BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3902
Bad IO performance in SEC phase is observed after TDX features was introduced. (after commit b6b2de884864 - "MdePkg: Support mmio for Tdx guest in BaseIoLibIntrinsic"). This is because IsTdxGuest() will be called in each MMIO operation. It is trying to cache the result of the probe in the efi data segment. However, that doesn't work in SEC, because the data segment is read only (so the write seems to succeed but a read will always return the original value), leading to us calling TdIsEnabled() check for every mmio we do, which is causing the slowdown because it's very expensive. TdProbe is introduced in this patch-set. It is called in BaseIoLibIntrinsicSev instead of IsTdxGuest. There are 2 versions of the TdProbeLib. Null instance of TdProbe always returns TD_PROBE_NON. Its OvmfPkg version checks the Ovmf work area to determine the Td guest type. Cc: Michael D Kinney <michael.d.kin...@intel.com> Cc: Liming Gao <gaolim...@byosoft.com.cn> Cc: Zhiguang Liu <zhiguang....@intel.com> Cc: James Bottomley <j...@linux.ibm.com> Cc: James Bottomley <james.bottom...@hansenpartnership.com> Cc: Jiewen Yao <jiewen....@intel.com> Cc: Gerd Hoffmann <kra...@redhat.com> Cc: Brijesh Singh <brijesh.si...@amd.com> Cc: Erdem Aktas <erdemak...@google.com> Cc: Tom Lendacky <thomas.lenda...@amd.com> Signed-off-by: Min Xu <min.m...@intel.com> Min Xu (4): MdePkg: Add TdProbeLib OvmfPkg/IntelTdx: Add TdProbeLib MdePkg: Probe Td guest in BaseIoLibIntrinsicSev OvmfPkg: Add TdProbeLib in *.dsc MdePkg/Include/Library/TdProbeLib.h | 26 +++++++++++++ .../BaseIoLibIntrinsicSev.inf | 1 + .../BaseIoLibIntrinsic/IoLibInternalTdx.c | 13 +------ .../Library/TdProbeLibNull/TdProbeLibNull.c | 25 ++++++++++++ .../Library/TdProbeLibNull/TdProbeLibNull.inf | 21 ++++++++++ MdePkg/MdePkg.dec | 5 +++ MdePkg/MdePkg.dsc | 1 + OvmfPkg/AmdSev/AmdSevX64.dsc | 1 + OvmfPkg/Bhyve/BhyveX64.dsc | 1 + OvmfPkg/CloudHv/CloudHvX64.dsc | 1 + OvmfPkg/IntelTdx/IntelTdxX64.dsc | 1 + OvmfPkg/IntelTdx/TdProbeLib/TdProbeLib.c | 38 +++++++++++++++++++ OvmfPkg/IntelTdx/TdProbeLib/TdProbeLib.inf | 25 ++++++++++++ OvmfPkg/Microvm/MicrovmX64.dsc | 1 + OvmfPkg/OvmfPkgIa32.dsc | 1 + OvmfPkg/OvmfPkgIa32X64.dsc | 1 + OvmfPkg/OvmfPkgX64.dsc | 1 + OvmfPkg/OvmfXen.dsc | 1 + 18 files changed, 153 insertions(+), 11 deletions(-) create mode 100644 MdePkg/Include/Library/TdProbeLib.h create mode 100644 MdePkg/Library/TdProbeLibNull/TdProbeLibNull.c create mode 100644 MdePkg/Library/TdProbeLibNull/TdProbeLibNull.inf create mode 100644 OvmfPkg/IntelTdx/TdProbeLib/TdProbeLib.c create mode 100644 OvmfPkg/IntelTdx/TdProbeLib/TdProbeLib.inf -- 2.29.2.windows.2 -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#88861): https://edk2.groups.io/g/devel/message/88861 Mute This Topic: https://groups.io/mt/90436749/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
