Re: [PATCH v3 3/5] UefiCpuPkg/SmmCpuFeaturesLib: Cleanup library constructors

["Laszlo Ersek" <lersek@redhat.com>]

On 02/17/21 22:32, mikuback@linux.microsoft.com wrote:
> From: Michael Kubacki <michael.kubacki@microsoft.com>
> 
> There's currently two library instances:
>   1. SmmCpuFeaturesLib
>   2. SmmCpuFeaturesLibStm
> 
> There's two constructor functions:
>   1. SmmCpuFeaturesLibConstructor()
>   2. SmmCpuFeaturesLibStmConstructor()
> 
> SmmCpuFeaturesLibConstructor() is called by
> SmmCpuFeaturesLibStmConstructor() since the functionality in that
> function is required by both library instances.
> 
> The declaration for SmmCpuFeaturesLibConstructor() is embedded in
> "SmmStm.c" instead of being declared in a header file. Further,
> that constructor function is called by the STM specific constructor.
> 
> This change moves the common code to a function called
> CpuFeaturesLibInitialization() which is declared in an internal
> library header file "CpuFeaturesLib.h". Each constructor simply
> calls this function to perform the common functionality.
> 
> Additionally, SmmCpuFeaturesLibConstructor() is moved from
> SmmCpuFeaturesLibNoStm.c into a instance-specific file allowing
> SmmCpuFeaturesLibNoStm.c to contain no STM implementation agnostic
> to a particular library instance.
> 
> Cc: Eric Dong <eric.dong@intel.com>
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Cc: Rahul Kumar <rahul1.kumar@intel.com>
> Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
> Reviewed-by: Laszlo Ersek <lersek@redhat.com>
> ---
>  UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.c       | 31 ++++++++++++++++++++
>  UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLibCommon.c | 19 +++++-------
>  UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmStm.c                  | 23 ++-------------
>  UefiCpuPkg/Library/SmmCpuFeaturesLib/CpuFeaturesLib.h          | 12 ++++++++
>  UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.inf     |  1 +
>  5 files changed, 54 insertions(+), 32 deletions(-)

