[Mesa-dev] [Intel-gfx] [PATCH libdrm v3 1/2] intel: Add EXEC_OBJECT_SUPPORTS_48B_ADDRESS flag
Michel Thierry
michel.thierry at intel.com
Fri Aug 7 04:36:03 PDT 2015
On 8/7/2015 11:56 AM, Michał Winiarski wrote:
> On Fri, Aug 07, 2015 at 10:45:21AM +0100, Michel Thierry wrote:
>> Gen8+ supports 48-bit virtual addresses, but some objects must always be
>> allocated inside the 32-bit address range.
>>
>> In specific, any resource used with flat/heapless (0x00000000-0xfffff000)
>> General State Heap (GSH) or Instruction State Heap (ISH) must be in a
>> 32-bit range, because the General State Offset and Instruction State Offset
>> are limited to 32-bits.
>>
>> The i915 driver has been modified to provide a flag to set when the 4GB
>> limit is not necessary in a given bo (EXEC_OBJECT_SUPPORTS_48B_ADDRESS).
>> 48-bit range will only be used when explicitly requested.
>>
>> Calls to the new drm_intel_bo_emit_reloc_48bit function will have this flag
>> set automatically, while calls to drm_intel_bo_emit_reloc will clear it.
>>
>> v2: Make set/clear functions nops on pre-gen8 platforms, and use them
>> internally in emit_reloc functions (Ben)
>> s/48BADDRESS/48B_ADDRESS/ (Dave)
>> v3: Keep set/clear functions internal, no-one needs to use them directly.
>>
>> References: http://lists.freedesktop.org/archives/intel-gfx/2015-July/072612.html
>> Cc: Ben Widawsky <ben at bwidawsk.net>
>> Cc: Dave Gordon <david.s.gordon at intel.com>
>> Signed-off-by: Michel Thierry <michel.thierry at intel.com>
>> ---
>> include/drm/i915_drm.h | 3 ++-
>> intel/intel_bufmgr.c | 16 ++++++++++++++
>> intel/intel_bufmgr.h | 6 +++++-
>> intel/intel_bufmgr_gem.c | 54 +++++++++++++++++++++++++++++++++++++++++++----
>> intel/intel_bufmgr_priv.h | 11 ++++++++++
>> 5 files changed, 84 insertions(+), 6 deletions(-)
>>
>> diff --git a/include/drm/i915_drm.h b/include/drm/i915_drm.h
>> index ded43b1..426b25c 100644
>> --- a/include/drm/i915_drm.h
>> +++ b/include/drm/i915_drm.h
>> @@ -680,7 +680,8 @@ struct drm_i915_gem_exec_object2 {
>> #define EXEC_OBJECT_NEEDS_FENCE (1<<0)
>> #define EXEC_OBJECT_NEEDS_GTT (1<<1)
>> #define EXEC_OBJECT_WRITE (1<<2)
>> -#define __EXEC_OBJECT_UNKNOWN_FLAGS -(EXEC_OBJECT_WRITE<<1)
>> +#define EXEC_OBJECT_SUPPORTS_48B_ADDRESS (1<<3)
>> +#define __EXEC_OBJECT_UNKNOWN_FLAGS -(EXEC_OBJECT_SUPPORTS_48B_ADDRESS<<1)
>> __u64 flags;
>>
>> __u64 rsvd1;
>> diff --git a/intel/intel_bufmgr.c b/intel/intel_bufmgr.c
>> index 14ea9f9..0bd5191 100644
>> --- a/intel/intel_bufmgr.c
>> +++ b/intel/intel_bufmgr.c
>> @@ -202,6 +202,22 @@ drm_intel_bo_emit_reloc(drm_intel_bo *bo, uint32_t offset,
>> drm_intel_bo *target_bo, uint32_t target_offset,
>> uint32_t read_domains, uint32_t write_domain)
>> {
>> + if (bo->bufmgr->bo_clear_supports_48b_address)
>> + bo->bufmgr->bo_clear_supports_48b_address(target_bo);
>
> This is always true - you assign func to this func pointer unconditionally.
