[Intel-xe] [RFC PATCH 1/1] drm/xe: switch to using drm_exec

Matthew Brost matthew.brost at intel.com
Mon Apr 17 00:24:03 UTC 2023


On Fri, Apr 14, 2023 at 12:27:45PM +0200, Francois Dugast wrote:
> Replace the use of ttm_execbuf_util helpers with the new drm_exec
> helpers. They are only used when locking multiple objects.
> 
> Signed-off-by: Francois Dugast <francois.dugast at intel.com>

I have a very similar version but it is based on GPUVA:
https://gitlab.freedesktop.org/drm/xe/kernel/-/merge_requests/339/diffs?commit_id=cccf1dc2227c22dc06045c5ce524e13b517d6874

We can work together on getting a version merged.

> ---
>  drivers/gpu/drm/xe/xe_bo.c           |  22 ++-
>  drivers/gpu/drm/xe/xe_bo_types.h     |   1 -
>  drivers/gpu/drm/xe/xe_exec.c         |  32 ++--
>  drivers/gpu/drm/xe/xe_gt_pagefault.c |  67 +++++----
>  drivers/gpu/drm/xe/xe_vm.c           | 217 +++++++++++----------------
>  drivers/gpu/drm/xe/xe_vm.h           |  19 +--
>  6 files changed, 159 insertions(+), 199 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c
> index 3ab404e33fae..ff707eadb96b 100644
> --- a/drivers/gpu/drm/xe/xe_bo.c
> +++ b/drivers/gpu/drm/xe/xe_bo.c
> @@ -8,6 +8,7 @@
>  #include <linux/dma-buf.h>
>  
>  #include <drm/drm_drv.h>
> +#include <drm/drm_exec.h>
>  #include <drm/drm_gem_ttm_helper.h>
>  #include <drm/ttm/ttm_device.h>
>  #include <drm/ttm/ttm_placement.h>
> @@ -1723,17 +1724,24 @@ int xe_gem_mmap_offset_ioctl(struct drm_device *dev, void *data,
>  int xe_bo_lock(struct xe_bo *bo, struct ww_acquire_ctx *ww,
>  	       int num_resv, bool intr)
>  {
> -	struct ttm_validate_buffer tv_bo;
> -	LIST_HEAD(objs);
> -	LIST_HEAD(dups);
> +	struct dma_resv *obj;
> +	int ret;
>  
>  	XE_BUG_ON(!ww);
>  
> -	tv_bo.num_shared = num_resv;
> -	tv_bo.bo = &bo->ttm;;
> -	list_add_tail(&tv_bo.head, &objs);
> +	obj = bo->ttm.base.resv;
> +	ww_acquire_init(ww, &reservation_ww_class);
> +
> +	if (intr)
> +		ret = dma_resv_lock_interruptible(obj, ww);
> +	else
> +		ret = dma_resv_lock(obj, ww);
> +
> +	if (unlikely(ret))
> +		return ret;
>  
> -	return ttm_eu_reserve_buffers(ww, &objs, intr, &dups);
> +	num_resv = max(num_resv, 1);
> +	return dma_resv_reserve_fences(obj, num_resv);

Why not just use drm_exec here?

