Re: [PATCH 2/2] drm/xe/pm: skip BO eviction on iGPU for non-hibernation sleep

["Thomas Hellström" <thomas.hellstrom@linux.intel.com>]

On Fri, 2026-11-06 at 10:16 +0000, Matthew Auld wrote:
> On iGPU platforms, system RAM and graphics stolen memory remain
> powered
> during S2idle and S3 (< S4) suspend, so evicting user buffers or
> preparing pinned BOs is unnecessary and needlessly purges DONTNEED
> buffers in userspace caches.
> 
> Distinguish S4 hibernation (.freeze and PM_HIBERNATION_PREPARE) from
> < S4 suspend (.suspend and PM_SUSPEND_PREPARE), and skip BO eviction
> on
> iGPU when not creating a hibernation image.
> 
> Signed-off-by: Matthew Auld <matthew.auld@intel.com>
> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
> Cc: Matthew Brost <matthew.brost@intel.com>
> Cc: Carlos Santa <carlos.santa@intel.com>

Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>



> ---
>  drivers/gpu/drm/xe/xe_pci.c | 21 ++++++++++++++++++---
>  drivers/gpu/drm/xe/xe_pm.c  | 26 ++++++++++++++++++++------
>  drivers/gpu/drm/xe/xe_pm.h  |  2 +-
>  3 files changed, 39 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_pci.c
> b/drivers/gpu/drm/xe/xe_pci.c
> index ba23ec60477b..67be6e707361 100644
> --- a/drivers/gpu/drm/xe/xe_pci.c
> +++ b/drivers/gpu/drm/xe/xe_pci.c
> @@ -1335,7 +1335,7 @@ static void d3cold_toggle(struct pci_dev *pdev,
> enum toggle_d3cold toggle)
>  	}
>  }
>  
> -static int xe_pci_suspend(struct device *dev)
> +static int __xe_pci_suspend(struct device *dev, bool hibernate)
>  {
>  	struct pci_dev *pdev = to_pci_dev(dev);
>  	struct xe_device *xe = pdev_to_xe_device(pdev);
> @@ -1344,7 +1344,7 @@ static int xe_pci_suspend(struct device *dev)
>  	if (xe_survivability_mode_is_boot_enabled(xe))
>  		return -EBUSY;
>  
> -	err = xe_pm_suspend(xe);
> +	err = xe_pm_suspend(xe, hibernate);
>  	if (err)
>  		return err;
>  
> @@ -1362,6 +1362,16 @@ static int xe_pci_suspend(struct device *dev)
>  	return 0;
>  }
>  
> +static int xe_pci_suspend(struct device *dev)
> +{
> +	return __xe_pci_suspend(dev, false);
> +}
> +
> +static int xe_pci_freeze(struct device *dev)
> +{
> +	return __xe_pci_suspend(dev, true);
> +}
> +
>  static int xe_pci_resume(struct device *dev)
>  {
>  	struct pci_dev *pdev = to_pci_dev(dev);
> @@ -1491,7 +1501,12 @@ static int xe_pci_runtime_idle(struct device
> *dev)
>  }
>  
>  static const struct dev_pm_ops xe_pm_ops = {
> -	SET_SYSTEM_SLEEP_PM_OPS(xe_pci_suspend, xe_pci_resume)
> +	.suspend = pm_sleep_ptr(xe_pci_suspend),
> +	.resume = pm_sleep_ptr(xe_pci_resume),
> +	.freeze = pm_sleep_ptr(xe_pci_freeze),
> +	.thaw = pm_sleep_ptr(xe_pci_resume),
> +	.poweroff = pm_sleep_ptr(xe_pci_suspend),
> +	.restore = pm_sleep_ptr(xe_pci_resume),
>  	SET_RUNTIME_PM_OPS(xe_pci_runtime_suspend,
> xe_pci_runtime_resume, xe_pci_runtime_idle)
>  };
>  #endif
> diff --git a/drivers/gpu/drm/xe/xe_pm.c b/drivers/gpu/drm/xe/xe_pm.c
> index 61d68c09189f..e73192b03074 100644
> --- a/drivers/gpu/drm/xe/xe_pm.c
> +++ b/drivers/gpu/drm/xe/xe_pm.c
> @@ -166,13 +166,19 @@ static void xe_rpm_lockmap_release(const struct
> xe_device *xe)
>  			 &xe_pm_runtime_d3cold_map);
>  }
>  
> +static bool xe_pm_needs_bo_evict(struct xe_device *xe, bool
> hibernate)
> +{
> +	return IS_DGFX(xe) || hibernate;
> +}
> +
>  /**
> - * xe_pm_suspend - Helper for System suspend, i.e. S0->S3 / S0-
> >S2idle
> + * xe_pm_suspend - Helper for System suspend, i.e. S0->S3 / S0-
> >S2idle / S0->S4
>   * @xe: xe device instance
> + * @hibernate: true if preparing for S4 hibernation, false for < S4
> suspend
>   *
>   * Return: 0 on success
>   */
> -int xe_pm_suspend(struct xe_device *xe)
> +int xe_pm_suspend(struct xe_device *xe, bool hibernate)
>  {
>  	struct xe_gt *gt;
>  	u8 id;
> @@ -193,10 +199,12 @@ int xe_pm_suspend(struct xe_device *xe)
>  
>  	xe_display_pm_suspend(xe);
>  
> -	/* FIXME: Super racey... */
> -	err = xe_bo_evict_all(xe);
> -	if (err)
> -		goto err_display;
> +	if (xe_pm_needs_bo_evict(xe, hibernate)) {
> +		/* FIXME: Super racey... */
> +		err = xe_bo_evict_all(xe);
> +		if (err)
> +			goto err_display;
> +	}
>  
>  	for_each_gt(gt, xe, id) {
>  		err = xe_gt_suspend(gt);
> @@ -461,6 +469,9 @@ static int xe_pm_notifier_callback(struct
> notifier_block *nb,
>  		struct xe_validation_ctx ctx;
>  
>  		reinit_completion(&xe->pm_block);
> +		if (!xe_pm_needs_bo_evict(xe, action ==
> PM_HIBERNATION_PREPARE))
> +			break;
> +
>  		xe_pm_block_begin_signalling();
>  		xe_pm_runtime_get(xe);
>  		(void)xe_validation_ctx_init(&ctx, &xe->val, NULL,
> @@ -485,6 +496,9 @@ static int xe_pm_notifier_callback(struct
> notifier_block *nb,
>  	case PM_POST_SUSPEND:
>  		complete_all(&xe->pm_block);
>  		xe_pm_wake_rebind_workers(xe);
> +		if (!xe_pm_needs_bo_evict(xe, action ==
> PM_POST_HIBERNATION))
> +			break;
> +
>  		xe_bo_notifier_unprepare_all_pinned(xe);
>  		xe_pm_runtime_put(xe);
>  		break;
> diff --git a/drivers/gpu/drm/xe/xe_pm.h b/drivers/gpu/drm/xe/xe_pm.h
> index 16d4e6c629f1..af81f2a2975f 100644
> --- a/drivers/gpu/drm/xe/xe_pm.h
> +++ b/drivers/gpu/drm/xe/xe_pm.h
> @@ -13,7 +13,7 @@
>  
>  struct xe_device;
>  
> -int xe_pm_suspend(struct xe_device *xe);
> +int xe_pm_suspend(struct xe_device *xe, bool hibernate);
>  int xe_pm_resume(struct xe_device *xe);
>  
>  int xe_pm_init_early(struct xe_device *xe);