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| author | Tom Lendacky <thomas.lendacky@amd.com> | 2020-09-23 13:04:00 -0500 |
|---|---|---|
| committer | mergify[bot] <37929162+mergify[bot]@users.noreply.github.com> | 2020-10-19 21:47:21 +0000 |
| commit | 93edd1887e34c3959ce927da1a22e8c54ce18a83 (patch) | |
| tree | 8794258244cbafa7e95c6b66726e5a17c8344dc6 /UefiCpuPkg | |
| parent | 92e9c44f205a876556abe1a1addea5c40e4f3ccf (diff) | |
| download | edk2-93edd1887e34c3959ce927da1a22e8c54ce18a83.tar.gz edk2-93edd1887e34c3959ce927da1a22e8c54ce18a83.tar.bz2 edk2-93edd1887e34c3959ce927da1a22e8c54ce18a83.zip | |
UefiCpuPkg/MpInitLib: Reduce reset vector memory pressure
The AP reset vector stack allocation is only required if running as an
SEV-ES guest. Since the reset vector allocation is below 1MB in memory,
eliminate the requirement for bare-metal systems and non SEV-ES guests
to allocate the extra stack area, which can be large if the
PcdCpuMaxLogicalProcessorNumber value is large, and also remove the
CPU_STACK_ALIGNMENT alignment.
Fixes: 7b7508ad784d ("UefiCpuPkg: Allow AP booting under SEV-ES")
Cc: Garrett Kirkendall <garrett.kirkendall@amd.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <21345cdbc906519558202b3851257ca07b9239ba.1600884239.git.thomas.lendacky@amd.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
[lersek@redhat.com: supply missing space character after "PcdGet32"]
Diffstat (limited to 'UefiCpuPkg')
| -rw-r--r-- | UefiCpuPkg/Library/MpInitLib/MpLib.c | 36 |
1 files changed, 17 insertions, 19 deletions
diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.c b/UefiCpuPkg/Library/MpInitLib/MpLib.c index 07426274f6..6d977d45bc 100644 --- a/UefiCpuPkg/Library/MpInitLib/MpLib.c +++ b/UefiCpuPkg/Library/MpInitLib/MpLib.c @@ -1142,20 +1142,6 @@ RestoreWakeupBuffer( }
/**
- Calculate the size of the reset stack.
-
- @return Total amount of memory required for stacks
-**/
-STATIC
-UINTN
-GetApResetStackSize (
- VOID
- )
-{
- return AP_RESET_STACK_SIZE * PcdGet32(PcdCpuMaxLogicalProcessorNumber);
-}
-
-/**
Calculate the size of the reset vector.
@param[in] AddressMap The pointer to Address Map structure.
@@ -1170,11 +1156,23 @@ GetApResetVectorSize ( {
UINTN Size;
- Size = ALIGN_VALUE (AddressMap->RendezvousFunnelSize +
- AddressMap->SwitchToRealSize +
- sizeof (MP_CPU_EXCHANGE_INFO),
- CPU_STACK_ALIGNMENT);
- Size += GetApResetStackSize ();
+ Size = AddressMap->RendezvousFunnelSize +
+ AddressMap->SwitchToRealSize +
+ sizeof (MP_CPU_EXCHANGE_INFO);
+
+ //
+ // The AP reset stack is only used by SEV-ES guests. Do not add to the
+ // allocation if SEV-ES is not enabled.
+ //
+ if (PcdGetBool (PcdSevEsIsEnabled)) {
+ //
+ // Stack location is based on APIC ID, so use the total number of
+ // processors for calculating the total stack area.
+ //
+ Size += AP_RESET_STACK_SIZE * PcdGet32 (PcdCpuMaxLogicalProcessorNumber);
+
+ Size = ALIGN_VALUE (Size, CPU_STACK_ALIGNMENT);
+ }
return Size;
}
|