Define CPU_HOT_EJECT_DATA and add PCD PcdCpuHotEjectDataAddress, which
will be used to share CPU ejection state between OvmfPkg/CpuHotPlugSmm
and PiSmmCpuDxeSmm.
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Aaron Young <aaron.young@oracle.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3132
Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com>
---
Notes:
Addresses the following review comments in v6:
(1) Dropped modifications to LibraryClasses in OvmfPkg.dec
(2,3) Cleanup comments around PCD PcdCpuHotEjectDataAddress.
(4) Move PCD PcdCpuHotEjectDataAddress declaration in CpuHotplugSmm.inf
to a patch-7 where it actually gets used.
(5a,5b) Change the comment in the top block to use Laszlo's language.
Also detail when the PCD would contain a valid value.
(6) Move Library/CpuHotEjectData.h to Pcd/CpuHotEjectData.h
(7,15,16) Fixup guard macro to be C namespace compliant. Also fixup the
comment style near the endif guard.
(8-10) Rename CPU_HOT_EJECT_FN to a more EDK2 compliant style. Also add
a comment block and fix spacing.
() Rename ApicIdMap -> QemuSelectorMap while keeping the type as UINT64.
Related to a comment in patch-8 ("... add worker to do CPU ejection".)
(11a,11b) Rename CPU_EJECT_INVALID to CPU_EJECT_QEMU_SELECTOR_INVALID
and add a comment about it.
() Remove CPU_EJECT_WORKER based on review comment on a patch 8.
(12,14) Remove CPU_HOT_EJECT_DATA fields Revision and Reserved.
Reorder CPU_HOT_EJECT_DATA to minimize internal padding
and ensure elements are properly aligned.
(13a,13b) Change CpuIndex->ApicId map to ProcessorNum -> QemuSelector
() Make CPU_HOT_EJECT_HANDLER->Handler,
CPU_HOT_EJECT_HANDLER->QemuSelectorMap volatile.
OvmfPkg/OvmfPkg.dec | 4 +++
OvmfPkg/Include/Pcd/CpuHotEjectData.h | 52 +++++++++++++++++++++++++++++++++++
2 files changed, 56 insertions(+)
create mode 100644 OvmfPkg/Include/Pcd/CpuHotEjectData.h
diff --git a/OvmfPkg/OvmfPkg.dec b/OvmfPkg/OvmfPkg.dec
index 4348bb45c64a..9629707020ba 100644
--- a/OvmfPkg/OvmfPkg.dec
+++ b/OvmfPkg/OvmfPkg.dec
@@ -352,6 +352,10 @@ [PcdsDynamic, PcdsDynamicEx]
# This PCD is only accessed if PcdSmmSmramRequire is TRUE (see below).
gUefiOvmfPkgTokenSpaceGuid.PcdQ35SmramAtDefaultSmbase|FALSE|BOOLEAN|0x34
+ ## This PCD adds a communication channel between OVMF's SmmCpuFeaturesLib
+ # instance in PiSmmCpuDxeSmm, and CpuHotplugSmm.
+ gUefiOvmfPkgTokenSpaceGuid.PcdCpuHotEjectDataAddress|0|UINT64|0x46
+
[PcdsFeatureFlag]
gUefiOvmfPkgTokenSpaceGuid.PcdQemuBootOrderPciTranslation|TRUE|BOOLEAN|0x1c
gUefiOvmfPkgTokenSpaceGuid.PcdQemuBootOrderMmioTranslation|FALSE|BOOLEAN|0x1d
diff --git a/OvmfPkg/Include/Pcd/CpuHotEjectData.h b/OvmfPkg/Include/Pcd/CpuHotEjectData.h
new file mode 100644
index 000000000000..024a92726869
--- /dev/null
+++ b/OvmfPkg/Include/Pcd/CpuHotEjectData.h
@@ -0,0 +1,52 @@
+/** @file
+ Definition for the CPU_HOT_EJECT_DATA structure, which shares
+ CPU hot-eject state between OVMF's SmmCpuFeaturesLib instance in
+ PiSmmCpuDxeSmm, and CpuHotplugSmm.
+
+ CPU_HOT_EJECT_DATA is allocated in SMRAM, and pointed-to by
+ PcdCpuHotEjectDataAddress.
+
+ PcdCpuHotEjectDataAddress is valid when SMM_REQUIRE is TRUE
+ and MaxNumberOfCpus > 1.
+
+ Copyright (C) 2021, Oracle Corporation.
+
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#ifndef CPU_HOT_EJECT_DATA_H_
+#define CPU_HOT_EJECT_DATA_H_
+
+/**
+ CPU Hot-eject handler, called from SmmCpuFeaturesRendezvousExit()
+ on each CPU at exit from SMM.
