Re: [PATCH 05/11] drm/i915: Reduce the pointer dance of i915_is_ggtt()

Tvrtko Ursulin
2015-12-17T11:31:37Z

Hi,

On 14/12/15 11:36, Chris Wilson wrote:
> The multiple levels of indirect do nothing but hinder the compiler and
> the pointer chasing turns to be quite painful but painless to fix.
>
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> ---
> drivers/gpu/drm/i915/i915_debugfs.c | 13 ++++++-------
> drivers/gpu/drm/i915/i915_drv.h | 7 -------
> drivers/gpu/drm/i915/i915_gem.c | 18 +++++++-----------
> drivers/gpu/drm/i915/i915_gem_execbuffer.c | 5 ++---
> drivers/gpu/drm/i915/i915_gem_gtt.c | 12 +++++-------
> drivers/gpu/drm/i915/i915_gem_gtt.h | 5 +++++
> drivers/gpu/drm/i915/i915_trace.h | 27 ++++++++-------------------
> 7 files changed, 33 insertions(+), 54 deletions(-)

Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Regards,

Tvrtko

> diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
> index c04ba9981e9b..9ec133f5af00 100644
> --- a/drivers/gpu/drm/i915/i915_debugfs.c
> +++ b/drivers/gpu/drm/i915/i915_debugfs.c
> @@ -118,7 +118,7 @@ static u64 i915_gem_obj_total_ggtt_size(struct drm_i915_gem_object *obj)
> struct i915_vma *vma;
>
> list_for_each_entry(vma, &obj->vma_list, obj_link) {
> - if (i915_is_ggtt(vma->vm) && drm_mm_node_allocated(&vma->node))
> + if (vma->is_ggtt && drm_mm_node_allocated(&vma->node))
> size += vma->node.size;
> }
>
> @@ -165,12 +165,11 @@ describe_obj(struct seq_file *m, struct drm_i915_gem_object *obj)
> seq_printf(m, " (fence: %d)", obj->fence_reg);
> list_for_each_entry(vma, &obj->vma_list, obj_link) {
> seq_printf(m, " (%sgtt offset: %08llx, size: %08llx",
> - i915_is_ggtt(vma->vm) ? "g" : "pp",
> + vma->is_ggtt ? "g" : "pp",
> vma->node.start, vma->node.size);
> - if (i915_is_ggtt(vma->vm))
> - seq_printf(m, ", type: %u)", vma->ggtt_view.type);
> - else
> - seq_puts(m, ")");
> + if (vma->is_ggtt)
> + seq_printf(m, ", type: %u", vma->ggtt_view.type);
> + seq_puts(m, ")");
> }
> if (obj->stolen)
> seq_printf(m, " (stolen: %08llx)", obj->stolen->start);
> @@ -346,7 +345,7 @@ static int per_file_stats(int id, void *ptr, void *data)
>
> bound++;
>
> - if (i915_is_ggtt(vma->vm)) {
> + if (vma->is_ggtt) {
> stats->global += vma->node.size;
> } else {
> struct i915_hw_ppgtt *ppgtt
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index dbcb7659ba2b..6ce163a681f2 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -2916,18 +2916,11 @@ bool i915_gem_obj_is_pinned(struct drm_i915_gem_object *obj);
> /* Some GGTT VM helpers */
> #define i915_obj_to_ggtt(obj) \
> (&((struct drm_i915_private *)(obj)->base.dev->dev_private)->gtt.base)
> -static inline bool i915_is_ggtt(struct i915_address_space *vm)
> -{
> - struct i915_address_space *ggtt =
> - &((struct drm_i915_private *)(vm)->dev->dev_private)->gtt.base;
> - return vm == ggtt;
> -}
>
> static inline struct i915_hw_ppgtt *
> i915_vm_to_ppgtt(struct i915_address_space *vm)
> {
> WARN_ON(i915_is_ggtt(vm));
> -
> return container_of(vm, struct i915_hw_ppgtt, base);
> }
>
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index e6ace74616b2..144e92df8137 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -2603,8 +2603,7 @@ static int __i915_vma_unbind(struct i915_vma *vma, bool wait)
> return ret;
> }
>
> - if (i915_is_ggtt(vma->vm) &&
> - vma->ggtt_view.type == I915_GGTT_VIEW_NORMAL) {
