Re: [PATCH v2 28/29] drm/xe: Add always_migrate_to_vram modparam

[Matthew Brost <matthew.brost@intel.com>]

On Mon, Dec 02, 2024 at 01:40:20PM +0100, Thomas Hellström wrote:
> On Tue, 2024-10-15 at 20:25 -0700, Matthew Brost wrote:
> > Used to show we can bounce memory multiple times.
> > 
> > Signed-off-by: Matthew Brost <matthew.brost@intel.com>
> > ---
> >  drivers/gpu/drm/xe/xe_module.c | 7 +++++++
> >  drivers/gpu/drm/xe/xe_module.h | 1 +
> >  drivers/gpu/drm/xe/xe_svm.c    | 3 +++
> >  3 files changed, 11 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/xe/xe_module.c
> > b/drivers/gpu/drm/xe/xe_module.c
> > index 77ce9f9ca7a5..088f6caea307 100644
> > --- a/drivers/gpu/drm/xe/xe_module.c
> > +++ b/drivers/gpu/drm/xe/xe_module.c
> > @@ -25,9 +25,16 @@ struct xe_modparam xe_modparam = {
> >  	.max_vfs = IS_ENABLED(CONFIG_DRM_XE_DEBUG) ? ~0 : 0,
> >  #endif
> >  	.wedged_mode = 1,
> > +	.svm_notifier_size = 512,
> >  	/* the rest are 0 by default */
> >  };
> >  
> > +module_param_named(svm_notifier_size, xe_modparam.svm_notifier_size,
> > uint, 0600);
> > +MODULE_PARM_DESC(svm_notifier_size, "Set the svm notifier size(in
> > MiB), must be pow2");
> 
> Ah, this should probably have been in the previous patch?

Yes.

> pow2 could be spelled out "a power of 2"?

And yes.

> 
> 
> > +
> > +module_param_named(always_migrate_to_vram,
> > xe_modparam.always_migrate_to_vram, bool, 0444);
> > +MODULE_PARM_DESC(always_migrate_to_vram, "Always migrate to VRAM on
> > GPU fault");
> > +
> >  module_param_named_unsafe(force_execlist,
> > xe_modparam.force_execlist, bool, 0444);
> >  MODULE_PARM_DESC(force_execlist, "Force Execlist submission");
> >  
> > diff --git a/drivers/gpu/drm/xe/xe_module.h
> > b/drivers/gpu/drm/xe/xe_module.h
> > index 5a3bfea8b7b4..84339e509c80 100644
> > --- a/drivers/gpu/drm/xe/xe_module.h
> > +++ b/drivers/gpu/drm/xe/xe_module.h
> > @@ -12,6 +12,7 @@
> >  struct xe_modparam {
> >  	bool force_execlist;
> >  	bool probe_display;
> > +	bool always_migrate_to_vram;
> 
> Kerneldoc
>

Will add.

Matt
 
> Thanks,
> Thomas
> 
> 
> >  	u32 force_vram_bar_size;
> >  	int guc_log_level;
> >  	char *guc_firmware_path;
> > diff --git a/drivers/gpu/drm/xe/xe_svm.c
> > b/drivers/gpu/drm/xe/xe_svm.c
> > index 16e34aaead79..bb386f56a189 100644
> > --- a/drivers/gpu/drm/xe/xe_svm.c
> > +++ b/drivers/gpu/drm/xe/xe_svm.c
> > @@ -767,6 +767,9 @@ int xe_svm_handle_pagefault(struct xe_vm *vm,
> > struct xe_vma *vma,
> >  	}
> >  	drm_exec_fini(&exec);
> >  
> > +	if (xe_modparam.always_migrate_to_vram)
> > +		range->migrated = false;
> > +
> >  	dma_fence_wait(fence, false);
> >  	dma_fence_put(fence);
> >  
>