To avoid interference between DAMON contexts monitoring overlapping memory regions, damon_start() works in an exclusive manner. That is, damon_start() does nothing bug fails if any context that started by another instance of the function is still running. This makes its usage a little bit restrictive. However, admins could aware each DAMON usage and address such interferences on their own in some cases.

This commit hence implements non-exclusive mode of the function and allows the callers to select the mode. Note that the exclusive groups and non-exclusive groups of contexts will respect each other in a manner similar to that of reader-writer locks. Therefore, this commit will not cause any behavioral change to the exclusive groups.

Signed-off-by: SeongJae Park sj@kernel.org --- include/linux/damon.h | 2 +- mm/damon/core.c | 23 +++++++++++++++-------- mm/damon/dbgfs.c | 2 +- mm/damon/reclaim.c | 2 +- 4 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/include/linux/damon.h b/include/linux/damon.h index 49c4a11ecf20..f8e99e47d747 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -508,7 +508,7 @@ int damon_nr_running_ctxs(void); int damon_register_ops(struct damon_operations *ops); int damon_select_ops(struct damon_ctx *ctx, enum damon_ops_id id);

-int damon_start(struct damon_ctx **ctxs, int nr_ctxs); +int damon_start(struct damon_ctx **ctxs, int nr_ctxs, bool exclusive); int damon_stop(struct damon_ctx **ctxs, int nr_ctxs);

#endif /* CONFIG_DAMON */ diff --git a/mm/damon/core.c b/mm/damon/core.c index 82e0a4620c4f..c1e0fed4e877 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -24,6 +24,7 @@

static DEFINE_MUTEX(damon_lock); static int nr_running_ctxs; +static bool running_exclusive_ctxs;

static DEFINE_MUTEX(damon_ops_lock); static struct damon_operations damon_registered_ops[NR_DAMON_OPS]; @@ -434,22 +435,25 @@ static int __damon_start(struct damon_ctx *ctx) * damon_start() - Starts the monitorings for a given group of contexts. * @ctxs: an array of the pointers for contexts to start monitoring * @nr_ctxs: size of @ctxs + * @exclusive: exclusiveness of this contexts group * * This function starts a group of monitoring threads for a group of monitoring * contexts. One thread per each context is created and run in parallel. The - * caller should handle synchronization between the threads by itself. If a - * group of threads that created by other 'damon_start()' call is currently - * running, this function does nothing but returns -EBUSY. + * caller should handle synchronization between the threads by itself. If + * @exclusive is true and a group of threads that created by other + * 'damon_start()' call is currently running, this function does nothing but + * returns -EBUSY. * * Return: 0 on success, negative error code otherwise. */ -int damon_start(struct damon_ctx **ctxs, int nr_ctxs) +int damon_start(struct damon_ctx **ctxs, int nr_ctxs, bool exclusive) { int i; int err = 0;

mutex_lock(&damon_lock); - if (nr_running_ctxs) { + if ((exclusive && nr_running_ctxs) || + (!exclusive && running_exclusive_ctxs)) { mutex_unlock(&damon_lock); return -EBUSY; } @@ -460,13 +464,15 @@ int damon_start(struct damon_ctx **ctxs, int nr_ctxs) break; nr_running_ctxs++; } + if (exclusive && nr_running_ctxs) + running_exclusive_ctxs = true; mutex_unlock(&damon_lock);

return err; }

/* - * __damon_stop() - Stops monitoring of given context. + * __damon_stop() - Stops monitoring of a given context. * @ctx: monitoring context * * Return: 0 on success, negative error code otherwise. @@ -504,9 +510,8 @@ int damon_stop(struct damon_ctx **ctxs, int nr_ctxs) /* nr_running_ctxs is decremented in kdamond_fn */ err = __damon_stop(ctxs[i]); if (err) - return err; + break; } - return err; }

@@ -1102,6 +1107,8 @@ static int kdamond_fn(void *data)

mutex_lock(&damon_lock); nr_running_ctxs--; + if (!nr_running_ctxs && running_exclusive_ctxs) + running_exclusive_ctxs = false; mutex_unlock(&damon_lock);

return 0; diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c index 05b574cbcea8..a0dab8b5e45f 100644 --- a/mm/damon/dbgfs.c +++ b/mm/damon/dbgfs.c @@ -967,7 +967,7 @@ static ssize_t dbgfs_monitor_on_write(struct file *file, return -EINVAL; } } - ret = damon_start(dbgfs_ctxs, dbgfs_nr_ctxs); + ret = damon_start(dbgfs_ctxs, dbgfs_nr_ctxs, true); } else if (!strncmp(kbuf, "off", count)) { ret = damon_stop(dbgfs_ctxs, dbgfs_nr_ctxs); } else { diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c index b53d9c22fad1..e34c4d0c4d93 100644 --- a/mm/damon/reclaim.c +++ b/mm/damon/reclaim.c @@ -330,7 +330,7 @@ static int damon_reclaim_turn(bool on) if (err) goto free_scheme_out;

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

DAMON's debugfs-based user interface served very well, so far. However, it unnecessarily depends on debugfs, while DAMON is not aimed to be used for only debugging. Also, the interface receives multiple values via one file. For example, schemes file receives 18 values separated by white spaces. As a result, it is ineffient, hard to be used, and difficult to be extended. Especially, keeping backward compatibility of user space tools is getting only challenging. It would be better to implement another reliable and flexible interface and deprecate the debugfs interface in long term.

To this end, this commit implements a stub of a part of the new user interface of DAMON using sysfs. Specifically, this commit implements the sysfs control parts for virtual address space monitoring.

More specifically, the idea of the new interface is, using directory hierarchies and making one file for one value. The hierarchy that this commit is introducing is as below. In the below figure, parents-children relations are represented with indentations, each directory is having ``/`` suffix, and files in each directory are separated by comma (",").

/sys/kernel/mm/damon/admin │ kdamonds/nr_kdamonds │ │ 0/state,pid │ │ │ contexts/nr_contexts │ │ │ │ 0/operations │ │ │ │ │ monitoring_attrs/ │ │ │ │ │ │ intervals/sample_us,aggr_us,update_us │ │ │ │ │ │ nr_regions/min,max │ │ │ │ │ targets/nr_targets │ │ │ │ │ │ 0/pid_target │ │ │ │ │ │ ... │ │ │ │ ... │ │ ...

Writing a number <N> to each 'nr' file makes directories of name <0> to <N-1> in the directory of the 'nr' file. That's all this commit does. Writing proper values to relevant files will construct the DAMON contexts, and writing a special keyword, 'on', to 'state' files for each kdamond will ask DAMON to start the constructed contexts.

For a short example, using below commands for monitoring virtual address spaces of a given workload is imaginable:

# cd /sys/kernel/mm/damon/admin/ # echo 1 > kdamonds/nr_kdamonds # echo 1 > kdamonds/0/contexts/nr_contexts # echo vaddr > kdamonds/0/contexts/0/operations # echo 1 > kdamonds/0/contexts/0/targets/nr_targets # echo $(pidof <workload>) > kdamonds/0/contexts/0/targets/0/pid_target # echo on > kdamonds/0/state

Please note that this commit is implementing only the sysfs part stub as abovely mentioned. This commit doesn't implement the special keywords for 'state' files. Following commits will do that.