>  }
>  
>  void xe_bo_unlock(struct xe_bo *bo, struct ww_acquire_ctx *ww)
> diff --git a/drivers/gpu/drm/xe/xe_bo_types.h b/drivers/gpu/drm/xe/xe_bo_types.h
> index 06de3330211d..2ba34a8c9b66 100644
> --- a/drivers/gpu/drm/xe/xe_bo_types.h
> +++ b/drivers/gpu/drm/xe/xe_bo_types.h
> @@ -11,7 +11,6 @@
>  #include <drm/drm_mm.h>
>  #include <drm/ttm/ttm_bo.h>
>  #include <drm/ttm/ttm_device.h>
> -#include <drm/ttm/ttm_execbuf_util.h>
>  #include <drm/ttm/ttm_placement.h>
>  
>  struct xe_device;
> diff --git a/drivers/gpu/drm/xe/xe_exec.c b/drivers/gpu/drm/xe/xe_exec.c
> index ea869f2452ef..ff41fa828c1c 100644
> --- a/drivers/gpu/drm/xe/xe_exec.c
> +++ b/drivers/gpu/drm/xe/xe_exec.c
> @@ -6,6 +6,7 @@
>  #include "xe_exec.h"
>  
>  #include <drm/drm_device.h>
> +#include <drm/drm_exec.h>
>  #include <drm/drm_file.h>
>  #include <drm/xe_drm.h>
>  
> @@ -91,21 +92,16 @@
>   *	Unlock all
>   */
>  
> -static int xe_exec_begin(struct xe_engine *e, struct ww_acquire_ctx *ww,
> -			 struct ttm_validate_buffer tv_onstack[],
> -			 struct ttm_validate_buffer **tv,
> -			 struct list_head *objs)
> +static int xe_exec_begin(struct xe_engine *e, struct drm_exec *exec)
>  {
>  	struct xe_vm *vm = e->vm;
>  	struct xe_vma *vma;
> -	LIST_HEAD(dups);
>  	int err;
>  
> -	*tv = NULL;
>  	if (xe_vm_no_dma_fences(e->vm))
>  		return 0;
>  
> -	err = xe_vm_lock_dma_resv(vm, ww, tv_onstack, tv, objs, true, 1);
> +	err = xe_vm_lock_dma_resv(vm, exec, 1);
>  	if (err)
>  		return err;
>  
> @@ -120,8 +116,7 @@ static int xe_exec_begin(struct xe_engine *e, struct ww_acquire_ctx *ww,
>  
>  		err = xe_bo_validate(vma->bo, vm, false);
>  		if (err) {
> -			xe_vm_unlock_dma_resv(vm, tv_onstack, *tv, ww, objs);
> -			*tv = NULL;
> +			xe_vm_unlock_dma_resv(vm);
>  			return err;
>  		}
>  	}
> @@ -129,14 +124,10 @@ static int xe_exec_begin(struct xe_engine *e, struct ww_acquire_ctx *ww,
>  	return 0;
>  }
>  
> -static void xe_exec_end(struct xe_engine *e,
> -			struct ttm_validate_buffer *tv_onstack,
> -			struct ttm_validate_buffer *tv,
> -			struct ww_acquire_ctx *ww,
> -			struct list_head *objs)
> +static void xe_exec_end(struct xe_engine *e)
>  {
>  	if (!xe_vm_no_dma_fences(e->vm))
> -		xe_vm_unlock_dma_resv(e->vm, tv_onstack, tv, ww, objs);
> +		xe_vm_unlock_dma_resv(e->vm);
>  }
>  
>  int xe_exec_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
> @@ -149,14 +140,11 @@ int xe_exec_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>  	struct xe_engine *engine;
>  	struct xe_sync_entry *syncs = NULL;
>  	u64 addresses[XE_HW_ENGINE_MAX_INSTANCE];
> -	struct ttm_validate_buffer tv_onstack[XE_ONSTACK_TV];
> -	struct ttm_validate_buffer *tv = NULL;
>  	u32 i, num_syncs = 0;
>  	struct xe_sched_job *job;
>  	struct dma_fence *rebind_fence;
>  	struct xe_vm *vm;
> -	struct ww_acquire_ctx ww;
> -	struct list_head objs;
> +	struct drm_exec exec;
>  	bool write_locked;
>  	int err = 0;
>  
> @@ -267,7 +255,8 @@ int xe_exec_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>  			goto err_unlock_list;
>  	}
>  
> -	err = xe_exec_begin(engine, &ww, tv_onstack, &tv, &objs);
> +	drm_exec_init(&exec, true);
> +	err = xe_exec_begin(engine, &exec);

Move drm_exec_init to xe_exec_begin or xe_vm_lock_dma_resv?

>  	if (err)
>  		goto err_unlock_list;
>  
> @@ -373,8 +362,9 @@ int xe_exec_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>  	if (err)
>  		xe_sched_job_put(job);
>  err_engine_end:
> -	xe_exec_end(engine, tv_onstack, tv, &ww, &objs);
> +	xe_exec_end(engine);
>  err_unlock_list:
> +	drm_exec_fini(&exec);

Move to xe_exec_end / or better yet xe_vm_unlock_dma_resv.

