Re: [win-pv-devel] [PATCH] Add override for console log level

[Paul Durrant <Paul.Durrant@xxxxxxxxxx>]

> -----Original Message-----
> From: win-pv-devel [mailto:win-pv-devel-bounces@xxxxxxxxxxxxxxxxxxxx] On
> Behalf Of owen.smith@xxxxxxxxxx
> Sent: 13 July 2017 12:46
> To: win-pv-devel@xxxxxxxxxxxxxxxxxxxx
> Cc: Owen Smith <owen.smith@xxxxxxxxxx>
> Subject: [win-pv-devel] [PATCH] Add override for console log level
> 
> From: Owen Smith <owen.smith@xxxxxxxxxx>
> 
> Use the registry DWORD value called "ConsoleLogLevel" at
> "HKLM\System\CurrentControlSet\services\xenbus\Parameters" to
> override the default console logging output of:
> LOG_LEVEL_INFO | LOG_LEVEL_WARNING | LOG_LEVEL_ERROR |
> LOG_LEVEL_CRITICAL
> 
> Signed-off-by: Owen Smith <owen.smith@xxxxxxxxxx>
> ---
>  src/xenbus/driver.c | 39 +++++++++++++++++++++++++++++++++++++++
>  src/xenbus/driver.h |  5 +++++
>  src/xenbus/fdo.c    | 17 +++++++++--------
>  3 files changed, 53 insertions(+), 8 deletions(-)
> 
> diff --git a/src/xenbus/driver.c b/src/xenbus/driver.c
> index bbbda6c..270b60f 100644
> --- a/src/xenbus/driver.c
> +++ b/src/xenbus/driver.c
> @@ -48,6 +48,7 @@
>  typedef struct _XENBUS_DRIVER {
>      PDRIVER_OBJECT      DriverObject;
>      HANDLE              ParametersKey;
> +    ULONG               ConsoleLogLevel;
> 
>      MUTEX               Mutex;
>      LIST_ENTRY          List;
> @@ -122,6 +123,30 @@ DriverGetParametersKey(
>      return __DriverGetParametersKey();
>  }
> 
> +static FORCEINLINE VOID
> +__DriverSetConsoleLogLevel(
> +    IN  ULONG   LogLevel
> +    )
> +{
> +    Driver.ConsoleLogLevel = LogLevel;
> +}
> +
> +static FORCEINLINE ULONG
> +__DriverGetConsoleLogLevel(
> +    VOID
> +    )
> +{
> +    return Driver.ConsoleLogLevel;
> +}
> +
> +ULONG
> +DriverGetConsoleLogLevel(
> +    VOID
> +    )
> +{
> +    return __DriverGetConsoleLogLevel();
> +}
> +
>  #define MAXNAMELEN  128
> 
>  static FORCEINLINE VOID
> @@ -568,6 +593,8 @@ DriverUnload(
>      RtlZeroMemory(&Driver.List, sizeof (LIST_ENTRY));
>      RtlZeroMemory(&Driver.Mutex, sizeof (MUTEX));
> 
> +    __DriverSetConsoleLogLevel(0);
> +
>      ParametersKey = __DriverGetParametersKey();
> 
>      RegistryCloseKey(ParametersKey);
> @@ -680,6 +707,7 @@ DriverEntry(
>      HANDLE              ServiceKey;
>      HANDLE              ParametersKey;
>      ULONG               Index;
> +    ULONG               LogLevel;
>      NTSTATUS            status;
> 
>      ASSERT3P(__DriverGetDriverObject(), ==, NULL);
> @@ -721,6 +749,17 @@ DriverEntry(
> 
>      __DriverSetParametersKey(ParametersKey);
> 
> +    status = RegistryQueryDwordValue(ParametersKey,
> +                                     "ConsoleLogLevel",
> +                                     &LogLevel);
> +    if (!NT_SUCCESS(status))
> +        LogLevel = (ULONG)(LOG_LEVEL_INFO |
> +                           LOG_LEVEL_WARNING |
> +                           LOG_LEVEL_ERROR |
> +                           LOG_LEVEL_CRITICAL);
> +
> +    __DriverSetConsoleLogLevel(LogLevel);
> +

A DWORD is not the most friendly thing here. It means that someone has to look 
up values in a header file to know what to set. I think a multi-string of 
"info", "warning", "error" and/or "critical" would be better. The INF file 
could populate the default. It might also be useful to pull the parsing into 
xen logging code (rather than xenbus code) as it could then be re-used for 
registry keys to configure Xen and QEMU logging too.

  Paul

>      RegistryCloseKey(ServiceKey);
> 
>      status = XenTouch(__MODULE__,
> diff --git a/src/xenbus/driver.h b/src/xenbus/driver.h
> index dd81e4c..5f26c0d 100644
> --- a/src/xenbus/driver.h
> +++ b/src/xenbus/driver.h
> @@ -42,6 +42,11 @@ DriverGetParametersKey(
>      VOID
>      );
> 
> +extern ULONG
> +DriverGetConsoleLogLevel(
> +    VOID
> +    );
> +
>  extern VOID
>  DriverRequestReboot(
>      VOID
> diff --git a/src/xenbus/fdo.c b/src/xenbus/fdo.c
> index 0aeea3d..d44521b 100644
> --- a/src/xenbus/fdo.c
> +++ b/src/xenbus/fdo.c
> @@ -2656,6 +2656,7 @@ __FdoD3ToD0(
>      IN  PXENBUS_FDO Fdo
>      )
>  {
> +    ULONG           LogLevel;
>      NTSTATUS        status;
> 
>      Trace("====>\n");
> @@ -2680,14 +2681,14 @@ __FdoD3ToD0(
>                    Fdo->Channel,
>                    FALSE);
> 
> -    status = LogAddDisposition(LOG_LEVEL_INFO |
> -                               LOG_LEVEL_WARNING |
> -                               LOG_LEVEL_ERROR |
> -                               LOG_LEVEL_CRITICAL,
> -                               FdoOutputBuffer,
> -                               Fdo,
> -                               &Fdo->LogDisposition);
> -    ASSERT(NT_SUCCESS(status));
> +    LogLevel = DriverGetConsoleLogLevel();
> +    if (LogLevel != 0) {
> +        status = LogAddDisposition(LogLevel,
> +                                   FdoOutputBuffer,
> +                                   Fdo,
> +                                   &Fdo->LogDisposition);
> +        ASSERT(NT_SUCCESS(status));
> +    }
> 
>      status = XENBUS_STORE(WatchAdd,
>                            &Fdo->StoreInterface,
> --
> 2.8.3
> 
> 
> _______________________________________________
> win-pv-devel mailing list
> win-pv-devel@xxxxxxxxxxxxxxxxxxxx
> https://lists.xenproject.org/cgi-bin/mailman/listinfo/win-pv-devel
_______________________________________________
win-pv-devel mailing list
win-pv-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/cgi-bin/mailman/listinfo/win-pv-devel