On 11/08/16 01:55, Fan, Jeff wrote: > Laszlo, > > Oh. Sorry for the question mark in my last sentence and confusing you. :-) it > should be point. It's my typo. > > MP PPI and the protocol DO exist even there is only one processor in the > system. > > Thanks! > Jeff
Thanks. With that guarantee, the proposed change looks sensible. I didn't review the patch, but I want to confirm that (with the above guarantee) I agree with its goal: Acked-by: Laszlo Ersek <ler...@redhat.com> Thanks Laszlo > -----Original Message----- > From: edk2-devel [mailto:edk2-devel-boun...@lists.01.org] On Behalf Of Laszlo > Ersek > Sent: Monday, November 07, 2016 9:37 PM > 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 11/07/16 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 > _______________________________________________ > 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
