[dpdk-dev] [PATCH v7] eal/arm64: fix rdtsc precise version

[Linhaifeng]

In order to get more accurate the cntvct_el0 reading,
SW must invoke isb.

Fixes: ccad39ea0712 ("eal/arm: add cpu cycle operations for ARMv8")
Cc: stable at dpdk.org

Reviewed-by: David Marchand <david.marchand at redhat.com>
Reviewed-by: Jerin Jacob <jerinjacobk at gmail.com>
Reviewed-by: Gavin Hu <gavin.hu at arm.com>
Signed-off-by: Haifeng Lin <haifeng.lin at huawei.com>
---
 lib/librte_eal/common/include/arch/arm/rte_cycles_64.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/librte_eal/common/include/arch/arm/rte_cycles_64.h b/lib/librte_eal/common/include/arch/arm/rte_cycles_64.h
index 68e7c7338..da557b6a1 100644
--- a/lib/librte_eal/common/include/arch/arm/rte_cycles_64.h
+++ b/lib/librte_eal/common/include/arch/arm/rte_cycles_64.h
@@ -62,7 +62,7 @@ rte_rdtsc(void)
 static inline uint64_t
 rte_rdtsc_precise(void)
 {
-	rte_mb();
+	asm volatile("isb" : : : "memory");
 	return rte_rdtsc();
 }
 
-- 
2.24.1.windows.2