zram: move zram size warning to documentation

Move zram warning about disksize and size of memory correlation to zram
documentation.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit e64cd51d2fa87733176246101df871a8ac5c7c20)
Signed-off-by: Alex Shi <alex.shi@linaro.org>

diff --git a/Documentation/blockdev/zram.txt b/Documentation/blockdev/zram.txt
index 2eccddffa6c8fde5cdd4d5cc49cecab0b82b8206..393541be1ec0ef62fecbc5541de3f6648b71a993 100644 (file)
--- a/Documentation/blockdev/zram.txt
+++ b/Documentation/blockdev/zram.txt
@@ -33,6 +33,11 @@ Following shows a typical sequence of steps for using zram.
             echo 512M > /sys/block/zram0/disksize
             echo 1G > /sys/block/zram0/disksize
 
+Note:
+There is little point creating a zram of greater than twice the size of memory
+since we expect a 2:1 compression ratio. Note that zram uses about 0.1% of the
+size of the disk when not in use so a huge zram is wasteful.
+
 3) Activate:
        mkswap /dev/zram0
        swapon /dev/zram0

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 4043e783e50ac9ccb8e5b96898ed4c3e8b3ed822..a083dffb699ef88a57a13b2c8cdb2c95ec7f539d 100644 (file)
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -534,23 +534,8 @@ static void zram_reset_device(struct zram *zram, bool reset_capacity)
 
 static void zram_init_device(struct zram *zram, struct zram_meta *meta)
 {
-       if (zram->disksize > 2 * (totalram_pages << PAGE_SHIFT)) {
-               pr_info(
-               "There is little point creating a zram of greater than "
-               "twice the size of memory since we expect a 2:1 compression "
-               "ratio. Note that zram uses about 0.1%% of the size of "
-               "the disk when not in use so a huge zram is "
-               "wasteful.\n"
-               "\tMemory Size: %lu kB\n"
-               "\tSize you selected: %llu kB\n"
-               "Continuing anyway ...\n",
-               (totalram_pages << PAGE_SHIFT) >> 10, zram->disksize >> 10
-               );
-       }
-
        /* zram devices sort of resembles non-rotational disks */
        queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue);
-
        zram->meta = meta;
        pr_debug("Initialization done!\n");
 }