+
+ @param[in] ProcessorNum ProcessorNum denotes the CPU exiting SMM,
+ and will be used as an index into
+ CPU_HOT_EJECT_DATA->QemuSelectorMap. It is
+ identical to the processor handle in
+ EFI_SMM_CPU_SERVICE_PROTOCOL.
+**/
+typedef
+VOID
+(EFIAPI *CPU_HOT_EJECT_HANDLER) (
+ IN UINTN ProcessorNum
+ );
+
+//
+// CPU_EJECT_QEMU_SELECTOR_INVALID marks CPUs not being ejected in
+// CPU_HOT_EJECT_DATA->QemuSelectorMap.
+//
+// QEMU CPU Selector is UINT32, so we choose an invalid value larger
+// than that type.
+//
+#define CPU_EJECT_QEMU_SELECTOR_INVALID (MAX_UINT64)
+
+typedef struct {
+ volatile UINT64 *QemuSelectorMap; // Maps ProcessorNum -> QemuSelector
+ // for pending hot-ejects
+ volatile CPU_HOT_EJECT_HANDLER Handler; // Handler to do the CPU ejection
+ UINT32 ArrayLength; // Entries in the QemuSelectorMap
+} CPU_HOT_EJECT_DATA;
+
+#endif // CPU_HOT_EJECT_DATA_H_
--
2.9.3
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On 02/22/21 08:19, Ankur Arora wrote:
> Define CPU_HOT_EJECT_DATA and add PCD PcdCpuHotEjectDataAddress, which
> will be used to share CPU ejection state between OvmfPkg/CpuHotPlugSmm
> and PiSmmCpuDxeSmm.
>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Cc: Jordan Justen <jordan.l.justen@intel.com>
> Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
> Cc: Igor Mammedov <imammedo@redhat.com>
> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
> Cc: Aaron Young <aaron.young@oracle.com>
> Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3132
> Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com>
> ---
>
> Notes:
> Addresses the following review comments in v6:
> (1) Dropped modifications to LibraryClasses in OvmfPkg.dec
> (2,3) Cleanup comments around PCD PcdCpuHotEjectDataAddress.
> (4) Move PCD PcdCpuHotEjectDataAddress declaration in CpuHotplugSmm.inf
> to a patch-7 where it actually gets used.
> (5a,5b) Change the comment in the top block to use Laszlo's language.
> Also detail when the PCD would contain a valid value.
> (6) Move Library/CpuHotEjectData.h to Pcd/CpuHotEjectData.h
> (7,15,16) Fixup guard macro to be C namespace compliant. Also fixup the
> comment style near the endif guard.
> (8-10) Rename CPU_HOT_EJECT_FN to a more EDK2 compliant style. Also add
> a comment block and fix spacing.
> () Rename ApicIdMap -> QemuSelectorMap while keeping the type as UINT64.
> Related to a comment in patch-8 ("... add worker to do CPU ejection".)
> (11a,11b) Rename CPU_EJECT_INVALID to CPU_EJECT_QEMU_SELECTOR_INVALID
> and add a comment about it.
> () Remove CPU_EJECT_WORKER based on review comment on a patch 8.
> (12,14) Remove CPU_HOT_EJECT_DATA fields Revision and Reserved.
> Reorder CPU_HOT_EJECT_DATA to minimize internal padding
> and ensure elements are properly aligned.
> (13a,13b) Change CpuIndex->ApicId map to ProcessorNum -> QemuSelector
> () Make CPU_HOT_EJECT_HANDLER->Handler,
> CPU_HOT_EJECT_HANDLER->QemuSelectorMap volatile.
>
> OvmfPkg/OvmfPkg.dec | 4 +++
> OvmfPkg/Include/Pcd/CpuHotEjectData.h | 52 +++++++++++++++++++++++++++++++++++
> 2 files changed, 56 insertions(+)
> create mode 100644 OvmfPkg/Include/Pcd/CpuHotEjectData.h
Very nice updates; I only have superficial comments this time:
(1) The patch -- correctly -- no longer touches CpuHotplugSmm, so please
remove "/CpuHotplugSmm" from the subject line.
>
> diff --git a/OvmfPkg/OvmfPkg.dec b/OvmfPkg/OvmfPkg.dec
> index 4348bb45c64a..9629707020ba 100644
> --- a/OvmfPkg/OvmfPkg.dec
> +++ b/OvmfPkg/OvmfPkg.dec
> @@ -352,6 +352,10 @@ [PcdsDynamic, PcdsDynamicEx]
> # This PCD is only accessed if PcdSmmSmramRequire is TRUE (see below).
