When calculating the maximun I/O size allowed into the buffer, consider
the write size (ws_opt) used by the write thread in order to cover the
case in which, due to flushes, the mem and subm pointers are disaligned
by (ws_opt - 1). This case currently translates into a stall when
an I/O of the largest possible size is submitted.
Fixes: f9f9d1ae2c66 ("lightnvm: pblk: prevent stall due to wb threshold")
Signed-off-by: Javier González <javier@xxxxxxxxxxx>
---
Matias: Can you apply this as a fix to 5.1. This is a case I missed when fixing
the wb threshold, which is also scheduled for 5.1
Thanks,
Javier
drivers/lightnvm/pblk-rl.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/lightnvm/pblk-rl.c b/drivers/lightnvm/pblk-rl.c
index b014957dde0b..a5f8bc2defbc 100644
--- a/drivers/lightnvm/pblk-rl.c
+++ b/drivers/lightnvm/pblk-rl.c
@@ -233,10 +233,15 @@ void pblk_rl_init(struct pblk_rl *rl, int budget, int threshold)
/* To start with, all buffer is available to user I/O writers */
rl->rb_budget = budget;
rl->rb_user_max = budget;
- rl->rb_max_io = threshold ? (budget - threshold) : (budget - 1);
rl->rb_gc_max = 0;
rl->rb_state = PBLK_RL_HIGH;
+ /* Maximize I/O size and ansure that back threshold is respected */
+ if (threshold)
+ rl->rb_max_io = budget - pblk->min_write_pgs_data - threshold;
+ else
+ rl->rb_max_io = budget - pblk->min_write_pgs_data - 1;
+
atomic_set(&rl->rb_user_cnt, 0);
atomic_set(&rl->rb_gc_cnt, 0);
atomic_set(&rl->rb_space, -1);
--
2.17.1
