Re: [PATCH 0/5] MR3103: server: Create and use a desktop shared mapping for GetCursorPos.

[Jinoh Kang (＠iamahuman)]

Jinoh Kang (@iamahuman) commented about server/queue.c:
> -
>
> +#define SHARED_WRITE_BEGIN( x )                                         \
> - do {                                                                \
> -
>    assert( (*(x) & SEQUENCE_MASK) != SEQUENCE_MASK );              \
> -
>    if ((__atomic_add_fetch( x, 1, __ATOMIC_RELAXED ) & SEQUENCE_MASK) == 1) \
> -
>        __atomic_thread_fence( __ATOMIC_RELEASE );                  \
> - } while(0)
> -
>
> +#define SHARED_WRITE_END( x )                                           \
> - do {                                                                \
> -
>    assert( (*(x) & SEQUENCE_MASK) != 0 );                          \
> -
>    if ((*(x) & SEQUENCE_MASK) > 1)                                 \
> -
>        __atomic_sub_fetch( x, 1, __ATOMIC_RELAXED );               \
> -
>    else {                                                          \
> -
>        __atomic_thread_fence( __ATOMIC_RELEASE );                  \
> -
>        __atomic_add_fetch( x, SEQUENCE_MASK, __ATOMIC_RELAXED );   \

Can we just coalesce these two calls into one for better optimization opportunities (e.g., use of STLR with RCpc semantics on ARM64, instead of `DMB ISH`)?

```suggestion:-1+0
            __atomic_add_fetch( x, SEQUENCE_MASK, __ATOMIC_RELEASE );   \
```