From 1f546b709d6121d1a3e629e482ba14fb7bf10ce2 Mon Sep 17 00:00:00 2001
From: Peter Xu <peterx@redhat.com>
Date: Tue, 15 Jun 2021 13:55:23 -0400
Subject: [PATCH] tests: migration-test: Add dirty ring test

Add dirty ring test if kernel supports it.  Add the dirty ring parameter on
source should be mostly enough, but let's change the dest too to make them
match always.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210615175523.439830-3-peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 tests/qtest/migration-test.c | 58 +++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 55 insertions(+), 3 deletions(-)

diff --git a/tests/qtest/migration-test.c b/tests/qtest/migration-test.c
index 2b028df687..328d6dbe97 100644
--- a/tests/qtest/migration-test.c
+++ b/tests/qtest/migration-test.c
@@ -27,6 +27,10 @@
 #include "migration-helpers.h"
 #include "tests/migration/migration-test.h"
 
+#if defined(__linux__)
+#include "linux/kvm.h"
+#endif
+
 /* TODO actually test the results and get rid of this */
 #define qtest_qmp_discard_response(...) qobject_unref(qtest_qmp(__VA_ARGS__))
 
@@ -467,6 +471,8 @@ typedef struct {
     bool use_shmem;
     /* only launch the target process */
     bool only_target;
+    /* Use dirty ring if true; dirty logging otherwise */
+    bool use_dirty_ring;
     char *opts_source;
     char *opts_target;
 } MigrateStart;
@@ -573,11 +579,13 @@ static int test_migrate_start(QTestState **from, QTestState **to,
         shmem_opts = g_strdup("");
     }
 
-    cmd_source = g_strdup_printf("-accel kvm -accel tcg%s%s "
+    cmd_source = g_strdup_printf("-accel kvm%s -accel tcg%s%s "
                                  "-name source,debug-threads=on "
                                  "-m %s "
                                  "-serial file:%s/src_serial "
                                  "%s %s %s %s",
+                                 args->use_dirty_ring ?
+                                 ",dirty-ring-size=4096" : "",
                                  machine_opts ? " -machine " : "",
                                  machine_opts ? machine_opts : "",
                                  memory_size, tmpfs,
@@ -587,12 +595,14 @@ static int test_migrate_start(QTestState **from, QTestState **to,
         *from = qtest_init(cmd_source);
     }
 
-    cmd_target = g_strdup_printf("-accel kvm -accel tcg%s%s "
+    cmd_target = g_strdup_printf("-accel kvm%s -accel tcg%s%s "
                                  "-name target,debug-threads=on "
                                  "-m %s "
                                  "-serial file:%s/dest_serial "
                                  "-incoming %s "
                                  "%s %s %s %s",
+                                 args->use_dirty_ring ?
+                                 ",dirty-ring-size=4096" : "",
                                  machine_opts ? " -machine " : "",
                                  machine_opts ? machine_opts : "",
                                  memory_size, tmpfs, uri,
@@ -785,12 +795,14 @@ static void test_baddest(void)
     test_migrate_end(from, to, false);
 }
 
-static void test_precopy_unix(void)
+static void test_precopy_unix_common(bool dirty_ring)
 {
     g_autofree char *uri = g_strdup_printf("unix:%s/migsocket", tmpfs);
     MigrateStart *args = migrate_start_new();
     QTestState *from, *to;
 
+    args->use_dirty_ring = dirty_ring;
+
     if (test_migrate_start(&from, &to, uri, args)) {
         return;
     }
@@ -825,6 +837,18 @@ static void test_precopy_unix(void)
     test_migrate_end(from, to, true);
 }
 
+static void test_precopy_unix(void)
+{
+    /* Using default dirty logging */
+    test_precopy_unix_common(false);
+}
+
+static void test_precopy_unix_dirty_ring(void)
+{
+    /* Using dirty ring tracking */
+    test_precopy_unix_common(true);
+}
+
 #if 0
 /* Currently upset on aarch64 TCG */
 static void test_ignore_shared(void)
@@ -1369,6 +1393,29 @@ static void test_multifd_tcp_cancel(void)
     test_migrate_end(from, to2, true);
 }
 
+static bool kvm_dirty_ring_supported(void)
+{
+#if defined(__linux__)
+    int ret, kvm_fd = open("/dev/kvm", O_RDONLY);
+
+    if (kvm_fd < 0) {
+        return false;
+    }
+
+    ret = ioctl(kvm_fd, KVM_CHECK_EXTENSION, KVM_CAP_DIRTY_LOG_RING);
+    close(kvm_fd);
+
+    /* We test with 4096 slots */
+    if (ret < 4096) {
+        return false;
+    }
+
+    return true;
+#else
+    return false;
+#endif
+}
+
 int main(int argc, char **argv)
 {
     char template[] = "/tmp/migration-test-XXXXXX";
@@ -1439,6 +1486,11 @@ int main(int argc, char **argv)
     qtest_add_func("/migration/multifd/tcp/zstd", test_multifd_tcp_zstd);
 #endif
 
+    if (kvm_dirty_ring_supported()) {
+        qtest_add_func("/migration/dirty_ring",
+                       test_precopy_unix_dirty_ring);
+    }
+
     ret = g_test_run();
 
     g_assert_cmpint(ret, ==, 0);
-- 
2.11.4.GIT