>  	if (write_locked)
>  		up_write(&vm->lock);
>  	else
> diff --git a/drivers/gpu/drm/xe/xe_gt_pagefault.c b/drivers/gpu/drm/xe/xe_gt_pagefault.c
> index 1677640e1075..ffa8119f88c5 100644
> --- a/drivers/gpu/drm/xe/xe_gt_pagefault.c
> +++ b/drivers/gpu/drm/xe/xe_gt_pagefault.c
> @@ -8,8 +8,8 @@
>  #include <linux/bitfield.h>
>  #include <linux/circ_buf.h>
>  
> +#include <drm/drm_exec.h>
>  #include <drm/drm_managed.h>
> -#include <drm/ttm/ttm_execbuf_util.h>
>  
>  #include "xe_bo.h"
>  #include "xe_gt.h"
> @@ -110,10 +110,8 @@ static int handle_pagefault(struct xe_gt *gt, struct pagefault *pf)
>  	struct xe_vm *vm;
>  	struct xe_vma *vma = NULL;
>  	struct xe_bo *bo;
> -	LIST_HEAD(objs);
> -	LIST_HEAD(dups);
> -	struct ttm_validate_buffer tv_bo, tv_vm;
>  	struct ww_acquire_ctx ww;
> +	struct drm_exec exec;
>  	struct dma_fence *fence;
>  	bool write_locked;
>  	int ret = 0;
> @@ -174,19 +172,25 @@ static int handle_pagefault(struct xe_gt *gt, struct pagefault *pf)
>  	if (only_needs_bo_lock(bo)) {
>  		/* This path ensures the BO's LRU is updated */
>  		ret = xe_bo_lock(bo, &ww, xe->info.tile_count, false);
> +		if (ret)
> +			goto unlock_vm;
>  	} else {
> -		tv_vm.num_shared = xe->info.tile_count;
> -		tv_vm.bo = xe_vm_ttm_bo(vm);
> -		list_add(&tv_vm.head, &objs);
> -		if (bo) {
> -			tv_bo.bo = &bo->ttm;
> -			tv_bo.num_shared = xe->info.tile_count;
> -			list_add(&tv_bo.head, &objs);
> +		drm_exec_init(&exec, false);
> +		drm_exec_while_not_all_locked(&exec) {
> +			ret = drm_exec_prepare_obj(&exec, &xe_vm_ttm_bo(vm)->base,
> +						   xe->info.tile_count);
> +			drm_exec_continue_on_contention(&exec);
> +			if (ret)
> +				goto unlock_dma_resv;
> +			if (bo) {
> +				ret = drm_exec_prepare_obj(&exec, &bo->ttm.base,
> +							   xe->info.tile_count);
> +				drm_exec_continue_on_contention(&exec);
> +				if (ret)
> +					goto unlock_dma_resv;
> +			}
>  		}
> -		ret = ttm_eu_reserve_buffers(&ww, &objs, false, &dups);
>  	}
> -	if (ret)
> -		goto unlock_vm;
>  
>  	if (atomic) {
>  		if (xe_vma_is_userptr(vma)) {
> @@ -230,7 +234,7 @@ static int handle_pagefault(struct xe_gt *gt, struct pagefault *pf)
>  	if (only_needs_bo_lock(bo))
>  		xe_bo_unlock(bo, &ww);
>  	else
> -		ttm_eu_backoff_reservation(&ww, &objs);
> +		drm_exec_fini(&exec);
>  unlock_vm:
>  	if (!ret)
>  		vm->usm.last_fault_vma = vma;
> @@ -501,10 +505,8 @@ static int handle_acc(struct xe_gt *gt, struct acc *acc)
>  	struct xe_vm *vm;
>  	struct xe_vma *vma;
>  	struct xe_bo *bo;
> -	LIST_HEAD(objs);
> -	LIST_HEAD(dups);
> -	struct ttm_validate_buffer tv_bo, tv_vm;
>  	struct ww_acquire_ctx ww;
> +	struct drm_exec exec;
>  	int ret = 0;
>  
>  	/* We only support ACC_TRIGGER at the moment */
> @@ -540,25 +542,34 @@ static int handle_acc(struct xe_gt *gt, struct acc *acc)
>  	if (only_needs_bo_lock(bo)) {
>  		/* This path ensures the BO's LRU is updated */
>  		ret = xe_bo_lock(bo, &ww, xe->info.tile_count, false);
> +		if (ret)
> +			goto unlock_vm;
>  	} else {
> -		tv_vm.num_shared = xe->info.tile_count;
> -		tv_vm.bo = xe_vm_ttm_bo(vm);
> -		list_add(&tv_vm.head, &objs);
> -		tv_bo.bo = &bo->ttm;
> -		tv_bo.num_shared = xe->info.tile_count;
> -		list_add(&tv_bo.head, &objs);
> -		ret = ttm_eu_reserve_buffers(&ww, &objs, false, &dups);
> +		drm_exec_init(&exec, false);
> +		drm_exec_while_not_all_locked(&exec) {
> +			ret = drm_exec_prepare_obj(&exec, &xe_vm_ttm_bo(vm)->base,
> +						   xe->info.tile_count);
> +			drm_exec_continue_on_contention(&exec);
> +			if (ret)
> +				goto unlock_dma_resv;
> +			if (bo) {
> +				ret = drm_exec_prepare_obj(&exec, &bo->ttm.base,
> +							   xe->info.tile_count);
> +				drm_exec_continue_on_contention(&exec);
> +				if (ret)
> +					goto unlock_dma_resv;
> +			}
> +		}
>  	}
> -	if (ret)
> -		goto unlock_vm;
>  
>  	/* Migrate to VRAM, move should invalidate the VMA first */
>  	ret = xe_bo_migrate(bo, XE_PL_VRAM0 + gt->info.vram_id);
>  
> +unlock_dma_resv:
>  	if (only_needs_bo_lock(bo))
>  		xe_bo_unlock(bo, &ww);
>  	else
> -		ttm_eu_backoff_reservation(&ww, &objs);
> +		drm_exec_fini(&exec);
>  unlock_vm:
>  	up_read(&vm->lock);