> Also - why not return some meaningful value if the user does not have
> enable_ppgtt=3 set? You can get that from I915_PARAM_HAS_ALIASING_PPGTT right
> now. Check for gen >= 8 seems rather inadequate, and even then you're not
> returning anything useful to the caller.
>
>> +
>> + return bo->bufmgr->bo_emit_reloc(bo, offset,
>> + target_bo, target_offset,
>> + read_domains, write_domain);
>> +}
>> +
>
> Using emit_reloc to set a BO flag seems confusing and can be error prone,
> emit_reloc can be called many times and caller needs to be careful and call the
> right function for each reloc.
>
>> +int
>> +drm_intel_bo_emit_reloc_48bit(drm_intel_bo *bo, uint32_t offset,
>> + drm_intel_bo *target_bo, uint32_t target_offset,
>> + uint32_t read_domains, uint32_t write_domain)
>> +{
>> + if (bo->bufmgr->bo_set_supports_48b_address)
>> + bo->bufmgr->bo_set_supports_48b_address(target_bo);
>
> Same situation as with clear_supports_48b_address.
>
>> +
>> return bo->bufmgr->bo_emit_reloc(bo, offset,
>> target_bo, target_offset,
>> read_domains, write_domain);
>> diff --git a/intel/intel_bufmgr.h b/intel/intel_bufmgr.h
>> index 285919e..8f91ffe 100644
>> --- a/intel/intel_bufmgr.h
>> +++ b/intel/intel_bufmgr.h
>> @@ -87,7 +87,8 @@ struct _drm_intel_bo {
>> /**
>> * Last seen card virtual address (offset from the beginning of the
>> * aperture) for the object. This should be used to fill relocation
>> - * entries when calling drm_intel_bo_emit_reloc()
>> + * entries when calling drm_intel_bo_emit_reloc() or
>> + * drm_intel_bo_emit_reloc_48bit()
>> */
>> uint64_t offset64;
>> };
>> @@ -147,6 +148,9 @@ int drm_intel_bufmgr_check_aperture_space(drm_intel_bo ** bo_array, int count);
>> int drm_intel_bo_emit_reloc(drm_intel_bo *bo, uint32_t offset,
>> drm_intel_bo *target_bo, uint32_t target_offset,
>> uint32_t read_domains, uint32_t write_domain);
>> +int drm_intel_bo_emit_reloc_48bit(drm_intel_bo *bo, uint32_t offset,
>> + drm_intel_bo *target_bo, uint32_t target_offset,
>> + uint32_t read_domains, uint32_t write_domain);
>> int drm_intel_bo_emit_reloc_fence(drm_intel_bo *bo, uint32_t offset,
>> drm_intel_bo *target_bo,
>> uint32_t target_offset,
>> diff --git a/intel/intel_bufmgr_gem.c b/intel/intel_bufmgr_gem.c
>> index 41de396..713ed4e 100644
>> --- a/intel/intel_bufmgr_gem.c
>> +++ b/intel/intel_bufmgr_gem.c
>> @@ -140,6 +140,7 @@ typedef struct _drm_intel_bufmgr_gem {
>> } drm_intel_bufmgr_gem;
>>
>> #define DRM_INTEL_RELOC_FENCE (1<<0)
>> +#define DRM_INTEL_RELOC_SUPPORTS_48B_ADDRESS (2<<0)
>
> Why are you duplicating information about support for 48B in both emit reloc
> function argument and struct bo_gem?
>
>> typedef struct _drm_intel_reloc_target_info {
>> drm_intel_bo *bo;
>> @@ -237,6 +238,14 @@ struct _drm_intel_bo_gem {
>> bool is_userptr;
>>
>> /**
>> + * Boolean of whether this buffer can be in the whole 48-bit address.
>> + *
>> + * By default, buffers will be keep in a 32-bit range, unless this
>> + * flag is explicitly set.
