Merge remote-tracking branch 'remotes/huth-gitlab/tags/pull-request-2020-09-16' into staging

* Fix "readlink -f" problem in iotests on macOS (to fix the Cirrus-CI tests)
* Some minor qtest improvements
* Fix the unit tests to work on MSYS2, too
* Enable building and testing on MSYS2 in the Cirrus-CI
* Build FreeBSD with one task again in the Cirrus-CI

# gpg: Signature made Wed 16 Sep 2020 12:24:29 BST
# gpg:                using RSA key 27B88847EEE0250118F3EAB92ED9D774FE702DB5
# gpg:                issuer "thuth@redhat.com"
# gpg: Good signature from "Thomas Huth <th.huth@gmx.de>" [full]
# gpg:                 aka "Thomas Huth <thuth@redhat.com>" [full]
# gpg:                 aka "Thomas Huth <huth@tuxfamily.org>" [full]
# gpg:                 aka "Thomas Huth <th.huth@posteo.de>" [unknown]
# Primary key fingerprint: 27B8 8847 EEE0 2501 18F3  EAB9 2ED9 D774 FE70 2DB5

* remotes/huth-gitlab/tags/pull-request-2020-09-16: (24 commits)
  cirrus: Building freebsd in a single shot
  ci: Enable msys2 ci in cirrus
  tests: Fixes test-qdev-global-props.c
  tests: fix test-util-sockets.c
  tests: Fixes test-io-channel-file by mask only owner file state mask bits
  tests: fixes aio-win32 about aio_remove_fd_handler, get it consistence with aio-posix.c
  tests: Fixes test-io-channel-socket.c tests under msys2/mingw
  vmstate: Fixes test-vmstate.c on msys2/mingw
  meson: remove empty else and duplicated gio deps
  meson: Use -b to ignore CR vs. CR-LF issues on Windows
  osdep: file locking functions are not available on Win32
  tests: test-replication disable /replication/secondary/* on msys2/mingw.
  tests: Fixes test-replication.c on msys2/mingw.
  meson: disable crypto tests are empty under win32
  meson: Disable test-char on msys2/mingw for fixing tests stuck
  rcu: fixes test-logging.c by call drain_call_rcu before rmdir_full
  tests: Convert g_free to g_autofree macro in test-logging.c
  rcu: Implement drain_call_rcu
  qga/commands-win32: Fix problem with redundant protype declaration
  Simplify the .gitignore file
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

2 files changed, 65 insertions, 2 deletions

diff --git a/util/aio-win32.c b/util/aio-win32.c
index 953c56a..49bd90e 100644
--- a/util/aio-win32.c
+++ b/util/aio-win32.c
@@ -37,6 +37,16 @@ struct AioHandler {
 
 static void aio_remove_fd_handler(AioContext *ctx, AioHandler *node)
 {
+    /*
+     * If the GSource is in the process of being destroyed then
+     * g_source_remove_poll() causes an assertion failure.  Skip
+     * removal in that case, because glib cleans up its state during
+     * destruction anyway.
+     */
+    if (!g_source_is_destroyed(&ctx->source)) {
+        g_source_remove_poll(&ctx->source, &node->pfd);
+    }
+
     /* If aio_poll is in progress, just mark the node as deleted */
     if (qemu_lockcnt_count(&ctx->list_lock)) {
         node->deleted = 1;
@@ -139,8 +149,6 @@ void aio_set_event_notifier(AioContext *ctx,
     /* Are we deleting the fd handler? */
     if (!io_notify) {
         if (node) {
-            g_source_remove_poll(&ctx->source, &node->pfd);
-
             aio_remove_fd_handler(ctx, node);
         }
     } else {
diff --git a/util/rcu.c b/util/rcu.c
index 60a37f7..c4fefa9 100644
--- a/util/rcu.c
+++ b/util/rcu.c
@@ -293,6 +293,61 @@ void call_rcu1(struct rcu_head *node, void (*func)(struct rcu_head *node))
     qemu_event_set(&rcu_call_ready_event);
 }
 
+
+struct rcu_drain {
+    struct rcu_head rcu;
+    QemuEvent drain_complete_event;
+};
+
+static void drain_rcu_callback(struct rcu_head *node)
+{
+    struct rcu_drain *event = (struct rcu_drain *)node;
+    qemu_event_set(&event->drain_complete_event);
+}
+
+/*
+ * This function ensures that all pending RCU callbacks
+ * on the current thread are done executing
+
+ * drops big qemu lock during the wait to allow RCU thread
+ * to process the callbacks
+ *
+ */
+
+void drain_call_rcu(void)
+{
+    struct rcu_drain rcu_drain;
+    bool locked = qemu_mutex_iothread_locked();
+
+    memset(&rcu_drain, 0, sizeof(struct rcu_drain));
+    qemu_event_init(&rcu_drain.drain_complete_event, false);
+
+    if (locked) {
+        qemu_mutex_unlock_iothread();
+    }
+
+
+    /*
+     * RCU callbacks are invoked in the same order as in which they
+     * are registered, thus we can be sure that when 'drain_rcu_callback'
+     * is called, all RCU callbacks that were registered on this thread
+     * prior to calling this function are completed.
+     *
+     * Note that since we have only one global queue of the RCU callbacks,
+     * we also end up waiting for most of RCU callbacks that were registered
+     * on the other threads, but this is a side effect that shoudn't be
+     * assumed.
+     */
+
+    call_rcu1(&rcu_drain.rcu, drain_rcu_callback);
+    qemu_event_wait(&rcu_drain.drain_complete_event);
+
+    if (locked) {
+        qemu_mutex_lock_iothread();
+    }
+
+}
+
 void rcu_register_thread(void)
 {
     assert(rcu_reader.ctr == 0);