Signed-off-by: SeongJae Park sj@kernel.org --- mm/damon/Kconfig | 7 + mm/damon/Makefile | 1 + mm/damon/sysfs.c | 1082 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 1090 insertions(+) create mode 100644 mm/damon/sysfs.c

diff --git a/mm/damon/Kconfig b/mm/damon/Kconfig index 01bad77ad7ae..9b559c76d6dd 100644 --- a/mm/damon/Kconfig +++ b/mm/damon/Kconfig @@ -52,6 +52,13 @@ config DAMON_VADDR_KUNIT_TEST

If unsure, say N.

+config DAMON_SYSFS + bool "DAMON sysfs interface" + depends on DAMON && SYSFS + help + This builds the sysfs interface for DAMON. The user space can use + the interface for arbitrary data access monitoring. + config DAMON_DBGFS bool "DAMON debugfs interface" depends on DAMON_VADDR && DAMON_PADDR && DEBUG_FS diff --git a/mm/damon/Makefile b/mm/damon/Makefile index aebbf6c14c51..dbf7190b4144 100644 --- a/mm/damon/Makefile +++ b/mm/damon/Makefile @@ -3,5 +3,6 @@ obj-y := core.o obj-$(CONFIG_DAMON_VADDR) += ops-common.o vaddr.o obj-$(CONFIG_DAMON_PADDR) += ops-common.o paddr.o +obj-$(CONFIG_DAMON_SYSFS) += sysfs.o obj-$(CONFIG_DAMON_DBGFS) += dbgfs.o obj-$(CONFIG_DAMON_RECLAIM) += reclaim.o diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c new file mode 100644 index 000000000000..87cf28ae6a6f --- /dev/null +++ b/mm/damon/sysfs.c @@ -0,0 +1,1082 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DAMON sysfs Interface + * + * Copyright (c) 2022 SeongJae Park sj@kernel.org + */ + +#include <linux/damon.h> +#include <linux/kobject.h> +#include <linux/pid.h> +#include <linux/sched.h> +#include <linux/slab.h> + +static DEFINE_MUTEX(damon_sysfs_lock); + +/* + * unsigned long range directory + */ + +struct damon_sysfs_ul_range { + struct kobject kobj; + unsigned long min; + unsigned long max; +}; + +static struct damon_sysfs_ul_range *damon_sysfs_ul_range_alloc( + unsigned long min, + unsigned long max) +{ + struct damon_sysfs_ul_range *range = kmalloc(sizeof(*range), + GFP_KERNEL); + + if (!range) + return NULL; + range->kobj = (struct kobject){}; + range->min = min; + range->max = max; + + return range; +} + +static ssize_t min_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_ul_range *range = container_of(kobj, + struct damon_sysfs_ul_range, kobj); + + return sysfs_emit(buf, "%lu\n", range->min); +} + +static ssize_t min_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_ul_range *range = container_of(kobj, + struct damon_sysfs_ul_range, kobj); + unsigned long min; + int err; + + err = kstrtoul(buf, 0, &min); + if (err) + return -EINVAL; + + range->min = min; + return count; +} + +static ssize_t max_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_ul_range *range = container_of(kobj, + struct damon_sysfs_ul_range, kobj); + + return sysfs_emit(buf, "%lu\n", range->max); +} + +static ssize_t max_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_ul_range *range = container_of(kobj, + struct damon_sysfs_ul_range, kobj); + unsigned long max; + int err; + + err = kstrtoul(buf, 0, &max); + if (err) + return -EINVAL; + + range->max = max; + return count; +} + +static void damon_sysfs_ul_range_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_ul_range, kobj)); +} + +static struct kobj_attribute damon_sysfs_ul_range_min_attr = + __ATTR_RW_MODE(min, 0600); + +static struct kobj_attribute damon_sysfs_ul_range_max_attr = + __ATTR_RW_MODE(max, 0600); + +static struct attribute *damon_sysfs_ul_range_attrs[] = { + &damon_sysfs_ul_range_min_attr.attr, + &damon_sysfs_ul_range_max_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_ul_range); + +static struct kobj_type damon_sysfs_ul_range_ktype = { + .release = damon_sysfs_ul_range_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_ul_range_groups, +}; + +/* + * target directory + */ + +struct damon_sysfs_target { + struct kobject kobj; + int pid; +}; + +static struct damon_sysfs_target *damon_sysfs_target_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_target), GFP_KERNEL); +} + +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++) + 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; + + 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 = container_of(kobj, + struct damon_sysfs_targets, kobj); + int nr, err = kstrtoint(buf, 0, &nr); + + if (err) + return err; + if (nr < 0) + return -EINVAL; + + 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 -EINVAL; + + 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 -EINVAL; + + 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 -EINVAL; + + 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) + 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", + "paddr", +}; + +struct damon_sysfs_context { + struct kobject kobj; + enum damon_ops_id ops_id; + struct damon_sysfs_attrs *attrs; + struct damon_sysfs_targets *targets; +}; + +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_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; + return 0; + +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); +} + +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])) { + /* Support only vaddr */ + if (id != DAMON_OPS_VADDR) + return -EINVAL; + 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_operations_attr = + __ATTR_RW_MODE(operations, 0600); + +static struct attribute *damon_sysfs_context_attrs[] = { + &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 = container_of(kobj, + struct damon_sysfs_contexts, kobj); + 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; + + 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 ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + return -EINVAL; +} + +static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + return -EINVAL; +} + +static ssize_t pid_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return -EINVAL; +} + +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(container_of(kobj, struct damon_sysfs_kdamond, kobj)); +} + +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 int damon_sysfs_nr_running_ctxs(struct damon_sysfs_kdamond **kdamonds, + int nr_kdamonds) +{ + int nr_running_ctxs = 0; + int i; + + for (i = 0; i < nr_kdamonds; i++) { + struct damon_ctx *ctx = kdamonds[i]->damon_ctx; + + if (!ctx) + continue; + mutex_lock(&ctx->kdamond_lock); + if (ctx->kdamond) + nr_running_ctxs++; + mutex_unlock(&ctx->kdamond_lock); + } + return nr_running_ctxs; +} + +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_nr_running_ctxs(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 = container_of(kobj, + struct damon_sysfs_kdamonds, kobj); + int nr, err; + + err = kstrtoint(buf, 0, &nr); + if (err) + return err; + if (nr < 0) + return -EINVAL; + + 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);

This commit makes DAMON sysfs interface supports the physical address space monitoring. Specifically, this commit adds support of the initial monitoring regions set feature by adding 'regions' directory under each target directory and makes context operations file to receive 'paddr' in addition to 'vaddr'.

As a result, the files hierarchy becomes as below:

/sys/kernel/mm/damon/admin │ kdamonds/nr_kdamonds │ │ 0/state,pid │ │ │ contexts/nr_contexts │ │ │ │ 0/operations │ │ │ │ │ monitoring_attrs/ │ │ │ │ │ │ intervals/sample_us,aggr_us,update_us │ │ │ │ │ │ nr_regions/min,max │ │ │ │ │ targets/nr_targets │ │ │ │ │ │ 0/pid_target │ │ │ │ │ │ │ regions/nr_regions <- NEW DIRECTORY │ │ │ │ │ │ │ │ 0/start,end │ │ │ │ │ │ │ │ ... │ │ │ │ │ │ ... │ │ │ │ ... │ │ ...

