From: Eli Cohen <e...@mellanox.com>
First the function retrieving the index of the first hi latency class
blue flame register. High latency class bfregs are located right above
medium latency class bfregs.
Fixes: c1be5232d21d ('IB/mlx5: Fix micro UAR allocator')
Signed-off-by: Eli Cohen <e...@mellanox.com>
Reviewed-by: Matan Barak <mat...@mellanox.com>
Signed-off-by: Leon Romanovsky <l...@kernel.org>
Signed-off-by: Saeed Mahameed <sae...@mellanox.com>
---
drivers/infiniband/hw/mlx5/qp.c | 24 ++++++++++++++----------
1 file changed, 14 insertions(+), 10 deletions(-)
diff --git a/drivers/infiniband/hw/mlx5/qp.c b/drivers/infiniband/hw/mlx5/qp.c
index fbea9bd..240fbb0 100644
--- a/drivers/infiniband/hw/mlx5/qp.c
+++ b/drivers/infiniband/hw/mlx5/qp.c
@@ -490,12 +490,21 @@ static int next_bfreg(int n)
return n;
}
+enum {
+ /* this is the first blue flame register in the array of bfregs assigned
+ * to a processes. Since we do not use it for blue flame but rather
+ * regular 64 bit doorbells, we do not need a lock for maintaiing
+ * "odd/even" order
+ */
+ NUM_NON_BLUE_FLAME_BFREGS = 1,
+};
+
static int num_med_bfreg(struct mlx5_bfreg_info *bfregi)
{
int n;
n = bfregi->num_uars * MLX5_NON_FP_BFREGS_PER_UAR -
- bfregi->num_low_latency_bfregs - 1;
+ bfregi->num_low_latency_bfregs - NUM_NON_BLUE_FLAME_BFREGS;
return n >= 0 ? n : 0;
}
@@ -508,17 +517,9 @@ static int max_bfregi(struct mlx5_bfreg_info *bfregi)
static int first_hi_bfreg(struct mlx5_bfreg_info *bfregi)
{
int med;
- int i;
- int t;
med = num_med_bfreg(bfregi);
- for (t = 0, i = first_med_bfreg();; i = next_bfreg(i)) {
- t++;
- if (t == med)
- return next_bfreg(i);
- }
-
- return 0;
+ return next_bfreg(med);
}
static int alloc_high_class_bfreg(struct mlx5_bfreg_info *bfregi)
@@ -544,6 +545,8 @@ static int alloc_med_class_bfreg(struct mlx5_bfreg_info
*bfregi)
for (i = first_med_bfreg(); i < first_hi_bfreg(bfregi); i =
next_bfreg(i)) {
if (bfregi->count[i] < bfregi->count[minidx])
minidx = i;
+ if (!bfregi->count[minidx])
+ break;
}
bfregi->count[minidx]++;
@@ -558,6 +561,7 @@ static int alloc_bfreg(struct mlx5_bfreg_info *bfregi,
mutex_lock(&bfregi->lock);
switch (lat) {
case MLX5_IB_LATENCY_CLASS_LOW:
+ BUILD_BUG_ON(NUM_NON_BLUE_FLAME_BFREGS != 1);
bfregn = 0;
bfregi->count[bfregn]++;
break;
--
2.7.4
