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[v14,00/12] Parallel CPU bringup for x86_64

Message ID 20230308171328.1562857-1-usama.arif@bytedance.com (mailing list archive)
Headers show
Series Parallel CPU bringup for x86_64 | expand

Message

Usama Arif March 8, 2023, 5:13 p.m. UTC
The main code change over v13 is to enable parallel bringup for SEV-ES guests.

Thanks,
Usama

Changes across versions:
v2: Cut it back to just INIT/SIPI/SIPI in parallel for now, nothing more
v3: Clean up x2apic patch, add MTRR optimisation, lock topology update
    in preparation for more parallelisation.
v4: Fixes to the real mode parallelisation patch spotted by SeanC, to
    avoid scribbling on initial_gs in common_cpu_up(), and to allow all
    24 bits of the physical X2APIC ID to be used. That patch still needs
    a Signed-off-by from its original author, who once claimed not to
    remember writing it at all. But now we've fixed it, hopefully he'll
    admit it now :)
v5: rebase to v6.1 and remeasure performance, disable parallel bringup
    for AMD CPUs.
v6: rebase to v6.2-rc6, disabled parallel boot on amd as a cpu bug and
    reused timer calibration for secondary CPUs.
v7: [David Woodhouse] iterate over all possible CPUs to find any existing
    cluster mask in alloc_clustermask. (patch 1/9)
    Keep parallel AMD support enabled in AMD, using APIC ID in CPUID leaf
    0x0B (for x2APIC mode) or CPUID leaf 0x01 where 8 bits are sufficient.
    Included sanity checks for APIC id from 0x0B. (patch 6/9)
    Removed patch for reusing timer calibration for secondary CPUs.
    commit message and code improvements.
v8: Fix CPU0 hotplug by setting up the initial_gs, initial_stack and
    early_gdt_descr.
    Drop trampoline lock and bail if APIC ID not found in find_cpunr.
    Code comments improved and debug prints added.
v9: Drop patch to avoid repeated saves of MTRR at boot time.
    rebased and retested at v6.2-rc8.
    added kernel doc for no_parallel_bringup and made do_parallel_bringup
    __ro_after_init.
v10: Fixed suspend/resume not working with parallel smpboot.
     rebased and retested to 6.2.
     fixed checkpatch errors.
v11: Added patches from Brian Gerst to remove the global variables initial_gs,
     initial_stack, and early_gdt_descr from the 64-bit boot code
     (https://lore.kernel.org/all/20230222221301.245890-1-brgerst@gmail.com/).
v12: Fixed compilation errors, acquire tr_lock for every stack setup in
     trampoline_64.S.
     Rearranged commits for a cleaner git history.
v13: Fix build error with CONFIG_FORCE_NR_CPUS.
     Commit message improved, typos fixed and extra comments added.
v14: Enable parallel bringup for SEV-ES guests
 
Brian Gerst (3):
  x86/smpboot: Remove initial_stack on 64-bit
  x86/smpboot: Remove early_gdt_descr on 64-bit
  x86/smpboot: Remove initial_gs

David Woodhouse (9):
  x86/apic/x2apic: Allow CPU cluster_mask to be populated in parallel
  cpu/hotplug: Move idle_thread_get() to <linux/smpboot.h>
  cpu/hotplug: Add dynamic parallel bringup states before
    CPUHP_BRINGUP_CPU
  x86/smpboot: Reference count on smpboot_setup_warm_reset_vector()
  x86/smpboot: Split up native_cpu_up into separate phases and document
    them
  x86/smpboot: Support parallel startup of secondary CPUs
  x86/smpboot: Send INIT/SIPI/SIPI to secondary CPUs in parallel
  x86/smpboot: Serialize topology updates for secondary bringup
  x86/smpboot: Allow parallel bringup for SEV-ES

