void btrfs_discard_calc_delay(struct btrfs_discard_ctl *discard_ctl)
{
s32 discardable_extents;
+ s64 discardable_bytes;
u32 iops_limit;
unsigned long delay;
unsigned long lower_limit = BTRFS_DISCARD_MIN_DELAY_MSEC;
spin_lock(&discard_ctl->lock);
+ /*
+ * The following is to fix a potential -1 discrepenancy that we're not
+ * sure how to reproduce. But given that this is the only place that
+ * utilizes these numbers and this is only called by from
+ * btrfs_finish_extent_commit() which is synchronized, we can correct
+ * here.
+ */
+ if (discardable_extents < 0)
+ atomic_add(-discardable_extents,
+ &discard_ctl->discardable_extents);
+
+ discardable_bytes = atomic64_read(&discard_ctl->discardable_bytes);
+ if (discardable_bytes < 0)
+ atomic64_add(-discardable_bytes,
+ &discard_ctl->discardable_bytes);
+
+ if (discardable_extents <= 0) {
+ spin_unlock(&discard_ctl->lock);
+ return;
+ }
+
iops_limit = READ_ONCE(discard_ctl->iops_limit);
if (iops_limit)
lower_limit = max_t(unsigned long, lower_limit,