From b67d1ec189ffb92cdad9b2bd29475fb1e0166983 Mon Sep 17 00:00:00 2001 From: Sergey Senozhatsky Date: Mon, 7 Apr 2014 15:38:09 -0700 Subject: [PATCH] zram: delete zram_init_device() allocate new `zram_meta' in disksize_store() only for uninitialised zram device, saving a number of allocations and deallocations in case if disksize_store() was called on currently used device. at the same time zram_meta stack variable is not necessary, because we can set ->meta directly. there is also no need in setting QUEUE_FLAG_NONROT queue on every disksize_store(), set it once during device creation. [minchan@kernel.org: handle zram->meta alloc fail case] [minchan@kernel.org: prevent lockdep spew of init_lock] Signed-off-by: Sergey Senozhatsky Signed-off-by: Minchan Kim Acked-by: Jerome Marchand Cc: Sasha Levin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/block/zram/zram_drv.c | 16 +++++----------- 1 file changed, 5 insertions(+), 11 deletions(-) diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 21aee3edcb25..76ba67673a90 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -533,14 +533,6 @@ static void zram_reset_device(struct zram *zram, bool reset_capacity) up_write(&zram->init_lock); } -static void zram_init_device(struct zram *zram, struct zram_meta *meta) -{ - /* 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"); -} - static ssize_t disksize_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { @@ -556,17 +548,18 @@ static ssize_t disksize_store(struct device *dev, meta = zram_meta_alloc(disksize); if (!meta) return -ENOMEM; + down_write(&zram->init_lock); if (init_done(zram)) { - up_write(&zram->init_lock); zram_meta_free(meta); + up_write(&zram->init_lock); pr_info("Cannot change disksize for initialized device\n"); return -EBUSY; } + zram->meta = meta; zram->disksize = disksize; set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT); - zram_init_device(zram, meta); up_write(&zram->init_lock); return len; @@ -776,7 +769,8 @@ static int create_device(struct zram *zram, int device_id) /* Actual capacity set using syfs (/sys/block/zram/disksize */ set_capacity(zram->disk, 0); - + /* zram devices sort of resembles non-rotational disks */ + queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue); /* * To ensure that we always get PAGE_SIZE aligned * and n*PAGE_SIZED sized I/O requests. -- 2.39.2