 .../admin-guide/kernel-parameters.txt         |   3 +
 arch/x86/include/asm/cpu.h                    |   1 +
 arch/x86/include/asm/processor.h              |   6 +-
 arch/x86/include/asm/realmode.h               |   4 +-
 arch/x86/include/asm/sev-common.h             |   3 +
 arch/x86/include/asm/sev.h                    |   5 +
 arch/x86/include/asm/smp.h                    |  18 +-
 arch/x86/include/asm/topology.h               |   2 -
 arch/x86/kernel/acpi/sleep.c                  |  30 +-
 arch/x86/kernel/apic/apic.c                   |   2 +-
 arch/x86/kernel/apic/x2apic_cluster.c         | 126 +++---
 arch/x86/kernel/asm-offsets.c                 |   1 +
 arch/x86/kernel/cpu/common.c                  |   6 +-
 arch/x86/kernel/cpu/topology.c                |   2 +-
 arch/x86/kernel/head_64.S                     | 162 ++++++--
 arch/x86/kernel/smpboot.c                     | 366 +++++++++++++-----
 arch/x86/realmode/init.c                      |   3 +
 arch/x86/realmode/rm/trampoline_64.S          |  27 +-
 arch/x86/xen/smp_pv.c                         |   4 +-
 arch/x86/xen/xen-head.S                       |   2 +-
 include/linux/cpuhotplug.h                    |   2 +
 include/linux/smpboot.h                       |   7 +
 kernel/cpu.c                                  |  31 +-
 kernel/smpboot.h                              |   2 -
 24 files changed, 614 insertions(+), 201 deletions(-)