>  	xe_vm_put(vm);
> diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
> index bdf82d34eb66..be6fd30ca1ee 100644
> --- a/drivers/gpu/drm/xe/xe_vm.c
> +++ b/drivers/gpu/drm/xe/xe_vm.c
> @@ -7,7 +7,7 @@
>  
>  #include <linux/dma-fence-array.h>
>  
> -#include <drm/ttm/ttm_execbuf_util.h>
> +#include <drm/drm_exec.h>
>  #include <drm/ttm/ttm_tt.h>
>  #include <drm/xe_drm.h>
>  #include <linux/kthread.h>
> @@ -317,11 +317,8 @@ static void resume_and_reinstall_preempt_fences(struct xe_vm *vm)
>  
>  int xe_vm_add_compute_engine(struct xe_vm *vm, struct xe_engine *e)
>  {
> -	struct ttm_validate_buffer tv_onstack[XE_ONSTACK_TV];
> -	struct ttm_validate_buffer *tv;
> -	struct ww_acquire_ctx ww;
> -	struct list_head objs;
>  	struct dma_fence *pfence;
> +	struct drm_exec exec;
>  	int err;
>  	bool wait;
>  
> @@ -329,7 +326,8 @@ int xe_vm_add_compute_engine(struct xe_vm *vm, struct xe_engine *e)
>  
>  	down_write(&vm->lock);
>  
> -	err = xe_vm_lock_dma_resv(vm, &ww, tv_onstack, &tv, &objs, true, 1);
> +	drm_exec_init(&exec, true);
> +	err = xe_vm_lock_dma_resv(vm, &exec, 1);
>  	if (err)
>  		goto out_unlock_outer;
>  
> @@ -363,8 +361,9 @@ int xe_vm_add_compute_engine(struct xe_vm *vm, struct xe_engine *e)
>  	up_read(&vm->userptr.notifier_lock);
>  
>  out_unlock:
> -	xe_vm_unlock_dma_resv(vm, tv_onstack, tv, &ww, &objs);
> +	xe_vm_unlock_dma_resv(vm);
>  out_unlock_outer:
> +	drm_exec_fini(&exec);
>  	up_write(&vm->lock);
>  
>  	return err;
> @@ -393,68 +392,41 @@ int __xe_vm_userptr_needs_repin(struct xe_vm *vm)
>   * xe_vm_lock_dma_resv() - Lock the vm dma_resv object and the dma_resv
>   * objects of the vm's external buffer objects.
>   * @vm: The vm.
> - * @ww: Pointer to a struct ww_acquire_ctx locking context.
> - * @tv_onstack: Array size XE_ONSTACK_TV of storage for the struct
> - * ttm_validate_buffers used for locking.
> - * @tv: Pointer to a pointer that on output contains the actual storage used.
> - * @objs: List head for the buffer objects locked.
> - * @intr: Whether to lock interruptible.
> + * @exec: Pointer to a struct drm_exec execution context.
>   * @num_shared: Number of dma-fence slots to reserve in the locked objects.
>   *
>   * Locks the vm dma-resv objects and all the dma-resv objects of the
> - * buffer objects on the vm external object list. The TTM utilities require
> - * a list of struct ttm_validate_buffers pointing to the actual buffer
> - * objects to lock. Storage for those struct ttm_validate_buffers should
> - * be provided in @tv_onstack, and is typically reserved on the stack
> - * of the caller. If the size of @tv_onstack isn't sufficient, then
> - * storage will be allocated internally using kvmalloc().
> + * buffer objects on the vm external object list using helpers provided
> + * by drm_exec.
>   *
>   * The function performs deadlock handling internally, and after a
>   * successful return the ww locking transaction should be considered
>   * sealed.
>   *
> - * Return: 0 on success, Negative error code on error. In particular if
> - * @intr is set to true, -EINTR or -ERESTARTSYS may be returned. In case
> - * of error, any locking performed has been reverted.
> + * Return: 0 on success, Negative error code on error.
>   */
> -int xe_vm_lock_dma_resv(struct xe_vm *vm, struct ww_acquire_ctx *ww,
> -			struct ttm_validate_buffer *tv_onstack,
> -			struct ttm_validate_buffer **tv,
> -			struct list_head *objs,
> -			bool intr,
> +int xe_vm_lock_dma_resv(struct xe_vm *vm, struct drm_exec *exec,
>  			unsigned int num_shared)
>  {
> -	struct ttm_validate_buffer *tv_vm, *tv_bo;
>  	struct xe_vma *vma, *next;
> -	LIST_HEAD(dups);
> +	struct drm_gem_object *obj;
>  	int err;
>  
>  	lockdep_assert_held(&vm->lock);
>  
> -	if (vm->extobj.entries < XE_ONSTACK_TV) {
> -		tv_vm = tv_onstack;
> -	} else {
> -		tv_vm = kvmalloc_array(vm->extobj.entries + 1, sizeof(*tv_vm),
> -				       GFP_KERNEL);
> -		if (!tv_vm)
> -			return -ENOMEM;
> +	drm_exec_while_not_all_locked(exec) {
> +		err = drm_exec_prepare_obj(exec, &xe_vm_ttm_bo(vm)->base, num_shared);
> +		drm_exec_break_on_contention(exec);