> gUefiOvmfPkgTokenSpaceGuid.PcdQ35SmramAtDefaultSmbase|FALSE|BOOLEAN|0x34
>
> + ## This PCD adds a communication channel between OVMF's SmmCpuFeaturesLib
> + # instance in PiSmmCpuDxeSmm, and CpuHotplugSmm.
> + gUefiOvmfPkgTokenSpaceGuid.PcdCpuHotEjectDataAddress|0|UINT64|0x46
> +
> [PcdsFeatureFlag]
> gUefiOvmfPkgTokenSpaceGuid.PcdQemuBootOrderPciTranslation|TRUE|BOOLEAN|0x1c
> gUefiOvmfPkgTokenSpaceGuid.PcdQemuBootOrderMmioTranslation|FALSE|BOOLEAN|0x1d
> diff --git a/OvmfPkg/Include/Pcd/CpuHotEjectData.h b/OvmfPkg/Include/Pcd/CpuHotEjectData.h
> new file mode 100644
> index 000000000000..024a92726869
> --- /dev/null
> +++ b/OvmfPkg/Include/Pcd/CpuHotEjectData.h
> @@ -0,0 +1,52 @@
> +/** @file
> + Definition for the CPU_HOT_EJECT_DATA structure, which shares
> + CPU hot-eject state between OVMF's SmmCpuFeaturesLib instance in
> + PiSmmCpuDxeSmm, and CpuHotplugSmm.
> +
> + CPU_HOT_EJECT_DATA is allocated in SMRAM, and pointed-to by
> + PcdCpuHotEjectDataAddress.
> +
> + PcdCpuHotEjectDataAddress is valid when SMM_REQUIRE is TRUE
> + and MaxNumberOfCpus > 1.
(2) Looks good, thanks; please clarify it as follows though:
s/MaxNumberOfCpus/PcdCpuMaxLogicalProcessorNumber/
> +
> + Copyright (C) 2021, Oracle Corporation.
> +
> + SPDX-License-Identifier: BSD-2-Clause-Patent
> +**/
> +
> +#ifndef CPU_HOT_EJECT_DATA_H_
> +#define CPU_HOT_EJECT_DATA_H_
> +
> +/**
> + CPU Hot-eject handler, called from SmmCpuFeaturesRendezvousExit()
> + on each CPU at exit from SMM.
> +
> + @param[in] ProcessorNum ProcessorNum denotes the CPU exiting SMM,
> + and will be used as an index into
> + CPU_HOT_EJECT_DATA->QemuSelectorMap. It is
> + identical to the processor handle in
> + EFI_SMM_CPU_SERVICE_PROTOCOL.
> +**/
> +typedef
> +VOID
> +(EFIAPI *CPU_HOT_EJECT_HANDLER) (
> + IN UINTN ProcessorNum
> + );
> +
> +//
> +// CPU_EJECT_QEMU_SELECTOR_INVALID marks CPUs not being ejected in
> +// CPU_HOT_EJECT_DATA->QemuSelectorMap.
> +//
> +// QEMU CPU Selector is UINT32, so we choose an invalid value larger
> +// than that type.
> +//
> +#define CPU_EJECT_QEMU_SELECTOR_INVALID (MAX_UINT64)
> +
> +typedef struct {
> + volatile UINT64 *QemuSelectorMap; // Maps ProcessorNum -> QemuSelector
> + // for pending hot-ejects
> + volatile CPU_HOT_EJECT_HANDLER Handler; // Handler to do the CPU ejection
> + UINT32 ArrayLength; // Entries in the QemuSelectorMap
(3) Please move "*QemuSelectorMap" and "ArrayLength" to the right, by 9
spaces, so that they line up with "Handler".
Now... I realize that such an update would result in the awkwarly wide
code snippet:
> typedef struct {
> volatile UINT64 *QemuSelectorMap; // Maps ProcessorNum -> QemuSelector
> // for pending hot-ejects
> volatile CPU_HOT_EJECT_HANDLER Handler; // Handler to do the CPU ejection
> UINT32 ArrayLength; // Entries in the QemuSelectorMap
> };
where it is not really possible to re-wrap the comments usefully. With
that in mind, the following is likely the best approach:
> typedef struct {
> //
> // Maps ProcessorNum -> QemuSelector for pending hot-ejects
> //
> volatile UINT64 *QemuSelectorMap;
> //
> // Handler to do the CPU ejection
> //
> volatile CPU_HOT_EJECT_HANDLER Handler;
> //
> // Entries in the QemuSelectorMap
> //
> UINT32 ArrayLength;
> };
This way, you have ample room for the comments. Plus, the field names
need not care about any visual alignment, because they are separated by
the comments anyway.