Signed-off-by: SeongJae Park sj@kernel.org --- mm/damon/sysfs.c | 276 ++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 271 insertions(+), 5 deletions(-)

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index 9221c93db6cc..968a4ba8e81b 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -113,12 +113,220 @@ static struct kobj_type damon_sysfs_ul_range_ktype = { .default_groups = damon_sysfs_ul_range_groups, };

+/* + * init region directory + */ + +struct damon_sysfs_region { + struct kobject kobj; + unsigned long start; + unsigned long end; +}; + +static struct damon_sysfs_region *damon_sysfs_region_alloc( + unsigned long start, + unsigned long end) +{ + struct damon_sysfs_region *region = kmalloc(sizeof(*region), + GFP_KERNEL); + + if (!region) + return NULL; + region->kobj = (struct kobject){}; + region->start = start; + region->end = end; + return region; +} + +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->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->start); + + if (err) + return -EINVAL; + return 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->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->end); + + if (err) + return -EINVAL; + return 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(0, 0); + 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 = container_of(kobj, + struct damon_sysfs_regions, kobj); + int nr, err = kstrtoint(buf, 0, &nr); + + if (err) + return err; + if (nr < 0) + return -EINVAL; + + 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; };

@@ -127,6 +335,29 @@ 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) { @@ -188,8 +419,10 @@ 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++) + 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; @@ -224,6 +457,10 @@ static int damon_sysfs_targets_add_dirs(struct damon_sysfs_targets *targets, if (err) goto out;

+ err = damon_sysfs_target_add_dirs(target); + if (err) + goto out; + targets_arr[i] = target; targets->nr++; } @@ -608,9 +845,6 @@ static ssize_t operations_store(struct kobject *kobj,

for (id = 0; id < NR_DAMON_OPS; id++) { if (sysfs_streq(buf, damon_sysfs_ops_strs[id])) { - /* Support only vaddr */ - if (id != DAMON_OPS_VADDR) - return -EINVAL; context->ops_id = id; return count; } @@ -855,10 +1089,37 @@ static void damon_sysfs_destroy_targets(struct damon_ctx *ctx) } }

+static int damon_sysfs_set_regions(struct damon_target *t, + struct damon_sysfs_regions *sysfs_regions) +{ + int i; + + for (i = 0; i < sysfs_regions->nr; i++) { + struct damon_sysfs_region *sys_region = + sysfs_regions->regions_arr[i]; + struct damon_region *prev, *r; + + if (sys_region->start > sys_region->end) + return -EINVAL; + r = damon_new_region(sys_region->start, sys_region->end); + if (!r) + return -ENOMEM; + damon_add_region(r, t); + if (damon_nr_regions(t) > 1) { + prev = damon_prev_region(r); + if (prev->ar.end > r->ar.start) { + damon_destroy_region(r, t); + return -EINVAL; + } + } + } + return 0; +} + static int damon_sysfs_set_targets(struct damon_ctx *ctx, struct damon_sysfs_targets *sysfs_targets) { - int i; + int i, err;

for (i = 0; i < sysfs_targets->nr; i++) { struct damon_sysfs_target *sys_target = @@ -877,6 +1138,11 @@ static int damon_sysfs_set_targets(struct damon_ctx *ctx, } } damon_add_target(ctx, t); + err = damon_sysfs_set_regions(t, sys_target->regions); + if (err) { + damon_sysfs_destroy_targets(ctx); + return err; + } } return 0; }

This commit makes DAMON sysfs interface supports the DAMOS quotas feature. Specifically, this commit adds 'quotas' directory under each scheme directory and makes kdamond 'state' file writing respects the contents in the directory.

As a result, the files hierarchy becomes as below:

/sys/kernel/mm/damon/admin │ kdamonds/nr_kdamonds │ │ 0/state,pid │ │ │ contexts/nr_contexts │ │ │ │ 0/operations │ │ │ │ │ monitoring_attrs/intervals/sample_us,aggr_us,update_us │ │ │ │ │ │ nr_regions/min,max │ │ │ │ │ targets/nr_targets │ │ │ │ │ │ 0/pid_target │ │ │ │ │ │ │ regions/nr_regions │ │ │ │ │ │ │ │ 0/start,end │ │ │ │ │ │ │ │ ... │ │ │ │ │ │ ... │ │ │ │ │ schemes/nr_schemes │ │ │ │ │ │ 0/action │ │ │ │ │ │ │ access_pattern/ │ │ │ │ │ │ │ │ sz/min,max │ │ │ │ │ │ │ │ nr_accesses/min,max │ │ │ │ │ │ │ │ age/min,max │ │ │ │ │ │ │ quotas/ms,bytes,reset_interval_ms <- NEW DIRECTORY │ │ │ │ │ │ ... │ │ │ │ ... │ │ ...

Signed-off-by: SeongJae Park sj@kernel.org --- mm/damon/sysfs.c | 146 ++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 145 insertions(+), 1 deletion(-)

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index 4f593f0bf16c..36540bdf6442 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -113,6 +113,113 @@ static struct kobj_type damon_sysfs_ul_range_ktype = { .default_groups = damon_sysfs_ul_range_groups, };

+/* + * quotas directory + */ + +struct damon_sysfs_quotas { + struct kobject kobj; + unsigned long ms; + unsigned long sz; + unsigned long reset_interval_ms; +}; + +static struct damon_sysfs_quotas *damon_sysfs_quotas_alloc(void) +{ + return kzalloc(sizeof(struct damon_sysfs_quotas), GFP_KERNEL); +} + +static ssize_t ms_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_quotas *quotas = container_of(kobj, + struct damon_sysfs_quotas, kobj); + + return sysfs_emit(buf, "%lu\n", quotas->ms); +} + +static ssize_t ms_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_quotas *quotas = container_of(kobj, + struct damon_sysfs_quotas, kobj); + int err = kstrtoul(buf, 0, &quotas->ms); + + if (err) + return -EINVAL; + return count; +} + +static ssize_t bytes_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_quotas *quotas = container_of(kobj, + struct damon_sysfs_quotas, kobj); + + return sysfs_emit(buf, "%lu\n", quotas->sz); +} + +static ssize_t bytes_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_quotas *quotas = container_of(kobj, + struct damon_sysfs_quotas, kobj); + int err = kstrtoul(buf, 0, &quotas->sz); + + if (err) + return -EINVAL; + return count; +} + +static ssize_t reset_interval_ms_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_quotas *quotas = container_of(kobj, + struct damon_sysfs_quotas, kobj); + + return sysfs_emit(buf, "%lu\n", quotas->reset_interval_ms); +} + +static ssize_t reset_interval_ms_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_quotas *quotas = container_of(kobj, + struct damon_sysfs_quotas, kobj); + int err = kstrtoul(buf, 0, &quotas->reset_interval_ms); + + if (err) + return -EINVAL; + return count; +} + +static void damon_sysfs_quotas_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_quotas, kobj)); +} + +static struct kobj_attribute damon_sysfs_quotas_ms_attr = + __ATTR_RW_MODE(ms, 0600); + +static struct kobj_attribute damon_sysfs_quotas_sz_attr = + __ATTR_RW_MODE(bytes, 0600); + +static struct kobj_attribute damon_sysfs_quotas_reset_interval_ms_attr = + __ATTR_RW_MODE(reset_interval_ms, 0600); + +static struct attribute *damon_sysfs_quotas_attrs[] = { + &damon_sysfs_quotas_ms_attr.attr, + &damon_sysfs_quotas_sz_attr.attr, + &damon_sysfs_quotas_reset_interval_ms_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_quotas); + +static struct kobj_type damon_sysfs_quotas_ktype = { + .release = damon_sysfs_quotas_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_quotas_groups, +}; + /* * access_pattern directory */ @@ -220,6 +327,7 @@ struct damon_sysfs_scheme { struct kobject kobj; enum damos_action action; struct damon_sysfs_access_pattern *access_pattern; + struct damon_sysfs_quotas *quotas; };