drm_exec_continue_on_contention

> +		if (unlikely(err) && err != -EALREADY)
> +			goto error;
> +		list_for_each_entry(vma, &vm->extobj.list, extobj.link) {
> +			obj = &vma->bo->ttm.base;
> +			err = drm_exec_prepare_obj(exec, obj, num_shared);
> +			drm_exec_break_on_contention(exec);
> +			if (unlikely(err) && err != -EALREADY)
> +				goto error;
> +		}
>  	}
> -	tv_bo = tv_vm + 1;
> -
> -	INIT_LIST_HEAD(objs);
> -	list_for_each_entry(vma, &vm->extobj.list, extobj.link) {
> -		tv_bo->num_shared = num_shared;
> -		tv_bo->bo = &vma->bo->ttm;
> -
> -		list_add_tail(&tv_bo->head, objs);
> -		tv_bo++;
> -	}
> -	tv_vm->num_shared = num_shared;
> -	tv_vm->bo = xe_vm_ttm_bo(vm);
> -	list_add_tail(&tv_vm->head, objs);
> -	err = ttm_eu_reserve_buffers(ww, objs, intr, &dups);
> -	if (err)
> -		goto out_err;
>  
>  	spin_lock(&vm->notifier.list_lock);
>  	list_for_each_entry_safe(vma, next, &vm->notifier.rebind_list,
> @@ -466,14 +438,9 @@ int xe_vm_lock_dma_resv(struct xe_vm *vm, struct ww_acquire_ctx *ww,
>  			list_move_tail(&vma->rebind_link, &vm->rebind_list);
>  	}
>  	spin_unlock(&vm->notifier.list_lock);
> -
> -	*tv = tv_vm;
>  	return 0;
>  
> -out_err:
> -	if (tv_vm != tv_onstack)
> -		kvfree(tv_vm);
> -
> +error:
>  	return err;
>  }
>  
> @@ -481,19 +448,11 @@ int xe_vm_lock_dma_resv(struct xe_vm *vm, struct ww_acquire_ctx *ww,
>   * xe_vm_unlock_dma_resv() - Unlock reservation objects locked by
>   * xe_vm_lock_dma_resv()
>   * @vm: The vm.
> - * @tv_onstack: The @tv_onstack array given to xe_vm_lock_dma_resv().
> - * @tv: The value of *@tv given by xe_vm_lock_dma_resv().
> - * @ww: The ww_acquire_context used for locking.
> - * @objs: The list returned from xe_vm_lock_dma_resv().
>   *
>   * Unlocks the reservation objects and frees any memory allocated by
>   * xe_vm_lock_dma_resv().
>   */
> -void xe_vm_unlock_dma_resv(struct xe_vm *vm,
> -			   struct ttm_validate_buffer *tv_onstack,
> -			   struct ttm_validate_buffer *tv,
> -			   struct ww_acquire_ctx *ww,
> -			   struct list_head *objs)
> +void xe_vm_unlock_dma_resv(struct xe_vm *vm)
>  {
>  	/*
>  	 * Nothing should've been able to enter the list while we were locked,
> @@ -502,21 +461,14 @@ void xe_vm_unlock_dma_resv(struct xe_vm *vm,
>  	 * addition, and we shouldn't add ourselves.
>  	 */
>  	XE_WARN_ON(!list_empty(&vm->notifier.rebind_list));


