From c9b449213337172d629197a75390a151eba65eb6 Mon Sep 17 00:00:00 2001 From: Ruiyu Ni Date: Mon, 17 Apr 2017 11:20:47 +0800 Subject: [PATCH] UefiCpuPkg/MtrrLib: Avoid running unnecessary code Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ruiyu Ni Reviewed-by: Hao A Wu --- UefiCpuPkg/Library/MtrrLib/MtrrLib.c | 35 +++++++++++++++------------- 1 file changed, 19 insertions(+), 16 deletions(-) diff --git a/UefiCpuPkg/Library/MtrrLib/MtrrLib.c b/UefiCpuPkg/Library/MtrrLib/MtrrLib.c index c38191a7ef..9d1927262a 100644 --- a/UefiCpuPkg/Library/MtrrLib/MtrrLib.c +++ b/UefiCpuPkg/Library/MtrrLib/MtrrLib.c @@ -1536,6 +1536,7 @@ MtrrLibAddVariableMtrr ( MTRR_LIB_ASSERT_ALIGNED (BaseAddress, Length); if (Type == CacheInvalid) { + ASSERT (Ranges != NULL); for (Index = 0; Index < RangeCount; Index++) { if (Ranges[Index].BaseAddress <= BaseAddress && BaseAddress < Ranges[Index].BaseAddress + Ranges[Index].Length) { @@ -2027,25 +2028,27 @@ MtrrSetMemoryAttributeWorker ( ASSERT (OriginalVariableMtrrCount - FreeVariableMtrrCount <= FirmwareVariableMtrrCount); // - // Move MTRRs after the FirmwraeVariableMtrrCount position to beginning + // Move MTRRs after the FirmwareVariableMtrrCount position to beginning // - WorkingIndex = FirmwareVariableMtrrCount; - for (Index = 0; Index < FirmwareVariableMtrrCount; Index++) { - if (!OriginalVariableMtrr[Index].Valid) { - // - // Found an empty MTRR in WorkingIndex position - // - for (; WorkingIndex < OriginalVariableMtrrCount; WorkingIndex++) { - if (OriginalVariableMtrr[WorkingIndex].Valid) { - break; + if (FirmwareVariableMtrrCount < OriginalVariableMtrrCount) { + WorkingIndex = FirmwareVariableMtrrCount; + for (Index = 0; Index < FirmwareVariableMtrrCount; Index++) { + if (!OriginalVariableMtrr[Index].Valid) { + // + // Found an empty MTRR in WorkingIndex position + // + for (; WorkingIndex < OriginalVariableMtrrCount; WorkingIndex++) { + if (OriginalVariableMtrr[WorkingIndex].Valid) { + break; + } } - } - if (WorkingIndex != OriginalVariableMtrrCount) { - CopyMem (&OriginalVariableMtrr[Index], &OriginalVariableMtrr[WorkingIndex], sizeof (VARIABLE_MTRR)); - VariableSettingModified[Index] = TRUE; - VariableSettingModified[WorkingIndex] = TRUE; - OriginalVariableMtrr[WorkingIndex].Valid = FALSE; + if (WorkingIndex != OriginalVariableMtrrCount) { + CopyMem (&OriginalVariableMtrr[Index], &OriginalVariableMtrr[WorkingIndex], sizeof (VARIABLE_MTRR)); + VariableSettingModified[Index] = TRUE; + VariableSettingModified[WorkingIndex] = TRUE; + OriginalVariableMtrr[WorkingIndex].Valid = FALSE; + } } } } -- 2.39.2