/* This should match with enum damos_action */ @@ -270,6 +378,25 @@ static int damon_sysfs_scheme_set_access_pattern( return err; }

+static int damon_sysfs_scheme_set_quotas(struct damon_sysfs_scheme *scheme) +{ + struct damon_sysfs_quotas *quotas = damon_sysfs_quotas_alloc(); + int err; + + if (!quotas) + return -ENOMEM; + err = kobject_init_and_add(&quotas->kobj, &damon_sysfs_quotas_ktype, + &scheme->kobj, "quotas"); + if (err) + goto out; + scheme->quotas = quotas; + return 0; + +out: + kobject_put(&quotas->kobj); + return err; +} + static int damon_sysfs_scheme_add_dirs(struct damon_sysfs_scheme *scheme) { int err; @@ -277,13 +404,22 @@ static int damon_sysfs_scheme_add_dirs(struct damon_sysfs_scheme *scheme) err = damon_sysfs_scheme_set_access_pattern(scheme); if (err) return err; + err = damon_sysfs_scheme_set_quotas(scheme); + if (err) + goto put_access_pattern_out; return 0; + +put_access_pattern_out: + kobject_put(&scheme->access_pattern->kobj); + scheme->access_pattern = NULL; + return err; }

static void damon_sysfs_scheme_rm_dirs(struct damon_sysfs_scheme *scheme) { damon_sysfs_access_pattern_rm_dirs(scheme->access_pattern); kobject_put(&scheme->access_pattern->kobj); + kobject_put(&scheme->quotas->kobj); }

static ssize_t action_show(struct kobject *kobj, struct kobj_attribute *attr, @@ -1520,7 +1656,15 @@ static struct damos *damon_sysfs_mk_scheme( { struct damon_sysfs_access_pattern *pattern = sysfs_scheme->access_pattern; - struct damos_quota quota = (struct damos_quota){}; + struct damon_sysfs_quotas *sysfs_quotas = sysfs_scheme->quotas; + struct damos_quota quota = { + .ms = sysfs_quotas->ms, + .sz = sysfs_quotas->sz, + .reset_interval = sysfs_quotas->reset_interval_ms, + .weight_sz = 1000, + .weight_nr_accesses = 1000, + .weight_age = 1000, + }; struct damos_watermarks wmarks = { .metric = DAMOS_WMARK_NONE, .interval = 0,

This commit makes DAMON sysfs interface supports the DAMOS watermarks feature. Specifically, this commit adds 'watermarks' directory under each scheme directory and makes kdamond 'state' file writing respects the contents in the directory.

As a result, the files hierarchy becomes as below:

/sys/kernel/mm/damon/admin │ kdamonds/nr_kdamonds │ │ 0/state,pid │ │ │ contexts/nr_contexts │ │ │ │ 0/operations │ │ │ │ │ monitoring_attrs/intervals/sample_us,aggr_us,update_us │ │ │ │ │ │ nr_regions/min,max │ │ │ │ │ targets/nr_targets │ │ │ │ │ │ 0/pid_target │ │ │ │ │ │ │ regions/nr_regions │ │ │ │ │ │ │ │ 0/start,end │ │ │ │ │ │ │ │ ... │ │ │ │ │ │ ... │ │ │ │ │ schemes/nr_schemes │ │ │ │ │ │ 0/action │ │ │ │ │ │ │ access_pattern/ │ │ │ │ │ │ │ │ sz/min,max │ │ │ │ │ │ │ │ nr_accesses/min,max │ │ │ │ │ │ │ │ age/min,max │ │ │ │ │ │ │ quotas/ms,sz,reset_interval_ms │ │ │ │ │ │ │ │ weights/sz_permil,nr_accesses_permil,age_permil │ │ │ │ │ │ │ watermarks/ <- NEW DIRECTORY │ │ │ │ │ │ │ │ metric,interval_us,high,mid,lo │ │ │ │ │ │ ... │ │ │ │ ... │ │ ...

Signed-off-by: SeongJae Park sj@kernel.org --- mm/damon/sysfs.c | 220 +++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 215 insertions(+), 5 deletions(-)

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index fb1c39eabc31..2e09ed36f666 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -113,6 +113,189 @@ static struct kobj_type damon_sysfs_ul_range_ktype = { .default_groups = damon_sysfs_ul_range_groups, };

+/* + * watermarks directory + */ + +struct damon_sysfs_watermarks { + struct kobject kobj; + enum damos_wmark_metric metric; + unsigned long interval_us; + unsigned long high; + unsigned long mid; + unsigned long low; +}; + +static struct damon_sysfs_watermarks *damon_sysfs_watermarks_alloc( + enum damos_wmark_metric metric, unsigned long interval_us, + unsigned long high, unsigned long mid, unsigned long low) +{ + struct damon_sysfs_watermarks *watermarks = kmalloc( + sizeof(*watermarks), GFP_KERNEL); + + if (!watermarks) + return NULL; + watermarks->kobj = (struct kobject){}; + watermarks->metric = metric; + watermarks->interval_us = interval_us; + watermarks->high = high; + watermarks->mid = mid; + watermarks->low = low; + return watermarks; +} + +/* Should match with enum damos_wmark_metric */ +static const char * const damon_sysfs_wmark_metric_strs[] = { + "none", + "free_mem_rate", +}; + +static ssize_t metric_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + + return sysfs_emit(buf, "%s\n", + damon_sysfs_wmark_metric_strs[watermarks->metric]); +} + +static ssize_t metric_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + enum damos_wmark_metric metric; + + for (metric = 0; metric <= NR_DAMOS_WMARK_METRICS; metric++) { + if (sysfs_streq(buf, damon_sysfs_wmark_metric_strs[metric])) { + watermarks->metric = metric; + return count; + } + } + return -EINVAL; +} + +static ssize_t interval_us_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + + return sysfs_emit(buf, "%lu\n", watermarks->interval_us); +} + +static ssize_t interval_us_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + int err = kstrtoul(buf, 0, &watermarks->interval_us); + + if (err) + return -EINVAL; + return count; +} + +static ssize_t high_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + + return sysfs_emit(buf, "%lu\n", watermarks->high); +} + +static ssize_t high_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + int err = kstrtoul(buf, 0, &watermarks->high); + + if (err) + return -EINVAL; + return count; +} + +static ssize_t mid_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + + return sysfs_emit(buf, "%lu\n", watermarks->mid); +} + +static ssize_t mid_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + int err = kstrtoul(buf, 0, &watermarks->mid); + + if (err) + return -EINVAL; + return count; +} + +static ssize_t low_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + + return sysfs_emit(buf, "%lu\n", watermarks->low); +} + +static ssize_t low_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_watermarks *watermarks = container_of(kobj, + struct damon_sysfs_watermarks, kobj); + int err = kstrtoul(buf, 0, &watermarks->low); + + if (err) + return -EINVAL; + return count; +} + +static void damon_sysfs_watermarks_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_watermarks, kobj)); +} + +static struct kobj_attribute damon_sysfs_watermarks_metric_attr = + __ATTR_RW_MODE(metric, 0600); + +static struct kobj_attribute damon_sysfs_watermarks_interval_us_attr = + __ATTR_RW_MODE(interval_us, 0600); + +static struct kobj_attribute damon_sysfs_watermarks_high_attr = + __ATTR_RW_MODE(high, 0600); + +static struct kobj_attribute damon_sysfs_watermarks_mid_attr = + __ATTR_RW_MODE(mid, 0600); + +static struct kobj_attribute damon_sysfs_watermarks_low_attr = + __ATTR_RW_MODE(low, 0600); + +static struct attribute *damon_sysfs_watermarks_attrs[] = { + &damon_sysfs_watermarks_metric_attr.attr, + &damon_sysfs_watermarks_interval_us_attr.attr, + &damon_sysfs_watermarks_high_attr.attr, + &damon_sysfs_watermarks_mid_attr.attr, + &damon_sysfs_watermarks_low_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_watermarks); + +static struct kobj_type damon_sysfs_watermarks_ktype = { + .release = damon_sysfs_watermarks_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_watermarks_groups, +}; + /* * scheme/weights directory */ @@ -469,6 +652,7 @@ struct damon_sysfs_scheme { enum damos_action action; struct damon_sysfs_access_pattern *access_pattern; struct damon_sysfs_quotas *quotas; + struct damon_sysfs_watermarks *watermarks; };

