zram: add stat to gather incompressible pages since zram set up

Currently, zram supports the stat via /sys/block/zram/mm_stat to represent
how many of incompressible pages are stored at the moment but it couldn't
show how many times incompressible pages were wrote down since zram set
up.  It's also good indication to see how zram is effective in the system.

Link: https://lkml.kernel.org/r/20201130201907.1284910-1-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Minchan Kim 2020-12-14 19:14:32 -08:00 committed by Linus Torvalds
parent 0d8359620d
commit 194e28da1a
3 changed files with 6 additions and 2 deletions

View file

@ -266,6 +266,7 @@ line of text and contains the following stats separated by whitespace:
No memory is allocated for such pages.
pages_compacted the number of pages freed during compaction
huge_pages the number of incompressible pages
huge_pages_since the number of incompressible pages since zram set up
================ =============================================================
File /sys/block/zram<id>/bd_stat

View file

@ -1084,7 +1084,7 @@ static ssize_t mm_stat_show(struct device *dev,
max_used = atomic_long_read(&zram->stats.max_used_pages);
ret = scnprintf(buf, PAGE_SIZE,
"%8llu %8llu %8llu %8lu %8ld %8llu %8lu %8llu\n",
"%8llu %8llu %8llu %8lu %8ld %8llu %8lu %8llu %8llu\n",
orig_size << PAGE_SHIFT,
(u64)atomic64_read(&zram->stats.compr_data_size),
mem_used << PAGE_SHIFT,
@ -1092,7 +1092,8 @@ static ssize_t mm_stat_show(struct device *dev,
max_used << PAGE_SHIFT,
(u64)atomic64_read(&zram->stats.same_pages),
pool_stats.pages_compacted,
(u64)atomic64_read(&zram->stats.huge_pages));
(u64)atomic64_read(&zram->stats.huge_pages),
(u64)atomic64_read(&zram->stats.huge_pages_since));
up_read(&zram->init_lock);
return ret;
@ -1424,6 +1425,7 @@ static int __zram_bvec_write(struct zram *zram, struct bio_vec *bvec,
if (comp_len == PAGE_SIZE) {
zram_set_flag(zram, index, ZRAM_HUGE);
atomic64_inc(&zram->stats.huge_pages);
atomic64_inc(&zram->stats.huge_pages_since);
}
if (flags) {

View file

@ -78,6 +78,7 @@ struct zram_stats {
atomic64_t notify_free; /* no. of swap slot free notifications */
atomic64_t same_pages; /* no. of same element filled pages */
atomic64_t huge_pages; /* no. of huge pages */
atomic64_t huge_pages_since; /* no. of huge pages since zram set up */
atomic64_t pages_stored; /* no. of pages currently stored */
atomic_long_t max_used_pages; /* no. of maximum pages stored */
atomic64_t writestall; /* no. of write slow paths */