zram: export new 'mm_stat' sysfs attrs

Per-device `zram<id>/mm_stat' file provides mm statistics of a particular
zram device in a format similar to block layer statistics.  The file
consists of a single line and represents the following stats (separated by
whitespace):

        orig_data_size
        compr_data_size
        mem_used_total
        mem_limit
        mem_used_max
        zero_pages
        num_migrated

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Sergey Senozhatsky 2015-04-15 16:16:06 -07:00 committed by Linus Torvalds
parent 2f6a3bed73
commit 4f2109f608
3 changed files with 51 additions and 0 deletions

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@ -158,3 +158,11 @@ Description:
statistics not accounted by block layer. For example,
failed_reads, failed_writes, etc. File format is similar to
block layer statistics file format.
What: /sys/block/zram<id>/mm_stat
Date: August 2015
Contact: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Description:
The mm_stat file is read-only and represents device's mm
statistics (orig_data_size, compr_data_size, etc.) in a format
similar to block layer statistics file format.

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@ -144,6 +144,18 @@ whitespace:
invalid_io
notify_free
File /sys/block/zram<id>/mm_stat
The stat file represents device's mm statistics. It consists of a single
line of text and contains the following stats separated by whitespace:
orig_data_size
compr_data_size
mem_used_total
mem_limit
mem_used_max
zero_pages
num_migrated
8) Deactivate:
swapoff /dev/zram0
umount /dev/zram1

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@ -1051,7 +1051,37 @@ static ssize_t io_stat_show(struct device *dev,
return ret;
}
static ssize_t mm_stat_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct zram *zram = dev_to_zram(dev);
u64 orig_size, mem_used = 0;
long max_used;
ssize_t ret;
down_read(&zram->init_lock);
if (init_done(zram))
mem_used = zs_get_total_pages(zram->meta->mem_pool);
orig_size = atomic64_read(&zram->stats.pages_stored);
max_used = atomic_long_read(&zram->stats.max_used_pages);
ret = scnprintf(buf, PAGE_SIZE,
"%8llu %8llu %8llu %8lu %8ld %8llu %8llu\n",
orig_size << PAGE_SHIFT,
(u64)atomic64_read(&zram->stats.compr_data_size),
mem_used << PAGE_SHIFT,
zram->limit_pages << PAGE_SHIFT,
max_used << PAGE_SHIFT,
(u64)atomic64_read(&zram->stats.zero_pages),
(u64)atomic64_read(&zram->stats.num_migrated));
up_read(&zram->init_lock);
return ret;
}
static DEVICE_ATTR_RO(io_stat);
static DEVICE_ATTR_RO(mm_stat);
ZRAM_ATTR_RO(num_reads);
ZRAM_ATTR_RO(num_writes);
ZRAM_ATTR_RO(failed_reads);
@ -1080,6 +1110,7 @@ static struct attribute *zram_disk_attrs[] = {
&dev_attr_max_comp_streams.attr,
&dev_attr_comp_algorithm.attr,
&dev_attr_io_stat.attr,
&dev_attr_mm_stat.attr,
NULL,
};