Re: [PATCH 01/10] libvirt: add stateShutdown/stateShutdownWait to drivers

[Daniel P . Berrangé]

On Tue, Jul 14, 2020 at 12:32:52PM +0300, Nikolay Shirokovskiy wrote:
> stateShutdown is supposed to inform driver that it will be closed soon so that
> the driver can prepare and finish all background threads quickly on
> stateShutdownWait call.
> 
> Signed-off-by: Nikolay Shirokovskiy 
> ---
>  scripts/check-drivername.py |  2 ++
>  src/driver-state.h  |  8 
>  src/libvirt.c   | 42 ++
>  src/libvirt_internal.h  |  2 ++
>  4 files changed, 54 insertions(+)
> 
> diff --git a/scripts/check-drivername.py b/scripts/check-drivername.py
> index 39eff83..19d1cd1 100644
> --- a/scripts/check-drivername.py
> +++ b/scripts/check-drivername.py
> @@ -50,6 +50,8 @@ for drvfile in drvfiles:
>  "virDrvStateCleanup",
>  "virDrvStateReload",
>  "virDrvStateStop",
> +"virDrvStateShutdown",
> +"virDrvStateShutdownWait",
>  "virDrvConnectSupportsFeature",
>  "virDrvConnectURIProbe",
>  "virDrvDomainMigratePrepare",
> diff --git a/src/driver-state.h b/src/driver-state.h
> index 6b3f501..1f664f3 100644
> --- a/src/driver-state.h
> +++ b/src/driver-state.h
> @@ -45,6 +45,12 @@ typedef int
>  typedef int
>  (*virDrvStateStop)(void);
>  
> +typedef int
> +(*virDrvStateShutdown)(void);
> +
> +typedef int
> +(*virDrvStateShutdownWait)(void);

This is a bit of a bikeshedding comment, but I would have called
them   "StateShutdownPrepare" and "StateShutdownComplete" (or Wait)
just to make it slightly clearer that the first method is just
intended to kick off a shutdown asynchronously.

The design overall looks fine though, so regardless of the name

Reviewed-by: Daniel P. Berrangé 


Regards,
Daniel
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[PATCH 01/10] libvirt: add stateShutdown/stateShutdownWait to drivers

[Nikolay Shirokovskiy]

stateShutdown is supposed to inform driver that it will be closed soon so that
the driver can prepare and finish all background threads quickly on
stateShutdownWait call.

Signed-off-by: Nikolay Shirokovskiy 
---
 scripts/check-drivername.py |  2 ++
 src/driver-state.h  |  8 
 src/libvirt.c   | 42 ++
 src/libvirt_internal.h  |  2 ++
 4 files changed, 54 insertions(+)

diff --git a/scripts/check-drivername.py b/scripts/check-drivername.py
index 39eff83..19d1cd1 100644
--- a/scripts/check-drivername.py
+++ b/scripts/check-drivername.py
@@ -50,6 +50,8 @@ for drvfile in drvfiles:
 "virDrvStateCleanup",
 "virDrvStateReload",
 "virDrvStateStop",
+"virDrvStateShutdown",
+"virDrvStateShutdownWait",
 "virDrvConnectSupportsFeature",
 "virDrvConnectURIProbe",
 "virDrvDomainMigratePrepare",
diff --git a/src/driver-state.h b/src/driver-state.h
index 6b3f501..1f664f3 100644
--- a/src/driver-state.h
+++ b/src/driver-state.h
@@ -45,6 +45,12 @@ typedef int
 typedef int
 (*virDrvStateStop)(void);
 
+typedef int
+(*virDrvStateShutdown)(void);
+
+typedef int
+(*virDrvStateShutdownWait)(void);
+
 typedef struct _virStateDriver virStateDriver;
 typedef virStateDriver *virStateDriverPtr;
 
@@ -55,4 +61,6 @@ struct _virStateDriver {
 virDrvStateCleanup stateCleanup;
 virDrvStateReload stateReload;
 virDrvStateStop stateStop;
+virDrvStateShutdown stateShutdown;
+virDrvStateShutdownWait stateShutdownWait;
 };
diff --git a/src/libvirt.c b/src/libvirt.c
index b2d0ba3..28f9332 100644
--- a/src/libvirt.c
+++ b/src/libvirt.c
@@ -673,6 +673,48 @@ virStateInitialize(bool privileged,
 
 
 /**
+ * virStateShutdown:
+ *
+ * Run each virtualization driver's shutdown method.
+ *
+ * Returns 0 if all succeed, -1 upon any failure.
+ */
+int
+virStateShutdown(void)
+{
+size_t i;
+
+for (i = 0; i < virStateDriverTabCount; i++) {
+if (virStateDriverTab[i]->stateShutdown &&
+virStateDriverTab[i]->stateShutdown() < 0)
+return -1;
+}
+return 0;
+}
+
+
+/**
+ * virStateShutdownWait:
+ *
+ * Run each virtualization driver's shutdown wait method.
+ *
+ * Returns 0 if all succeed, -1 upon any failure.
+ */
+int
+virStateShutdownWait(void)
+{
+size_t i;
+
+for (i = 0; i < virStateDriverTabCount; i++) {
+if (virStateDriverTab[i]->stateShutdownWait &&
+virStateDriverTab[i]->stateShutdownWait() < 0)
+return -1;
+}
+return 0;
+}
+
+
+/**
  * virStateCleanup:
  *
  * Run each virtualization driver's cleanup method.
diff --git a/src/libvirt_internal.h b/src/libvirt_internal.h
index 72c6127..5b6035f 100644
--- a/src/libvirt_internal.h
+++ b/src/libvirt_internal.h
@@ -34,6 +34,8 @@ int virStateInitialize(bool privileged,
const char *root,
virStateInhibitCallback inhibit,
void *opaque);
+int virStateShutdown(void);
+int virStateShutdownWait(void);
 int virStateCleanup(void);
 int virStateReload(void);
 int virStateStop(void);
-- 
1.8.3.1