[Intel-xe] [PATCH v5] Documentation/gpu: VM_BIND locking document

[Thomas Hellström]

On Mon, 2023-11-27 at 14:36 -0500, Rodrigo Vivi wrote:
> On Tue, Nov 21, 2023 at 11:40:46AM +0100, Thomas Hellström wrote:
> > Add the first version of the VM_BIND locking document which is
> > intended to be part of the xe driver upstreaming agreement.
> > 
> > The document describes and discuss the locking used during exec-
> > functions, evicton and for userptr gpu-vmas. Intention is to be
> > using the
> > same nomenclature as the drm-vm-bind-async.rst.
> > 
> > v2:
> > - s/gvm/gpu_vm/g (Rodrigo Vivi)
> > - Clarify the userptr seqlock with a pointer to mm/mmu_notifier.c
> >   (Rodrigo Vivi)
> > - Adjust commit message accordingly.
> > - Add SPDX license header.
> > 
> > v3:
> > - Large update to align with the drm_gpuvm manager locking
> > - Add "Efficient userptr gpu_vma exec function iteration" section
> > - Add "Locking at bind- and unbind time" section.
> > 
> > v4:
> > - Fix tabs vs space errors by untabifying (Rodrigo Vivi)
> > - Minor style fixes and typos (Rodrigo Vivi)
> > - Clarify situations where stale GPU mappings are occurring and how
> >   access through these mappings are blocked. (Rodrigo Vivi)
> > - Insert into the toctree in implementation_guidelines.rst
> > 
> > v5:
> > - Add a section about recoverable page-faults.
> > - Use local references to other documentation where possible
> >   (Bagas Sanjaya)
> > - General documentation fixes and typos (Danilo Krummrich and
> >   Boris Brezillon)
> > - Improve the documentation around locks that need to be grabbed
> > from the
> >   dm-fence critical section (Boris Brezillon)
> > - Add more references to the DRM GPUVM helpers (Danilo Krummrich
> > and
> >   Boriz Brezillon)
> > - Update the rfc/xe.rst document.
> > 
> > Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> > Signed-off-by: Thomas Hellström <thomas.hellstrom at linux.intel.com>
> 
> First of all, with Bagas and Boris latest suggestions, already few
> free to use:
> 
> Reviewed-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
> 
> But a few minor comments below. Mostly trying to address Boris
> feeling
> of long sentences. However, take them with a grain of salt since I'm
> not
> a native english speaker. :) 

Hi, Rodrigo.

Thanks for the reviewing. I've added most but not all of the
suggestions in v6. Regarding the comment about "zapping", that's used
by the core mm for the process of unmapping page-table entries;
zap_vma_ptes() etc. Merely following that, although I'm not really
against using unmapping etc.

/Thomas