>> + */
>> + bool supports_48b_address;
>> +
>> + /**
>> * Size in bytes of this buffer and its relocation descendents.
>> *
>> * Used to avoid costly tree walking in
>> @@ -463,13 +472,18 @@ drm_intel_add_validate_buffer(drm_intel_bo *bo)
>> }
>>
>> static void
>> -drm_intel_add_validate_buffer2(drm_intel_bo *bo, int need_fence)
>> +drm_intel_add_validate_buffer2(drm_intel_bo *bo, int need_fence,
>> + int supports_48b_address)
>> {
>> drm_intel_bufmgr_gem *bufmgr_gem = (drm_intel_bufmgr_gem *)bo->bufmgr;
>> drm_intel_bo_gem *bo_gem = (drm_intel_bo_gem *)bo;
>> int index;
>>
>> if (bo_gem->validate_index != -1) {
>> + if (supports_48b_address) {
>> + bufmgr_gem->exec2_objects[bo_gem->validate_index].flags |=
>> + EXEC_OBJECT_SUPPORTS_48B_ADDRESS;
>> + }
>> if (need_fence)
>> bufmgr_gem->exec2_objects[bo_gem->validate_index].flags |=
>> EXEC_OBJECT_NEEDS_FENCE;
>> @@ -508,6 +522,10 @@ drm_intel_add_validate_buffer2(drm_intel_bo *bo, int need_fence)
>> bufmgr_gem->exec2_objects[index].flags |=
>> EXEC_OBJECT_NEEDS_FENCE;
>> }
>> + if (supports_48b_address) {
>> + bufmgr_gem->exec2_objects[index].flags |=
>> + EXEC_OBJECT_SUPPORTS_48B_ADDRESS;
>> + }
>> bufmgr_gem->exec_count++;
>> }
>>
>> @@ -1925,11 +1943,33 @@ do_bo_emit_reloc(drm_intel_bo *bo, uint32_t offset,
>> else
>> bo_gem->reloc_target_info[bo_gem->reloc_count].flags = 0;
>>
>> + if (target_bo_gem->supports_48b_address)
>> + bo_gem->reloc_target_info[bo_gem->reloc_count].flags |=
>> + DRM_INTEL_RELOC_SUPPORTS_48B_ADDRESS;
>> +
>> bo_gem->reloc_count++;
>>
>> return 0;
>> }
>>
>> +static void drm_intel_gem_bo_set_supports_48b_address(drm_intel_bo *bo)
>> +{
>> + drm_intel_bufmgr_gem *bufmgr_gem = (drm_intel_bufmgr_gem *) bo->bufmgr;
>> + drm_intel_bo_gem *bo_gem = (drm_intel_bo_gem *) bo;
>> +
>> + if (bufmgr_gem->gen >= 8)
>> + bo_gem->supports_48b_address = 1;
>> +}
>> +
>> +static void drm_intel_gem_bo_clear_supports_48b_address(drm_intel_bo *bo)
>> +{
>> + drm_intel_bufmgr_gem *bufmgr_gem = (drm_intel_bufmgr_gem *) bo->bufmgr;
>> + drm_intel_bo_gem *bo_gem = (drm_intel_bo_gem *) bo;
>> +
>> + if (bufmgr_gem->gen >= 8)
>> + bo_gem->supports_48b_address = 0;
>> +}
>> +
>> static int
>> drm_intel_gem_bo_emit_reloc(drm_intel_bo *bo, uint32_t offset,
>> drm_intel_bo *target_bo, uint32_t target_offset,
>> @@ -2043,7 +2083,7 @@ drm_intel_gem_bo_process_reloc2(drm_intel_bo *bo)
>>
>> for (i = 0; i < bo_gem->reloc_count; i++) {
>> drm_intel_bo *target_bo = bo_gem->reloc_target_info[i].bo;
>> - int need_fence;
>> + int need_fence, supports_48b_addr;
>>
>> if (target_bo == bo)
>> continue;
>> @@ -2056,8 +2096,12 @@ drm_intel_gem_bo_process_reloc2(drm_intel_bo *bo)
>> need_fence = (bo_gem->reloc_target_info[i].flags &
>> DRM_INTEL_RELOC_FENCE);
>>
>> + supports_48b_addr = (bo_gem->reloc_target_info[i].flags &
>> + DRM_INTEL_RELOC_SUPPORTS_48B_ADDRESS);
>> +
>> /* Add the target to the validate list */
>> - drm_intel_add_validate_buffer2(target_bo, need_fence);
>> + drm_intel_add_validate_buffer2(target_bo, need_fence,
>> + supports_48b_addr);
>> }
>> }
>>
>> @@ -2217,7 +2261,7 @@ do_exec2(drm_intel_bo *bo, int used, drm_intel_context *ctx,
>> /* Add the batch buffer to the validation list. There are no relocations
>> * pointing to it.
