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

[Alex Bennée]

Richard Henderson <address@hidden> 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.

Sorry it has taken me so long to get back to this series. Now Paolo's
series has been merged is it worth re-basing? I've hit a number of minor
niggly merge conflicts applying it to master.

>
> Folded in some feedback from Alex from v3.
>
> A complete tree may be found at
>
>   git://github.com/rth7680/qemu.git atomic-4
>
>
> 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