Call drm_exec_fini(&exec) here? Also probably need a LRU update for TTM here too.

> -
> -	ttm_eu_backoff_reservation(ww, objs);
> -	if (tv && tv != tv_onstack)
> -		kvfree(tv);
>  }
>  
>  static void preempt_rebind_work_func(struct work_struct *w)
>  {
>  	struct xe_vm *vm = container_of(w, struct xe_vm, preempt.rebind_work);
>  	struct xe_vma *vma;
> -	struct ttm_validate_buffer tv_onstack[XE_ONSTACK_TV];
> -	struct ttm_validate_buffer *tv;
> -	struct ww_acquire_ctx ww;
> -	struct list_head objs;
>  	struct dma_fence *rebind_fence;
> +	struct drm_exec exec;
>  	unsigned int fence_count = 0;
>  	LIST_HEAD(preempt_fences);
>  	int err;
> @@ -556,8 +508,8 @@ static void preempt_rebind_work_func(struct work_struct *w)
>  			goto out_unlock_outer;
>  	}
>  
> -	err = xe_vm_lock_dma_resv(vm, &ww, tv_onstack, &tv, &objs,
> -				  false, vm->preempt.num_engines);
> +	drm_exec_init(&exec, false);
> +	err = xe_vm_lock_dma_resv(vm, &exec, vm->preempt.num_engines);
>  	if (err)
>  		goto out_unlock_outer;
>  
> @@ -631,8 +583,9 @@ static void preempt_rebind_work_func(struct work_struct *w)
>  	up_read(&vm->userptr.notifier_lock);
>  
>  out_unlock:
> -	xe_vm_unlock_dma_resv(vm, tv_onstack, tv, &ww, &objs);
> +	xe_vm_unlock_dma_resv(vm);
>  out_unlock_outer:
> +	drm_exec_fini(&exec);
>  	if (err == -EAGAIN) {
>  		trace_xe_vm_rebind_worker_retry(vm);
>  		goto retry;
> @@ -979,27 +932,28 @@ static void xe_vma_destroy(struct xe_vma *vma, struct dma_fence *fence)
>  
>  static void xe_vma_destroy_unlocked(struct xe_vma *vma)
>  {
> -	struct ttm_validate_buffer tv[2];
> -	struct ww_acquire_ctx ww;
> +	struct drm_exec exec;
> +	struct drm_gem_object *obj;
>  	struct xe_bo *bo = vma->bo;
> -	LIST_HEAD(objs);
> -	LIST_HEAD(dups);
>  	int err;
>  
> -	memset(tv, 0, sizeof(tv));
> -	tv[0].bo = xe_vm_ttm_bo(vma->vm);
> -	list_add(&tv[0].head, &objs);
> -
> -	if (bo) {
> -		tv[1].bo = &xe_bo_get(bo)->ttm;
> -		list_add(&tv[1].head, &objs);
> +	if (bo)
> +		obj = &xe_bo_get(bo)->ttm.base;
> +	drm_exec_init(&exec, false);
> +	drm_exec_while_not_all_locked(&exec) {
> +		err = drm_exec_prepare_obj(&exec, &xe_vm_ttm_bo(vma->vm)->base, 1);
> +		drm_exec_continue_on_contention(&exec);
> +		XE_WARN_ON(err);
> +		if (obj) {
> +			err = drm_exec_prepare_obj(&exec, obj, 1);
> +			drm_exec_continue_on_contention(&exec);
> +			XE_WARN_ON(err);
> +		}

