Re: [Qemu-devel] [PATCH v5 7/7] qmp-event: add event notification for memory hot unplug error

[Zhu Guihua]

On 03/27/2015 10:53 PM, Eric Blake wrote:

On 03/27/2015 03:20 AM, Zhu Guihua wrote:

When memory hot unplug fails, this patch adds support to send
QMP event to notify mgmt about this failure.

Signed-off-by: Zhu Guihua <zhugh.f...@cn.fujitsu.com>
---
  docs/qmp/qmp-events.txt  | 17 +++++++++++++++++
  hw/acpi/memory_hotplug.c |  8 +++++++-
  monitor.c                |  1 +
  qapi/event.json          | 14 ++++++++++++++
  4 files changed, 39 insertions(+), 1 deletion(-)

diff --git a/docs/qmp/qmp-events.txt b/docs/qmp/qmp-events.txt
index d759d19..7a05705 100644
--- a/docs/qmp/qmp-events.txt
+++ b/docs/qmp/qmp-events.txt
@@ -226,6 +226,23 @@ Example:
  { "event": "GUEST_PANICKED",
       "data": { "action": "pause" } }

+MEM_HOT_UNPLUG_ERROR

+--------------------
+Emitted when memory hot unplug occurs error.

s/occurs error/error occurs/

+
+Data:
+
+- "device": device name (json-string)
+- "msg": Informative message (e.g., reason for the error) (json-string)
+
+Example:
+
+{ "event": "MEM_HOT_UNPLUG_ERROR"
+  "data": { "device": "dimm1",
+            "msg": "acpi: device unplug for not supported device"

s/not supported/unsupported/

+  },
+  "timestamp": { "seconds": 1265044230, "microseconds": 450486 } }
+
  NIC_RX_FILTER_CHANGED
  ---------------------

diff --git a/hw/acpi/memory_hotplug.c b/hw/acpi/memory_hotplug.c

index 2a1b866..f1cef71 100644
--- a/hw/acpi/memory_hotplug.c
+++ b/hw/acpi/memory_hotplug.c
@@ -94,6 +94,7 @@ static void acpi_memory_hotplug_write(void *opaque, hwaddr 
addr, uint64_t data,
      ACPIOSTInfo *info;
      DeviceState *dev = NULL;
      HotplugHandler *hotplug_ctrl = NULL;
+    Error *local_err = NULL;

if (!mem_st->dev_count) {

          return;
@@ -148,7 +149,12 @@ static void acpi_memory_hotplug_write(void *opaque, hwaddr 
addr, uint64_t data,
              dev = DEVICE(mdev->dimm);
              hotplug_ctrl = qdev_get_hotplug_handler(dev);
              /* call pc-dimm unplug cb */
-            hotplug_handler_unplug(hotplug_ctrl, dev, NULL);
+            hotplug_handler_unplug(hotplug_ctrl, dev, &local_err);
+            if (local_err) {
+                qapi_event_send_mem_unplug_error(dev->id,
+                                                 error_get_pretty(local_err),
+                                                 &error_abort);
+            }
          }

Does this leak local_err?

Here should handle this error not to forget it.
It is a good way to send qmp event to notify mgmt.

+++ b/qapi/event.json
@@ -330,3 +330,17 @@
  ##
  { 'event': 'VSERPORT_CHANGE',
    'data': { 'id': 'str', 'open': 'bool' } }
+
+##
+# @MEM_UNPLUG_ERROR
+#
+# Emitted when memory hot unplug occurs error.

s/occurs error/error occurs/

+#
+# @device: device name
+#
+# @msg: Informative message
+#
+# Since: 2.3

You're awfully late for 2.3; this may need to be 2.4.

Got it, thanks.

Regards,
Zhu

+##
+{ 'event': 'MEM_UNPLUG_ERROR',
+  'data': { 'device': 'str', 'msg': 'str' } }