Re: [Qemu-devel] [PATCH v4 00/35] cmpxchg-based emulation of atomics

["Alex Bennée" <alex.bennee@linaro.org>]

Richard Henderson <rth@twiddle.net> writes:

> Rebased on top of Paolo's safe-work series, which means
> that we now have cpu_exec_step_atomic for system mode as
> well as linux-user.  This should fix the problems with
> atomic access to notdirty pages that have been reported.
>
> Folded in some feedback from Alex from v3.

I noticed some bits missing from my v3 feedback. I'm assuming the
comments came after you cut this branch?

>
> A complete tree may be found at
>
>   git://github.com/rth7680/qemu.git atomic-4

I've finished my pass of this series. Looking forward to v5, I think we
are pretty good shape for a merge once the final niggles are sorted.
Will you take it in via your tree or through one of the other TCG
maintainers?

>
>
> r~
>
>
> Emilio G. Cota (18):
>   atomics: add atomic_xor
>   atomics: add atomic_op_fetch variants
>   target-i386: emulate LOCK'ed cmpxchg using cmpxchg helpers
>   target-i386: emulate LOCK'ed OP instructions using atomic helpers
>   target-i386: emulate LOCK'ed INC using atomic helper
>   target-i386: emulate LOCK'ed NOT using atomic helper
>   target-i386: emulate LOCK'ed NEG using cmpxchg helper
>   target-i386: emulate LOCK'ed XADD using atomic helper
>   target-i386: emulate LOCK'ed BTX ops using atomic helpers
>   target-i386: emulate XCHG using atomic helper
>   target-i386: remove helper_lock()
>   tests: add atomic_add-bench
>   target-arm: emulate LL/SC using cmpxchg helpers
>   target-arm: emulate SWP with atomic_xchg helper
>   target-arm: emulate aarch64's LL/SC using cmpxchg helpers
>   linux-user: remove handling of ARM's EXCP_STREX
>   linux-user: remove handling of aarch64's EXCP_STREX
>   target-arm: remove EXCP_STREX + cpu_exclusive_{test, info}
>
> Richard Henderson (17):
>   exec: Avoid direct references to Int128 parts
>   int128: Use __int128 if available
>   int128: Add int128_make128
>   tcg: Add EXCP_ATOMIC
>   HACK: Always enable parallel_cpus
>   cputlb: Replace SHIFT with DATA_SIZE
>   cputlb: Move probe_write out of softmmu_template.h
>   cputlb: Remove includes from softmmu_template.h
>   cputlb: Move most of iotlb code out of line
>   cputlb: Tidy some macros
>   tcg: Add atomic helpers
>   tcg: Add atomic128 helpers
>   tcg: Add CONFIG_ATOMIC64
>   tcg: Emit barriers with parallel_cpus
>   target-arm: Rearrange aa32 load and store functions
>   target-alpha: Introduce MMU_PHYS_IDX
>   target-alpha: Emulate LL/SC using cmpxchg helpers
>
>  Makefile.objs              |   1 -
>  Makefile.target            |   1 +
>  atomic_template.h          | 211 +++++++++++++++++++++++++
>  configure                  |  62 +++++++-
>  cpu-exec-common.c          |   6 +
>  cpu-exec.c                 |  30 ++++
>  cpus.c                     |   2 +
>  cputlb.c                   | 203 ++++++++++++++++++++++--
>  exec.c                     |   4 +-
>  include/exec/cpu-all.h     |   1 +
>  include/exec/exec-all.h    |   1 +
>  include/qemu-common.h      |   1 +
>  include/qemu/atomic.h      |  40 ++++-
>  include/qemu/int128.h      | 171 +++++++++++++++++++-
>  linux-user/main.c          | 312 ++++++------------------------------
>  softmmu_template.h         | 104 ++----------
>  target-alpha/cpu.h         |  22 +--
>  target-alpha/helper.c      |  14 +-
>  target-alpha/helper.h      |   9 --
>  target-alpha/machine.c     |   2 -
>  target-alpha/mem_helper.c  |  73 ---------
>  target-alpha/translate.c   | 148 +++++++++--------
>  target-arm/cpu.h           |  17 +-
>  target-arm/helper-a64.c    | 113 +++++++++++++
>  target-arm/helper-a64.h    |   2 +
>  target-arm/internals.h     |   4 +-
>  target-arm/translate-a64.c | 106 ++++++-------
>  target-arm/translate.c     | 342 ++++++++++++++-------------------------
>  target-arm/translate.h     |   4 -
>  target-i386/helper.h       |   4 +-
>  target-i386/mem_helper.c   | 153 ++++++++++++------
>  target-i386/translate.c    | 386 +++++++++++++++++++++++++++++----------------
>  tcg-runtime.c              |  74 +++++++--
>  tcg/tcg-op.c               | 354 +++++++++++++++++++++++++++++++++++++++--
>  tcg/tcg-op.h               |  44 ++++++
>  tcg/tcg-runtime.h          | 109 +++++++++++++
>  tcg/tcg.h                  |  85 ++++++++++
>  tests/.gitignore           |   1 +
>  tests/Makefile.include     |   4 +-
>  tests/atomic_add-bench.c   | 181 +++++++++++++++++++++
>  tests/test-int128.c        |  22 +--
>  translate-all.c            |   1 +
>  42 files changed, 2336 insertions(+), 1088 deletions(-)
>  create mode 100644 atomic_template.h
>  create mode 100644 tests/atomic_add-bench.c


--
Alex Bennée