>> */
>> - drm_intel_add_validate_buffer2(bo, 0);
>> + drm_intel_add_validate_buffer2(bo, 0, 0);
>>
>> memclear(execbuf);
>> execbuf.buffers_ptr = (uintptr_t)bufmgr_gem->exec2_objects;
>> @@ -3299,6 +3343,8 @@ drm_intel_bufmgr_gem_init(int fd, int batch_size)
>> bufmgr_gem->bufmgr.bo_wait_rendering = drm_intel_gem_bo_wait_rendering;
>> bufmgr_gem->bufmgr.bo_emit_reloc = drm_intel_gem_bo_emit_reloc;
>> bufmgr_gem->bufmgr.bo_emit_reloc_fence = drm_intel_gem_bo_emit_reloc_fence;
>> + bufmgr_gem->bufmgr.bo_set_supports_48b_address = drm_intel_gem_bo_set_supports_48b_address;
>> + bufmgr_gem->bufmgr.bo_clear_supports_48b_address = drm_intel_gem_bo_clear_supports_48b_address;
>> bufmgr_gem->bufmgr.bo_pin = drm_intel_gem_bo_pin;
>> bufmgr_gem->bufmgr.bo_unpin = drm_intel_gem_bo_unpin;
>> bufmgr_gem->bufmgr.bo_get_tiling = drm_intel_gem_bo_get_tiling;
>> diff --git a/intel/intel_bufmgr_priv.h b/intel/intel_bufmgr_priv.h
>> index 59ebd18..774fa02 100644
>> --- a/intel/intel_bufmgr_priv.h
>> +++ b/intel/intel_bufmgr_priv.h
>> @@ -152,6 +152,17 @@ struct _drm_intel_bufmgr {
>> void (*destroy) (drm_intel_bufmgr *bufmgr);
>>
>> /**
>> + * Set/Clear 48-bit address support flag in a given bo.
>> + *
>> + * Any resource used with flat/heapless (0x00000000-0xfffff000)
>> + * General State Heap (GSH) or Intructions State Heap (ISH) must
>> + * be in a 32-bit range. 48-bit range will only be used when explicitly
>> + * requested.
>> + */
>> + void (*bo_set_supports_48b_address) (drm_intel_bo *bo);
>> + void (*bo_clear_supports_48b_address) (drm_intel_bo *bo);
>> +
>> + /**
>> * Add relocation entry in reloc_buf, which will be updated with the
>> * target buffer's real offset on on command submission.
>> *
>> --
>> 2.5.0
>
> You also haven't updated the dump_validation_list with proper format specifier
> (addresses are truncated otherwise).
>
> I really don't like hiding set_supports_48b_address/clear_supports_48b_address
> in emit reloc - making this explicit would be a better approach.
> Of course this is just my opinion, but let me post a bit different version of
> this API - just as an RFC so you can see how it would look with explicit set on
> bo and without adding another emit_reloc variant.
>
Hi Michał,
Ben suggested having the set/clear in emit reloc as this is the only
place mesa cares about these wa.
But I see your point, this will be used not only by mesa, so we should
have something that is good for all the other projects.
-Michel
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