From: Joyce Kong <joyce.kong@arm.com>
Date: Wed, 13 Oct 2021 18:54:01 +0000 (-0500)
Subject: examples/multi_process: use compiler atomics for sync
X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=9b882c5b87872b6c00c7bb2d4bba7191be8648fa;p=dpdk.git

examples/multi_process: use compiler atomics for sync

Convert rte_atomic32_test_and_set usage to compiler atomic
CAS operation for display_stats sync.

Signed-off-by: Joyce Kong <joyce.kong@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
---

diff --git a/examples/multi_process/client_server_mp/mp_server/main.c b/examples/multi_process/client_server_mp/mp_server/main.c
index 9bcee460fd..b4761ebc7b 100644
--- a/examples/multi_process/client_server_mp/mp_server/main.c
+++ b/examples/multi_process/client_server_mp/mp_server/main.c
@@ -20,7 +20,6 @@
 #include <rte_per_lcore.h>
 #include <rte_lcore.h>
 #include <rte_branch_prediction.h>
-#include <rte_atomic.h>
 #include <rte_ring.h>
 #include <rte_log.h>
 #include <rte_debug.h>
@@ -158,10 +157,12 @@ static int
 sleep_lcore(__rte_unused void *dummy)
 {
 	/* Used to pick a display thread - static, so zero-initialised */
-	static rte_atomic32_t display_stats;
+	static uint32_t display_stats;
 
+	uint32_t status = 0;
 	/* Only one core should display stats */
-	if (rte_atomic32_test_and_set(&display_stats)) {
+	if (__atomic_compare_exchange_n(&display_stats, &status, 1, 0,
+			__ATOMIC_RELAXED, __ATOMIC_RELAXED)) {
 		const unsigned sleeptime = 1;
 		printf("Core %u displaying statistics\n", rte_lcore_id());