diff options
| author | Coly Li <colyli@suse.de> | 2018-02-07 11:41:44 -0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2018-02-07 12:50:01 -0700 |
| commit | 7a5e3ecbe5b7b58e9a78a3738b28244982822e1c (patch) | |
| tree | 0376b27b78359dde3640a013a269966c184ee5a6 | |
| parent | 682811b3ce1a5a4e20d700939a9042f01dbc66c4 (diff) | |
bcache: set writeback_rate_update_seconds in range [1, 60] seconds
dc->writeback_rate_update_seconds can be set via sysfs and its value can
be set to [1, ULONG_MAX]. It does not make sense to set such a large
value, 60 seconds is long enough value considering the default 5 seconds
works well for long time.
Because dc->writeback_rate_update is a special delayed work, it re-arms
itself inside the delayed work routine update_writeback_rate(). When
stopping it by cancel_delayed_work_sync(), there should be a timeout to
wait and make sure the re-armed delayed work is stopped too. A small max
value of dc->writeback_rate_update_seconds is also helpful to decide a
reasonable small timeout.
This patch limits sysfs interface to set dc->writeback_rate_update_seconds
in range of [1, 60] seconds, and replaces the hand-coded number by macros.
Changelog:
v2: fix a rebase typo in v4, which is pointed out by Michael Lyle.
v1: initial version.
Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | drivers/md/bcache/sysfs.c | 4 | ||||
| -rw-r--r-- | drivers/md/bcache/writeback.c | 2 | ||||
| -rw-r--r-- | drivers/md/bcache/writeback.h | 3 |
3 files changed, 7 insertions, 2 deletions
diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c index c524305cc9a7..4a6a697e1680 100644 --- a/drivers/md/bcache/sysfs.c +++ b/drivers/md/bcache/sysfs.c @@ -218,7 +218,9 @@ STORE(__cached_dev) sysfs_strtoul_clamp(writeback_rate, dc->writeback_rate.rate, 1, INT_MAX); - d_strtoul_nonzero(writeback_rate_update_seconds); + sysfs_strtoul_clamp(writeback_rate_update_seconds, + dc->writeback_rate_update_seconds, + 1, WRITEBACK_RATE_UPDATE_SECS_MAX); d_strtoul(writeback_rate_i_term_inverse); d_strtoul_nonzero(writeback_rate_p_term_inverse); diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c index 58218f7e77c3..f1d2fc15abcc 100644 --- a/drivers/md/bcache/writeback.c +++ b/drivers/md/bcache/writeback.c @@ -655,7 +655,7 @@ void bch_cached_dev_writeback_init(struct cached_dev *dc) dc->writeback_rate.rate = 1024; dc->writeback_rate_minimum = 8; - dc->writeback_rate_update_seconds = 5; + dc->writeback_rate_update_seconds = WRITEBACK_RATE_UPDATE_SECS_DEFAULT; dc->writeback_rate_p_term_inverse = 40; dc->writeback_rate_i_term_inverse = 10000; diff --git a/drivers/md/bcache/writeback.h b/drivers/md/bcache/writeback.h index 66f1c527fa24..587b25599856 100644 --- a/drivers/md/bcache/writeback.h +++ b/drivers/md/bcache/writeback.h @@ -8,6 +8,9 @@ #define MAX_WRITEBACKS_IN_PASS 5 #define MAX_WRITESIZE_IN_PASS 5000 /* *512b */ +#define WRITEBACK_RATE_UPDATE_SECS_MAX 60 +#define WRITEBACK_RATE_UPDATE_SECS_DEFAULT 5 + /* * 14 (16384ths) is chosen here as something that each backing device * should be a reasonable fraction of the share, and not to blow up |