/* This should match with enum damos_action */ @@ -541,6 +725,24 @@ static int damon_sysfs_scheme_set_quotas(struct damon_sysfs_scheme *scheme) return err; }

+static int damon_sysfs_scheme_set_watermarks(struct damon_sysfs_scheme *scheme) +{ + struct damon_sysfs_watermarks *watermarks = + damon_sysfs_watermarks_alloc(DAMOS_WMARK_NONE, 0, 0, 0, 0); + int err; + + if (!watermarks) + return -ENOMEM; + err = kobject_init_and_add(&watermarks->kobj, + &damon_sysfs_watermarks_ktype, &scheme->kobj, + "watermarks"); + if (err) + kobject_put(&watermarks->kobj); + else + scheme->watermarks = watermarks; + return err; +} + static int damon_sysfs_scheme_add_dirs(struct damon_sysfs_scheme *scheme) { int err; @@ -551,8 +753,14 @@ static int damon_sysfs_scheme_add_dirs(struct damon_sysfs_scheme *scheme) err = damon_sysfs_scheme_set_quotas(scheme); if (err) goto put_access_pattern_out; + err = damon_sysfs_scheme_set_watermarks(scheme); + if (err) + goto put_quotas_access_pattern_out; return 0;

+put_quotas_access_pattern_out: + kobject_put(&scheme->quotas->kobj); + scheme->quotas = NULL; put_access_pattern_out: kobject_put(&scheme->access_pattern->kobj); scheme->access_pattern = NULL; @@ -565,6 +773,7 @@ static void damon_sysfs_scheme_rm_dirs(struct damon_sysfs_scheme *scheme) kobject_put(&scheme->access_pattern->kobj); damon_sysfs_quotas_rm_dirs(scheme->quotas); kobject_put(&scheme->quotas->kobj); + kobject_put(&scheme->watermarks->kobj); }

static ssize_t action_show(struct kobject *kobj, struct kobj_attribute *attr, @@ -1803,6 +2012,7 @@ static struct damos *damon_sysfs_mk_scheme( sysfs_scheme->access_pattern; struct damon_sysfs_quotas *sysfs_quotas = sysfs_scheme->quotas; struct damon_sysfs_weights *sysfs_weights = sysfs_quotas->weights; + struct damon_sysfs_watermarks *sysfs_wmarks = sysfs_scheme->watermarks; struct damos_quota quota = { .ms = sysfs_quotas->ms, .sz = sysfs_quotas->sz, @@ -1812,11 +2022,11 @@ static struct damos *damon_sysfs_mk_scheme( .weight_age = sysfs_weights->age, }; struct damos_watermarks wmarks = { - .metric = DAMOS_WMARK_NONE, - .interval = 0, - .high = 0, - .mid = 0, - .low = 0, + .metric = sysfs_wmarks->metric, + .interval = sysfs_wmarks->interval_us, + .high = sysfs_wmarks->high, + .mid = sysfs_wmarks->mid, + .low = sysfs_wmarks->low, };

return damon_new_scheme(pattern->sz->min, pattern->sz->max,

This commit adds a selftest for DAMON sysfs interface. It tests the functionality of 'nr' files and existence of files in each directory of the hierarchy.

Signed-off-by: SeongJae Park sj@kernel.org --- tools/testing/selftests/damon/Makefile | 1 + tools/testing/selftests/damon/sysfs.sh | 306 +++++++++++++++++++++++++ 2 files changed, 307 insertions(+) create mode 100755 tools/testing/selftests/damon/sysfs.sh

diff --git a/tools/testing/selftests/damon/Makefile b/tools/testing/selftests/damon/Makefile index 937d36ae9a69..0470c5f3e690 100644 --- a/tools/testing/selftests/damon/Makefile +++ b/tools/testing/selftests/damon/Makefile @@ -6,5 +6,6 @@ TEST_GEN_FILES += huge_count_read_write TEST_FILES = _chk_dependency.sh _debugfs_common.sh TEST_PROGS = debugfs_attrs.sh debugfs_schemes.sh debugfs_target_ids.sh TEST_PROGS += debugfs_empty_targets.sh debugfs_huge_count_read_write.sh +TEST_PROGS += sysfs.sh

