I do not see the documentation regarding this in programmer's guide. -----Original Message----- From: Burakov, Anatoly <anatoly.bura...@intel.com> Sent: Tuesday, May 29, 2018 4:10 AM To: Honnappa Nagarahalli <honnappa.nagaraha...@arm.com>; olivier.m...@6wind.com Cc: dev@dpdk.org Subject: Re: [dpdk-dev] [PATCH v2] rte_ring: clarify preemptible nature of ring algorithm
On 29-May-18 6:28 AM, Honnappa Nagarahalli wrote: > rte_ring implementation is not preemptible only under certain > circumstances. This clarification is helpful for data plane and > control plane communication using rte_ring. > > Signed-off-by: Honnappa Nagarahalli <honnappa.nagaraha...@arm.com> > Reviewed-by: Gavin Hu <gavin...@arm.com> > Reviewed-by: Ola Liljedahl <ola.liljed...@arm.com> > --- > v2: > * Fixed checkpatch warnings > > lib/librte_ring/rte_ring.h | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > > diff --git a/lib/librte_ring/rte_ring.h b/lib/librte_ring/rte_ring.h > index d3d3f7f..2f9c945 100644 > --- a/lib/librte_ring/rte_ring.h > +++ b/lib/librte_ring/rte_ring.h > @@ -26,8 +26,13 @@ > * - Bulk dequeue. > * - Bulk enqueue. > * > - * Note: the ring implementation is not preemptable. A lcore must not > - * be interrupted by another task that uses the same ring. > + * Note: the ring implementation can block threads from completing > + their > + * operation under the following circumstances. > + * A preempted thread can block other threads (operating on the same > + ring) > + * from completing their operations, only if those threads are > + performing > + * the same ring operation (enqueue/dequeue) as the preempted thread. > + * In other words, a preempted consumer thread will not block any > + producer > + * threads and vice versa. > * > */ > > Similar clarification is already present in Programmer's Guide for rte_ring section. Perhaps it would be good to reference it here? -- Thanks, Anatoly IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
