Re: [igt-dev] [RFC PATCH v10 4/6] lib: ioctl_wrappers: reach engines by index as well

Tvrtko Ursulin
2019-03-07T14:28:02Z

On 07/03/2019 13:54, Andi Shyti wrote:
> Hi Tvrtko,
>
>>> With the new engine query method engines are reachable through
>>> an index and context they are combined with.
>>>
>>> The 'gem_has_ring()' becomes 'gem_context_has_engine()' that
>>> requires the index that the engine is mapped within the driver.
>>>
>>> The previous 'gem_has_ring()' function becomes a wrapper to the new
>>> 'gem_context_has_engine()'.
>>>
>>> Signed-off-by: Andi Shyti <andi.shyti@intel.com>
>>> ---
>>> lib/ioctl_wrappers.c | 4 +++-
>>> lib/ioctl_wrappers.h | 4 +++-
>>> 2 files changed, 6 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/lib/ioctl_wrappers.c b/lib/ioctl_wrappers.c
>>> index 39920f8707d2..a2597e282704 100644
>>> --- a/lib/ioctl_wrappers.c
>>> +++ b/lib/ioctl_wrappers.c
>>> @@ -1252,7 +1252,7 @@ void igt_require_gem(int fd)
>>> igt_require_f(err == 0, "Unresponsive i915/GEM device\n");
>>> }
>>> -bool gem_has_ring(int fd, unsigned ring)
>>> +bool gem_context_has_engine(int fd, unsigned ring, unsigned ctx)
>>> {
>>> struct drm_i915_gem_execbuffer2 execbuf;
>>> struct drm_i915_gem_exec_object2 exec;
>>> @@ -1268,6 +1268,8 @@ bool gem_has_ring(int fd, unsigned ring)
>>> execbuf.buffers_ptr = to_user_pointer(&exec);
>>> execbuf.buffer_count = 1;
>>> execbuf.flags = ring;
>>> + execbuf.rsvd1 = ctx;
>>> +
>>> return __gem_execbuf(fd, &execbuf) == -ENOENT;
>>> }
>>> diff --git a/lib/ioctl_wrappers.h b/lib/ioctl_wrappers.h
>>> index f0be26080da6..446e973b7449 100644
>>> --- a/lib/ioctl_wrappers.h
>>> +++ b/lib/ioctl_wrappers.h
>>> @@ -142,11 +142,13 @@ bool gem_has_exec_fence(int fd);
>>> /* check functions which auto-skip tests by calling igt_skip() */
>>> void gem_require_caching(int fd);
>>> -bool gem_has_ring(int fd, unsigned ring);
>>> +bool gem_context_has_engine(int fd, unsigned ring, unsigned ctx);
>>> void gem_require_ring(int fd, unsigned ring);
>>> bool gem_has_mocs_registers(int fd);
>>> void gem_require_mocs_registers(int fd);
>>> +#define gem_has_ring(fd, ring) gem_context_has_engine(fd, ring, 0)
>>> +
>>> /* prime */
>>> struct local_dma_buf_sync {
>>> uint64_t flags;
>>>
>>
>> I don't understand why this. All current callers of gem_has_ring pass in eb
>> flags and not an index so how it can work?
>
> This is because of patch 3/6 this makes the for_each_engine2()
> able to work with new and old api.

How does it do that? Maybe I am extra slow today..

How is the for_each_engine2 without a helper to get engine flags, or the
index variable, supposed to be used if one wants to submit a batch to
all engines:

for_each_engine2(...)
eb(engine=??)

Both in legacy and engine discovery mode.

Regards,

Tvrtko

> Have I messed up the patch order?
>
> Andi