include ../lib.mk diff --git a/tools/testing/selftests/damon/sysfs.sh b/tools/testing/selftests/damon/sysfs.sh new file mode 100755 index 000000000000..2e3ae77cb6db --- /dev/null +++ b/tools/testing/selftests/damon/sysfs.sh @@ -0,0 +1,306 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 + +# Kselftest frmework requirement - SKIP code is 4. +ksft_skip=4 + +ensure_write_succ() +{ + file=$1 + content=$2 + reason=$3 + + if ! echo "$content" > "$file" + then + echo "writing $content to $file failed" + echo "expected success because $reason" + exit 1 + fi +} + +ensure_write_fail() +{ + file=$1 + content=$2 + reason=$3 + + if echo "$content" > "$file" + then + echo "writing $content to $file succeed ($fail_reason)" + echo "expected failure because $reason" + exit 1 + fi +} + +ensure_dir() +{ + dir=$1 + to_ensure=$2 + if [ "$to_ensure" = "exist" ] && [ ! -d "$dir" ] + then + echo "$dir dir is expected but not found" + exit 1 + elif [ "$to_ensure" = "not_exist" ] && [ -d "$dir" ] + then + echo "$dir dir is not expected but found" + exit 1 + fi +} + +ensure_file() +{ + file=$1 + to_ensure=$2 + permission=$3 + if [ "$to_ensure" = "exist" ] + then + if [ ! -f "$file" ] + then + echo "$file is expected but not found" + exit 1 + fi + perm=$(stat -c "%a" "$file") + if [ ! "$perm" = "$permission" ] + then + echo "$file permission: expected $permission but $perm" + exit 1 + fi + elif [ "$to_ensure" = "not_exist" ] && [ -f "$dir" ] + then + echo "$file is not expected but found" + exit 1 + fi +} + +test_range() +{ + range_dir=$1 + ensure_dir "$range_dir" "exist" + ensure_file "$range_dir/min" "exist" 600 + ensure_file "$range_dir/max" "exist" 600 +} + +test_stats() +{ + stats_dir=$1 + ensure_dir "$stats_dir" "exist" + for f in nr_tried sz_tried nr_applied sz_applied qt_exceeds + do + ensure_file "$stats_dir/$f" "exist" "400" + done +} + +test_watermarks() +{ + watermarks_dir=$1 + ensure_dir "$watermarks_dir" "exist" + ensure_file "$watermarks_dir/metric" "exist" "600" + ensure_file "$watermarks_dir/interval_us" "exist" "600" + ensure_file "$watermarks_dir/high" "exist" "600" + ensure_file "$watermarks_dir/mid" "exist" "600" + ensure_file "$watermarks_dir/low" "exist" "600" +} + +test_weights() +{ + weights_dir=$1 + ensure_dir "$weights_dir" "exist" + ensure_file "$weights_dir/sz_permil" "exist" "600" + ensure_file "$weights_dir/nr_accesses_permil" "exist" "600" + ensure_file "$weights_dir/age_permil" "exist" "600" +} + +test_quotas() +{ + quotas_dir=$1 + ensure_dir "$quotas_dir" "exist" + ensure_file "$quotas_dir/ms" "exist" 600 + ensure_file "$quotas_dir/bytes" "exist" 600 + ensure_file "$quotas_dir/reset_interval_ms" "exist" 600 + test_weights "$quotas_dir/weights" +} + +test_access_pattern() +{ + access_pattern_dir=$1 + ensure_dir "$access_pattern_dir" "exist" + test_range "$access_pattern_dir/age" + test_range "$access_pattern_dir/nr_accesses" + test_range "$access_pattern_dir/sz" +} + +test_scheme() +{ + scheme_dir=$1 + ensure_dir "$scheme_dir" "exist" + ensure_file "$scheme_dir/action" "exist" "600" + test_access_pattern "$scheme_dir/access_pattern" + test_quotas "$scheme_dir/quotas" + test_watermarks "$scheme_dir/watermarks" + test_stats "$scheme_dir/stats" +} + +test_schemes() +{ + schemes_dir=$1 + ensure_dir "$schemes_dir" "exist" + ensure_file "$schemes_dir/nr_schemes" "exist" 600 + + ensure_write_succ "$schemes_dir/nr_schemes" "1" "valid input" + test_scheme "$schemes_dir/0" + + ensure_write_succ "$schemes_dir/nr_schemes" "2" "valid input" + test_scheme "$schemes_dir/0" + test_scheme "$schemes_dir/1" + + ensure_write_succ "$schemes_dir/nr_schemes" "0" "valid input" + ensure_dir "$schemes_dir/0" "not_exist" + ensure_dir "$schemes_dir/1" "not_exist" +} + +test_region() +{ + region_dir=$1 + ensure_dir "$region_dir" "exist" + ensure_file "$region_dir/start" "exist" 600 + ensure_file "$region_dir/end" "exist" 600 +} + +test_regions() +{ + regions_dir=$1 + ensure_dir "$regions_dir" "exist" + ensure_file "$regions_dir/nr_regions" "exist" 600 + + ensure_write_succ "$regions_dir/nr_regions" "1" "valid input" + test_region "$regions_dir/0" + + ensure_write_succ "$regions_dir/nr_regions" "2" "valid input" + test_region "$regions_dir/0" + test_region "$regions_dir/1" + + ensure_write_succ "$regions_dir/nr_regions" "0" "valid input" + ensure_dir "$regions_dir/0" "not_exist" + ensure_dir "$regions_dir/1" "not_exist" +} + +test_target() +{ + target_dir=$1 + ensure_dir "$target_dir" "exist" + ensure_file "$target_dir/pid_target" "exist" "600" + test_regions "$target_dir/regions" +} + +test_targets() +{ + targets_dir=$1 + ensure_dir "$targets_dir" "exist" + ensure_file "$targets_dir/nr_targets" "exist" 600 + + ensure_write_succ "$targets_dir/nr_targets" "1" "valid input" + test_target "$targets_dir/0" + + ensure_write_succ "$targets_dir/nr_targets" "2" "valid input" + test_target "$targets_dir/0" + test_target "$targets_dir/1" + + ensure_write_succ "$targets_dir/nr_targets" "0" "valid input" + ensure_dir "$targets_dir/0" "not_exist" + ensure_dir "$targets_dir/1" "not_exist" +} + +test_intervals() +{ + intervals_dir=$1 + ensure_dir "$intervals_dir" "exist" + ensure_file "$intervals_dir/aggr_us" "exist" "600" + ensure_file "$intervals_dir/sample_us" "exist" "600" + ensure_file "$intervals_dir/update_us" "exist" "600" +} + +test_monitoring_attrs() +{ + monitoring_attrs_dir=$1 + ensure_dir "$monitoring_attrs_dir" "exist" + test_intervals "$monitoring_attrs_dir/intervals" + test_range "$monitoring_attrs_dir/nr_regions" +} + +test_context() +{ + context_dir=$1 + ensure_dir "$context_dir" "exist" + ensure_file "$context_dir/operations" "exist" 600 + test_monitoring_attrs "$context_dir/monitoring_attrs" + test_targets "$context_dir/targets" + test_schemes "$context_dir/schemes" +} + +test_contexts() +{ + contexts_dir=$1 + ensure_dir "$contexts_dir" "exist" + ensure_file "$contexts_dir/nr_contexts" "exist" 600 + + ensure_write_succ "$contexts_dir/nr_contexts" "1" "valid input" + test_context "$contexts_dir/0" + + ensure_write_fail "$contexts_dir/nr_contexts" "2" "only 0/1 are supported" + test_context "$contexts_dir/0" + + ensure_write_succ "$contexts_dir/nr_contexts" "0" "valid input" + ensure_dir "$contexts_dir/0" "not_exist" +} + +test_kdamond() +{ + kdamond_dir=$1 + ensure_dir "$kdamond_dir" "exist" + ensure_file "$kdamond_dir/state" "exist" "600" + ensure_file "$kdamond_dir/pid" "exist" 400 + test_contexts "$kdamond_dir/contexts" +} + +test_kdamonds() +{ + kdamonds_dir=$1 + ensure_dir "$kdamonds_dir" "exist" + + ensure_file "$kdamonds_dir/nr_kdamonds" "exist" "600" + + ensure_write_succ "$kdamonds_dir/nr_kdamonds" "1" "valid input" + test_kdamond "$kdamonds_dir/0" + + ensure_write_succ "$kdamonds_dir/nr_kdamonds" "2" "valid input" + test_kdamond "$kdamonds_dir/0" + test_kdamond "$kdamonds_dir/1" + + ensure_write_succ "$kdamonds_dir/nr_kdamonds" "0" "valid input" + ensure_dir "$kdamonds_dir/0" "not_exist" + ensure_dir "$kdamonds_dir/1" "not_exist" +} + +test_damon_sysfs() +{ + damon_sysfs=$1 + if [ ! -d "$damon_sysfs" ] + then + echo "$damon_sysfs not found" + exit $ksft_skip + fi + + test_kdamonds "$damon_sysfs/kdamonds" +} + +check_dependencies() +{ + if [ $EUID -ne 0 ] + then + echo "Run as root" + exit $ksft_skip + fi +} + +check_dependencies +test_damon_sysfs "/sys/kernel/mm/damon/admin"

This commit adds DAMON sysfs interface ABI document under Documentation/ABI/testing.

