The patch below does not apply to the 5.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 420a07b841d03f6a436d8c06571c69aa5c783897 Mon Sep 17 00:00:00 2001 From: Nirmoy Das nirmoy.das@intel.com Date: Wed, 25 May 2022 11:59:55 +0200 Subject: [PATCH] drm/i915: Individualize fences before adding to dma_resv obj
_i915_vma_move_to_active() can receive > 1 fences for multiple batch buffers submission. Because dma_resv_add_fence() can only accept one fence at a time, change _i915_vma_move_to_active() to be aware of multiple fences so that it can add individual fences to the dma resv object.
v6: fix multi-line comment. v5: remove double fence reservation for batch VMAs. v4: Reserve fences for composite_fence on multi-batch contexts and also reserve fence slots to composite_fence for each VMAs. v3: dma_resv_reserve_fences is not cumulative so pass num_fences. v2: make sure to reserve enough fence slots before adding.
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/5614 Fixes: 544460c33821 ("drm/i915: Multi-BB execbuf") Cc: stable@vger.kernel.org # v5.16+ Signed-off-by: Nirmoy Das nirmoy.das@intel.com Reviewed-by: Matthew Auld matthew.auld@intel.com Reviewed-by: Andrzej Hajda andrzej.hajda@intel.com Signed-off-by: Matthew Auld matthew.auld@intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20220525095955.15371-1-nirmoy....
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c index c326bd2b444f..30fe847c6664 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c @@ -999,7 +999,8 @@ static int eb_validate_vmas(struct i915_execbuffer *eb) } }
- err = dma_resv_reserve_fences(vma->obj->base.resv, 1); + /* Reserve enough slots to accommodate composite fences */ + err = dma_resv_reserve_fences(vma->obj->base.resv, eb->num_batches); if (err) return err;
diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c index 4f6db539571a..0bffb70b3c5f 100644 --- a/drivers/gpu/drm/i915/i915_vma.c +++ b/drivers/gpu/drm/i915/i915_vma.c @@ -23,6 +23,7 @@ */
#include <linux/sched/mm.h> +#include <linux/dma-fence-array.h> #include <drm/drm_gem.h>
#include "display/intel_frontbuffer.h" @@ -1823,6 +1824,21 @@ int _i915_vma_move_to_active(struct i915_vma *vma, if (unlikely(err)) return err;
+ /* + * Reserve fences slot early to prevent an allocation after preparing + * the workload and associating fences with dma_resv. + */ + if (fence && !(flags & __EXEC_OBJECT_NO_RESERVE)) { + struct dma_fence *curr; + int idx; + + dma_fence_array_for_each(curr, idx, fence) + ; + err = dma_resv_reserve_fences(vma->obj->base.resv, idx); + if (unlikely(err)) + return err; + } + if (flags & EXEC_OBJECT_WRITE) { struct intel_frontbuffer *front;
@@ -1832,31 +1848,23 @@ int _i915_vma_move_to_active(struct i915_vma *vma, i915_active_add_request(&front->write, rq); intel_frontbuffer_put(front); } + }
- if (!(flags & __EXEC_OBJECT_NO_RESERVE)) { - err = dma_resv_reserve_fences(vma->obj->base.resv, 1); - if (unlikely(err)) - return err; - } + if (fence) { + struct dma_fence *curr; + enum dma_resv_usage usage; + int idx;
- if (fence) { - dma_resv_add_fence(vma->obj->base.resv, fence, - DMA_RESV_USAGE_WRITE); + obj->read_domains = 0; + if (flags & EXEC_OBJECT_WRITE) { + usage = DMA_RESV_USAGE_WRITE; obj->write_domain = I915_GEM_DOMAIN_RENDER; - obj->read_domains = 0; - } - } else { - if (!(flags & __EXEC_OBJECT_NO_RESERVE)) { - err = dma_resv_reserve_fences(vma->obj->base.resv, 1); - if (unlikely(err)) - return err; + } else { + usage = DMA_RESV_USAGE_READ; }
- if (fence) { - dma_resv_add_fence(vma->obj->base.resv, fence, - DMA_RESV_USAGE_READ); - obj->write_domain = 0; - } + dma_fence_array_for_each(curr, idx, fence) + dma_resv_add_fence(vma->obj->base.resv, curr, usage); }
if (flags & EXEC_OBJECT_NEEDS_FENCE && vma->fence)