[Intel-gfx] [PATCH 00/29] Replace seqno values with request structures

[John Harrison]

Oops, forgot to update the text for the zero patch. This is no longer 
'work in progress' and is now intended for proper review! The 
description should read as follows:

There is a general feeling that it is better to move away from using a 
simple
integer 'seqno' value to track batch buffer completion. Instead, the request
structure should be used. That provides for much more flexibility going
forwards. Especially which things like a GPU scheduler (which can 
re-order batch
buffers and hence seqnos after submission to the hardware), Android sync 
points
and other such features which potentially make seqno usage more and more
complex.

This patch set does the work of converting most of the driver to use request
structures in preference to seqno values. The only place left that still 
uses
seqnos is the semaphore code. It was decided to leave that alone for the 
time
being as the semaphores are hardware based and the hardware only understands
seqno values.

[Patches against drm-intel-nightly tree fetched 29/10/2014]


On 30/10/2014 18:40, John.C.Harrison at Intel.com wrote:
> From: John Harrison <John.C.Harrison at Intel.com>
>
> Work in progress for replacing seqno usage with requst structures.
>
> There is a general feeling that it is better to move away from using a simple
> integer 'seqno' value to track batch buffer completion. Instead, the request
> structure should be used. That provides for much more flexibility going
> forwards. Especially which things like a GPU scheduler (which can re-order batch
> buffers and hence seqnos after submission to the hardware), Android sync points
> and other such features which potentially make seqno usage more and more
> complex.
>
> The current set of patches do most of the seqno to request structure conversion.
> There are still a couple of direct seqno comparisons in the semaphore code. The
> final conversion of a seqno test into a 'completed' flag inside the request
> structure is still do to as well. Along with whatever changes are required to
> maintain such a flag.
>
> The patches are being posted now to make sure that the various people involved
> agree that it is heading in the right direction.
>
> [Patches against drm-intel-nightly tree fetched 11/09/2014]
>
> John Harrison (29):
>    drm/i915: Remove redundant parameter to i915_gem_object_wait_rendering__tail()
>    drm/i915: Ensure OLS & PLR are always in sync
>    drm/i915: Add reference count to request structure
>    drm/i915: Add helper functions to aid seqno -> request transition
>    drm/i915: Replace last_[rwf]_seqno with last_[rwf]_req
>    drm/i915: Convert i915_gem_ring_throttle to use requests
>    drm/i915: Ensure requests stick around during waits
>    drm/i915: Remove 'outstanding_lazy_seqno'
>    drm/i915: Make 'i915_gem_check_olr' actually check by request not seqno
>    drm/i915: Convert 'last_flip_req' to be a request not a seqno
>    drm/i915: Convert i915_wait_seqno to i915_wait_request
>    drm/i915: Convert __wait_seqno() to __wait_request()
>    drm/i915: Remove obsolete seqno parameter from 'i915_add_request'
>    drm/i915: Convert mmio_flip::seqno to struct request
>    drm/i915: Add IRQ friendly request deference facility
>    drm/i915: Convert 'flip_queued_seqno' into 'flip_queued_request'
>    drm/i915: Convert trace functions from seqno to request
>    drm/i915: Convert 'trace_irq' to use requests rather than seqnos
>    drm/i915: Convert 'ring_idle()' to use requests not seqnos
>    drm/i915: Connect requests to rings at creation not submission
>    drm/i915: Convert 'i915_seqno_passed' calls into 'i915_gem_request_completed'
>    drm/i915: Remove the now redundant 'obj->ring'
>    drm/i915: Cache request completion status
>    drm/i915: Zero fill the request structure
>    drm/i915: Spinlock protection for request list
>    drm/i915: Add uniq id to request structure for debugging
>    drm/i915: Interrupt driven request completion
>    drm/i915: Remove obsolete parameter to i915_gem_request_completed()
>    WIP: Defer seqno allocation until actual hardware submission time
>
>   drivers/gpu/drm/i915/i915_debugfs.c          |   20 +-
>   drivers/gpu/drm/i915/i915_drv.h              |   89 ++++++-
>   drivers/gpu/drm/i915/i915_gem.c              |  356 +++++++++++++++++---------
>   drivers/gpu/drm/i915/i915_gem_context.c      |    3 +-
>   drivers/gpu/drm/i915/i915_gem_execbuffer.c   |   10 +-
>   drivers/gpu/drm/i915/i915_gem_gtt.h          |    4 +-
>   drivers/gpu/drm/i915/i915_gem_render_state.c |    2 +-
>   drivers/gpu/drm/i915/i915_gem_tiling.c       |    2 +-
>   drivers/gpu/drm/i915/i915_gpu_error.c        |    7 +-
>   drivers/gpu/drm/i915/i915_irq.c              |   14 +-
>   drivers/gpu/drm/i915/i915_trace.h            |   47 ++--
>   drivers/gpu/drm/i915/intel_display.c         |   53 ++--
>   drivers/gpu/drm/i915/intel_drv.h             |    4 +-
>   drivers/gpu/drm/i915/intel_lrc.c             |   59 +++--
>   drivers/gpu/drm/i915/intel_overlay.c         |   24 +-
>   drivers/gpu/drm/i915/intel_ringbuffer.c      |   82 +++---
>   drivers/gpu/drm/i915/intel_ringbuffer.h      |   25 +-
>   17 files changed, 505 insertions(+), 296 deletions(-)
>