From: Sergey Senozhatsky <senozhatsky@chromium.org>
Date: Wed, 9 Nov 2022 11:50:47 +0000 (+0900)
Subject: zram: add incompressible flag to read_block_state()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=77db7bb56bd711586243924a5582727f7a93fb7f;p=linux.git
zram: add incompressible flag to read_block_state()
Add a new flag to zram block state that shows if the page is
incompressible: that none of the algorithm (including secondary ones)
could compress it.
Link: https://lkml.kernel.org/r/20221109115047.2921851-14-senozhatsky@chromium.org
Suggested-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Alexey Romanov <avromanov@sberdevices.ru>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Suleiman Souhlal <suleiman@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
diff --git a/Documentation/admin-guide/blockdev/zram.rst b/Documentation/admin-guide/blockdev/zram.rst
index f14c8c2e42f3e..e4551579cb128 100644
--- a/Documentation/admin-guide/blockdev/zram.rst
+++ b/Documentation/admin-guide/blockdev/zram.rst
@@ -497,10 +497,11 @@ pages of the process with*pagemap.
If you enable the feature, you could see block state via
/sys/kernel/debug/zram/zram0/block_state". The output is as follows::
- 300 75.033841 .wh..
- 301 63.806904 s....
- 302 63.806919 ..hi.
- 303 62.801919 ....r
+ 300 75.033841 .wh...
+ 301 63.806904 s.....
+ 302 63.806919 ..hi..
+ 303 62.801919 ....r.
+ 304 146.781902 ..hi.n
First column
zram's block index.
@@ -519,6 +520,8 @@ Third column
idle page
r:
recompressed page (secondary compression algorithm)
+ n:
+ none (including secondary) of algorithms could compress it
First line of above example says 300th block is accessed at 75.033841sec
and the block's state is huge so it is written back to the backing
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 25b7ff2b56bf3..9d33801e8ba87 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -946,14 +946,16 @@ static ssize_t read_block_state(struct file *file, char __user *buf,
ts = ktime_to_timespec64(zram->table[index].ac_time);
copied = snprintf(kbuf + written, count,
- "%12zd %12lld.%06lu %c%c%c%c%c\n",
+ "%12zd %12lld.%06lu %c%c%c%c%c%c\n",
index, (s64)ts.tv_sec,
ts.tv_nsec / NSEC_PER_USEC,
zram_test_flag(zram, index, ZRAM_SAME) ? 's' : '.',
zram_test_flag(zram, index, ZRAM_WB) ? 'w' : '.',
zram_test_flag(zram, index, ZRAM_HUGE) ? 'h' : '.',
zram_test_flag(zram, index, ZRAM_IDLE) ? 'i' : '.',
- zram_get_priority(zram, index) ? 'r' : '.');
+ zram_get_priority(zram, index) ? 'r' : '.',
+ zram_test_flag(zram, index,
+ ZRAM_INCOMPRESSIBLE) ? 'n' : '.');
if (count <= copied) {
zram_slot_unlock(zram, index);