command for a specific kdamond.
* @cmd: The command to handle.
* @kdamond: The kobject wrapper for the associated kdamond.
*
* This function handles a DAMON sysfs command for a kdamond. For commands
* that need to access running DAMON context-internal data, it requests
* handling of the command to the DAMON callback
* (@damon_sysfs_cmd_request_callback()) and wait until it is properly handled,
* or the context is completed.
*
* Return: 0 on success, negative error code otherwise.
*/
static int damon_sysfs_handle_cmd(enum damon_sysfs_cmd cmd,
struct damon_sysfs_kdamond *kdamond)
{
bool need_wait = true;
/* Handle commands that doesn't access DAMON context-internal data */
switch (cmd) {
case DAMON_SYSFS_CMD_ON:
return damon_sysfs_turn_damon_on(kdamond);
case DAMON_SYSFS_CMD_OFF:
return damon_sysfs_turn_damon_off(kdamond);
default:
break;
}
/* Pass the command to DAMON callback for safe DAMON context access */
if (damon_sysfs_cmd_request.kdamond)
return -EBUSY;
if (!damon_sysfs_kdamond_running(kdamond))
return -EINVAL;
damon_sysfs_cmd_request.cmd = cmd;
damon_sysfs_cmd_request.kdamond = kdamond;
/*
* wait until damon_sysfs_cmd_request_callback() handles the request
* from kdamond context
*/
mutex_unlock(&damon_sysfs_lock);
while (need_wait) {
schedule_timeout_idle(msecs_to_jiffies(100));
if (!mutex_trylock(&damon_sysfs_lock))
continue;
if (!damon_sysfs_cmd_request.kdamond) {
/* damon_sysfs_cmd_request_callback() handled */
need_wait = false;
} else if (!damon_sysfs_kdamond_running(kdamond)) {
/* kdamond has already finished */
need_wait = false;
damon_sysfs_cmd_request.kdamond = NULL;
}
mutex_unlock(&damon_sysfs_lock);
}
mutex_lock(&damon_sysfs_lock);
return 0;
}
static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
const char *buf, size_t count)
{
struct damon_sysfs_kdamond *kdamond = container_of(kobj,
struct damon_sysfs_kdamond, kobj);
enum damon_sysfs_cmd cmd;
ssize_t ret = -EINVAL;
if (!mutex_trylock(&damon_sysfs_lock))
return -EBUSY;
for (cmd = 0; cmd < NR_DAMON_SYSFS_CMDS; cmd++) {
if (sysfs_streq(buf, damon_sysfs_cmd_strs[cmd])) {
ret = damon_sysfs_handle_cmd(cmd, kdamond);
break;
}
}
mutex_unlock(&damon_sysfs_lock);
if (!ret)
ret = count;
return ret;
}
static ssize_t pid_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct damon_sysfs_kdamond *kdamond = container_of(kobj,
struct damon_sysfs_kdamond, kobj);
struct damon_ctx *ctx;
int pid = -1;
if (!mutex_trylock(&damon_sysfs_lock))
return -EBUSY;
ctx = kdamond->damon_ctx;
if (!ctx)
goto out;
mutex_lock(&ctx->kdamond_lock);
if (ctx->kdamond)
pid = ctx->kdamond->pid;
mutex_unlock(&ctx->kdamond_lock);
out:
mutex_unlock(&damon_sysfs_lock);
return sysfs_emit(buf, "%d\n", pid);
}
static void damon_sysfs_kdamond_release(struct kobject *kobj)
{
struct damon_sysfs_kdamond *kdamond = container_of(kobj,
struct damon_sysfs_kdamond, kobj);
if (kdamond->damon_ctx)
damon_destroy_ctx(kdamond->damon_ctx);
kfree(kdamond);
}
static struct kobj_attribute damon_sysfs_kdamond_state_attr =
__ATTR_RW_MODE(state, 0600);
static struct kobj_attribute damon_sysfs_kdamond_pid_attr =
__ATTR_RO_MODE(pid, 0400);
static struct attribute *damon_sysfs_kdamond_attrs[] = {
&damon_sysfs_kdamond_state_attr.attr,
&damon_sysfs_kdamond_pid_attr.attr,
NULL,
};
ATTRIBUTE_GROUPS(damon_sysfs_kdamond);
static struct kobj_type damon_sysfs_kdamond_ktype = {
.release = damon_sysfs_kdamond_release,
.sysfs_ops = &kobj_sysfs_ops,
.default_groups = damon_sysfs_kdamond_groups,
};
/*
* kdamonds directory
*/
struct damon_sysfs_kdamonds {
struct kobject kobj;
struct damon_sysfs_kdamond **kdamonds_arr;
int nr;
};
static struct damon_sysfs_kdamonds *damon_sysfs_kdamonds_alloc(void)
{
return kzalloc(sizeof(struct damon_sysfs_kdamonds), GFP_KERNEL);
}
static void damon_sysfs_kdamonds_rm_dirs(struct damon_sysfs_kdamonds *kdamonds)
{
struct damon_sysfs_kdamond **kdamonds_arr = kdamonds->kdamonds_arr;
int i;
for (i = 0; i < kdamonds->nr; i++) {
damon_sysfs_kdamond_rm_dirs(kdamonds_arr[i]);
kobject_put(&kdamonds_arr[i]->kobj);
}
kdamonds->nr = 0;
kfree(kdamonds_arr);
kdamonds->kdamonds_arr = NULL;
}
