On 11/07/16 01:47, Fan, Jeff wrote: > Laszlo, > > Yes. MP PPI and Protocol still be installed even there is only one processor > supported or found?
I'm sorry -- are you confirming that the PPI and the protocol will exist, or are you asking if I would like them to exist? (I'm confused by the question mark at the end of your second sentence.) Thanks! Laszlo > -----Original Message----- > From: edk2-devel [mailto:edk2-devel-boun...@lists.01.org] On Behalf Of Laszlo > Ersek > Sent: Saturday, November 05, 2016 12:40 AM > To: Fan, Jeff; edk2-de...@ml01.01.org > Cc: Kinney, Michael D; Tian, Feng; Gao, Liming > Subject: Re: [edk2] [PATCH] UefiCpuPkg/MpInitLib: Do not wakeup AP if only > one processor supported > > On 11/04/16 09:18, Jeff Fan wrote: >> If MaxLogicalProcessorNumber is only 1, we needn't to wake up APs at >> all and needn't to register callback functions. >> >> It could improve boot performance on single supported system. >> >> https://bugzilla.tianocore.org/show_bug.cgi?id=204 >> >> Cc: Feng Tian <feng.t...@intel.com> >> Cc: Liming Gao <liming....@intel.com> >> Cc: Michael Kinney <michael.d.kin...@intel.com> >> Contributed-under: TianoCore Contribution Agreement 1.0 >> Signed-off-by: Jeff Fan <jeff....@intel.com> >> --- >> UefiCpuPkg/Library/MpInitLib/DxeMpLib.c | 7 ++++++ >> UefiCpuPkg/Library/MpInitLib/MpLib.c | 39 >> +++++++++++++++++++-------------- >> UefiCpuPkg/Library/MpInitLib/PeiMpLib.c | 8 +++++++ >> 3 files changed, 37 insertions(+), 17 deletions(-) > > The MP services protocol and PPI that depend on this library will remain > available to callers, right? > > Thanks > Laszlo > >> diff --git a/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c >> b/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c >> index b399f1c..eb36d6f 100644 >> --- a/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c >> +++ b/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c >> @@ -290,6 +290,13 @@ InitMpGlobalData ( >> >> SaveCpuMpData (CpuMpData); >> >> + if (CpuMpData->CpuCount == 1) { >> + // >> + // If only BSP exists, return >> + // >> + return; >> + } >> + >> // >> // Avoid APs access invalid buff data which allocated by BootServices, >> // so we will allocate reserved data for AP loop code. >> diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.c >> b/UefiCpuPkg/Library/MpInitLib/MpLib.c >> index 56b870e..a0edc55 100644 >> --- a/UefiCpuPkg/Library/MpInitLib/MpLib.c >> +++ b/UefiCpuPkg/Library/MpInitLib/MpLib.c >> @@ -1143,6 +1143,7 @@ MpInitLibInitialize ( >> } else { >> MaxLogicalProcessorNumber = OldCpuMpData->CpuCount; >> } >> + ASSERT (MaxLogicalProcessorNumber != 0); >> >> AsmGetAddressMap (&AddressMap); >> ApResetVectorSize = AddressMap.RendezvousFunnelSize + sizeof >> (MP_CPU_EXCHANGE_INFO); @@ -1209,10 +1210,12 @@ MpInitLibInitialize ( >> MtrrGetAllMtrrs (&CpuMpData->MtrrTable); >> >> if (OldCpuMpData == NULL) { >> - // >> - // Wakeup all APs and calculate the processor count in system >> - // >> - CollectProcessorCount (CpuMpData); >> + if (MaxLogicalProcessorNumber > 1) { >> + // >> + // Wakeup all APs and calculate the processor count in system >> + // >> + CollectProcessorCount (CpuMpData); >> + } >> } else { >> // >> // APs have been wakeup before, just get the CPU Information @@ >> -1238,19 +1241,21 @@ MpInitLibInitialize ( >> sizeof (CPU_VOLATILE_REGISTERS) >> ); >> } >> - // >> - // Wakeup APs to do some AP initialize sync >> - // >> - WakeUpAP (CpuMpData, TRUE, 0, ApInitializeSync, CpuMpData); >> - // >> - // Wait for all APs finished initialization >> - // >> - while (CpuMpData->FinishedCount < (CpuMpData->CpuCount - 1)) { >> - CpuPause (); >> - } >> - CpuMpData->InitFlag = ApInitDone; >> - for (Index = 0; Index < CpuMpData->CpuCount; Index++) { >> - SetApState (&CpuMpData->CpuData[Index], CpuStateIdle); >> + if (MaxLogicalProcessorNumber > 1) { >> + // >> + // Wakeup APs to do some AP initialize sync >> + // >> + WakeUpAP (CpuMpData, TRUE, 0, ApInitializeSync, CpuMpData); >> + // >> + // Wait for all APs finished initialization >> + // >> + while (CpuMpData->FinishedCount < (CpuMpData->CpuCount - 1)) { >> + CpuPause (); >> + } >> + CpuMpData->InitFlag = ApInitDone; >> + for (Index = 0; Index < CpuMpData->CpuCount; Index++) { >> + SetApState (&CpuMpData->CpuData[Index], CpuStateIdle); >> + } >> } >> } >> >> diff --git a/UefiCpuPkg/Library/MpInitLib/PeiMpLib.c >> b/UefiCpuPkg/Library/MpInitLib/PeiMpLib.c >> index e242d37..1f2fcb8 100644 >> --- a/UefiCpuPkg/Library/MpInitLib/PeiMpLib.c >> +++ b/UefiCpuPkg/Library/MpInitLib/PeiMpLib.c >> @@ -321,6 +321,14 @@ InitMpGlobalData ( >> EFI_STATUS Status; >> >> SaveCpuMpData (CpuMpData); >> + >> + if (CpuMpData->CpuCount == 1) { >> + // >> + // If only BSP exists, return >> + // >> + return; >> + } >> + >> // >> // Register an event for EndOfPei >> // >> > > _______________________________________________ > edk2-devel mailing list > edk2-devel@lists.01.org > https://lists.01.org/mailman/listinfo/edk2-devel > _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
