diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-block-zram | 8 | ||||
| -rw-r--r-- | Documentation/blockdev/zram.txt | 11 | ||||
| -rw-r--r-- | drivers/block/zram/zram_drv.c | 29 | ||||
| -rw-r--r-- | drivers/block/zram/zram_drv.h | 5 |
4 files changed, 53 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-block-zram b/Documentation/ABI/testing/sysfs-block-zram index d1f80b077885..65fc33b2f53b 100644 --- a/Documentation/ABI/testing/sysfs-block-zram +++ b/Documentation/ABI/testing/sysfs-block-zram @@ -113,3 +113,11 @@ Contact: Minchan Kim <minchan@kernel.org> Description: The writeback file is write-only and trigger idle and/or huge page writeback to backing device. + +What: /sys/block/zram<id>/bd_stat +Date: November 2018 +Contact: Minchan Kim <minchan@kernel.org> +Description: + The bd_stat file is read-only and represents backing device's + statistics (bd_count, bd_reads, bd_writes) in a format + similar to block layer statistics file format. diff --git a/Documentation/blockdev/zram.txt b/Documentation/blockdev/zram.txt index 806cdaabac83..906df97527a7 100644 --- a/Documentation/blockdev/zram.txt +++ b/Documentation/blockdev/zram.txt @@ -221,6 +221,17 @@ line of text and contains the following stats separated by whitespace: pages_compacted the number of pages freed during compaction huge_pages the number of incompressible pages +File /sys/block/zram<id>/bd_stat + +The stat file represents device's backing device statistics. It consists of +a single line of text and contains the following stats separated by whitespace: + bd_count size of data written in backing device. + Unit: 4K bytes + bd_reads the number of reads from backing device + Unit: 4K bytes + bd_writes the number of writes to backing device + Unit: 4K bytes + 9) Deactivate: swapoff /dev/zram0 umount /dev/zram1 diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 6b5a886c8f32..f1832fa3ba41 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -502,6 +502,7 @@ retry: if (test_and_set_bit(blk_idx, zram->bitmap)) goto retry; + atomic64_inc(&zram->stats.bd_count); return blk_idx; } @@ -511,6 +512,7 @@ static void free_block_bdev(struct zram *zram, unsigned long blk_idx) was_set = test_and_clear_bit(blk_idx, zram->bitmap); WARN_ON_ONCE(!was_set); + atomic64_dec(&zram->stats.bd_count); } static void zram_page_end_io(struct bio *bio) @@ -668,6 +670,7 @@ static ssize_t writeback_store(struct device *dev, continue; } + atomic64_inc(&zram->stats.bd_writes); /* * We released zram_slot_lock so need to check if the slot was * changed. If there is freeing for the slot, we can catch it @@ -757,6 +760,7 @@ static int read_from_bdev_sync(struct zram *zram, struct bio_vec *bvec, static int read_from_bdev(struct zram *zram, struct bio_vec *bvec, unsigned long entry, struct bio *parent, bool sync) { + atomic64_inc(&zram->stats.bd_reads); if (sync) return read_from_bdev_sync(zram, bvec, entry, parent); else @@ -1013,6 +1017,25 @@ static ssize_t mm_stat_show(struct device *dev, return ret; } +#ifdef CONFIG_ZRAM_WRITEBACK +static ssize_t bd_stat_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct zram *zram = dev_to_zram(dev); + ssize_t ret; + + down_read(&zram->init_lock); + ret = scnprintf(buf, PAGE_SIZE, + "%8llu %8llu %8llu\n", + (u64)atomic64_read(&zram->stats.bd_count) * (PAGE_SHIFT - 12), + (u64)atomic64_read(&zram->stats.bd_reads) * (PAGE_SHIFT - 12), + (u64)atomic64_read(&zram->stats.bd_writes) * (PAGE_SHIFT - 12)); + up_read(&zram->init_lock); + + return ret; +} +#endif + static ssize_t debug_stat_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -1033,6 +1056,9 @@ static ssize_t debug_stat_show(struct device *dev, static DEVICE_ATTR_RO(io_stat); static DEVICE_ATTR_RO(mm_stat); +#ifdef CONFIG_ZRAM_WRITEBACK +static DEVICE_ATTR_RO(bd_stat); +#endif static DEVICE_ATTR_RO(debug_stat); static void zram_meta_free(struct zram *zram, u64 disksize) @@ -1759,6 +1785,9 @@ static struct attribute *zram_disk_attrs[] = { #endif &dev_attr_io_stat.attr, &dev_attr_mm_stat.attr, +#ifdef CONFIG_ZRAM_WRITEBACK + &dev_attr_bd_stat.attr, +#endif &dev_attr_debug_stat.attr, NULL, }; diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h index 1ad74f030b6d..bc477803530d 100644 --- a/drivers/block/zram/zram_drv.h +++ b/drivers/block/zram/zram_drv.h @@ -82,6 +82,11 @@ struct zram_stats { atomic_long_t max_used_pages; /* no. of maximum pages stored */ atomic64_t writestall; /* no. of write slow paths */ atomic64_t miss_free; /* no. of missed free */ +#ifdef CONFIG_ZRAM_WRITEBACK + atomic64_t bd_count; /* no. of pages in backing device */ + atomic64_t bd_reads; /* no. of reads from backing device */ + atomic64_t bd_writes; /* no. of writes from backing device */ +#endif }; struct zram { |