RFC: Add BaseLib/QuickSort in MdePkg

Andrew Fish

On Sep 15, 2021, at 6:26 PM, gaoliming <gaoliming@...> wrote:

 SortLib has been added since 2015. I would suggest to still keep this library class. To resolve the package dependency, my proposal is to move the library class header file SortLib.h from MdeModulePkg to MdePkg, and still keep the library instance in MdeModulePkg. This proposal has no impact on the existing platform. 

If we add QuickSort() API to the BaseLib can we not just port the existing MdeModulePkg/SortLib to use QuickSort() in the implementation? Or is there some other way to add the new thing in a backward compatible way.


Andrew Fish

发件人: devel@edk2.groups.io <devel@edk2.groups.io> 代表 Ni, Ray
发送时间: 2021914 14:15
收件人: Kinney, Michael D <michael.d.kinney@...>; Gao, Liming <liming.gao@...>; Liu, Zhiguang <zhiguang.liu@...>; Wang, Jian J <jian.j.wang@...>; Gao, Zhichao <zhichao.gao@...>
抄送: devel@edk2.groups.io; Chan, Amy <amy.chan@...>
主题: [edk2-devel] RFC: Add BaseLib/QuickSort in MdePkg
Hi package maintainers of MdePkg, MdeModulePkg and ShellPkg, community,
A commit (UefiCpuPkg/CpuCacheInfoLib: Sort CpuCacheInfo array) to UefiCpuPkg let
UefiCpuPkg depend on MdeModulePkg because the SortLib class and instances are all in MdeModulePkg.
UefiCpuPkg depending on MdeModulePkg breaks the rule that “UefiCpuPkg should ONLY depend on MdePkg”.
To address this issue, there are two approaches:
  1. Duplicate the sort logic in UefiCpuPkg to not depend on MdeModulePkg/SortLib
  2. Add QuickSort() API to BaseLib in MdePkg.
Approach #2 (MdePkg/BaseLib/QuickSort) makes more sense because quick sort is a standard algorithm.
We encourage consumers to update their code to use the quick sort in MdePkg and gradually deprecate today’s MdeModulePkg/SortLib.
If you don’t have concerns, I plan to:
  1. “Add QuickSort() to BaseLib” and update all existing consumers to use this API instead.
QuickSort (
  IN OUT VOID                   *BufferToSort,
  IN CONST UINTN                Count,
  IN CONST UINTN                ElementSize,
  IN       SORT_COMPARE         CompareFunction
  1. “Add new ShellPkg/SortCompareLib”
Background: ShellPkg requires to sort devicepath/string so 3 APIs in UefiSortLib (DevicePathCompare, StringNoCaseCompare, StringCompare) are provided for Shell usage. we can move the 3 APIs to the SortCompareLib and update Shell code to use BaseLib/QuickSort directly, with the sort compare function from SortCompareLib.
Any concerns?