Signed-off-by: SeongJae Park sj@kernel.org --- .../ABI/testing/sysfs-kernel-mm-damon | 274 ++++++++++++++++++ MAINTAINERS | 1 + 2 files changed, 275 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-kernel-mm-damon

diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-damon b/Documentation/ABI/testing/sysfs-kernel-mm-damon new file mode 100644 index 000000000000..9e282065cbcf --- /dev/null +++ b/Documentation/ABI/testing/sysfs-kernel-mm-damon @@ -0,0 +1,274 @@ +what: /sys/kernel/mm/damon/ +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Interface for Data Access MONitoring (DAMON). Contains files + for controlling DAMON. For more details on DAMON itself, + please refer to Documentation/admin-guide/mm/damon/index.rst. + +What: /sys/kernel/mm/damon/admin/ +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Interface for privileged users of DAMON. Contains files for + controlling DAMON that aimed to be used by privileged users. + +What: /sys/kernel/mm/damon/admin/kdamonds/nr_kdamonds +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing a number 'N' to this file creates the number of + directories for controlling each DAMON worker thread (kdamond) + named '0' to 'N-1' under the kdamonds/ directory. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/state +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing 'on' or 'off' to this file makes the kdamond starts or + stops, respectively. Reading the file returns the keywords + based on the current status. Writing 'update_schemes_stats' to + the file updates contents of schemes stats files of the + kdamond. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/pid +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Reading this file returns the pid of the kdamond if it is + running. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/nr_contexts +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing a number 'N' to this file creates the number of + directories for controlling each DAMON context named '0' to + 'N-1' under the contexts/ directory. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/operations +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing a keyword for a monitoring operations set ('vaddr' for + virtual address spaces monitoring, and 'paddr' for the physical + address space monitoring) to this file makes the context to use + the operations set. Reading the file returns the keyword for + the operations set the context is set to use. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/monitoring_attrs/intervals/sample_us +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing a value to this file sets the sampling interval of the + DAMON context in microseconds as the value. Reading this file + returns the value. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/monitoring_attrs/intervals/aggr_us +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing a value to this file sets the aggregation interval of + the DAMON context in microseconds as the value. Reading this + file returns the value. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/monitoring_attrs/intervals/update_us +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing a value to this file sets the update interval of the + DAMON context in microseconds as the value. Reading this file + returns the value. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/monitoring_attrs/nr_regions/min + +WDate: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing a value to this file sets the minimum number of + monitoring regions of the DAMON context as the value. Reading + this file returns the value. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/monitoring_attrs/nr_regions/max +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing a value to this file sets the maximum number of + monitoring regions of the DAMON context as the value. Reading + this file returns the value. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/targets/nr_targets +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing a number 'N' to this file creates the number of + directories for controlling each DAMON target of the context + named '0' to 'N-1' under the contexts/ directory. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/targets/<T>/pid_target +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the pid of + the target process if the context is for virtual address spaces + monitoring, respectively. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/targets/<T>/regions/nr_regions +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing a number 'N' to this file creates the number of + directories for setting each DAMON target memory region of the + context named '0' to 'N-1' under the regions/ directory. In + case of the virtual address space monitoring, DAMON + automatically sets the target memory region based on the target + processes' mappings. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/targets/<T>/regions/<R>/start +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the start + address of the monitoring region. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/targets/<T>/regions/<R>/end +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the end + address of the monitoring region. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/nr_schemes +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing a number 'N' to this file creates the number of + directories for controlling each DAMON-based operation scheme + of the context named '0' to 'N-1' under the schemes/ directory. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/action +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the action + of the scheme. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/access_pattern/sz/min +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the mimimum + size of the scheme's target regions in bytes. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/access_pattern/sz/max +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the maximum + size of the scheme's target regions in bytes. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/access_pattern/nr_accesses/min +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the manimum + 'nr_accesses' of the scheme's target regions. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/access_pattern/nr_accesses/max +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the maximum + 'nr_accesses' of the scheme's target regions. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/access_pattern/age/min +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the minimum + 'age' of the scheme's target regions. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/access_pattern/age/max +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the maximum + 'age' of the scheme's target regions. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/quotas/ms +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the time + quota of the scheme in milliseconds. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/quotas/bytes +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the size + quota of the scheme in bytes. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/quotas/reset_interval_ms +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the quotas + charge reset interval of the scheme in milliseconds. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/quotas/weights/sz_permil +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the + under-quota limit regions prioritization weight for 'size' in + permil. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/quotas/weights/nr_accesses_permil +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the + under-quota limit regions prioritization weight for + 'nr_accesses' in permil. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/quotas/weights/age_permil +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the + under-quota limit regions prioritization weight for 'age' in + permil. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/watermarks/metric +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the metric + of the watermarks for the scheme. The writable/readable + keywords for this file are 'none' for disabling the watermarks + feature, or 'free_mem_rate' for the system's global free memory + rate in permil. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/watermarks/interval_us +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the metric + check interval of the watermarks for the scheme in + microseconds. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/watermarks/high +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the high + watermark of the scheme in permil. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/watermarks/mid +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the mid + watermark of the scheme in permil. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/watermarks/low +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Writing to and reading from this file sets and gets the low + watermark of the scheme in permil. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/stats/nr_tried +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Reading this file returns the number of regions that the action + of the scheme has tried to be applied. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/stats/sz_tried +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Reading this file returns the total size of regions that the + action of the scheme has tried to be applied in bytes. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/stats/nr_applied +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Reading this file returns the number of regions that the action + of the scheme has successfully applied. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/stats/sz_applied +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Reading this file returns the total size of regions that the + action of the scheme has successfully applied in bytes. + +What: /sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/schemes/<S>/stats/qt_exceeds +Date: Mar 2022 +Contact: SeongJae Park sj@kernel.org +Description: Reading this file returns the number of the exceed events of + the scheme's quotas. diff --git a/MAINTAINERS b/MAINTAINERS index 0153a614bab0..f45c6d381e22 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -5416,6 +5416,7 @@ DATA ACCESS MONITOR M: SeongJae Park sj@kernel.org L: linux-mm@kvack.org S: Maintained +F: Documentation/ABI/testing/sysfs-kernel-mm-damon F: Documentation/admin-guide/mm/damon/ F: Documentation/vm/damon/ F: include/linux/damon.h

On 2/28/22 4:13 PM, SeongJae Park wrote:

This commit makes DAMON sysfs interface supports the physical address space monitoring. Specifically, this commit adds support of the initial monitoring regions set feature by adding 'regions' directory under each target directory and makes context operations file to receive 'paddr' in addition to 'vaddr'.

