From: Phil Yang <phil.yang@arm.com>
To: dev@dpdk.org
Cc: nd@arm.com, jerin.jacob@caviumnetworks.com,
kkokkilagadda@caviumnetworks.com, Honnappa.Nagarahalli@arm.com,
Gavin.Hu@arm.com
Subject: [dpdk-dev] [PATCH v2 3/3] kni: fix kni kernel fifo synchronization
Date: Wed, 19 Sep 2018 21:42:40 +0800 [thread overview]
Message-ID: <1537364560-4124-3-git-send-email-phil.yang@arm.com> (raw)
In-Reply-To: <1537364560-4124-1-git-send-email-phil.yang@arm.com>
Adding memory barrier to make sure the values being synced
before updating fifo_write in kni_fifo_put and fifo_read in
kni_fifo_get.
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>
---
kernel/linux/kni/kni_fifo.h | 16 ++++++++++------
.../linuxapp/eal/include/exec-env/rte_kni_common.h | 1 +
2 files changed, 11 insertions(+), 6 deletions(-)
diff --git a/kernel/linux/kni/kni_fifo.h b/kernel/linux/kni/kni_fifo.h
index 9a4762d..2cb3a4a 100644
--- a/kernel/linux/kni/kni_fifo.h
+++ b/kernel/linux/kni/kni_fifo.h
@@ -16,7 +16,7 @@ kni_fifo_put(struct rte_kni_fifo *fifo, void **data, uint32_t num)
{
uint32_t i = 0;
uint32_t fifo_write = fifo->write;
- uint32_t fifo_read = fifo->read;
+ uint32_t fifo_read = smp_load_acquire(&fifo->read);
uint32_t new_write = fifo_write;
for (i = 0; i < num; i++) {
@@ -27,7 +27,7 @@ kni_fifo_put(struct rte_kni_fifo *fifo, void **data, uint32_t num)
fifo->buffer[fifo_write] = data[i];
fifo_write = new_write;
}
- fifo->write = fifo_write;
+ smp_store_release(&fifo->write, fifo_write);
return i;
}
@@ -40,7 +40,7 @@ kni_fifo_get(struct rte_kni_fifo *fifo, void **data, uint32_t num)
{
uint32_t i = 0;
uint32_t new_read = fifo->read;
- uint32_t fifo_write = fifo->write;
+ uint32_t fifo_write = smp_load_acquire(&fifo->write);
for (i = 0; i < num; i++) {
if (new_read == fifo_write)
@@ -49,7 +49,7 @@ kni_fifo_get(struct rte_kni_fifo *fifo, void **data, uint32_t num)
data[i] = fifo->buffer[new_read];
new_read = (new_read + 1) & (fifo->len - 1);
}
- fifo->read = new_read;
+ smp_store_release(&fifo->read, new_read);
return i;
}
@@ -60,7 +60,9 @@ kni_fifo_get(struct rte_kni_fifo *fifo, void **data, uint32_t num)
static inline uint32_t
kni_fifo_count(struct rte_kni_fifo *fifo)
{
- return (fifo->len + fifo->write - fifo->read) & (fifo->len - 1);
+ uint32_t fifo_write = smp_load_acquire(&fifo->write);
+ uint32_t fifo_read = smp_load_acquire(&fifo->read);
+ return (fifo->len + fifo_write - fifo_read) & (fifo->len - 1);
}
/**
@@ -69,7 +71,9 @@ kni_fifo_count(struct rte_kni_fifo *fifo)
static inline uint32_t
kni_fifo_free_count(struct rte_kni_fifo *fifo)
{
- return (fifo->read - fifo->write - 1) & (fifo->len - 1);
+ uint32_t fifo_write = smp_load_acquire(&fifo->write);
+ uint32_t fifo_read = smp_load_acquire(&fifo->read);
+ return (fifo_read - fifo_write - 1) & (fifo->len - 1);
}
#endif /* _KNI_FIFO_H_ */
diff --git a/lib/librte_eal/linuxapp/eal/include/exec-env/rte_kni_common.h b/lib/librte_eal/linuxapp/eal/include/exec-env/rte_kni_common.h
index 1fd713b..5902ae4 100644
--- a/lib/librte_eal/linuxapp/eal/include/exec-env/rte_kni_common.h
+++ b/lib/librte_eal/linuxapp/eal/include/exec-env/rte_kni_common.h
@@ -8,6 +8,7 @@
#ifdef __KERNEL__
#include <linux/if.h>
+#include <asm/barrier.h>
#define RTE_STD_C11
#else
#include <rte_common.h>
--
2.7.4
next prev parent reply other threads:[~2018-09-19 13:44 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 ` Phil Yang [this message]
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 ` [dpdk-dev] [PATCH v3 2/4] kni: fix kni fifo synchronization Phil Yang
2018-10-08 21:53 ` 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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