Re: [PATCH] atomics: eliminate mb_read/mb_set

[Richard Henderson <richard.henderson@linaro.org>]

On 5/26/23 01:18, Paolo Bonzini wrote:
> qatomic_mb_read and qatomic_mb_set were the very first atomic primitives
> introduced for QEMU; their semantics are unclear and they provide a false
> sense of safety.
> 
> The last use of qatomic_mb_read() has been removed, so delete it.
> qatomic_mb_set() instead can survive as an optimized
> qatomic_set()+smp_mb(), similar to Linux's smp_store_mb(), but
> rename it to qatomic_set_mb() to match the order of the two
> operations.
> 
> Signed-off-by: Paolo Bonzini<pbonzini@redhat.com>
> ---
>   accel/tcg/cpu-exec.c              |  2 +-
>   accel/tcg/tcg-accel-ops-mttcg.c   |  2 +-
>   accel/tcg/tcg-accel-ops-rr.c      |  4 ++--
>   docs/devel/atomics.rst            | 27 ++++-----------------------
>   include/qemu/atomic.h             |  4 ++--
>   monitor/qmp.c                     |  2 +-
>   softmmu/cpus.c                    |  2 +-
>   softmmu/physmem.c                 |  2 +-
>   target/arm/hvf/hvf.c              |  2 +-
>   tests/unit/test-aio-multithread.c |  2 +-
>   util/qemu-coroutine-lock.c        |  4 ++--
>   11 files changed, 17 insertions(+), 36 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~