Comments

Tor Vic March 10, 2023, 7:20 p.m. UTC | #1
On 08.03.23 17:13, Usama Arif wrote:
> The main code change over v13 is to enable parallel bringup for SEV-ES guests.
> 
> Thanks,
> Usama
> 
> Changes across versions:
> v2: Cut it back to just INIT/SIPI/SIPI in parallel for now, nothing more
> v3: Clean up x2apic patch, add MTRR optimisation, lock topology update
>      in preparation for more parallelisation.
> v4: Fixes to the real mode parallelisation patch spotted by SeanC, to
>      avoid scribbling on initial_gs in common_cpu_up(), and to allow all
>      24 bits of the physical X2APIC ID to be used. That patch still needs
>      a Signed-off-by from its original author, who once claimed not to
>      remember writing it at all. But now we've fixed it, hopefully he'll
>      admit it now :)
> v5: rebase to v6.1 and remeasure performance, disable parallel bringup
>      for AMD CPUs.
> v6: rebase to v6.2-rc6, disabled parallel boot on amd as a cpu bug and
>      reused timer calibration for secondary CPUs.
> v7: [David Woodhouse] iterate over all possible CPUs to find any existing
>      cluster mask in alloc_clustermask. (patch 1/9)
>      Keep parallel AMD support enabled in AMD, using APIC ID in CPUID leaf
>      0x0B (for x2APIC mode) or CPUID leaf 0x01 where 8 bits are sufficient.
>      Included sanity checks for APIC id from 0x0B. (patch 6/9)
>      Removed patch for reusing timer calibration for secondary CPUs.
>      commit message and code improvements.
> v8: Fix CPU0 hotplug by setting up the initial_gs, initial_stack and
>      early_gdt_descr.
>      Drop trampoline lock and bail if APIC ID not found in find_cpunr.
>      Code comments improved and debug prints added.
> v9: Drop patch to avoid repeated saves of MTRR at boot time.
>      rebased and retested at v6.2-rc8.
>      added kernel doc for no_parallel_bringup and made do_parallel_bringup
>      __ro_after_init.
> v10: Fixed suspend/resume not working with parallel smpboot.
>       rebased and retested to 6.2.
>       fixed checkpatch errors.
> v11: Added patches from Brian Gerst to remove the global variables initial_gs,
>       initial_stack, and early_gdt_descr from the 64-bit boot code
>       (https://lore.kernel.org/all/20230222221301.245890-1-brgerst@gmail.com/).
> v12: Fixed compilation errors, acquire tr_lock for every stack setup in
>       trampoline_64.S.
>       Rearranged commits for a cleaner git history.
> v13: Fix build error with CONFIG_FORCE_NR_CPUS.
>       Commit message improved, typos fixed and extra comments added.
> v14: Enable parallel bringup for SEV-ES guests
>   
> Brian Gerst (3):
>    x86/smpboot: Remove initial_stack on 64-bit
>    x86/smpboot: Remove early_gdt_descr on 64-bit
>    x86/smpboot: Remove initial_gs
> 
> David Woodhouse (9):
>    x86/apic/x2apic: Allow CPU cluster_mask to be populated in parallel
>    cpu/hotplug: Move idle_thread_get() to <linux/smpboot.h>
>    cpu/hotplug: Add dynamic parallel bringup states before
>      CPUHP_BRINGUP_CPU
>    x86/smpboot: Reference count on smpboot_setup_warm_reset_vector()
>    x86/smpboot: Split up native_cpu_up into separate phases and document
>      them
>    x86/smpboot: Support parallel startup of secondary CPUs
>    x86/smpboot: Send INIT/SIPI/SIPI to secondary CPUs in parallel
>    x86/smpboot: Serialize topology updates for secondary bringup
>    x86/smpboot: Allow parallel bringup for SEV-ES
> 
>   .../admin-guide/kernel-parameters.txt         |   3 +
>   arch/x86/include/asm/cpu.h                    |   1 +
>   arch/x86/include/asm/processor.h              |   6 +-
>   arch/x86/include/asm/realmode.h               |   4 +-
>   arch/x86/include/asm/sev-common.h             |   3 +
>   arch/x86/include/asm/sev.h                    |   5 +
>   arch/x86/include/asm/smp.h                    |  18 +-
>   arch/x86/include/asm/topology.h               |   2 -
>   arch/x86/kernel/acpi/sleep.c                  |  30 +-
>   arch/x86/kernel/apic/apic.c                   |   2 +-
>   arch/x86/kernel/apic/x2apic_cluster.c         | 126 +++---
>   arch/x86/kernel/asm-offsets.c                 |   1 +
>   arch/x86/kernel/cpu/common.c                  |   6 +-
>   arch/x86/kernel/cpu/topology.c                |   2 +-
>   arch/x86/kernel/head_64.S                     | 162 ++++++--
>   arch/x86/kernel/smpboot.c                     | 366 +++++++++++++-----
>   arch/x86/realmode/init.c                      |   3 +
>   arch/x86/realmode/rm/trampoline_64.S          |  27 +-
>   arch/x86/xen/smp_pv.c                         |   4 +-
>   arch/x86/xen/xen-head.S                       |   2 +-
>   include/linux/cpuhotplug.h                    |   2 +
>   include/linux/smpboot.h                       |   7 +
>   kernel/cpu.c                                  |  31 +-
>   kernel/smpboot.h                              |   2 -
>   24 files changed, 614 insertions(+), 201 deletions(-)
> 

On Linux 6.2, Zen2 and Skylake, no issues or boot problems:

Tested-by: Tor Vic <torvic9@mailbox.org>
Paul Menzel March 10, 2023, 8:18 p.m. UTC | #2
Dear Tor,


Am 10.03.23 um 20:20 schrieb Tor Vic:
> On 08.03.23 17:13, Usama Arif wrote:
>> The main code change over v13 is to enable parallel bringup for SEV-ES 
>> guests.

[…]

