diff options
| -rw-r--r-- | mm/damon/dbgfs.c | 165 |
1 files changed, 162 insertions, 3 deletions
diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c index faee070977d8..78b7a04490c5 100644 --- a/mm/damon/dbgfs.c +++ b/mm/damon/dbgfs.c @@ -98,6 +98,159 @@ out: return ret; } +static ssize_t sprint_schemes(struct damon_ctx *c, char *buf, ssize_t len) +{ + struct damos *s; + int written = 0; + int rc; + + damon_for_each_scheme(s, c) { + rc = scnprintf(&buf[written], len - written, + "%lu %lu %u %u %u %u %d\n", + s->min_sz_region, s->max_sz_region, + s->min_nr_accesses, s->max_nr_accesses, + s->min_age_region, s->max_age_region, + s->action); + if (!rc) + return -ENOMEM; + + written += rc; + } + return written; +} + +static ssize_t dbgfs_schemes_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + struct damon_ctx *ctx = file->private_data; + char *kbuf; + ssize_t len; + + kbuf = kmalloc(count, GFP_KERNEL); + if (!kbuf) + return -ENOMEM; + + mutex_lock(&ctx->kdamond_lock); + len = sprint_schemes(ctx, kbuf, count); + mutex_unlock(&ctx->kdamond_lock); + if (len < 0) + goto out; + len = simple_read_from_buffer(buf, count, ppos, kbuf, len); + +out: + kfree(kbuf); + return len; +} + +static void free_schemes_arr(struct damos **schemes, ssize_t nr_schemes) +{ + ssize_t i; + + for (i = 0; i < nr_schemes; i++) + kfree(schemes[i]); + kfree(schemes); +} + +static bool damos_action_valid(int action) +{ + switch (action) { + case DAMOS_WILLNEED: + case DAMOS_COLD: + case DAMOS_PAGEOUT: + case DAMOS_HUGEPAGE: + case DAMOS_NOHUGEPAGE: + return true; + default: + return false; + } +} + +/* + * Converts a string into an array of struct damos pointers + * + * Returns an array of struct damos pointers that converted if the conversion + * success, or NULL otherwise. + */ +static struct damos **str_to_schemes(const char *str, ssize_t len, + ssize_t *nr_schemes) +{ + struct damos *scheme, **schemes; + const int max_nr_schemes = 256; + int pos = 0, parsed, ret; + unsigned long min_sz, max_sz; + unsigned int min_nr_a, max_nr_a, min_age, max_age; + unsigned int action; + + schemes = kmalloc_array(max_nr_schemes, sizeof(scheme), + GFP_KERNEL); + if (!schemes) + return NULL; + + *nr_schemes = 0; + while (pos < len && *nr_schemes < max_nr_schemes) { + ret = sscanf(&str[pos], "%lu %lu %u %u %u %u %u%n", + &min_sz, &max_sz, &min_nr_a, &max_nr_a, + &min_age, &max_age, &action, &parsed); + if (ret != 7) + break; + if (!damos_action_valid(action)) { + pr_err("wrong action %d\n", action); + goto fail; + } + + pos += parsed; + scheme = damon_new_scheme(min_sz, max_sz, min_nr_a, max_nr_a, + min_age, max_age, action); + if (!scheme) + goto fail; + + schemes[*nr_schemes] = scheme; + *nr_schemes += 1; + } + return schemes; +fail: + free_schemes_arr(schemes, *nr_schemes); + return NULL; +} + +static ssize_t dbgfs_schemes_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct damon_ctx *ctx = file->private_data; + char *kbuf; + struct damos **schemes; + ssize_t nr_schemes = 0, ret = count; + int err; + + kbuf = user_input_str(buf, count, ppos); + if (IS_ERR(kbuf)) + return PTR_ERR(kbuf); + + schemes = str_to_schemes(kbuf, ret, &nr_schemes); + if (!schemes) { + ret = -EINVAL; + goto out; + } + + mutex_lock(&ctx->kdamond_lock); + if (ctx->kdamond) { + ret = -EBUSY; + goto unlock_out; + } + + err = damon_set_schemes(ctx, schemes, nr_schemes); + if (err) + ret = err; + else + nr_schemes = 0; +unlock_out: + mutex_unlock(&ctx->kdamond_lock); + free_schemes_arr(schemes, nr_schemes); +out: + kfree(kbuf); + return ret; +} + static inline bool targetid_is_pid(const struct damon_ctx *ctx) { return ctx->primitive.target_valid == damon_va_target_valid; @@ -279,6 +432,12 @@ static const struct file_operations attrs_fops = { .write = dbgfs_attrs_write, }; +static const struct file_operations schemes_fops = { + .open = damon_dbgfs_open, + .read = dbgfs_schemes_read, + .write = dbgfs_schemes_write, +}; + static const struct file_operations target_ids_fops = { .open = damon_dbgfs_open, .read = dbgfs_target_ids_read, @@ -292,10 +451,10 @@ static const struct file_operations kdamond_pid_fops = { static void dbgfs_fill_ctx_dir(struct dentry *dir, struct damon_ctx *ctx) { - const char * const file_names[] = {"attrs", "target_ids", + const char * const file_names[] = {"attrs", "schemes", "target_ids", "kdamond_pid"}; - const struct file_operations *fops[] = {&attrs_fops, &target_ids_fops, - &kdamond_pid_fops}; + const struct file_operations *fops[] = {&attrs_fops, &schemes_fops, + &target_ids_fops, &kdamond_pid_fops}; int i; for (i = 0; i < ARRAY_SIZE(file_names); i++) |