Merge remote-tracking branch 'remotes/armbru/tags/pull-monitor-2020-10-09' into staging

Monitor patches for 2020-10-09

# gpg: Signature made Fri 09 Oct 2020 06:16:51 BST
# gpg:                using RSA key 354BC8B3D7EB2A6B68674E5F3870B400EB918653
# gpg:                issuer "armbru@redhat.com"
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>" [full]
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>" [full]
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-monitor-2020-10-09:
  block: Convert 'block_resize' to coroutine
  block: Add bdrv_lock()/unlock()
  block: Add bdrv_co_enter()/leave()
  util/async: Add aio_co_reschedule_self()
  hmp: Add support for coroutine command handlers
  qmp: Move dispatcher to a coroutine
  qapi: Add a 'coroutine' flag for commands
  monitor: Make current monitor a per-coroutine property
  qmp: Call monitor_set_cur() only in qmp_dispatch()
  qmp: Assert that no other monitor is active
  hmp: Update current monitor only in handle_hmp_command()
  monitor: Use getter/setter functions for cur_mon
  monitor: Add Monitor parameter to monitor_get_cpu_index()
  monitor: Add Monitor parameter to monitor_set_cpu()

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

1 files changed, 35 insertions, 9 deletions

diff --git a/monitor/hmp.c b/monitor/hmp.c
index 4ecdefd705..c5cd9d372b 100644
--- a/monitor/hmp.c
+++ b/monitor/hmp.c
@@ -1056,6 +1056,21 @@ fail:
     return NULL;
 }
 
+typedef struct HandleHmpCommandCo {
+    Monitor *mon;
+    const HMPCommand *cmd;
+    QDict *qdict;
+    bool done;
+} HandleHmpCommandCo;
+
+static void handle_hmp_command_co(void *opaque)
+{
+    HandleHmpCommandCo *data = opaque;
+    data->cmd->cmd(data->mon, data->qdict);
+    monitor_set_cur(qemu_coroutine_self(), NULL);
+    data->done = true;
+}
+
 void handle_hmp_command(MonitorHMP *mon, const char *cmdline)
 {
     QDict *qdict;
@@ -1079,7 +1094,24 @@ void handle_hmp_command(MonitorHMP *mon, const char *cmdline)
         return;
     }
 
-    cmd->cmd(&mon->common, qdict);
+    if (!cmd->coroutine) {
+        /* old_mon is non-NULL when called from qmp_human_monitor_command() */
+        Monitor *old_mon = monitor_set_cur(qemu_coroutine_self(), &mon->common);
+        cmd->cmd(&mon->common, qdict);
+        monitor_set_cur(qemu_coroutine_self(), old_mon);
+    } else {
+        HandleHmpCommandCo data = {
+            .mon = &mon->common,
+            .cmd = cmd,
+            .qdict = qdict,
+            .done = false,
+        };
+        Coroutine *co = qemu_coroutine_create(handle_hmp_command_co, &data);
+        monitor_set_cur(co, &mon->common);
+        aio_co_enter(qemu_get_aio_context(), co);
+        AIO_WAIT_WHILE(qemu_get_aio_context(), !data.done);
+    }
+
     qobject_unref(qdict);
 }
 
@@ -1300,26 +1332,20 @@ cleanup:
 
 static void monitor_read(void *opaque, const uint8_t *buf, int size)
 {
-    MonitorHMP *mon;
-    Monitor *old_mon = cur_mon;
+    MonitorHMP *mon = container_of(opaque, MonitorHMP, common);
     int i;
 
-    cur_mon = opaque;
-    mon = container_of(cur_mon, MonitorHMP, common);
-
     if (mon->rs) {
         for (i = 0; i < size; i++) {
             readline_handle_byte(mon->rs, buf[i]);
         }
     } else {
         if (size == 0 || buf[size - 1] != 0) {
-            monitor_printf(cur_mon, "corrupted command\n");
+            monitor_printf(&mon->common, "corrupted command\n");
         } else {
             handle_hmp_command(mon, (char *)buf);
         }
     }
-
-    cur_mon = old_mon;
 }
 
 static void monitor_event(void *opaque, QEMUChrEvent event)