Replace rte_smp_wmb/rmb with rte_io_wmb/rmb as they are the same on x86
and ppc platforms. Then, for function virtqueue_fetch_flags_packed/
virtqueue_store_flags_packed, the if and else branch are still identical
for the platforms except Arm.
Signed-off-by: Joyce Kong <joyce.k...@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.w...@arm.com>
---
drivers/net/virtio/virtqueue.h | 27 +++++++++++++--------------
1 file changed, 13 insertions(+), 14 deletions(-)
diff --git a/drivers/net/virtio/virtqueue.h b/drivers/net/virtio/virtqueue.h
index 42c4c9882..ac3d9e750 100644
--- a/drivers/net/virtio/virtqueue.h
+++ b/drivers/net/virtio/virtqueue.h
@@ -66,16 +66,15 @@ virtqueue_fetch_flags_packed(struct vring_packed_desc *dp,
uint16_t flags;
if (weak_barriers) {
-/* x86 prefers to using rte_smp_rmb over __atomic_load_n as it reports
+/* x86 prefers to using rte_io_rmb over __atomic_load_n as it reports
* a better perf(~1.5%), which comes from the saved branch by the compiler.
- * The if and else branch are identical with the smp and io barriers both
- * defined as compiler barriers on x86.
+ * The if and else branch are identical on the platforms except Arm.
*/
-#ifdef RTE_ARCH_X86_64
- flags = dp->flags;
- rte_smp_rmb();
-#else
+#ifdef RTE_ARCH_ARM
flags = __atomic_load_n(&dp->flags, __ATOMIC_ACQUIRE);
+#else
+ flags = dp->flags;
+ rte_io_rmb();
#endif
} else {
flags = dp->flags;
@@ -90,22 +89,22 @@ virtqueue_store_flags_packed(struct vring_packed_desc *dp,
uint16_t flags, uint8_t weak_barriers)
{
if (weak_barriers) {
-/* x86 prefers to using rte_smp_wmb over __atomic_store_n as it reports
+/* x86 prefers to using rte_io_wmb over __atomic_store_n as it reports
* a better perf(~1.5%), which comes from the saved branch by the compiler.
- * The if and else branch are identical with the smp and io barriers both
- * defined as compiler barriers on x86.
+ * The if and else branch are identical on the platforms except Arm.
*/
-#ifdef RTE_ARCH_X86_64
- rte_smp_wmb();
- dp->flags = flags;
-#else
+#ifdef RTE_ARCH_ARM
__atomic_store_n(&dp->flags, flags, __ATOMIC_RELEASE);
+#else
+ rte_io_wmb();
+ dp->flags = flags;
#endif
} else {
rte_io_wmb();
dp->flags = flags;
}
}
+
#ifdef RTE_PMD_PACKET_PREFETCH
#define rte_packet_prefetch(p) rte_prefetch1(p)
#else
--
2.29.2
