From 3f4309cbdc8496373875cfce67d7b5dba87c3ccb Mon Sep 17 00:00:00 2001 From: Matthew Auld Date: Wed, 29 Jun 2022 18:43:39 +0100 Subject: [PATCH] drm/i915/uapi: add probed_cpu_visible_size MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Userspace wants to know the size of CPU visible portion of device local-memory, and on small BAR devices the probed_size is no longer enough. In Vulkan, for example, it would like to know the size in bytes for CPU visible VkMemoryHeap. We already track the io_size for each region, so plumb that through to the region query. v2: Drop the ( -1 = unknown ) stuff, which is confusing since nothing can currently ever return such a value. Testcase: igt@i915_query@query-regions-sanity-check Signed-off-by: Matthew Auld Cc: Thomas Hellström Cc: Lionel Landwerlin Cc: Tvrtko Ursulin Cc: Jon Bloomfield Cc: Daniel Vetter Cc: Jordan Justen Cc: Kenneth Graunke Cc: Akeem G Abodunrin Acked-by: Nirmoy Das Reviewed-by: Thomas Hellström Link: https://patchwork.freedesktop.org/patch/msgid/20220629174350.384910-2-matthew.auld@intel.com --- drivers/gpu/drm/i915/i915_query.c | 6 +++ include/uapi/drm/i915_drm.h | 76 +++++++++++++++++-------------- 2 files changed, 48 insertions(+), 34 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_query.c b/drivers/gpu/drm/i915/i915_query.c index 0094f67c63f2..9894add651dd 100644 --- a/drivers/gpu/drm/i915/i915_query.c +++ b/drivers/gpu/drm/i915/i915_query.c @@ -498,6 +498,12 @@ static int query_memregion_info(struct drm_i915_private *i915, info.region.memory_class = mr->type; info.region.memory_instance = mr->instance; info.probed_size = mr->total; + + if (mr->type == INTEL_MEMORY_LOCAL) + info.probed_cpu_visible_size = mr->io_size; + else + info.probed_cpu_visible_size = mr->total; + info.unallocated_size = mr->avail; if (__copy_to_user(info_ptr, &info, sizeof(info))) diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h index de49b68b4fc8..7eacacb00373 100644 --- a/include/uapi/drm/i915_drm.h +++ b/include/uapi/drm/i915_drm.h @@ -3207,36 +3207,6 @@ struct drm_i915_gem_memory_class_instance { * struct drm_i915_memory_region_info - Describes one region as known to the * driver. * - * Note that we reserve some stuff here for potential future work. As an example - * we might want expose the capabilities for a given region, which could include - * things like if the region is CPU mappable/accessible, what are the supported - * mapping types etc. - * - * Note that to extend struct drm_i915_memory_region_info and struct - * drm_i915_query_memory_regions in the future the plan is to do the following: - * - * .. code-block:: C - * - * struct drm_i915_memory_region_info { - * struct drm_i915_gem_memory_class_instance region; - * union { - * __u32 rsvd0; - * __u32 new_thing1; - * }; - * ... - * union { - * __u64 rsvd1[8]; - * struct { - * __u64 new_thing2; - * __u64 new_thing3; - * ... - * }; - * }; - * }; - * - * With this things should remain source compatible between versions for - * userspace, even as we add new fields. - * * Note this is using both struct drm_i915_query_item and struct drm_i915_query. * For this new query we are adding the new query id DRM_I915_QUERY_MEMORY_REGIONS * at &drm_i915_query_item.query_id. @@ -3248,14 +3218,52 @@ struct drm_i915_memory_region_info { /** @rsvd0: MBZ */ __u32 rsvd0; - /** @probed_size: Memory probed by the driver (-1 = unknown) */ + /** + * @probed_size: Memory probed by the driver + * + * Note that it should not be possible to ever encounter a zero value + * here, also note that no current region type will ever return -1 here. + * Although for future region types, this might be a possibility. The + * same applies to the other size fields. + */ __u64 probed_size; - /** @unallocated_size: Estimate of memory remaining (-1 = unknown) */ + /** @unallocated_size: Estimate of memory remaining */ __u64 unallocated_size; - /** @rsvd1: MBZ */ - __u64 rsvd1[8]; + union { + /** @rsvd1: MBZ */ + __u64 rsvd1[8]; + struct { + /** + * @probed_cpu_visible_size: Memory probed by the driver + * that is CPU accessible. + * + * This will be always be <= @probed_size, and the + * remainder (if there is any) will not be CPU + * accessible. + * + * On systems without small BAR, the @probed_size will + * always equal the @probed_cpu_visible_size, since all + * of it will be CPU accessible. + * + * Note this is only tracked for + * I915_MEMORY_CLASS_DEVICE regions (for other types the + * value here will always equal the @probed_size). + * + * Note that if the value returned here is zero, then + * this must be an old kernel which lacks the relevant + * small-bar uAPI support (including + * I915_GEM_CREATE_EXT_FLAG_NEEDS_CPU_ACCESS), but on + * such systems we should never actually end up with a + * small BAR configuration, assuming we are able to load + * the kernel module. Hence it should be safe to treat + * this the same as when @probed_cpu_visible_size == + * @probed_size. + */ + __u64 probed_cpu_visible_size; + }; + }; }; /**