diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index 4455e4bef88db..39b2b8d828190 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -808,22 +808,208 @@ static void damon_sysfs_kdamond_rm_dirs(struct damon_sysfs_kdamond *kdamond) kobject_put(&kdamond->contexts->kobj); } +static bool damon_sysfs_ctx_running(struct damon_ctx *ctx) +{ + bool running; + + mutex_lock(&ctx->kdamond_lock); + running = ctx->kdamond != NULL; + mutex_unlock(&ctx->kdamond_lock); + return running; +} + static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return -EINVAL; + struct damon_sysfs_kdamond *kdamond = container_of(kobj, + struct damon_sysfs_kdamond, kobj); + struct damon_ctx *ctx = kdamond->damon_ctx; + bool running; + + if (!ctx) + running = false; + else + running = damon_sysfs_ctx_running(ctx); + + return sysfs_emit(buf, "%s\n", running ? "on" : "off"); +} + +static int damon_sysfs_set_attrs(struct damon_ctx *ctx, + struct damon_sysfs_attrs *sys_attrs) +{ + struct damon_sysfs_intervals *sys_intervals = sys_attrs->intervals; + struct damon_sysfs_ul_range *sys_nr_regions = + sys_attrs->nr_regions_range; + + return damon_set_attrs(ctx, sys_intervals->sample_us, + sys_intervals->aggr_us, sys_intervals->update_us, + sys_nr_regions->min, sys_nr_regions->max); +} + +static void damon_sysfs_destroy_targets(struct damon_ctx *ctx) +{ + struct damon_target *t, *next; + + damon_for_each_target_safe(t, next, ctx) { + if (ctx->ops.id == DAMON_OPS_VADDR) + put_pid(t->pid); + damon_destroy_target(t); + } +} + +static int damon_sysfs_set_targets(struct damon_ctx *ctx, + struct damon_sysfs_targets *sysfs_targets) +{ + int i; + + for (i = 0; i < sysfs_targets->nr; i++) { + struct damon_sysfs_target *sys_target = + sysfs_targets->targets_arr[i]; + struct damon_target *t = damon_new_target(); + + if (!t) { + damon_sysfs_destroy_targets(ctx); + return -ENOMEM; + } + if (ctx->ops.id == DAMON_OPS_VADDR) { + t->pid = find_get_pid(sys_target->pid); + if (!t->pid) { + damon_sysfs_destroy_targets(ctx); + return -EINVAL; + } + } + damon_add_target(ctx, t); + } + return 0; +} + +static void damon_sysfs_before_terminate(struct damon_ctx *ctx) +{ + struct damon_target *t, *next; + + if (ctx->ops.id != DAMON_OPS_VADDR) + return; + + mutex_lock(&ctx->kdamond_lock); + damon_for_each_target_safe(t, next, ctx) { + put_pid(t->pid); + damon_destroy_target(t); + } + mutex_unlock(&ctx->kdamond_lock); +} + +static struct damon_ctx *damon_sysfs_build_ctx( + struct damon_sysfs_context *sys_ctx) +{ + struct damon_ctx *ctx = damon_new_ctx(); + int err; + + if (!ctx) + return ERR_PTR(-ENOMEM); + + err = damon_select_ops(ctx, sys_ctx->ops_id); + if (err) + goto out; + err = damon_sysfs_set_attrs(ctx, sys_ctx->attrs); + if (err) + goto out; + err = damon_sysfs_set_targets(ctx, sys_ctx->targets); + if (err) + goto out; + + ctx->callback.before_terminate = damon_sysfs_before_terminate; + return ctx; + +out: + damon_destroy_ctx(ctx); + return ERR_PTR(err); +} + +static int damon_sysfs_turn_damon_on(struct damon_sysfs_kdamond *kdamond) +{ + struct damon_ctx *ctx; + int err; + + if (kdamond->damon_ctx && + damon_sysfs_ctx_running(kdamond->damon_ctx)) + return -EBUSY; + /* TODO: support multiple contexts per kdamond */ + if (kdamond->contexts->nr != 1) + return -EINVAL; + + if (kdamond->damon_ctx) + damon_destroy_ctx(kdamond->damon_ctx); + kdamond->damon_ctx = NULL; + + ctx = damon_sysfs_build_ctx(kdamond->contexts->contexts_arr[0]); + if (IS_ERR(ctx)) + return PTR_ERR(ctx); + err = damon_start(&ctx, 1, false); + if (err) { + damon_destroy_ctx(ctx); + return err; + } + kdamond->damon_ctx = ctx; + return err; +} + +static int damon_sysfs_turn_damon_off(struct damon_sysfs_kdamond *kdamond) +{ + if (!kdamond->damon_ctx) + return -EINVAL; + return damon_stop(&kdamond->damon_ctx, 1); + /* + * To allow users show final monitoring results of already turned-off + * DAMON, we free kdamond->damon_ctx in next + * damon_sysfs_turn_damon_on(), or kdamonds_nr_store() + */ } static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { - return -EINVAL; + struct damon_sysfs_kdamond *kdamond = container_of(kobj, + struct damon_sysfs_kdamond, kobj); + ssize_t ret; + + if (!mutex_trylock(&damon_sysfs_lock)) + return -EBUSY; + if (sysfs_streq(buf, "on")) + ret = damon_sysfs_turn_damon_on(kdamond); + else if (sysfs_streq(buf, "off")) + ret = damon_sysfs_turn_damon_off(kdamond); + else + ret = -EINVAL; + mutex_unlock(&damon_sysfs_lock); + if (!ret) + ret = count; + return ret; } static ssize_t pid_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return -EINVAL; + struct damon_sysfs_kdamond *kdamond = container_of(kobj, + struct damon_sysfs_kdamond, kobj); + struct damon_ctx *ctx; + int pid; + + if (!mutex_trylock(&damon_sysfs_lock)) + return -EBUSY; + ctx = kdamond->damon_ctx; + if (!ctx) { + pid = -1; + goto out; + } + mutex_lock(&ctx->kdamond_lock); + if (!ctx->kdamond) + pid = -1; + else + pid = ctx->kdamond->pid; + mutex_unlock(&ctx->kdamond_lock); +out: + mutex_unlock(&damon_sysfs_lock); + return sysfs_emit(buf, "%d\n", pid); } static void damon_sysfs_kdamond_release(struct kobject *kobj)