As a result, the files hierarchy becomes as below:

 /sys/kernel/mm/damon/admin
 │ kdamonds/nr_kdamonds
 │ │ 0/state,pid
 │ │ │ contexts/nr_contexts
 │ │ │ │ 0/operations
 │ │ │ │ │ monitoring_attrs/
 │ │ │ │ │ │ intervals/sample_us,aggr_us,update_us
 │ │ │ │ │ │ nr_regions/min,max
 │ │ │ │ │ targets/nr_targets
 │ │ │ │ │ │ 0/pid_target
 │ │ │ │ │ │ │ regions/nr_regions    <- NEW DIRECTORY
 │ │ │ │ │ │ │ │ 0/start,end
 │ │ │ │ │ │ │ │ ...
 │ │ │ │ │ │ ...
 │ │ │ │ ...
 │ │ ...

Signed-off-by: SeongJae Park sj@kernel.org

mm/damon/sysfs.c | 276 ++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 271 insertions(+), 5 deletions(-)

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index 9221c93db6cc..968a4ba8e81b 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -113,12 +113,220 @@ static struct kobj_type damon_sysfs_ul_range_ktype = { .default_groups = damon_sysfs_ul_range_groups, }; +/*

• • init region directory
• */

+struct damon_sysfs_region {

• struct kobject kobj;
• unsigned long start;
• unsigned long end;

+};

+static struct damon_sysfs_region *damon_sysfs_region_alloc(

• unsigned long start,
  

• unsigned long end)
  

+{

• struct damon_sysfs_region *region = kmalloc(sizeof(*region),

• 	GFP_KERNEL);
  

• if (!region)

• return NULL;
  

• region->kobj = (struct kobject){};
• region->start = start;
• region->end = end;
• return region;

+}

The interface "start" and "end" have the same problems

[root@rt2k03395 0]# echo 100 > start [root@rt2k03395 0]# echo 10 > end [root@rt2k03395 0]# cat end 10 [root@rt2k03395 0]# cat start 100

+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->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->start);
• if (err)

• return -EINVAL;
  

• return 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->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->end);
• if (err)

• return -EINVAL;
  

• return 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(0, 0);
  

• 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 = container_of(kobj,

• 	struct damon_sysfs_regions, kobj);
  

• int nr, err = kstrtoint(buf, 0, &nr);
• if (err)

• return err;
  

• if (nr < 0)

• return -EINVAL;
  

• 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; };

@@ -127,6 +335,29 @@ 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) {

@@ -188,8 +419,10 @@ 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++)

• 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;

@@ -224,6 +457,10 @@ static int damon_sysfs_targets_add_dirs(struct damon_sysfs_targets *targets, if (err) goto out;

• err = damon_sysfs_target_add_dirs(target);
  

• if (err)
  

• 	goto out;
  

• targets_arr[i] = target; targets->nr++; }

@@ -608,9 +845,6 @@ static ssize_t operations_store(struct kobject *kobj, for (id = 0; id < NR_DAMON_OPS; id++) { if (sysfs_streq(buf, damon_sysfs_ops_strs[id])) {

• 	/* Support only vaddr */
  

• 	if (id != DAMON_OPS_VADDR)
  

• 		return -EINVAL;
  context->ops_id = id;
  return count;
  

  }

@@ -855,10 +1089,37 @@ static void damon_sysfs_destroy_targets(struct damon_ctx *ctx) } } +static int damon_sysfs_set_regions(struct damon_target *t,

• struct damon_sysfs_regions *sysfs_regions)
  

+{

• int i;
• for (i = 0; i < sysfs_regions->nr; i++) {

• struct damon_sysfs_region *sys_region =
  

• 	sysfs_regions->regions_arr[i];
  

• struct damon_region *prev, *r;
  

• if (sys_region->start > sys_region->end)
  

• 	return -EINVAL;
  

• r = damon_new_region(sys_region->start, sys_region->end);
  

• if (!r)
  

• 	return -ENOMEM;
  

• damon_add_region(r, t);
  

• if (damon_nr_regions(t) > 1) {
  

• 	prev = damon_prev_region(r);
  

• 	if (prev->ar.end > r->ar.start) {
  

• 		damon_destroy_region(r, t);
  

• 		return -EINVAL;
  

• 	}
  

• }
  

• }
• return 0;

+}

• static int damon_sysfs_set_targets(struct damon_ctx *ctx, struct damon_sysfs_targets *sysfs_targets) {

• int i;

• int i, err;

for (i = 0; i < sysfs_targets->nr; i++) { struct damon_sysfs_target *sys_target = @@ -877,6 +1138,11 @@ static int damon_sysfs_set_targets(struct damon_ctx *ctx, } } damon_add_target(ctx, t);

• err = damon_sysfs_set_regions(t, sys_target->regions);
  

• if (err) {
  

• 	damon_sysfs_destroy_targets(ctx);
  

• 	return err;
  

• }
  

  } return 0; }

On Tue, 1 Mar 2022 00:11:12 +0800 xhao@linux.alibaba.com wrote:

On 2/28/22 4:13 PM, SeongJae Park wrote:

...

This commit makes DAMON sysfs interface supports the physical address space monitoring. Specifically, this commit adds support of the initial monitoring regions set feature by adding 'regions' directory under each target directory and makes context operations file to receive 'paddr' in addition to 'vaddr'.

As a result, the files hierarchy becomes as below:

 /sys/kernel/mm/damon/admin
 │ kdamonds/nr_kdamonds
 │ │ 0/state,pid
 │ │ │ contexts/nr_contexts
 │ │ │ │ 0/operations
 │ │ │ │ │ monitoring_attrs/
 │ │ │ │ │ │ intervals/sample_us,aggr_us,update_us
 │ │ │ │ │ │ nr_regions/min,max
 │ │ │ │ │ targets/nr_targets
 │ │ │ │ │ │ 0/pid_target
 │ │ │ │ │ │ │ regions/nr_regions    <- NEW DIRECTORY
 │ │ │ │ │ │ │ │ 0/start,end
 │ │ │ │ │ │ │ │ ...
 │ │ │ │ │ │ ...
 │ │ │ │ ...
 │ │ ...

Signed-off-by: SeongJae Park sj@kernel.org

mm/damon/sysfs.c | 276 ++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 271 insertions(+), 5 deletions(-)

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index 9221c93db6cc..968a4ba8e81b 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -113,12 +113,220 @@ static struct kobj_type damon_sysfs_ul_range_ktype = { .default_groups = damon_sysfs_ul_range_groups, }; +/*

• • init region directory
• */

+struct damon_sysfs_region {

• struct kobject kobj;
• unsigned long start;
• unsigned long end;

+};

+static struct damon_sysfs_region *damon_sysfs_region_alloc(

• unsigned long start,
  

• unsigned long end)
  

+{

• struct damon_sysfs_region *region = kmalloc(sizeof(*region),

• 	GFP_KERNEL);
  

• if (!region)

• return NULL;
  

• region->kobj = (struct kobject){};
• region->start = start;
• region->end = end;
• return region;

+}

The interface "start" and "end" have the same problems

[root@rt2k03395 0]# echo 100 > start [root@rt2k03395 0]# echo 10 > end [root@rt2k03395 0]# cat end 10 [root@rt2k03395 0]# cat start 100

As mentioned on the above answer[1], this is an intended behavior, so I don't think a fix is needed.

[1] https://lore.kernel.org/linux-mm/20220228162318.4046-1-sj@kernel.org/

Thanks, SJ

[...]

-- Best Regards! Xin Hao