Helper lock function, don't open code these loops.

>  	}
> -	err = ttm_eu_reserve_buffers(&ww, &objs, false, &dups);
> -	XE_WARN_ON(err);
>  
>  	xe_vma_destroy(vma, NULL);
>  
> -	ttm_eu_backoff_reservation(&ww, &objs);
> +	drm_exec_fini(&exec);
>  	if (bo)
>  		xe_bo_put(bo);
>  }
> @@ -2008,12 +1962,6 @@ struct ttm_buffer_object *xe_vm_ttm_bo(struct xe_vm *vm)
>  	return &vm->pt_root[idx]->bo->ttm;
>  }
>  
> -static void xe_vm_tv_populate(struct xe_vm *vm, struct ttm_validate_buffer *tv)
> -{
> -	tv->num_shared = 1;
> -	tv->bo = xe_vm_ttm_bo(vm);
> -}
> -
>  static bool is_map_op(u32 op)
>  {
>  	return VM_BIND_OP(op) == XE_VM_BIND_OP_MAP ||
> @@ -2032,11 +1980,9 @@ static int vm_bind_ioctl(struct xe_vm *vm, struct xe_vma *vma,
>  			 struct xe_sync_entry *syncs, u32 num_syncs,
>  			 struct async_op_fence *afence)
>  {
> -	LIST_HEAD(objs);
> -	LIST_HEAD(dups);
> -	struct ttm_validate_buffer tv_bo, tv_vm;
> -	struct ww_acquire_ctx ww;
>  	struct xe_bo *vbo;
> +	struct drm_exec exec;
> +	struct ttm_buffer_object *obj;
>  	int err, i;
>  
>  	lockdep_assert_held(&vm->lock);
> @@ -2053,8 +1999,6 @@ static int vm_bind_ioctl(struct xe_vm *vm, struct xe_vma *vma,
>  		return 0;
>  	}
>  
> -	xe_vm_tv_populate(vm, &tv_vm);
> -	list_add_tail(&tv_vm.head, &objs);
>  	vbo = vma->bo;
>  	if (vbo) {
>  		/*
> @@ -2063,29 +2007,41 @@ static int vm_bind_ioctl(struct xe_vm *vm, struct xe_vma *vma,
>  		 * take a reference here.
>  		 */
>  		xe_bo_get(vbo);
> -
> -		tv_bo.bo = &vbo->ttm;
> -		tv_bo.num_shared = 1;
> -		list_add(&tv_bo.head, &objs);
>  	}
> +	obj = xe_vm_ttm_bo(vm);
>  
>  again:
> -	err = ttm_eu_reserve_buffers(&ww, &objs, true, &dups);
> -	if (!err) {
> -		err = __vm_bind_ioctl(vm, vma, e, bo,
> -				      bind_op->op, bind_op->region, syncs,
> -				      num_syncs, afence);
> -		ttm_eu_backoff_reservation(&ww, &objs);
> -		if (err == -EAGAIN && xe_vma_is_userptr(vma)) {
> -			lockdep_assert_held_write(&vm->lock);
> -			err = xe_vma_userptr_pin_pages(vma);
> -			if (!err)
> -				goto again;
> -		}
> +	drm_exec_init(&exec, true);
> +	drm_exec_while_not_all_locked(&exec) {
> +		if (vbo) {
> +			err = drm_exec_prepare_obj(&exec, &vbo->ttm.base, 1);
> +			drm_exec_continue_on_contention(&exec);
> +			if (unlikely(err))
> +				goto error;
> +		}
> +		err = drm_exec_prepare_obj(&exec, &obj->base, 1);
> +		drm_exec_break_on_contention(&exec);
> +		if (err && err != -EALREADY)
> +			goto error;
> +	}
> +	err = __vm_bind_ioctl(vm, vma, e, bo,
> +			      bind_op->op, bind_op->region, syncs,
> +			      num_syncs, afence);
> +	drm_exec_fini(&exec);

Same here, don't open code this.

