On Mon, 31 Oct 2016 17:52:24 +0800
Xiao Guangrong <address@hidden> wrote:
On 10/31/2016 05:45 PM, Igor Mammedov wrote:
On Sun, 30 Oct 2016 23:25:05 +0200
"Michael S. Tsirkin" <address@hidden> wrote:
From: Xiao Guangrong <address@hidden>
The buffer is used to save the FIT info for all the presented nvdimm
devices which is updated after the nvdimm device is plugged or
unplugged. In the later patch, it will be used to construct NVDIMM
ACPI _FIT method which reflects the presented nvdimm devices after
nvdimm hotplug
As FIT buffer can not completely mapped into guest address space,
OSPM will exit to QEMU multiple times, however, there is the race
condition - FIT may be changed during these multiple exits, so that
some rules are introduced:
1) the user should hold the @lock to access the buffer and
Could you explain why lock is needed?
2) mark @dirty whenever the buffer is updated.
@dirty is cleared for the first time OSPM gets fit buffer, if
dirty is detected in the later access, OSPM will restart the
access
As fit should be updated after nvdimm device is successfully realized
so that a new hotplug callback, post_hotplug, is introduced
Signed-off-by: Xiao Guangrong <address@hidden>
Reviewed-by: Michael S. Tsirkin <address@hidden>
Signed-off-by: Michael S. Tsirkin <address@hidden>
---
include/hw/hotplug.h | 10 +++++++++
include/hw/mem/nvdimm.h | 26 +++++++++++++++++++++-
hw/acpi/nvdimm.c | 59 +++++++++++++++++++++++++++++++++++--------------
hw/core/hotplug.c | 11 +++++++++
hw/core/qdev.c | 20 +++++++++++++----
hw/i386/acpi-build.c | 2 +-
hw/i386/pc.c | 19 ++++++++++++++++
7 files changed, 124 insertions(+), 23 deletions(-)
diff --git a/include/hw/hotplug.h b/include/hw/hotplug.h
index c0db869..10ca5b6 100644
--- a/include/hw/hotplug.h
+++ b/include/hw/hotplug.h
@@ -47,6 +47,7 @@ typedef void (*hotplug_fn)(HotplugHandler *plug_handler,
* @parent: Opaque parent interface.
* @pre_plug: pre plug callback called at start of device.realize(true)
* @plug: plug callback called at end of device.realize(true).
+ * @post_pug: post plug callback called after device is successfully plugged.
this doesn't seem to be necessary,
why hotplug_handler_plug() isn't sufficient?
At the point of hotplug_handler_plug(), the device is not realize (realized ==
0),
however, nvdimm_get_plugged_device_list() works on realized nvdimm devices.
I suggest instead of adding redundant hook, to reuse hotplug_handler_plug()
which is called after device::realize() successfully completed and amend
nvdimm_plugged_device_list() as follow:
diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c
index e486128..c6d8cbb 100644
--- a/hw/acpi/nvdimm.c
+++ b/hw/acpi/nvdimm.c
@@ -38,11 +38,7 @@ static int nvdimm_plugged_device_list(Object *obj, void
*opaque)
GSList **list = opaque;
if (object_dynamic_cast(obj, TYPE_NVDIMM)) {
- DeviceState *dev = DEVICE(obj);
-
- if (dev->realized) { /* only realized NVDIMMs matter */
- *list = g_slist_append(*list, DEVICE(obj));
- }
+ *list = g_slist_append(*list, obj);
}
object_child_foreach(obj, nvdimm_plugged_device_list, opaque);
that should count not only already present nvdimms but also the one that's
being hotplugged.