Hi , > -----Original Message----- > From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Juhamatti Kuusisaari > Sent: Monday, July 11, 2016 11:21 AM > To: dev at dpdk.org > Subject: [dpdk-dev] [PATCH] lib: move rte_ring read barrier to correct > location > > Fix the location of the rte_ring data dependency read barrier. > It needs to be called before accessing indexed data to ensure > that the data itself is guaranteed to be correctly updated. > > See more details at kernel/Documentation/memory-barriers.txt > section 'Data dependency barriers'.
Any explanation why? >From my point smp_rmb()s are on the proper places here :) Konstantin > > Signed-off-by: Juhamatti Kuusisaari <juhamatti.kuusisaari at coriant.com> > --- > lib/librte_ring/rte_ring.h | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/lib/librte_ring/rte_ring.h b/lib/librte_ring/rte_ring.h > index eb45e41..a923e49 100644 > --- a/lib/librte_ring/rte_ring.h > +++ b/lib/librte_ring/rte_ring.h > @@ -662,9 +662,10 @@ __rte_ring_mc_do_dequeue(struct rte_ring *r, void > **obj_table, > cons_next); > } while (unlikely(success == 0)); > > + rte_smp_rmb(); > + > /* copy in table */ > DEQUEUE_PTRS(); > - rte_smp_rmb(); > > /* > * If there are other dequeues in progress that preceded us, > @@ -746,9 +747,10 @@ __rte_ring_sc_do_dequeue(struct rte_ring *r, void > **obj_table, > cons_next = cons_head + n; > r->cons.head = cons_next; > > + rte_smp_rmb(); > + > /* copy in table */ > DEQUEUE_PTRS(); > - rte_smp_rmb(); > > __RING_STAT_ADD(r, deq_success, n); > r->cons.tail = cons_next; > -- > 2.9.0 > > > ============================================================ > The information contained in this message may be privileged > and confidential and protected from disclosure. If the reader > of this message is not the intended recipient, or an employee > or agent responsible for delivering this message to the > intended recipient, you are hereby notified that any reproduction, > dissemination or distribution of this communication is strictly > prohibited. If you have received this communication in error, > please notify us immediately by replying to the message and > deleting it from your computer. Thank you. Coriant-Tellabs > ============================================================
