Re: [PATCH v1 1/1] drm/i915/gt: Move wbvind_on_all_cpus #define

["Cheng, Michael" <michael.cheng@xxxxxxxxx>]

Thanks for the feedback! Another idea  I had that kind of align to what you are suggesting is adding a wrapper for wbinvd_on_all_cpus within drm_cache.h, then having it be included in the three files that calls this function. Thoughts on that?

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From: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>
Sent: Friday, February 11, 2022 5:33:37 AM
To: Cheng, Michael <michael.cheng@xxxxxxxxx>; intel-gfx@xxxxxxxxxxxxxxxxxxxxx <intel-gfx@xxxxxxxxxxxxxxxxxxxxx>
Cc: tvrtko.ursulin@xxxxxxxxxxxxxxx <tvrtko.ursulin@xxxxxxxxxxxxxxx>; Cheng, Michael <michael.cheng@xxxxxxxxx>; Vivekanandan, Balasubramani <balasubramani.vivekanandan@xxxxxxxxx>; Boyer, Wayne <wayne.boyer@xxxxxxxxx>; Bowman, Casey G <casey.g.bowman@xxxxxxxxx>; De Marchi, Lucas <lucas.demarchi@xxxxxxxxx>; dri-devel@xxxxxxxxxxxxxxxxxxxxx <dri-devel@xxxxxxxxxxxxxxxxxxxxx>
Subject: Re: [PATCH v1 1/1] drm/i915/gt: Move wbvind_on_all_cpus #define

 

On Thu, 10 Feb 2022, Michael Cheng <michael.cheng@xxxxxxxxx> wrote:
> Move wbvind_on_all_cpus to intel_gt.h. This will allow other wbind_on_all_cpus
> calls to benefit from the #define logic, and prevent compiler errors
> when building for non-x86 architectures.
>
> Signed-off-by: Michael Cheng <michael.cheng@xxxxxxxxx>
> ---
>  drivers/gpu/drm/i915/gem/i915_gem_pm.c | 7 -------
>  drivers/gpu/drm/i915/gt/intel_gt.h     | 7 +++++++
>  2 files changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_pm.c b/drivers/gpu/drm/i915/gem/i915_gem_pm.c
> index 6da68b38f00f..ff7340ae5ac8 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_pm.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_pm.c
> @@ -12,13 +12,6 @@
> 
>  #include "i915_drv.h"
> 
> -#if defined(CONFIG_X86)
> -#include <asm/smp.h>
> -#else
> -#define wbinvd_on_all_cpus() \
> -     pr_warn(DRIVER_NAME ": Missing cache flush in %s\n", __func__)
> -#endif
> -
>  void i915_gem_suspend(struct drm_i915_private *i915)
>  {
>        GEM_TRACE("%s\n", dev_name(i915->drm.dev));
> diff --git a/drivers/gpu/drm/i915/gt/intel_gt.h b/drivers/gpu/drm/i915/gt/intel_gt.h
> index 2dad46c3eff2..149e8c13e402 100644
> --- a/drivers/gpu/drm/i915/gt/intel_gt.h
> +++ b/drivers/gpu/drm/i915/gt/intel_gt.h
> @@ -10,6 +10,13 @@
>  #include "intel_gt_types.h"
>  #include "intel_reset.h"
> 
> +#if defined(CONFIG_X86)
> +#include <asm/smp.h>
> +#else
> +#define wbinvd_on_all_cpus() \
> +         pr_warn(DRIVER_NAME ": Missing cache flush in %s\n", __func__)
> +#endif

Don't include headers from headers if it can be avoided.

gt/intel_gt.h is included from 79 files. We don't want all of them to
include <asm/smp.h> when only 3 files actually need
wbinvd_on_all_cpus().

Also, gt/intel_gt.h has absolutely nothing to do with
wbinvd_on_all_cpus() or asm/smp.h. Please don't use topical headers as
dumping grounds for random things.

Maybe a better idea is to add a local wrapper for wbinvd_on_all_cpus()
that does the right thing. Or add the above in a dedicated header.


BR,
Jani.


> +
>  struct drm_i915_private;
>  struct drm_printer;

--
Jani Nikula, Intel Open Source Graphics Center