On Thu, Oct 10, 2019 at 11:41:33AM -0400, Josef Bacik wrote: > On Mon, Oct 07, 2019 at 04:17:41PM -0400, Dennis Zhou wrote: > > Use the number of discardable extents to help guide our discard delay > > interval. This value is reevaluated every transaction commit. > > > > Signed-off-by: Dennis Zhou <[email protected]> > > --- > > fs/btrfs/ctree.h | 2 ++ > > fs/btrfs/discard.c | 31 +++++++++++++++++++++++++++++-- > > fs/btrfs/discard.h | 3 +++ > > fs/btrfs/extent-tree.c | 4 +++- > > fs/btrfs/sysfs.c | 30 ++++++++++++++++++++++++++++++ > > 5 files changed, 67 insertions(+), 3 deletions(-) > > > > diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h > > index 8479ab037812..b0823961d049 100644 > > --- a/fs/btrfs/ctree.h > > +++ b/fs/btrfs/ctree.h > > @@ -449,6 +449,8 @@ struct btrfs_discard_ctl { > > struct list_head discard_list[BTRFS_NR_DISCARD_LISTS]; > > atomic_t discard_extents; > > atomic64_t discardable_bytes; > > + atomic_t delay; > > + atomic_t iops_limit; > > }; > > > > /* delayed seq elem */ > > diff --git a/fs/btrfs/discard.c b/fs/btrfs/discard.c > > index 75a2ff14b3c0..c7afb5f8240d 100644 > > --- a/fs/btrfs/discard.c > > +++ b/fs/btrfs/discard.c > > @@ -15,6 +15,11 @@ > > > > #define BTRFS_DISCARD_DELAY (300ULL * NSEC_PER_SEC) > > > > +/* target discard delay in milliseconds */ > > +#define BTRFS_DISCARD_TARGET_MSEC (6 * 60 * 60ULL * MSEC_PER_SEC) > > +#define BTRFS_DISCARD_MAX_DELAY (10000UL) > > +#define BTRFS_DISCARD_MAX_IOPS (10UL) > > + > > static struct list_head * > > btrfs_get_discard_list(struct btrfs_discard_ctl *discard_ctl, > > struct btrfs_block_group_cache *cache) > > @@ -170,10 +175,12 @@ void btrfs_discard_schedule_work(struct > > btrfs_discard_ctl *discard_ctl, > > > > cache = find_next_cache(discard_ctl, now); > > if (cache) { > > - u64 delay = 0; > > + u64 delay = atomic_read(&discard_ctl->delay); > > > > if (now < cache->discard_delay) > > - delay = nsecs_to_jiffies(cache->discard_delay - now); > > + delay = max_t(u64, delay, > > + nsecs_to_jiffies(cache->discard_delay - > > + now)); > > Small nit, instead > > delay = nsecs_to_jiffies(cache->discard_delay - now); > delay = max_t(u64, delay, > atomic_read(&discard_ctl->delay); > > Looks a little cleaner. Otherwise
Hmmm. Does that work if now > cache->discard_delay? I'm just worried about the max_t with type u64. > > Reviewed-by: Josef Bacik <[email protected]> > > Thanks, > > Josef Thanks, Dennis
