qemu/0039-tests-test-thread-pool-is-racy-add-.patch

From 7ddbb37c5a0ae657ff97c221c055cb2e843016f4 Mon Sep 17 00:00:00 2001
From: Bruce Rogers <brogers@suse.com>
Date: Fri, 13 Apr 2018 11:46:47 -0600
Subject: [PATCH] tests: test-thread-pool is racy - add some barriers

I imagine there is more to be done to fix the memory consistency
races here, but these added barriers at least let it pass on ppc64le,
whereas before it would fail regularly there.

Signed-off-by: Bruce Rogers <brogers@suse.com>
---
 tests/test-thread-pool.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/tests/test-thread-pool.c b/tests/test-thread-pool.c
index 91b4ec5524..9790200df7 100644
--- a/tests/test-thread-pool.c
+++ b/tests/test-thread-pool.c
@@ -171,6 +171,7 @@ static void do_test_cancel(bool sync)
     /* Cancel the jobs that haven't been started yet.  */
     num_canceled = 0;
     for (i = 0; i < 100; i++) {
+	smp_mb();
         if (atomic_cmpxchg(&data[i].n, 0, 3) == 0) {
             data[i].ret = -ECANCELED;
             if (sync) {
@@ -185,6 +186,7 @@ static void do_test_cancel(bool sync)
     g_assert_cmpint(num_canceled, <, 100);
 
     for (i = 0; i < 100; i++) {
+	smp_mb();
         if (data[i].aiocb && data[i].n != 3) {
             if (sync) {
                 /* Canceling the others will be a blocking operation.  */
@@ -201,6 +203,7 @@ static void do_test_cancel(bool sync)
     }
     g_assert_cmpint(active, ==, 0);
     for (i = 0; i < 100; i++) {
+	smp_mb();
         if (data[i].n == 3) {
             g_assert_cmpint(data[i].ret, ==, -ECANCELED);
             g_assert(data[i].aiocb == NULL);