Re: [PATCH] xen: Drop xenoprofile support

["Teddy Astie" <teddy.astie@xxxxxxxxxx>]

Le 05/01/2026 à 21:01, Andrew Cooper a écrit :
> The most recent xenoprof change was 300ef0cb4fde ("x86: Add Xenoprofile
> support for AMD Family16h") in 2013, despite there being 42 changes worth of
> other cleanup/rearranging since then.
>
> Oprofile themselves dropped Xen support in commit 0c142c3a096d ("Remove
> opcontrol and the GUI and processor models dependent on it") in 2014, as part
> of releasing version 1.0 and switching over to using operf based on the Linux
> perf_event subsystem.  Linux's version of this patch was merged in commit
> 24880bef417f ("Merge tag 'oprofile-removal-5.12'") in 2021.
>
> Drop xenoprof and all supporting infrastructure, including the hypercall, the
> XSM hook and flask vectors which lose their only caller, and even shrinks
> struct domain by one pointer which wasn't properly excluded in
> !CONFIG_XENOPROF builds.
>
> Retain the public xenoprof.h header as it is ABI, but note that the
> functionality is removed.
>
> Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> ---
> CC: Anthony PERARD <anthony.perard@xxxxxxxxxx>
> CC: Michal Orzel <michal.orzel@xxxxxxx>
> CC: Jan Beulich <jbeulich@xxxxxxxx>
> CC: Julien Grall <julien@xxxxxxx>
> CC: Roger Pau Monné <roger.pau@xxxxxxxxxx>
> CC: Stefano Stabellini <sstabellini@xxxxxxxxxx>
> CC: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
> CC: Daniel P. Smith <dpsmith@xxxxxxxxxxxxxxxxxxxx>
>
> Despite appearing to be architecture neutral, the internals of Xenoprof were
> entirely x86-specific.  Another curiosity is that only the VMX MSR hooks
> called passive_domain_do_{rd,wr}msr(), and I can't see how this was correct
> for SVM.
>
> The real reason for finally getting around to this is the number of MISRA
> violations reported by the eclair-x86_64-allcode job that I don't feel like
> fixing.
> ---
>   CHANGELOG.md                            |   3 +
>   docs/misc/xen-command-line.pandoc       |   6 -
>   tools/flask/policy/modules/dom0.te      |   2 -
>   xen/arch/x86/Makefile                   |   1 -
>   xen/arch/x86/cpu/vpmu_amd.c             |   7 -
>   xen/arch/x86/cpu/vpmu_intel.c           |   6 -
>   xen/arch/x86/hvm/svm/entry.S            |   1 -
>   xen/arch/x86/hvm/svm/svm.c              |   2 -
>   xen/arch/x86/hvm/vmx/vmx.c              |   9 -
>   xen/arch/x86/include/asm/xenoprof.h     |  95 ---
>   xen/arch/x86/oprofile/Makefile          |   6 -
>   xen/arch/x86/oprofile/backtrace.c       | 145 ----
>   xen/arch/x86/oprofile/nmi_int.c         | 485 ------------
>   xen/arch/x86/oprofile/op_counter.h      |  41 -
>   xen/arch/x86/oprofile/op_model_athlon.c | 547 -------------
>   xen/arch/x86/oprofile/op_model_p4.c     | 721 -----------------
>   xen/arch/x86/oprofile/op_model_ppro.c   | 348 ---------
>   xen/arch/x86/oprofile/op_x86_model.h    |  58 --
>   xen/arch/x86/oprofile/xenoprof.c        | 106 ---
>   xen/arch/x86/traps.c                    |   4 -
>   xen/common/Kconfig                      |  11 -
>   xen/common/Makefile                     |   1 -
>   xen/common/compat/xenoprof.c            |  42 -
>   xen/common/domain.c                     |   6 -
>   xen/common/xenoprof.c                   | 977 ------------------------
>   xen/include/Makefile                    |   1 -
>   xen/include/hypercall-defs.c            |   6 -
>   xen/include/public/xen.h                |   2 +-
>   xen/include/public/xenoprof.h           |   2 +-
>   xen/include/xen/sched.h                 |   3 -
>   xen/include/xen/xenoprof.h              |  49 --
>   xen/include/xsm/dummy.h                 |   7 -
>   xen/include/xsm/xsm.h                   |   7 -
>   xen/xsm/dummy.c                         |   2 -
>   xen/xsm/flask/hooks.c                   |  35 -
>   xen/xsm/flask/policy/access_vectors     |   4 -
>   36 files changed, 5 insertions(+), 3743 deletions(-)
>   delete mode 100644 xen/arch/x86/include/asm/xenoprof.h
>   delete mode 100644 xen/arch/x86/oprofile/Makefile
>   delete mode 100644 xen/arch/x86/oprofile/backtrace.c
>   delete mode 100644 xen/arch/x86/oprofile/nmi_int.c
>   delete mode 100644 xen/arch/x86/oprofile/op_counter.h
>   delete mode 100644 xen/arch/x86/oprofile/op_model_athlon.c
>   delete mode 100644 xen/arch/x86/oprofile/op_model_p4.c
>   delete mode 100644 xen/arch/x86/oprofile/op_model_ppro.c
>   delete mode 100644 xen/arch/x86/oprofile/op_x86_model.h
>   delete mode 100644 xen/arch/x86/oprofile/xenoprof.c
>   delete mode 100644 xen/common/compat/xenoprof.c
>   delete mode 100644 xen/common/xenoprof.c
>   delete mode 100644 xen/include/xen/xenoprof.h
>
> diff --git a/xen/include/public/xen.h b/xen/include/public/xen.h
> index 7f15204c3885..b12fd10e6315 100644
> --- a/xen/include/public/xen.h
> +++ b/xen/include/public/xen.h
> @@ -106,7 +106,7 @@ DEFINE_XEN_GUEST_HANDLE(xen_ulong_t);
>   #define __HYPERVISOR_nmi_op               28
>   #define __HYPERVISOR_sched_op             29
>   #define __HYPERVISOR_callback_op          30
> -#define __HYPERVISOR_xenoprof_op          31
> +#define __HYPERVISOR_xenoprof_op          31 /* Dropped in Xen 4.22 */
>   #define __HYPERVISOR_event_channel_op     32
>   #define __HYPERVISOR_physdev_op           33
>   #define __HYPERVISOR_hvm_op               34
> diff --git a/xen/include/public/xenoprof.h b/xen/include/public/xenoprof.h
> index 2298b6759ed3..f97a67042e07 100644
> --- a/xen/include/public/xenoprof.h
> +++ b/xen/include/public/xenoprof.h
> @@ -3,7 +3,7 @@
>    * xenoprof.h
>    *
>    * Interface for enabling system wide profiling based on hardware 
> performance
> - * counters
> + * counters.  Dropped from Xen in 4.22.
>    *
>    * Copyright (C) 2005 Hewlett-Packard Co.
>    * Written by Aravind Menon & Jose Renato Santos

Reviewed-by: Teddy Astie <teddy.astie@xxxxxxxxxx>

Some question: do we plan to drop xenoprof.h headers at some point (even
if not today) ?

Teddy




--
Teddy Astie | Vates XCP-ng Developer

XCP-ng & Xen Orchestra - Vates solutions

web: https://vates.tech