From: Phil Yang <phil.yang@arm.com>
To: dev@dpdk.org
Cc: jerin.jacob@caviumnetworks.com, Gavin.Hu@arm.com,
Honnappa.Nagarahalli@arm.com, Ola.Liljedahl@arm.com,
ferruh.yigit@intel.com, phil.yang@arm.com
Subject: [dpdk-dev] [PATCH v3 2/4] kni: fix kni fifo synchronization
Date: Mon, 8 Oct 2018 17:11:44 +0800 [thread overview]
Message-ID: <1538989906-8349-2-git-send-email-phil.yang@arm.com> (raw)
In-Reply-To: <1538989906-8349-1-git-send-email-phil.yang@arm.com>
With existing code in kni_fifo_put, rx_q values are not being updated
before updating fifo_write. While reading rx_q in kni_net_rx_normal,
This is causing the sync issue on other core. The same situation happens
in kni_fifo_get as well.
So syncing the values by adding memory barriers to make sure the values
being synced before updating fifo_write and fifo_read.
Fixes: 3fc5ca2 ("kni: initial import")
Signed-off-by: Phil Yang <phil.yang@arm.com>
Reviewed-by: Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>
Reviewed-by: Gavin Hu <Gavin.Hu@arm.com>
Reviewed-by: Ola Liljedahl <Ola.Liljedahl@arm.com>
Reviewed-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
---
lib/librte_kni/rte_kni_fifo.h | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/lib/librte_kni/rte_kni_fifo.h b/lib/librte_kni/rte_kni_fifo.h
index ac26a8c..70ac14e 100644
--- a/lib/librte_kni/rte_kni_fifo.h
+++ b/lib/librte_kni/rte_kni_fifo.h
@@ -28,8 +28,9 @@ kni_fifo_put(struct rte_kni_fifo *fifo, void **data, unsigned num)
{
unsigned i = 0;
unsigned fifo_write = fifo->write;
- unsigned fifo_read = fifo->read;
unsigned new_write = fifo_write;
+ rte_smp_rmb();
+ unsigned fifo_read = fifo->read;
for (i = 0; i < num; i++) {
new_write = (new_write + 1) & (fifo->len - 1);
@@ -39,6 +40,7 @@ kni_fifo_put(struct rte_kni_fifo *fifo, void **data, unsigned num)
fifo->buffer[fifo_write] = data[i];
fifo_write = new_write;
}
+ rte_smp_wmb();
fifo->write = fifo_write;
return i;
}
@@ -51,7 +53,9 @@ kni_fifo_get(struct rte_kni_fifo *fifo, void **data, unsigned num)
{
unsigned i = 0;
unsigned new_read = fifo->read;
+ rte_smp_rmb();
unsigned fifo_write = fifo->write;
+
for (i = 0; i < num; i++) {
if (new_read == fifo_write)
break;
@@ -59,6 +63,7 @@ kni_fifo_get(struct rte_kni_fifo *fifo, void **data, unsigned num)
data[i] = fifo->buffer[new_read];
new_read = (new_read + 1) & (fifo->len - 1);
}
+ rte_smp_rmb();
fifo->read = new_read;
return i;
}
@@ -69,5 +74,8 @@ kni_fifo_get(struct rte_kni_fifo *fifo, void **data, unsigned num)
static inline uint32_t
kni_fifo_count(struct rte_kni_fifo *fifo)
{
- return (fifo->len + fifo->write - fifo->read) & (fifo->len - 1);
+ unsigned fifo_write = fifo->write;
+ rte_smp_rmb();
+ unsigned fifo_read = fifo->read;
+ return (fifo->len + fifo_write - fifo_read) & (fifo->len - 1);
}
--
2.7.4
next prev parent reply other threads:[~2018-10-08 9:11 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-09-19 13:30 [dpdk-dev] [PATCH 1/3] config: use one single config option for C11 memory model Phil Yang
2018-09-19 13:30 ` [dpdk-dev] [PATCH 2/3] kni: fix kni fifo synchronization Phil Yang
2018-09-19 13:30 ` [dpdk-dev] [PATCH 3/3] kni: fix kni kernel " Phil Yang
2018-09-19 13:42 ` [dpdk-dev] [PATCH v2 1/3] config: use one single config option for C11 memory model Phil Yang
2018-09-19 13:42 ` [dpdk-dev] [PATCH v2 2/3] kni: fix kni fifo synchronization Phil Yang
2018-09-20 8:28 ` Jerin Jacob
2018-09-20 15:20 ` Honnappa Nagarahalli
2018-09-20 15:37 ` Jerin Jacob
2018-09-21 5:48 ` Honnappa Nagarahalli
2018-09-21 5:55 ` Jerin Jacob
2018-09-21 6:37 ` Honnappa Nagarahalli
2018-09-21 9:00 ` Phil Yang (Arm Technology China)
2018-09-25 4:44 ` Honnappa Nagarahalli
2018-09-26 11:42 ` Ferruh Yigit
2018-09-27 9:06 ` Phil Yang (Arm Technology China)
2018-09-26 11:45 ` Ferruh Yigit
2018-10-01 4:52 ` Honnappa Nagarahalli
2018-09-19 13:42 ` [dpdk-dev] [PATCH v2 3/3] kni: fix kni kernel " Phil Yang
2018-09-20 8:21 ` [dpdk-dev] [PATCH v2 1/3] config: use one single config option for C11 memory model Jerin Jacob
2018-10-08 9:11 ` [dpdk-dev] [PATCH v3 1/4] " Phil Yang
2018-10-08 9:11 ` Phil Yang [this message]
2018-10-08 21:53 ` [dpdk-dev] [PATCH v3 2/4] kni: fix kni fifo synchronization Stephen Hemminger
2018-10-10 9:58 ` Phil Yang (Arm Technology China)
2018-10-10 10:06 ` Gavin Hu (Arm Technology China)
2018-10-10 14:42 ` Ferruh Yigit
2018-10-08 9:11 ` [dpdk-dev] [PATCH v3 3/4] kni: fix kni kernel " Phil Yang
2018-10-08 9:11 ` [dpdk-dev] [PATCH v3 4/4] kni: introduce c11 atomic into kni " Phil Yang
2018-10-10 14:48 ` [dpdk-dev] [PATCH v3 1/4] config: use one single config option for C11 memory model Ferruh Yigit
2018-10-12 9:17 ` Phil Yang (Arm Technology China)
2018-10-26 15:56 ` Thomas Monjalon
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