> + if (vma->is_ggtt && vma->ggtt_view.type == I915_GGTT_VIEW_NORMAL) {
> i915_gem_object_finish_gtt(obj);
>
> /* release the fence reg _after_ flushing */
> @@ -2619,7 +2618,7 @@ static int __i915_vma_unbind(struct i915_vma *vma, bool wait)
> vma->bound = 0;
>
> list_del_init(&vma->vm_link);
> - if (i915_is_ggtt(vma->vm)) {
> + if (vma->is_ggtt) {
> if (vma->ggtt_view.type == I915_GGTT_VIEW_NORMAL) {
> obj->map_and_fenceable = false;
> } else if (vma->ggtt_view.pages) {
> @@ -3889,17 +3888,14 @@ struct i915_vma *i915_gem_obj_to_ggtt_view(struct drm_i915_gem_object *obj,
>
> void i915_gem_vma_destroy(struct i915_vma *vma)
> {
> - struct i915_address_space *vm = NULL;
> WARN_ON(vma->node.allocated);
>
> /* Keep the vma as a placeholder in the execbuffer reservation lists */
> if (!list_empty(&vma->exec_list))
> return;
>
> - vm = vma->vm;
> -
> - if (!i915_is_ggtt(vm))
> - i915_ppgtt_put(i915_vm_to_ppgtt(vm));
> + if (!vma->is_ggtt)
> + i915_ppgtt_put(i915_vm_to_ppgtt(vma->vm));
>
> list_del(&vma->obj_link);
>
> @@ -4425,7 +4421,7 @@ u64 i915_gem_obj_offset(struct drm_i915_gem_object *o,
> WARN_ON(vm == &dev_priv->mm.aliasing_ppgtt->base);
>
> list_for_each_entry(vma, &o->vma_list, obj_link) {
> - if (i915_is_ggtt(vma->vm) &&
> + if (vma->is_ggtt &&
> vma->ggtt_view.type != I915_GGTT_VIEW_NORMAL)
> continue;
> if (vma->vm == vm)
> @@ -4458,7 +4454,7 @@ bool i915_gem_obj_bound(struct drm_i915_gem_object *o,
> struct i915_vma *vma;
>
> list_for_each_entry(vma, &o->vma_list, obj_link) {
> - if (i915_is_ggtt(vma->vm) &&
> + if (vma->is_ggtt &&
> vma->ggtt_view.type != I915_GGTT_VIEW_NORMAL)
> continue;
> if (vma->vm == vm && drm_mm_node_allocated(&vma->node))
> @@ -4505,7 +4501,7 @@ unsigned long i915_gem_obj_size(struct drm_i915_gem_object *o,
> BUG_ON(list_empty(&o->vma_list));
>
> list_for_each_entry(vma, &o->vma_list, obj_link) {
> - if (i915_is_ggtt(vma->vm) &&
> + if (vma->is_ggtt &&
> vma->ggtt_view.type != I915_GGTT_VIEW_NORMAL)
> continue;
> if (vma->vm == vm)
> diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
> index e9741368972e..6788f71ad989 100644
> --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
> +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
> @@ -658,7 +658,7 @@ need_reloc_mappable(struct i915_vma *vma)
> if (entry->relocation_count == 0)
> return false;
>
> - if (!i915_is_ggtt(vma->vm))
> + if (!vma->is_ggtt)
> return false;
>
> /* See also use_cpu_reloc() */
> @@ -677,8 +677,7 @@ eb_vma_misplaced(struct i915_vma *vma)
> struct drm_i915_gem_exec_object2 *entry = vma->exec_entry;
> struct drm_i915_gem_object *obj = vma->obj;
>
> - WARN_ON(entry->flags & __EXEC_OBJECT_NEEDS_MAP &&
> - !i915_is_ggtt(vma->vm));
> + WARN_ON(entry->flags & __EXEC_OBJECT_NEEDS_MAP && !vma->is_ggtt);
>
> if (entry->alignment &&
> vma->node.start & (entry->alignment - 1))
> diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
> index 25bcea3e6ab6..da150c27a76c 100644
> --- a/drivers/gpu/drm/i915/i915_gem_gtt.c
> +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
> @@ -3134,6 +3134,7 @@ int i915_gem_gtt_init(struct drm_device *dev)
> }
>
> gtt->base.dev = dev;
> + gtt->base.is_ggtt = true;
>
> ret = gtt->gtt_probe(dev, &gtt->base.total, &gtt->stolen_size,
> &gtt->mappable_base, &gtt->mappable_end);
> @@ -3242,13 +3243,14 @@ __i915_gem_vma_create(struct drm_i915_gem_object *obj,
> INIT_LIST_HEAD(&vma->exec_list);
