[dpdk-dev] [PATCH] Added Spinlock to l3fwd-vf example to prevent race conditioning

[Thomas Monjalon]

Hi Daniel,

This old patch is probably good but I'd like you explain it please.
Reviewers are also welcome.

Thanks
-- 
Thomas

2014-07-23 10:33, Thomas Monjalon:
> Hi Daniel,
> 
> Some explanations are missing here.
> 
> > Signed-off-by: Daniel Mrzyglod 
> > 
> > --- a/examples/l3fwd-vf/main.c
> > +++ b/examples/l3fwd-vf/main.c
> > @@ -54,6 +54,7 @@
> >  #include 
> >  #include 
> >  #include 
> > +#include 
> >  #include 
> >  #include 
> >  #include 
> > @@ -328,7 +329,7 @@ struct lcore_conf {
> >  } __rte_cache_aligned;
> >  
> >  static struct lcore_conf lcore_conf[RTE_MAX_LCORE];
> > -
> > +static rte_spinlock_t 
> > spinlock_conf[RTE_MAX_ETHPORTS]={RTE_SPINLOCK_INITIALIZER};
> >  /* Send burst of packets on an output interface */
> >  static inline int
> >  send_burst(struct lcore_conf *qconf, uint16_t n, uint8_t port)
> > @@ -340,7 +341,10 @@ send_burst(struct lcore_conf *qconf, uint16_t n, 
> > uint8_t port)
> > queueid = qconf->tx_queue_id;
> > m_table = (struct rte_mbuf **)qconf->tx_mbufs[port].m_table;
> >  
> > +   rte_spinlock_lock(_conf[port]) ;
> > ret = rte_eth_tx_burst(port, queueid, m_table, n);
> > +   rte_spinlock_unlock(_conf[port]);
> > +   
> > if (unlikely(ret < n)) {
> > do {
> > rte_pktmbuf_free(m_table[ret]);
> > 

[dpdk-dev] [PATCH] Added Spinlock to l3fwd-vf example to prevent race conditioning

[Xie, Huawei]

> -Original Message-
> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Thomas Monjalon
> Sent: Tuesday, November 11, 2014 3:57 PM
> To: Mrzyglod, DanielX T
> Cc: dev at dpdk.org
> Subject: Re: [dpdk-dev] [PATCH] Added Spinlock to l3fwd-vf example to prevent
> race conditioning
> 
> Hi Daniel,
> 
> This old patch is probably good but I'd like you explain it please.
> Reviewers are also welcome.
> 
> Thanks
> --
> Thomas
> 
> 2014-07-23 10:33, Thomas Monjalon:
> > Hi Daniel,
> >
> > Some explanations are missing here.
> >
> > > Signed-off-by: Daniel Mrzyglod 
> > >
> > > --- a/examples/l3fwd-vf/main.c
> > > +++ b/examples/l3fwd-vf/main.c
> > > @@ -54,6 +54,7 @@
> > >  #include 
> > >  #include 
> > >  #include 
> > > +#include 
> > >  #include 
> > >  #include 
> > >  #include 
> > > @@ -328,7 +329,7 @@ struct lcore_conf {
> > >  } __rte_cache_aligned;
> > >
> > >  static struct lcore_conf lcore_conf[RTE_MAX_LCORE];
> > > -
> > > +static rte_spinlock_t
> spinlock_conf[RTE_MAX_ETHPORTS]={RTE_SPINLOCK_INITIALIZER};
> > >  /* Send burst of packets on an output interface */
> > >  static inline int
> > >  send_burst(struct lcore_conf *qconf, uint16_t n, uint8_t port)
> > > @@ -340,7 +341,10 @@ send_burst(struct lcore_conf *qconf, uint16_t n,
> uint8_t port)
> > >   queueid = qconf->tx_queue_id;
> > >   m_table = (struct rte_mbuf **)qconf->tx_mbufs[port].m_table;
> > >
> > > + rte_spinlock_lock(_conf[port]) ;
> > >   ret = rte_eth_tx_burst(port, queueid, m_table, n);
> > > + rte_spinlock_unlock(_conf[port]);

It might not be good choice for here, but how about we also provide 
spin_trylock as alternative API?

> > > +
> > >   if (unlikely(ret < n)) {
> > >   do {
> > >   rte_pktmbuf_free(m_table[ret]);
> > >

[dpdk-dev] [PATCH] Added Spinlock to l3fwd-vf example to prevent race conditioning

[Daniel Mrzyglod]

Signed-off-by: Daniel Mrzyglod 
---
 examples/l3fwd-vf/main.c |6 +-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/examples/l3fwd-vf/main.c b/examples/l3fwd-vf/main.c
index 2ca5c21..57852d0 100644
--- a/examples/l3fwd-vf/main.c
+++ b/examples/l3fwd-vf/main.c
@@ -54,6 +54,7 @@
 #include 
 #include 
 #include 
+#include 
 #include 
 #include 
 #include 
@@ -328,7 +329,7 @@ struct lcore_conf {
 } __rte_cache_aligned;

 static struct lcore_conf lcore_conf[RTE_MAX_LCORE];
-
+static rte_spinlock_t 
spinlock_conf[RTE_MAX_ETHPORTS]={RTE_SPINLOCK_INITIALIZER};
 /* Send burst of packets on an output interface */
 static inline int
 send_burst(struct lcore_conf *qconf, uint16_t n, uint8_t port)
@@ -340,7 +341,10 @@ send_burst(struct lcore_conf *qconf, uint16_t n, uint8_t 
port)
queueid = qconf->tx_queue_id;
m_table = (struct rte_mbuf **)qconf->tx_mbufs[port].m_table;

+   rte_spinlock_lock(_conf[port]) ;
ret = rte_eth_tx_burst(port, queueid, m_table, n);
+   rte_spinlock_unlock(_conf[port]);
+   
if (unlikely(ret < n)) {
do {
rte_pktmbuf_free(m_table[ret]);
-- 
1.7.9.5