| Message ID | 20190827231435.398-3-stuart.summers@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add module parameter to reduce engine instances | expand |
Quoting Stuart Summers (2019-08-28 00:14:35) > Add a new module parameter, ring_mask, to allow for disabling > engines during i915 load. This mask follows the intel_engine_id > enum and can be used to hide specified engines from i915 and > from userspace. > > Signed-off-by: Stuart Summers <stuart.summers@intel.com> > --- > drivers/gpu/drm/i915/i915_params.c | 3 +++ > drivers/gpu/drm/i915/i915_params.h | 3 ++- > drivers/gpu/drm/i915/intel_device_info.c | 6 ++++++ > 3 files changed, 11 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c > index 296452f9efe4..6a17fe6ea3a2 100644 > --- a/drivers/gpu/drm/i915/i915_params.c > +++ b/drivers/gpu/drm/i915/i915_params.c > @@ -178,6 +178,9 @@ i915_param_named(enable_gvt, bool, 0400, > "Enable support for Intel GVT-g graphics virtualization host support(default:false)"); > #endif > > +i915_param_named_unsafe(ring_mask, uint, 0400, > + "Mask of engine rings to enable. (default: all supported engines enabled)"); > + > static __always_inline void _print_param(struct drm_printer *p, > const char *name, > const char *type, > diff --git a/drivers/gpu/drm/i915/i915_params.h b/drivers/gpu/drm/i915/i915_params.h > index d29ade3b7de6..d803bf5faac4 100644 > --- a/drivers/gpu/drm/i915/i915_params.h > +++ b/drivers/gpu/drm/i915/i915_params.h > @@ -77,7 +77,8 @@ struct drm_printer; > param(bool, verbose_state_checks, true) \ > param(bool, nuclear_pageflip, false) \ > param(bool, enable_dp_mst, true) \ > - param(bool, enable_gvt, false) > + param(bool, enable_gvt, false) \ > + param(unsigned int, ring_mask, (unsigned int)-1) > > #define MEMBER(T, member, ...) T member; > struct i915_params { > diff --git a/drivers/gpu/drm/i915/intel_device_info.c b/drivers/gpu/drm/i915/intel_device_info.c > index caef01b1da23..f833280f2ef6 100644 > --- a/drivers/gpu/drm/i915/intel_device_info.c > +++ b/drivers/gpu/drm/i915/intel_device_info.c > @@ -993,10 +993,16 @@ void intel_device_info_init_mmio(struct drm_i915_private *dev_priv) > u32 media_fuse; > u16 vdbox_mask; > u16 vebox_mask; > + u32 orig_engine_mask = info->engine_mask; > > if (INTEL_GEN(dev_priv) < 11) > return; > > + info->engine_mask &= i915_modparams.ring_mask; The challenge is we can't use our engine_mask for this as that is an internal bitfield that may change overtime -- and we definitely don't want the modparam to disable different engines on different kernel releases. > + if (info->engine_mask != orig_engine_mask) > + DRM_WARN("loading with reduced engine mask 0x%x\n", > + info->engine_mask); It's operating under direct control from the user, so dev_notice (as we treat it as a quirk). -Chris
On Wed, 2019-08-28 at 10:34 +0100, Chris Wilson wrote: > Quoting Stuart Summers (2019-08-28 00:14:35) > > Add a new module parameter, ring_mask, to allow for disabling > > engines during i915 load. This mask follows the intel_engine_id > > enum and can be used to hide specified engines from i915 and > > from userspace. > > > > Signed-off-by: Stuart Summers <stuart.summers@intel.com> > > --- > > drivers/gpu/drm/i915/i915_params.c | 3 +++ > > drivers/gpu/drm/i915/i915_params.h | 3 ++- > > drivers/gpu/drm/i915/intel_device_info.c | 6 ++++++ > > 3 files changed, 11 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/gpu/drm/i915/i915_params.c > > b/drivers/gpu/drm/i915/i915_params.c > > index 296452f9efe4..6a17fe6ea3a2 100644 > > --- a/drivers/gpu/drm/i915/i915_params.c > > +++ b/drivers/gpu/drm/i915/i915_params.c > > @@ -178,6 +178,9 @@ i915_param_named(enable_gvt, bool, 0400, > > "Enable support for Intel GVT-g graphics virtualization > > host support(default:false)"); > > #endif > > > > +i915_param_named_unsafe(ring_mask, uint, 0400, > > + "Mask of engine rings to enable. (default: all supported > > engines enabled)"); > > + > > static __always_inline void _print_param(struct drm_printer *p, > > const char *name, > > const char *type, > > diff --git a/drivers/gpu/drm/i915/i915_params.h > > b/drivers/gpu/drm/i915/i915_params.h > > index d29ade3b7de6..d803bf5faac4 100644 > > --- a/drivers/gpu/drm/i915/i915_params.h > > +++ b/drivers/gpu/drm/i915/i915_params.h > > @@ -77,7 +77,8 @@ struct drm_printer; > > param(bool, verbose_state_checks, true) \ > > param(bool, nuclear_pageflip, false) \ > > param(bool, enable_dp_mst, true) \ > > - param(bool, enable_gvt, false) > > + param(bool, enable_gvt, false) \ > > + param(unsigned int, ring_mask, (unsigned int)-1) > > > > #define MEMBER(T, member, ...) T member; > > struct i915_params { > > diff --git a/drivers/gpu/drm/i915/intel_device_info.c > > b/drivers/gpu/drm/i915/intel_device_info.c > > index caef01b1da23..f833280f2ef6 100644 > > --- a/drivers/gpu/drm/i915/intel_device_info.c > > +++ b/drivers/gpu/drm/i915/intel_device_info.c > > @@ -993,10 +993,16 @@ void intel_device_info_init_mmio(struct > > drm_i915_private *dev_priv) > > u32 media_fuse; > > u16 vdbox_mask; > > u16 vebox_mask; > > + u32 orig_engine_mask = info->engine_mask; > > > > if (INTEL_GEN(dev_priv) < 11) > > return; > > > > + info->engine_mask &= i915_modparams.ring_mask; > > The challenge is we can't use our engine_mask for this as that is an > internal bitfield that may change overtime -- and we definitely don't > want the modparam to disable different engines on different kernel > releases. Yeah, it's a valid concern. I was thinking we might just put this expectation on the user/debugger given this should really only be used under duress. I'll rethink it and see if I can come up with something a little safer. > > > + if (info->engine_mask != orig_engine_mask) > > + DRM_WARN("loading with reduced engine mask 0x%x\n", > > + info->engine_mask); > > It's operating under direct control from the user, so dev_notice (as > we > treat it as a quirk). Makes sense. I'll make the change in the next revision. Thanks, Stuart > -Chris
diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c index 296452f9efe4..6a17fe6ea3a2 100644 --- a/drivers/gpu/drm/i915/i915_params.c +++ b/drivers/gpu/drm/i915/i915_params.c @@ -178,6 +178,9 @@ i915_param_named(enable_gvt, bool, 0400, "Enable support for Intel GVT-g graphics virtualization host support(default:false)"); #endif +i915_param_named_unsafe(ring_mask, uint, 0400, + "Mask of engine rings to enable. (default: all supported engines enabled)"); + static __always_inline void _print_param(struct drm_printer *p, const char *name, const char *type, diff --git a/drivers/gpu/drm/i915/i915_params.h b/drivers/gpu/drm/i915/i915_params.h index d29ade3b7de6..d803bf5faac4 100644 --- a/drivers/gpu/drm/i915/i915_params.h +++ b/drivers/gpu/drm/i915/i915_params.h @@ -77,7 +77,8 @@ struct drm_printer; param(bool, verbose_state_checks, true) \ param(bool, nuclear_pageflip, false) \ param(bool, enable_dp_mst, true) \ - param(bool, enable_gvt, false) + param(bool, enable_gvt, false) \ + param(unsigned int, ring_mask, (unsigned int)-1) #define MEMBER(T, member, ...) T member; struct i915_params { diff --git a/drivers/gpu/drm/i915/intel_device_info.c b/drivers/gpu/drm/i915/intel_device_info.c index caef01b1da23..f833280f2ef6 100644 --- a/drivers/gpu/drm/i915/intel_device_info.c +++ b/drivers/gpu/drm/i915/intel_device_info.c @@ -993,10 +993,16 @@ void intel_device_info_init_mmio(struct drm_i915_private *dev_priv) u32 media_fuse; u16 vdbox_mask; u16 vebox_mask; + u32 orig_engine_mask = info->engine_mask; if (INTEL_GEN(dev_priv) < 11) return; + info->engine_mask &= i915_modparams.ring_mask; + if (info->engine_mask != orig_engine_mask) + DRM_WARN("loading with reduced engine mask 0x%x\n", + info->engine_mask); + media_fuse = ~I915_READ(GEN11_GT_VEBOX_VDBOX_DISABLE); vdbox_mask = media_fuse & GEN11_GT_VDBOX_DISABLE_MASK;
Add a new module parameter, ring_mask, to allow for disabling engines during i915 load. This mask follows the intel_engine_id enum and can be used to hide specified engines from i915 and from userspace. Signed-off-by: Stuart Summers <stuart.summers@intel.com> --- drivers/gpu/drm/i915/i915_params.c | 3 +++ drivers/gpu/drm/i915/i915_params.h | 3 ++- drivers/gpu/drm/i915/intel_device_info.c | 6 ++++++ 3 files changed, 11 insertions(+), 1 deletion(-)