Thanks!
Laszlo
> +} CPU_HOT_EJECT_DATA;
> +
> +#endif // CPU_HOT_EJECT_DATA_H_
>
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On 2021-02-22 5:06 a.m., Laszlo Ersek wrote:
> On 02/22/21 08:19, Ankur Arora wrote:
>> Define CPU_HOT_EJECT_DATA and add PCD PcdCpuHotEjectDataAddress, which
>> will be used to share CPU ejection state between OvmfPkg/CpuHotPlugSmm
>> and PiSmmCpuDxeSmm.
>>
>> Cc: Laszlo Ersek <lersek@redhat.com>
>> Cc: Jordan Justen <jordan.l.justen@intel.com>
>> Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
>> Cc: Igor Mammedov <imammedo@redhat.com>
>> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
>> Cc: Aaron Young <aaron.young@oracle.com>
>> Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3132
>> Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com>
>> ---
>>
>> Notes:
>> Addresses the following review comments in v6:
>> (1) Dropped modifications to LibraryClasses in OvmfPkg.dec
>> (2,3) Cleanup comments around PCD PcdCpuHotEjectDataAddress.
>> (4) Move PCD PcdCpuHotEjectDataAddress declaration in CpuHotplugSmm.inf
>> to a patch-7 where it actually gets used.
>> (5a,5b) Change the comment in the top block to use Laszlo's language.
>> Also detail when the PCD would contain a valid value.
>> (6) Move Library/CpuHotEjectData.h to Pcd/CpuHotEjectData.h
>> (7,15,16) Fixup guard macro to be C namespace compliant. Also fixup the
>> comment style near the endif guard.
>> (8-10) Rename CPU_HOT_EJECT_FN to a more EDK2 compliant style. Also add
>> a comment block and fix spacing.
>> () Rename ApicIdMap -> QemuSelectorMap while keeping the type as UINT64.
>> Related to a comment in patch-8 ("... add worker to do CPU ejection".)
>> (11a,11b) Rename CPU_EJECT_INVALID to CPU_EJECT_QEMU_SELECTOR_INVALID
>> and add a comment about it.
>> () Remove CPU_EJECT_WORKER based on review comment on a patch 8.
>> (12,14) Remove CPU_HOT_EJECT_DATA fields Revision and Reserved.
>> Reorder CPU_HOT_EJECT_DATA to minimize internal padding
>> and ensure elements are properly aligned.
>> (13a,13b) Change CpuIndex->ApicId map to ProcessorNum -> QemuSelector
>> () Make CPU_HOT_EJECT_HANDLER->Handler,
>> CPU_HOT_EJECT_HANDLER->QemuSelectorMap volatile.
>>
>> OvmfPkg/OvmfPkg.dec | 4 +++
>> OvmfPkg/Include/Pcd/CpuHotEjectData.h | 52 +++++++++++++++++++++++++++++++++++
>> 2 files changed, 56 insertions(+)
>> create mode 100644 OvmfPkg/Include/Pcd/CpuHotEjectData.h
>
> Very nice updates; I only have superficial comments this time:
>
> (1) The patch -- correctly -- no longer touches CpuHotplugSmm, so please
> remove "/CpuHotplugSmm" from the subject line.
>
>
>>
>> diff --git a/OvmfPkg/OvmfPkg.dec b/OvmfPkg/OvmfPkg.dec
>> index 4348bb45c64a..9629707020ba 100644
>> --- a/OvmfPkg/OvmfPkg.dec
>> +++ b/OvmfPkg/OvmfPkg.dec
>> @@ -352,6 +352,10 @@ [PcdsDynamic, PcdsDynamicEx]
>> # This PCD is only accessed if PcdSmmSmramRequire is TRUE (see below).
>> gUefiOvmfPkgTokenSpaceGuid.PcdQ35SmramAtDefaultSmbase|FALSE|BOOLEAN|0x34
>>
>> + ## This PCD adds a communication channel between OVMF's SmmCpuFeaturesLib
>> + # instance in PiSmmCpuDxeSmm, and CpuHotplugSmm.