static bool damon_sysfs_kdamonds_busy(struct damon_sysfs_kdamond **kdamonds,
int nr_kdamonds)
{
int i;
for (i = 0; i < nr_kdamonds; i++) {
if (damon_sysfs_kdamond_running(kdamonds[i]) ||
damon_sysfs_cmd_request.kdamond == kdamonds[i])
return true;
}
return false;
}
static int damon_sysfs_kdamonds_add_dirs(struct damon_sysfs_kdamonds *kdamonds,
int nr_kdamonds)
{
struct damon_sysfs_kdamond **kdamonds_arr, *kdamond;
int err, i;
if (damon_sysfs_kdamonds_busy(kdamonds->kdamonds_arr, kdamonds->nr))
return -EBUSY;
damon_sysfs_kdamonds_rm_dirs(kdamonds);
if (!nr_kdamonds)
return 0;
kdamonds_arr = kmalloc_array(nr_kdamonds, sizeof(*kdamonds_arr),
GFP_KERNEL | __GFP_NOWARN);
if (!kdamonds_arr)
return -ENOMEM;
kdamonds->kdamonds_arr = kdamonds_arr;
for (i = 0; i < nr_kdamonds; i++) {
kdamond = damon_sysfs_kdamond_alloc();
if (!kdamond) {
damon_sysfs_kdamonds_rm_dirs(kdamonds);
return -ENOMEM;
}
err = kobject_init_and_add(&kdamond->kobj,
&damon_sysfs_kdamond_ktype, &kdamonds->kobj,
"%d", i);
if (err)
goto out;
err = damon_sysfs_kdamond_add_dirs(kdamond);
if (err)
goto out;
kdamonds_arr[i] = kdamond;
kdamonds->nr++;
}
return 0;
out:
damon_sysfs_kdamonds_rm_dirs(kdamonds);
kobject_put(&kdamond->kobj);
return err;
}
static ssize_t nr_kdamonds_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct damon_sysfs_kdamonds *kdamonds = container_of(kobj,
struct damon_sysfs_kdamonds, kobj);
return sysfs_emit(buf, "%d\n", kdamonds->nr);
}
static ssize_t nr_kdamonds_store(struct kobject *kobj,
struct kobj_attribute *attr, const char *buf, size_t count)
{
struct damon_sysfs_kdamonds *kdamonds;
int nr, err;
err = kstrtoint(buf, 0, &nr);
if (err)
return err;
if (nr < 0)
return -EINVAL;
kdamonds = container_of(kobj, struct damon_sysfs_kdamonds, kobj);
if (!mutex_trylock(&damon_sysfs_lock))
return -EBUSY;
err = damon_sysfs_kdamonds_add_dirs(kdamonds, nr);
mutex_unlock(&damon_sysfs_lock);
if (err)
return err;
return count;
}
static void damon_sysfs_kdamonds_release(struct kobject *kobj)
{
kfree(container_of(kobj, struct damon_sysfs_kdamonds, kobj));
}
static struct kobj_attribute damon_sysfs_kdamonds_nr_attr =
__ATTR_RW_MODE(nr_kdamonds, 0600);
static struct attribute *damon_sysfs_kdamonds_attrs[] = {
&damon_sysfs_kdamonds_nr_attr.attr,
NULL,
};
ATTRIBUTE_GROUPS(damon_sysfs_kdamonds);
static struct kobj_type damon_sysfs_kdamonds_ktype = {
.release = damon_sysfs_kdamonds_release,
.sysfs_ops = &kobj_sysfs_ops,
.default_groups = damon_sysfs_kdamonds_groups,
};
/*
* damon user interface directory
*/
struct damon_sysfs_ui_dir {
struct kobject kobj;
struct damon_sysfs_kdamonds *kdamonds;
};
static struct damon_sysfs_ui_dir *damon_sysfs_ui_dir_alloc(void)
{
return kzalloc(sizeof(struct damon_sysfs_ui_dir), GFP_KERNEL);
}
static int damon_sysfs_ui_dir_add_dirs(struct damon_sysfs_ui_dir *ui_dir)
{
struct damon_sysfs_kdamonds *kdamonds;
int err;
kdamonds = damon_sysfs_kdamonds_alloc();
if (!kdamonds)
return -ENOMEM;
err = kobject_init_and_add(&kdamonds->kobj,
&damon_sysfs_kdamonds_ktype, &ui_dir->kobj,
"kdamonds");
if (err) {
kobject_put(&kdamonds->kobj);
return err;
}
ui_dir->kdamonds = kdamonds;
return err;
}
static void damon_sysfs_ui_dir_release(struct kobject *kobj)
{
kfree(container_of(kobj, struct damon_sysfs_ui_dir, kobj));
}
static struct attribute *damon_sysfs_ui_dir_attrs[] = {
NULL,
};
ATTRIBUTE_GROUPS(damon_sysfs_ui_dir);
static struct kobj_type damon_sysfs_ui_dir_ktype = {
.release = damon_sysfs_ui_dir_release,
.sysfs_ops = &kobj_sysfs_ops,
.default_groups = damon_sysfs_ui_dir_groups,
};
static int __init damon_sysfs_init(void)
{
struct kobject *damon_sysfs_root;
struct damon_sysfs_ui_dir *admin;
int err;
damon_sysfs_root = kobject_create_and_add("damon", mm_kobj);
if (!damon_sysfs_root)
return -ENOMEM;
admin = damon_sysfs_ui_dir_alloc();
if (!admin) {
kobject_put(damon_sysfs_root);
return -ENOMEM;
}
err = kobject_init_and_add(&admin->kobj, &damon_sysfs_ui_dir_ktype,
damon_sysfs_root, "admin");
if (err)
goto out;
err = damon_sysfs_ui_dir_add_dirs(admin);
if (err)
goto out;
return 0;
out:
kobject_put(&admin->kobj);
kobject_put(damon_sysfs_root);
return err;
}
subsys_initcall(damon_sysfs_init);