The blocks_left calculation does not account for free blocks
between 0 and thresh, so we could be queueing/waiting when
there are enough blocks free.
This has us add in the blocks between 0 and thresh as well as
at the end from thresh to DATA_BLOCK_BITS.
Signed-off-by: Mike Christie <mchristi@xxxxxxxxxx>
---
drivers/target/target_core_user.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c
index 76f0e5a..b7eeb25 100644
--- a/drivers/target/target_core_user.c
+++ b/drivers/target/target_core_user.c
@@ -636,7 +636,7 @@ static void gather_data_area(struct tcmu_dev *udev, struct tcmu_cmd *cmd,
static inline size_t spc_bitmap_free(unsigned long *bitmap, uint32_t thresh)
{
- return DATA_BLOCK_SIZE * (thresh - bitmap_weight(bitmap, thresh));
+ return thresh - bitmap_weight(bitmap, thresh);
}
/*
@@ -676,8 +676,9 @@ static bool is_ring_space_avail(struct tcmu_dev *udev, struct tcmu_cmd *cmd,
/* try to check and get the data blocks as needed */
space = spc_bitmap_free(udev->data_bitmap, udev->dbi_thresh);
- if (space < data_needed) {
- unsigned long blocks_left = DATA_BLOCK_BITS - udev->dbi_thresh;
+ if ((space * DATA_BLOCK_SIZE) < data_needed) {
+ unsigned long blocks_left = DATA_BLOCK_BITS - udev->dbi_thresh +
+ space;
unsigned long grow;
if (blocks_left < blocks_needed) {
--
1.8.3.1
