[Intel-gfx] [PATCH] drm/i915: Don't need a timer to wake us up

[Tvrtko Ursulin]

On 26/11/15 18:24, Chris Wilson wrote:
> On Thu, Nov 26, 2015 at 05:55:39PM +0000, Chris Wilson wrote:
>> On Thu, Nov 26, 2015 at 05:15:46PM +0000, Tvrtko Ursulin wrote:
>>> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>>>
>>> Looks like the sleeping loop in __i915_wait_request can be
>>> simplified by using io_schedule_timeout instead of setting
>>> up and destroying a timer.
>>
>> Simplified by duplicating code? I liked the explicit handling for its
>> obviousness and simplicity.
> To be slightl more gracious, after we eliminate the irq handling from
> this function, the waiter does look like this, albeit I still think it
> is cleaner to keep the timeout handling distinct from the indefinite
> waits.

Duplicating code, fake_irq obviousness and simplicity?!?

To start with:

  drivers/gpu/drm/i915/i915_gem.c | 28 ++++++++--------------------
  1 file changed, 8 insertions(+), 20 deletions(-)

So less code, less binary text, less stack space, less kernel API usage 
so also fewer cycles to execute (not that it matters here but hey), and 
easier to understand logic.

So really I don't know what you don't like about it.

Regards,

Tvrtko