diff options
| author |   Mike Marciniszyn <mike.marciniszyn@intel.com> | 2019-06-13 08:30:52 -0400 |
|---|---|---|
| committer |   Doug Ledford <dledford@redhat.com> | 2019-06-20 22:35:09 -0400 |
| commit | 4a9ceb7dbadf9e1435644b1f49720ee87431ce26 (patch) | |
| tree | 8a77c25eb30c30d7c27d6781cd3584c35ea1b3a8 /drivers/infiniband/sw/rdmavt/qp.c | |
| parent | IB/rdmavt: Add new completion inline (diff) | |
| download | linux-dev-4a9ceb7dbadf9e1435644b1f49720ee87431ce26.tar.xz linux-dev-4a9ceb7dbadf9e1435644b1f49720ee87431ce26.zip | |
IB/{rdmavt, qib, hfi1}: Convert to new completion API
Convert all completions to use the new completion routine that
fixes a race between post send and completion where fields from
a SWQE can be read after SWQE has been freed.
This patch also addresses issues reported in
https://marc.info/?l=linux-kernel&m=155656897409107&w=2.
The reserved operation path has no need for any barrier.
The barrier for the other path is addressed by the
smp_load_acquire() barrier.
Cc: Andrea Parri <andrea.parri@amarulasolutions.com>
Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Diffstat (limited to 'drivers/infiniband/sw/rdmavt/qp.c')
| -rw-r--r-- | drivers/infiniband/sw/rdmavt/qp.c | 31 |
1 files changed, 9 insertions, 22 deletions
diff --git a/drivers/infiniband/sw/rdmavt/qp.c b/drivers/infiniband/sw/rdmavt/qp.c index a60f5faea198..dfbc7d8640fb 100644 --- a/drivers/infiniband/sw/rdmavt/qp.c +++ b/drivers/infiniband/sw/rdmavt/qp.c @@ -1853,10 +1853,9 @@ static inline int rvt_qp_is_avail( /* see rvt_qp_wqe_unreserve() */ smp_mb__before_atomic(); - reserved_used = atomic_read(&qp->s_reserved_used); if (unlikely(reserved_op)) { /* see rvt_qp_wqe_unreserve() */ - smp_mb__before_atomic(); + reserved_used = atomic_read(&qp->s_reserved_used); if (reserved_used >= rdi->dparms.reserved_operations) return -ENOMEM; return 0; @@ -1864,14 +1863,13 @@ static inline int rvt_qp_is_avail( /* non-reserved operations */ if (likely(qp->s_avail)) return 0; - slast = READ_ONCE(qp->s_last); + /* See rvt_qp_complete_swqe() */ + slast = smp_load_acquire(&qp->s_last); if (qp->s_head >= slast) avail = qp->s_size - (qp->s_head - slast); else avail = slast - qp->s_head; - /* see rvt_qp_wqe_unreserve() */ - smp_mb__before_atomic(); reserved_used = atomic_read(&qp->s_reserved_used); avail = avail - 1 - (rdi->dparms.reserved_operations - reserved_used); @@ -2664,27 +2662,16 @@ void rvt_send_complete(struct rvt_qp *qp, struct rvt_swqe *wqe, enum ib_wc_status status) { u32 old_last, last; - struct rvt_dev_info *rdi = ib_to_rvt(qp->ibqp.device); + struct rvt_dev_info *rdi; if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_OR_FLUSH_SEND)) return; + rdi = ib_to_rvt(qp->ibqp.device); - last = qp->s_last; - old_last = last; - trace_rvt_qp_send_completion(qp, wqe, last); - if (++last >= qp->s_size) - last = 0; - trace_rvt_qp_send_completion(qp, wqe, last); - qp->s_last = last; - /* See post_send() */ - barrier(); - rvt_put_qp_swqe(qp, wqe); - - rvt_qp_swqe_complete(qp, - wqe, - rdi->wc_opcode[wqe->wr.opcode], - status); - + old_last = qp->s_last; + trace_rvt_qp_send_completion(qp, wqe, old_last); + last = rvt_qp_complete_swqe(qp, wqe, rdi->wc_opcode[wqe->wr.opcode], + status); if (qp->s_acked == old_last) qp->s_acked = last; if (qp->s_cur == old_last) |