>>   .../admin-guide/kernel-parameters.txt         |   3 +
>>   arch/x86/include/asm/cpu.h                    |   1 +
>>   arch/x86/include/asm/processor.h              |   6 +-
>>   arch/x86/include/asm/realmode.h               |   4 +-
>>   arch/x86/include/asm/sev-common.h             |   3 +
>>   arch/x86/include/asm/sev.h                    |   5 +
>>   arch/x86/include/asm/smp.h                    |  18 +-
>>   arch/x86/include/asm/topology.h               |   2 -
>>   arch/x86/kernel/acpi/sleep.c                  |  30 +-
>>   arch/x86/kernel/apic/apic.c                   |   2 +-
>>   arch/x86/kernel/apic/x2apic_cluster.c         | 126 +++---
>>   arch/x86/kernel/asm-offsets.c                 |   1 +
>>   arch/x86/kernel/cpu/common.c                  |   6 +-
>>   arch/x86/kernel/cpu/topology.c                |   2 +-
>>   arch/x86/kernel/head_64.S                     | 162 ++++++--
>>   arch/x86/kernel/smpboot.c                     | 366 +++++++++++++-----
>>   arch/x86/realmode/init.c                      |   3 +
>>   arch/x86/realmode/rm/trampoline_64.S          |  27 +-
>>   arch/x86/xen/smp_pv.c                         |   4 +-
>>   arch/x86/xen/xen-head.S                       |   2 +-
>>   include/linux/cpuhotplug.h                    |   2 +
>>   include/linux/smpboot.h                       |   7 +
>>   kernel/cpu.c                                  |  31 +-
>>   kernel/smpboot.h                              |   2 -
>>   24 files changed, 614 insertions(+), 201 deletions(-)
>>
> 
> On Linux 6.2, Zen2 and Skylake, no issues or boot problems:
> 
> Tested-by: Tor Vic <torvic9@mailbox.org>

Thank you for testing this. It’d be great if you shared the exact timing 
numbers too. (Just to be sure, did you also test ACPI S3 suspend/resume?)


Kind regards,

Paul
Tor Vic March 11, 2023, 7:23 p.m. UTC | #3
On 10.03.23 20:18, Paul Menzel wrote:
> Dear Tor,
> 

Hi Paul,

> 
> Am 10.03.23 um 20:20 schrieb Tor Vic:
>> On 08.03.23 17:13, Usama Arif wrote:
>>> The main code change over v13 is to enable parallel bringup for 
>>> SEV-ES guests.
> 
> […]
> 
>>>   .../admin-guide/kernel-parameters.txt         |   3 +
>>>   arch/x86/include/asm/cpu.h                    |   1 +
>>>   arch/x86/include/asm/processor.h              |   6 +-
>>>   arch/x86/include/asm/realmode.h               |   4 +-
>>>   arch/x86/include/asm/sev-common.h             |   3 +
>>>   arch/x86/include/asm/sev.h                    |   5 +
>>>   arch/x86/include/asm/smp.h                    |  18 +-
>>>   arch/x86/include/asm/topology.h               |   2 -
>>>   arch/x86/kernel/acpi/sleep.c                  |  30 +-
>>>   arch/x86/kernel/apic/apic.c                   |   2 +-
>>>   arch/x86/kernel/apic/x2apic_cluster.c         | 126 +++---
>>>   arch/x86/kernel/asm-offsets.c                 |   1 +
>>>   arch/x86/kernel/cpu/common.c                  |   6 +-
>>>   arch/x86/kernel/cpu/topology.c                |   2 +-
>>>   arch/x86/kernel/head_64.S                     | 162 ++++++--
>>>   arch/x86/kernel/smpboot.c                     | 366 +++++++++++++-----
>>>   arch/x86/realmode/init.c                      |   3 +
>>>   arch/x86/realmode/rm/trampoline_64.S          |  27 +-
>>>   arch/x86/xen/smp_pv.c                         |   4 +-
>>>   arch/x86/xen/xen-head.S                       |   2 +-
>>>   include/linux/cpuhotplug.h                    |   2 +
>>>   include/linux/smpboot.h                       |   7 +
>>>   kernel/cpu.c                                  |  31 +-
>>>   kernel/smpboot.h                              |   2 -
>>>   24 files changed, 614 insertions(+), 201 deletions(-)
>>>
>>
>> On Linux 6.2, Zen2 and Skylake, no issues or boot problems:
>>
>> Tested-by: Tor Vic <torvic9@mailbox.org>
> 
> Thank you for testing this. It’d be great if you shared the exact timing 
> numbers too. (Just to be sure, did you also test ACPI S3 suspend/resume?)
> 

I have just tested suspend/resume on the Zen2 machine, it works.
Not yet tested on the Skylake platform.

What is the best and simplest way to get these timings numbers?

> 
> Kind regards,
> 
> Paul