On 2018/4/12 3:21 PM, tang.junhui@xxxxxxxxxx wrote:
> From: Tang Junhui <tang.junhui@xxxxxxxxxx>
>
> Currently we calculate the total amount of flash only devices dirty data
> by adding the dirty data of each flash only device under registering
> locker. It is very inefficient.
>
> In this patch, we add a member flash_dev_dirty_sectors in struct cache_set
> to record the total amount of flash only devices dirty data in real time,
> so we didn't need to calculate the total amount of dirty data any more.
>
> Signed-off-by: Tang Junhui <tang.junhui@xxxxxxxxxx>
Hi Junhui,
The patch looks good to me, you have my
Reviewed-by: Coly Li <colyli@xxxxxxx>
Thanks.
Coly Li
> ---
> drivers/md/bcache/bcache.h | 1 +
> drivers/md/bcache/super.c | 2 ++
> drivers/md/bcache/writeback.c | 5 ++++-
> drivers/md/bcache/writeback.h | 19 -------------------
> 4 files changed, 7 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
> index 843877e..cdbd596 100644
> --- a/drivers/md/bcache/bcache.h
> +++ b/drivers/md/bcache/bcache.h
> @@ -490,6 +490,7 @@ struct cache_set {
> struct bcache_device **devices;
> struct list_head cached_devs;
> uint64_t cached_dev_sectors;
> + atomic_long_t flash_dev_dirty_sectors;
> struct closure caching;
>
> struct closure sb_write;
> diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
> index b4d2892..772520e 100644
> --- a/drivers/md/bcache/super.c
> +++ b/drivers/md/bcache/super.c
> @@ -1208,6 +1208,8 @@ static void flash_dev_free(struct closure *cl)
> {
> struct bcache_device *d = container_of(cl, struct bcache_device, cl);
> mutex_lock(&bch_register_lock);
> + atomic_long_sub(bcache_dev_sectors_dirty(d),
> + &d->c->flash_dev_dirty_sectors);
> bcache_device_free(d);
> mutex_unlock(&bch_register_lock);
> kobject_put(&d->kobj);
> diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c
> index 56a3788..ec50d76 100644
> --- a/drivers/md/bcache/writeback.c
> +++ b/drivers/md/bcache/writeback.c
> @@ -23,7 +23,7 @@ static void __update_writeback_rate(struct cached_dev *dc)
> {
> struct cache_set *c = dc->disk.c;
> uint64_t cache_sectors = c->nbuckets * c->sb.bucket_size -
> - bcache_flash_devs_sectors_dirty(c);
> + atomic_long_read(&c->flash_dev_dirty_sectors);
> uint64_t cache_dirty_target =
> div_u64(cache_sectors * dc->writeback_percent, 100);
> int64_t target = div64_u64(cache_dirty_target * bdev_sectors(dc->bdev),
> @@ -314,6 +314,9 @@ void bcache_dev_sectors_dirty_add(struct cache_set *c, unsigned inode,
> if (!d)
> return;
>
> + if (UUID_FLASH_ONLY(&c->uuids[inode]))
> + atomic_long_add(nr_sectors, &c->flash_dev_dirty_sectors);
> +
> stripe = offset_to_stripe(d, offset);
> stripe_offset = offset & (d->stripe_size - 1);
>
> diff --git a/drivers/md/bcache/writeback.h b/drivers/md/bcache/writeback.h
> index a9e3ffb..1a7eacf 100644
> --- a/drivers/md/bcache/writeback.h
> +++ b/drivers/md/bcache/writeback.h
> @@ -15,25 +15,6 @@ static inline uint64_t bcache_dev_sectors_dirty(struct bcache_device *d)
> return ret;
> }
>
> -static inline uint64_t bcache_flash_devs_sectors_dirty(struct cache_set *c)
> -{
> - uint64_t i, ret = 0;
> -
> - mutex_lock(&bch_register_lock);
> -
> - for (i = 0; i < c->nr_uuids; i++) {
> - struct bcache_device *d = c->devices[i];
> -
> - if (!d || !UUID_FLASH_ONLY(&c->uuids[i]))
> - continue;
> - ret += bcache_dev_sectors_dirty(d);
> - }
> -
> - mutex_unlock(&bch_register_lock);
> -
> - return ret;
> -}
> -
> static inline unsigned offset_to_stripe(struct bcache_device *d,
> uint64_t offset)
> {
>
