[RFC,v3,00/23] arm cleanup experiment for kvm-only build

Message

Claudio Fontana March 3, 2021, 11:40 a.m. UTC

Here a new version of the series that enables kvm-only builds.

The goal here is to enable the KVM-only build.

The move of kvm code to kvm/ is planned for the next series,
along with the splitting of the accelerator-specific extensions to the
cpu class.

v2 -> v3:

* "target/arm: tcg: add sysemu and user subsirs"
  - new standalone patch to create the empty tcg/sysemu and tcg/user subdirs.

* "target/arm: only build psci for TCG"
  - do not move psci inside tcg/ directory, because HVF might use it soon.
    (Peter)

* "target/arm: move physical address translation"
  - change the module name from "get-phys-addr" to "cpu-mmu",
    which includes aa64_va_parameter in this patch, and that
    will also contain the get_mmu_idx* functions later in the series.
    (Richard)

* "target/arm: split cpregs from tcg/helper.c"
  - moved raw_read and raw_write to cpregs.h (Richard)

* "target/arm: only perform TCG cpu and machine inits if TCG enabled"
  - add an explanatory comment before the kvm function for cpreg list init
  - change the use of g_renew to g_new, since we do not do the double
    initialization of cpreg list anymore.

* "target/arm: add temporary stub for arm_rebuild_hflags"
  - use a if (tcg_enabled()) instead of #ifdef (Richard)

* "target/arm: split vfp state setting from tcg helpers"
  - explain better what goes where in the commit (Richard)

* "target/arm: move arm_mmu_idx*"
  - move the functions to cpu-mmu instead of get-phys-addr (Richard)

* "target/arm: move sve_zcr_len_for_el to common_cpu"

 - add a comment about those functions being in theory
   TARGET_AARCH64 specific, but making the change would spawn
   a large number of additional #ifdefs. This state predates this
   change (Richard).

* "target/arm: move aarch64_sync_32_to_64 (and vv) to cpu code"

 - explain better why these functions are needed for KVM too (Richard)

* "target/arm: move sve_exception_el out of TCG helpers"

 - bring over the sve_exception_el code, making it available for KVM too.
   (Richard)

* "target/arm: wrap call to aarch64_sve_change_el in tcg_enabled()"

 - mention in the commit that this enables finally a build with
   configure --enable-kvm --disable-tcg


v1 -> v2: reworked of the whole series

In this v2, only the first two patches remain, the rest is
reworked.

Main reasons for the rework were:

1) moving out cpregs to its own module, leave the tcg-only part in tcg/

2) split of arm cpu32, cpu64 and cpu models. This is still not perfect,
   but I think it's an improvement.

3) import less stuff, that is actually unused or can be stubbed on KVM
   (thanks to the precious feedback on the previous RFCv1).

...

Main issues:

1) basically needs the "configure only machines compatible with KVM" from Philippe,
   so we can avoid some of the stubs.

2) tests/ work fine building with tcg or with tcg + kvm,
   but for making a kvm-only build pass the tests, more work is needed in tests/
   figuring out which tests are TCG-only and which need to be tweaked.

Thanks a lot for your comments!


. / . / . / . / . / . /


Hi all,

this is an experiment, a cleanup based on and requiring the series
"i386 cleanup PART 2":

https://lists.gnu.org/archive/html/qemu-devel/2021-02/msg05935.html

The goal is to split the code between TCG-only and non-TCG code,
fixing the KVM-only build (configure --disable-tcg),

and laying the ground for further cleanups and the use of the
new accel objects in the hierarchy to specialize the cpu
according to the accelerator.

This is known to be an early state, with probably a lot of work
still needed.

I thought it could be useful to share early, especially in light
of the combination of this with Philippe's work on building
only the machines and devices compatible with KVM for arm.

Comments welcome, thanks,

Claudio


Claudio Fontana (23):
  target/arm: move translate modules to tcg/
  target/arm: move helpers to tcg/
  arm: tcg: only build under CONFIG_TCG
  target/arm: tcg: add sysemu and user subsirs
  target/arm: only build psci for TCG
  target/arm: split off cpu-sysemu.c
  target/arm: move physical address translation to cpu-mmu
  target/arm: split cpregs from tcg/helper.c
  target/arm: move cpu definitions to common cpu module
  target/arm: only perform TCG cpu and machine inits if TCG enabled
  target/arm: kvm: add stubs for some helpers
  target/arm: move cpsr_read, cpsr_write to cpu_common
  target/arm: add temporary stub for arm_rebuild_hflags
  target/arm: split vfp state setting from tcg helpers
  target/arm: move arm_mmu_idx* to cpu-mmu
  target/arm: move sve_zcr_len_for_el to common_cpu
  target/arm: move arm_sctlr away from tcg helpers
  target/arm: move arm_cpu_list to common_cpu
  target/arm: move aarch64_sync_32_to_64 (and vv) to cpu code
  target/arm: split 32bit cpu models from cpu.c to cpu32.c
  target/arm: move sve_exception_el out of TCG helpers
  target/arm: move TCG cpu and models inside tcg/
  target/arm: wrap call to aarch64_sve_change_el in tcg_enabled()

