Ray: 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. Thanks Liming 发件人: devel@edk2.groups.io 代表 Ni, Ray 发送时间: 2021年9月14日 14:15 收件人: Kinney, Michael D ; Gao, Liming ; Liu, Zhiguang ; Wang, Jian J ; Gao, Zhichao 抄送: devel@edk2.groups.io; Chan, Amy 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. VOID EFIAPI QuickSort ( IN OUT VOID *BufferToSort, IN CONST UINTN Count, IN CONST UINTN ElementSize, IN SORT_COMPARE CompareFunction ); 2. “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? Thanks, Ray