>> + gUefiOvmfPkgTokenSpaceGuid.PcdCpuHotEjectDataAddress|0|UINT64|0x46
>> +
>> [PcdsFeatureFlag]
>> gUefiOvmfPkgTokenSpaceGuid.PcdQemuBootOrderPciTranslation|TRUE|BOOLEAN|0x1c
>> gUefiOvmfPkgTokenSpaceGuid.PcdQemuBootOrderMmioTranslation|FALSE|BOOLEAN|0x1d
>> diff --git a/OvmfPkg/Include/Pcd/CpuHotEjectData.h b/OvmfPkg/Include/Pcd/CpuHotEjectData.h
>> new file mode 100644
>> index 000000000000..024a92726869
>> --- /dev/null
>> +++ b/OvmfPkg/Include/Pcd/CpuHotEjectData.h
>> @@ -0,0 +1,52 @@
>> +/** @file
>> + Definition for the CPU_HOT_EJECT_DATA structure, which shares
>> + CPU hot-eject state between OVMF's SmmCpuFeaturesLib instance in
>> + PiSmmCpuDxeSmm, and CpuHotplugSmm.
>> +
>> + CPU_HOT_EJECT_DATA is allocated in SMRAM, and pointed-to by
>> + PcdCpuHotEjectDataAddress.
>> +
>> + PcdCpuHotEjectDataAddress is valid when SMM_REQUIRE is TRUE
>> + and MaxNumberOfCpus > 1.
>
> (2) Looks good, thanks; please clarify it as follows though:
>
> s/MaxNumberOfCpus/PcdCpuMaxLogicalProcessorNumber/
>
>
>> +
>> + Copyright (C) 2021, Oracle Corporation.
>> +
>> + SPDX-License-Identifier: BSD-2-Clause-Patent
>> +**/
>> +
>> +#ifndef CPU_HOT_EJECT_DATA_H_
>> +#define CPU_HOT_EJECT_DATA_H_
>> +
>> +/**
>> + CPU Hot-eject handler, called from SmmCpuFeaturesRendezvousExit()
>> + on each CPU at exit from SMM.
>> +
>> + @param[in] ProcessorNum ProcessorNum denotes the CPU exiting SMM,
>> + and will be used as an index into
>> + CPU_HOT_EJECT_DATA->QemuSelectorMap. It is
>> + identical to the processor handle in
>> + EFI_SMM_CPU_SERVICE_PROTOCOL.
>> +**/
>> +typedef
>> +VOID
>> +(EFIAPI *CPU_HOT_EJECT_HANDLER) (
>> + IN UINTN ProcessorNum
>> + );
>> +
>> +//
>> +// CPU_EJECT_QEMU_SELECTOR_INVALID marks CPUs not being ejected in
>> +// CPU_HOT_EJECT_DATA->QemuSelectorMap.
>> +//
>> +// QEMU CPU Selector is UINT32, so we choose an invalid value larger
>> +// than that type.
>> +//
>> +#define CPU_EJECT_QEMU_SELECTOR_INVALID (MAX_UINT64)
>> +
>> +typedef struct {
>> + volatile UINT64 *QemuSelectorMap; // Maps ProcessorNum -> QemuSelector
>> + // for pending hot-ejects
>> + volatile CPU_HOT_EJECT_HANDLER Handler; // Handler to do the CPU ejection
>> + UINT32 ArrayLength; // Entries in the QemuSelectorMap
>
Acking the comments above.
> (3) Please move "*QemuSelectorMap" and "ArrayLength" to the right, by 9
> spaces, so that they line up with "Handler".
>
> Now... I realize that such an update would result in the awkwarly wide
> code snippet:
>
>> typedef struct {
>> volatile UINT64 *QemuSelectorMap; // Maps ProcessorNum -> QemuSelector
>> // for pending hot-ejects
>> volatile CPU_HOT_EJECT_HANDLER Handler; // Handler to do the CPU ejection
>> UINT32 ArrayLength; // Entries in the QemuSelectorMap
>> };
>
> where it is not really possible to re-wrap the comments usefully. With
> that in mind, the following is likely the best approach:
>
>> typedef struct {
>> //
>> // Maps ProcessorNum -> QemuSelector for pending hot-ejects
>> //
>> volatile UINT64 *QemuSelectorMap;
>> //
>> // Handler to do the CPU ejection
>> //
>> volatile CPU_HOT_EJECT_HANDLER Handler;
>> //
>> // Entries in the QemuSelectorMap
>> //
>> UINT32 ArrayLength;
>> };
>
> This way, you have ample room for the comments. Plus, the field names
> need not care about any visual alignment, because they are separated by
> the comments anyway.
Thanks for clarifying. I was wondering if this comment style is
fine for data structures or not. Should have checked other code.
Thanks
Ankur
>
> Thanks!
> Laszlo
>
>> +} CPU_HOT_EJECT_DATA;
>> +
>> +#endif // CPU_HOT_EJECT_DATA_H_
>>
>
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