[igt-dev] [PATCH i-g-t v4] tests/i915/gem_exec_schedule.c: Switch to gem_sync and gem_read

[Chris Wilson]

Quoting Antonio Argenziano (2019-02-15 00:49:01)
> use IOCTLs gem_read for reading and, gem_sync to wait on a batch, this
> will help testing platforms that might not expose gtt mapping.
> 
> v2:
>         - use a local helper for reading from BOs. (Chris)
>         - Always sync before reading. (Chris)
> 
> v3:
>         - Better helper naming. (Chris)
>         - Start read from actual offset. (Chris)
> 
> v4:
>         - Always use byte size in helper. (Chris)
> 
> Signed-off-by: Antonio Argenziano <antonio.argenziano at intel.com>
> 
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> @@ -755,8 +759,8 @@ static void deep(int fd, unsigned ring)
>         unsigned int nreq;
>         uint32_t plug;
>         uint32_t result, dep[XS];
> +       uint32_t result_read[size / sizeof(uint32_t)], dep_read[size / sizeof(uint32_t)];

We only use one array at a time, keeping both on stack is overkill. You
might ask why not dep_read[XS][2048]?

>         uint32_t expected = 0;
> -       uint32_t *ptr;
>         uint32_t *ctx;
>         int dep_nreq;
>         int n;

Other than that,
Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
-Chris