diff options
| -rw-r--r-- | drivers/staging/rdma/hfi1/pio.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/drivers/staging/rdma/hfi1/pio.c b/drivers/staging/rdma/hfi1/pio.c index eab58c12d915..8e10857d5b7d 100644 --- a/drivers/staging/rdma/hfi1/pio.c +++ b/drivers/staging/rdma/hfi1/pio.c @@ -1565,6 +1565,7 @@ void sc_release_update(struct send_context *sc) u64 hw_free; u32 head, tail; unsigned long old_free; + unsigned long free; unsigned long extra; unsigned long flags; int code; @@ -1579,7 +1580,7 @@ void sc_release_update(struct send_context *sc) extra = (((hw_free & CR_COUNTER_SMASK) >> CR_COUNTER_SHIFT) - (old_free & CR_COUNTER_MASK)) & CR_COUNTER_MASK; - sc->free = old_free + extra; + free = old_free + extra; trace_hfi1_piofree(sc, extra); /* call sent buffer callbacks */ @@ -1589,7 +1590,7 @@ void sc_release_update(struct send_context *sc) while (head != tail) { pbuf = &sc->sr[tail].pbuf; - if (sent_before(sc->free, pbuf->sent_at)) { + if (sent_before(free, pbuf->sent_at)) { /* not sent yet */ break; } @@ -1603,8 +1604,10 @@ void sc_release_update(struct send_context *sc) if (tail >= sc->sr_size) tail = 0; } - /* update tail, in case we moved it */ sc->sr_tail = tail; + /* make sure tail is updated before free */ + smp_wmb(); + sc->free = free; spin_unlock_irqrestore(&sc->release_lock, flags); sc_piobufavail(sc); } |