Matt

> +	if (err == -EAGAIN && xe_vma_is_userptr(vma)) {
> +		lockdep_assert_held_write(&vm->lock);
> +		err = xe_vma_userptr_pin_pages(vma);
> +		if (!err)
> +			goto again;
>  	}
>  	xe_bo_put(vbo);
>  
>  	return err;
> +
> +error:
> +	drm_exec_fini(&exec);
> +	xe_bo_put(vbo);
> +	return err;
>  }
>  
>  struct async_op {
> @@ -3291,17 +3247,24 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>  int xe_vm_lock(struct xe_vm *vm, struct ww_acquire_ctx *ww,
>  	       int num_resv, bool intr)
>  {
> -	struct ttm_validate_buffer tv_vm;
> -	LIST_HEAD(objs);
> -	LIST_HEAD(dups);
> +	struct dma_resv *obj;
> +	int ret;
>  
>  	XE_BUG_ON(!ww);
>  
> -	tv_vm.num_shared = num_resv;
> -	tv_vm.bo = xe_vm_ttm_bo(vm);;
> -	list_add_tail(&tv_vm.head, &objs);
> +	obj = xe_vm_ttm_bo(vm)->base.resv;
> +	ww_acquire_init(ww, &reservation_ww_class);
> +
> +	if (intr)
> +		ret = dma_resv_lock_interruptible(obj, ww);
> +	else
> +		ret = dma_resv_lock(obj, ww);
> +
> +	if (unlikely(ret))
> +		return ret;
>  
> -	return ttm_eu_reserve_buffers(ww, &objs, intr, &dups);
> +	num_resv = max(num_resv, 1);
> +	return dma_resv_reserve_fences(obj, num_resv);
>  }
>  
>  void xe_vm_unlock(struct xe_vm *vm, struct ww_acquire_ctx *ww)
> diff --git a/drivers/gpu/drm/xe/xe_vm.h b/drivers/gpu/drm/xe/xe_vm.h
> index 748dc16ebed9..3fdcef3793e5 100644
> --- a/drivers/gpu/drm/xe/xe_vm.h
> +++ b/drivers/gpu/drm/xe/xe_vm.h
> @@ -6,6 +6,8 @@
>  #ifndef _XE_VM_H_
>  #define _XE_VM_H_
>  
> +#include <drm/drm_exec.h>
> +
>  #include "xe_macros.h"
>  #include "xe_map.h"
>  #include "xe_vm_types.h"
> @@ -124,23 +126,10 @@ int xe_vma_userptr_pin_pages(struct xe_vma *vma);
>  
>  int xe_vma_userptr_check_repin(struct xe_vma *vma);
>  
> -/*
> - * XE_ONSTACK_TV is used to size the tv_onstack array that is input
> - * to xe_vm_lock_dma_resv() and xe_vm_unlock_dma_resv().
> - */
> -#define XE_ONSTACK_TV 20
> -int xe_vm_lock_dma_resv(struct xe_vm *vm, struct ww_acquire_ctx *ww,
> -			struct ttm_validate_buffer *tv_onstack,
> -			struct ttm_validate_buffer **tv,
> -			struct list_head *objs,
> -			bool intr,
> +int xe_vm_lock_dma_resv(struct xe_vm *vm, struct drm_exec *exec,
>  			unsigned int num_shared);
>  
> -void xe_vm_unlock_dma_resv(struct xe_vm *vm,
> -			   struct ttm_validate_buffer *tv_onstack,
> -			   struct ttm_validate_buffer *tv,
> -			   struct ww_acquire_ctx *ww,
> -			   struct list_head *objs);
> +void xe_vm_unlock_dma_resv(struct xe_vm *vm);
>  
>  void xe_vm_fence_all_extobjs(struct xe_vm *vm, struct dma_fence *fence,
>  			     enum dma_resv_usage usage);
> -- 
> 2.25.1
> 


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