> vma->vm = vm;
> vma->obj = obj;
> + vma->is_ggtt = i915_is_ggtt(vm);
>
> if (i915_is_ggtt(vm))
> vma->ggtt_view = *ggtt_view;
> + else
> + i915_ppgtt_get(i915_vm_to_ppgtt(vm));
>
> list_add_tail(&vma->obj_link, &obj->vma_list);
> - if (!i915_is_ggtt(vm))
> - i915_ppgtt_get(i915_vm_to_ppgtt(vm));
>
> return vma;
> }
> @@ -3520,13 +3522,9 @@ int i915_vma_bind(struct i915_vma *vma, enum i915_cache_level cache_level,
> return 0;
>
> if (vma->bound == 0 && vma->vm->allocate_va_range) {
> - trace_i915_va_alloc(vma->vm,
> - vma->node.start,
> - vma->node.size,
> - VM_TO_TRACE_NAME(vma->vm));
> -
> /* XXX: i915_vma_pin() will fix this +- hack */
> vma->pin_count++;
> + trace_i915_va_alloc(vma);
> ret = vma->vm->allocate_va_range(vma->vm,
> vma->node.start,
> vma->node.size);
> diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
> index 2497671d1e1a..bae005a62cfc 100644
> --- a/drivers/gpu/drm/i915/i915_gem_gtt.h
> +++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
> @@ -184,6 +184,7 @@ struct i915_vma {
> #define GLOBAL_BIND (1<<0)
> #define LOCAL_BIND (1<<1)
> unsigned int bound : 4;
> + bool is_ggtt : 1;
>
> /**
> * Support different GGTT views into the same object.
> @@ -276,6 +277,8 @@ struct i915_address_space {
> u64 start; /* Start offset always 0 for dri2 */
> u64 total; /* size addr space maps (ex. 2GB for ggtt) */
>
> + bool is_ggtt;
> +
> struct i915_page_scratch *scratch_page;
> struct i915_page_table *scratch_pt;
> struct i915_page_directory *scratch_pd;
> @@ -331,6 +334,8 @@ struct i915_address_space {
> u32 flags);
> };
>
> +#define i915_is_ggtt(V) ((V)->is_ggtt)
> +
> /* The Graphics Translation Table is the way in which GEN hardware translates a
> * Graphics Virtual Address into a Physical Address. In addition to the normal
> * collateral associated with any va->pa translations GEN hardware also has a
> diff --git a/drivers/gpu/drm/i915/i915_trace.h b/drivers/gpu/drm/i915/i915_trace.h
> index 85469e3c740a..e486dcef508d 100644
> --- a/drivers/gpu/drm/i915/i915_trace.h
> +++ b/drivers/gpu/drm/i915/i915_trace.h
> @@ -175,35 +175,24 @@ TRACE_EVENT(i915_vma_unbind,
> __entry->obj, __entry->offset, __entry->size, __entry->vm)
> );
>
> -#define VM_TO_TRACE_NAME(vm) \
> - (i915_is_ggtt(vm) ? "G" : \
> - "P")
> -
> -DECLARE_EVENT_CLASS(i915_va,
> - TP_PROTO(struct i915_address_space *vm, u64 start, u64 length, const char *name),
> - TP_ARGS(vm, start, length, name),
> +TRACE_EVENT(i915_va_alloc,
> + TP_PROTO(struct i915_vma *vma),
> + TP_ARGS(vma),
>
> TP_STRUCT__entry(
> __field(struct i915_address_space *, vm)
> __field(u64, start)
> __field(u64, end)
> - __string(name, name)
> ),
>
> TP_fast_assign(
> - __entry->vm = vm;
> - __entry->start = start;
> - __entry->end = start + length - 1;
> - __assign_str(name, name);
> + __entry->vm = vma->vm;
> + __entry->start = vma->node.start;
> + __entry->end = vma->node.start + vma->node.size - 1;
> ),
>
> - TP_printk("vm=%p (%s), 0x%llx-0x%llx",
> - __entry->vm, __get_str(name), __entry->start, __entry->end)
> -);
> -
> -DEFINE_EVENT(i915_va, i915_va_alloc,
> - TP_PROTO(struct i915_address_space *vm, u64 start, u64 length, const char *name),
> - TP_ARGS(vm, start, length, name)
> + TP_printk("vm=%p (%c), 0x%llx-0x%llx",
> + __entry->vm, i915_is_ggtt(__entry->vm) ? 'G' : 'P', __entry->start, __entry->end)
> );
>
> DECLARE_EVENT_CLASS(i915_px_entry,