 meson.build                                   |    1 +
 target/arm/cpregs.h                           |  256 +
 target/arm/cpu-mmu.h                          |  118 +
 target/arm/cpu-qom.h                          |    3 -
 target/arm/cpu-vfp.h                          |   29 +
 target/arm/cpu.h                              |  244 +-
 target/arm/cpu32.h                            |   27 +
 target/arm/internals.h                        |   47 +-
 target/arm/{ => tcg}/op_addsub.h              |    0
 target/arm/tcg/tcg-cpu.h                      |   37 +
 target/arm/tcg/trace.h                        |    1 +
 target/arm/{ => tcg}/translate-a64.h          |    0
 target/arm/{ => tcg}/translate.h              |    0
 target/arm/{ => tcg}/vec_internal.h           |    0
 target/arm/{ => tcg}/a32-uncond.decode        |    0
 target/arm/{ => tcg}/a32.decode               |    0
 target/arm/{ => tcg}/m-nocp.decode            |    0
 target/arm/{ => tcg}/neon-dp.decode           |    0
 target/arm/{ => tcg}/neon-ls.decode           |    0
 target/arm/{ => tcg}/neon-shared.decode       |    0
 target/arm/{ => tcg}/sve.decode               |    0
 target/arm/{ => tcg}/t16.decode               |    0
 target/arm/{ => tcg}/t32.decode               |    0
 target/arm/{ => tcg}/vfp-uncond.decode        |    0
 target/arm/{ => tcg}/vfp.decode               |    0
 hw/arm/pxa2xx.c                               |    1 +
 hw/arm/pxa2xx_pic.c                           |    1 +
 hw/intc/arm_gicv3_cpuif.c                     |    1 +
 hw/intc/arm_gicv3_kvm.c                       |    1 +
 target/arm/arm-powerctl.c                     |    8 +-
 target/arm/cpregs.c                           |  363 +
 target/arm/cpu-common.c                       |  319 +
 target/arm/cpu-mmu-sysemu.c                   | 2258 +++++++
 target/arm/cpu-mmu.c                          |  219 +
 target/arm/cpu-sysemu.c                       | 1081 +++
 target/arm/cpu-user.c                         |   40 +
 target/arm/cpu-vfp.c                          |   92 +
 target/arm/cpu.c                              |  931 +--
 target/arm/cpu32.c                            |  512 ++
 target/arm/cpu64.c                            |  133 +-
 target/arm/cpustate-list.c                    |  146 +
 target/arm/gdbstub.c                          |    5 +-
 target/arm/kvm.c                              |   18 +-
 target/arm/kvm/helper-stubs.c                 |   43 +
 target/arm/machine.c                          |   21 +-
 target/arm/{helper.c => tcg/cpregs.c}         | 5829 +----------------
 target/arm/tcg/cpu-vfp.c                      |  146 +
 target/arm/{ => tcg}/crypto_helper.c          |    0
 target/arm/{ => tcg}/debug_helper.c           |    0
 target/arm/{ => tcg}/helper-a64.c             |    0
 target/arm/tcg/helper.c                       | 1521 +++++
 target/arm/{ => tcg}/iwmmxt_helper.c          |    0
 target/arm/{ => tcg}/m_helper.c               |    1 +
 target/arm/{ => tcg}/mte_helper.c             |    0
 target/arm/{ => tcg}/neon_helper.c            |    0
 target/arm/{ => tcg}/op_helper.c              |    1 +
 target/arm/{ => tcg}/pauth_helper.c           |    2 +-
 target/arm/{ => tcg}/sve_helper.c             |    0
 target/arm/tcg/sysemu/tcg-cpu.c               |   73 +
 .../arm/{cpu_tcg.c => tcg/tcg-cpu-models.c}   |   16 +-
 target/arm/tcg/tcg-cpu.c                      |  229 +
 target/arm/{ => tcg}/tlb_helper.c             |    1 +
 target/arm/{ => tcg}/translate-a64.c          |    1 +
 target/arm/{ => tcg}/translate-sve.c          |    0