The update looks OK, thanks.
Laszlo

> 
> diff --git a/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.c b/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.c
> new file mode 100644
> index 000000000000..00948a191fad
> --- /dev/null
> +++ b/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.c
> @@ -0,0 +1,31 @@
> +/** @file
> +Implementation specific to the SmmCpuFeatureLib library instance.
> +
> +Copyright (c) Microsoft Corporation.<BR>
> +SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#include <PiSmm.h>
> +#include "CpuFeaturesLib.h"
> +
> +/**
> +  The constructor function for the Traditional MM library instance without STM.
> +
> +  @param[in]  ImageHandle  The firmware allocated handle for the EFI image.
> +  @param[in]  SystemTable  A pointer to the EFI System Table.
> +
> +  @retval EFI_SUCCESS      The constructor always returns EFI_SUCCESS.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +SmmCpuFeaturesLibConstructor (
> +  IN EFI_HANDLE        ImageHandle,
> +  IN EFI_SYSTEM_TABLE  *SystemTable
> +  )
> +{
> +  CpuFeaturesLibInitialization ();
> +
> +  return EFI_SUCCESS;
> +}
> diff --git a/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLibCommon.c b/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLibCommon.c
> index 36c48310c31e..7a919c5ee70f 100644
> --- a/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLibCommon.c
> +++ b/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLibCommon.c
> @@ -2,6 +2,7 @@
>  Implementation shared across all library instances.
>  
>  Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) Microsoft Corporation.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
>  
>  **/
> @@ -63,19 +64,15 @@ BOOLEAN  mNeedConfigureMtrrs = TRUE;
>  BOOLEAN  *mSmrrEnabled;
>  
>  /**
> -  The constructor function
> +  Performs library initialization.
>  
> -  @param[in]  ImageHandle  The firmware allocated handle for the EFI image.
> -  @param[in]  SystemTable  A pointer to the EFI System Table.
> -
> -  @retval EFI_SUCCESS      The constructor always returns EFI_SUCCESS.
> +  This initialization function contains common functionality shared betwen all
> +  library instance constructors.
>  
>  **/
> -EFI_STATUS
> -EFIAPI
> -SmmCpuFeaturesLibConstructor (
> -  IN EFI_HANDLE        ImageHandle,
> -  IN EFI_SYSTEM_TABLE  *SystemTable
> +VOID
> +CpuFeaturesLibInitialization (
> +  VOID
>    )
>  {
>    UINT32  RegEax;
> @@ -162,8 +159,6 @@ SmmCpuFeaturesLibConstructor (
>    //
>    mSmrrEnabled = (BOOLEAN *)AllocatePool (sizeof (BOOLEAN) * PcdGet32 (PcdCpuMaxLogicalProcessorNumber));
>    ASSERT (mSmrrEnabled != NULL);
> -
> -  return EFI_SUCCESS;
>  }
>  
>  /**
> diff --git a/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmStm.c b/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmStm.c
> index b5aad41fdb64..dcc2e9f9a09a 100644
> --- a/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmStm.c
> +++ b/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmStm.c
> @@ -30,22 +30,6 @@
>  #define RDWR_ACCS             3
>  #define FULL_ACCS             7
>  
> -/**
> -  The constructor function
> -
> -  @param[in]  ImageHandle  The firmware allocated handle for the EFI image.
> -  @param[in]  SystemTable  A pointer to the EFI System Table.
> -
> -  @retval EFI_SUCCESS      The constructor always returns EFI_SUCCESS.
> -
> -**/
> -EFI_STATUS
> -EFIAPI
> -SmmCpuFeaturesLibConstructor (
> -  IN EFI_HANDLE        ImageHandle,
> -  IN EFI_SYSTEM_TABLE  *SystemTable
> -  );
> -
>  EFI_HANDLE  mStmSmmCpuHandle = NULL;
>  
>  BOOLEAN mLockLoadMonitor = FALSE;
> @@ -112,7 +96,7 @@ UINTN  mMsegSize = 0;
>  BOOLEAN  mStmConfigurationTableInitialized = FALSE;
>  
>  /**
> -  The constructor function
> +  The constructor function for the Traditional MM library instance with STM.
>  
>    @param[in]  ImageHandle  The firmware allocated handle for the EFI image.
>    @param[in]  SystemTable  A pointer to the EFI System Table.
> @@ -138,10 +122,9 @@ SmmCpuFeaturesLibStmConstructor (
>    SmmCpuFeaturesLibStmSmiEntryFixupAddress ();
>  
>    //
> -  // Call the common constructor function
> +  // Perform library initialization common across all instances
>    //
> -  Status = SmmCpuFeaturesLibConstructor (ImageHandle, SystemTable);
> -  ASSERT_EFI_ERROR (Status);
> +  CpuFeaturesLibInitialization ();
>  
>    //
>    // Lookup the MP Services Protocol
> diff --git a/UefiCpuPkg/Library/SmmCpuFeaturesLib/CpuFeaturesLib.h b/UefiCpuPkg/Library/SmmCpuFeaturesLib/CpuFeaturesLib.h
> index 4645bbb066c9..f9a758e82558 100644
> --- a/UefiCpuPkg/Library/SmmCpuFeaturesLib/CpuFeaturesLib.h
> +++ b/UefiCpuPkg/Library/SmmCpuFeaturesLib/CpuFeaturesLib.h
> @@ -9,6 +9,18 @@
>  #ifndef _CPU_FEATURES_LIB_H_
>  #define _CPU_FEATURES_LIB_H_
>  
> +/**
> +  Performs library initialization.
> +
> +  This initialization function contains common functionality shared betwen all
> +  library instance constructors.
> +
> +**/
> +VOID
> +CpuFeaturesLibInitialization (
> +  VOID
> +  );
> +
>  /**
>    Internal worker function that is called to complete CPU initialization at the
>    end of SmmCpuFeaturesInitializeProcessor().
> diff --git a/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.inf b/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.inf
> index 7ebb0b0ef011..ddd00eeceb84 100644
> --- a/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.inf
> +++ b/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.inf
> @@ -18,6 +18,7 @@ [Defines]
>  
>  [Sources]
>    CpuFeaturesLib.h
> +  SmmCpuFeaturesLib.c
>    SmmCpuFeaturesLibCommon.c
>    SmmCpuFeaturesLibNoStm.c
>  
>