 target/arm/{ => tcg}/translate.c              |    1 +
 target/arm/{ => tcg}/vec_helper.c             |    0
 target/arm/{ => tcg}/vfp_helper.c             |  210 +-
 target/arm/{ => tcg}/translate-neon.c.inc     |    0
 target/arm/{ => tcg}/translate-vfp.c.inc      |    0
 target/arm/kvm/meson.build                    |    3 +
 target/arm/meson.build                        |   54 +-
 target/arm/tcg/meson.build                    |   45 +
 target/arm/tcg/sysemu/meson.build             |    4 +
 target/arm/tcg/trace-events                   |   10 +
 target/arm/tcg/user/meson.build               |    3 +
 target/arm/trace-events                       |    9 -
 76 files changed, 7819 insertions(+), 7296 deletions(-)
 create mode 100644 target/arm/cpregs.h
 create mode 100644 target/arm/cpu-mmu.h
 create mode 100644 target/arm/cpu-vfp.h
 create mode 100644 target/arm/cpu32.h
 rename target/arm/{ => tcg}/op_addsub.h (100%)
 create mode 100644 target/arm/tcg/tcg-cpu.h
 create mode 100644 target/arm/tcg/trace.h
 rename target/arm/{ => tcg}/translate-a64.h (100%)
 rename target/arm/{ => tcg}/translate.h (100%)
 rename target/arm/{ => tcg}/vec_internal.h (100%)
 rename target/arm/{ => tcg}/a32-uncond.decode (100%)
 rename target/arm/{ => tcg}/a32.decode (100%)
 rename target/arm/{ => tcg}/m-nocp.decode (100%)
 rename target/arm/{ => tcg}/neon-dp.decode (100%)
 rename target/arm/{ => tcg}/neon-ls.decode (100%)
 rename target/arm/{ => tcg}/neon-shared.decode (100%)
 rename target/arm/{ => tcg}/sve.decode (100%)
 rename target/arm/{ => tcg}/t16.decode (100%)
 rename target/arm/{ => tcg}/t32.decode (100%)
 rename target/arm/{ => tcg}/vfp-uncond.decode (100%)
 rename target/arm/{ => tcg}/vfp.decode (100%)
 create mode 100644 target/arm/cpregs.c
 create mode 100644 target/arm/cpu-common.c
 create mode 100644 target/arm/cpu-mmu-sysemu.c
 create mode 100644 target/arm/cpu-mmu.c
 create mode 100644 target/arm/cpu-sysemu.c
 create mode 100644 target/arm/cpu-user.c
 create mode 100644 target/arm/cpu-vfp.c
 create mode 100644 target/arm/cpu32.c
 create mode 100644 target/arm/cpustate-list.c
 create mode 100644 target/arm/kvm/helper-stubs.c
 rename target/arm/{helper.c => tcg/cpregs.c} (60%)
 create mode 100644 target/arm/tcg/cpu-vfp.c
 rename target/arm/{ => tcg}/crypto_helper.c (100%)
 rename target/arm/{ => tcg}/debug_helper.c (100%)
 rename target/arm/{ => tcg}/helper-a64.c (100%)
 create mode 100644 target/arm/tcg/helper.c
 rename target/arm/{ => tcg}/iwmmxt_helper.c (100%)
 rename target/arm/{ => tcg}/m_helper.c (99%)
 rename target/arm/{ => tcg}/mte_helper.c (100%)
 rename target/arm/{ => tcg}/neon_helper.c (100%)
 rename target/arm/{ => tcg}/op_helper.c (99%)
 rename target/arm/{ => tcg}/pauth_helper.c (99%)
 rename target/arm/{ => tcg}/sve_helper.c (100%)
 create mode 100644 target/arm/tcg/sysemu/tcg-cpu.c
 rename target/arm/{cpu_tcg.c => tcg/tcg-cpu-models.c} (99%)
 create mode 100644 target/arm/tcg/tcg-cpu.c
 rename target/arm/{ => tcg}/tlb_helper.c (99%)
 rename target/arm/{ => tcg}/translate-a64.c (99%)
 rename target/arm/{ => tcg}/translate-sve.c (100%)
 rename target/arm/{ => tcg}/translate.c (99%)
 rename target/arm/{ => tcg}/vec_helper.c (100%)
 rename target/arm/{ => tcg}/vfp_helper.c (84%)
 rename target/arm/{ => tcg}/translate-neon.c.inc (100%)
 rename target/arm/{ => tcg}/translate-vfp.c.inc (100%)
 create mode 100644 target/arm/kvm/meson.build
 create mode 100644 target/arm/tcg/meson.build
 create mode 100644 target/arm/tcg/sysemu/meson.build
 create mode 100644 target/arm/tcg/trace-events
 create mode 100644 target/arm/tcg/user/meson.build