From c2ea703dcafccf18d7d77d8b68fb08c2d9842b7a Mon Sep 17 00:00:00 2001 From: Thomas Hellström Date: Tue, 21 Dec 2021 21:00:50 +0100 Subject: drm/i915: Require the vm mutex for i915_vma_bind() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Protect updates of struct i915_vma flags and async binding / unbinding with the vm::mutex. This means that i915_vma_bind() needs to assert vm::mutex held. In order to make that possible drop the caching of kmap_atomic() maps around i915_vma_bind(). An alternative would be to use kmap_local() but since we block cpu unplugging during sleeps inside kmap_local() sections this may have unwanted side-effects. Particularly since we might wait for gpu while holding the vm mutex. This change may theoretically increase execbuf cpu-usage on snb, but at least on non-highmem systems that increase should be very small. Signed-off-by: Thomas Hellström Reviewed-by: Matthew Auld Link: https://patchwork.freedesktop.org/patch/msgid/20211221200050.436316-5-thomas.hellstrom@linux.intel.com --- drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c | 50 +++++++++++++++++++++++++- drivers/gpu/drm/i915/i915_vma.c | 1 + 2 files changed, 50 insertions(+), 1 deletion(-) (limited to 'drivers/gpu/drm/i915') diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c index 1f025a27c649..e7f548a22970 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c @@ -1098,6 +1098,47 @@ static inline struct i915_ggtt *cache_to_ggtt(struct reloc_cache *cache) return &i915->ggtt; } +static void reloc_cache_unmap(struct reloc_cache *cache) +{ + void *vaddr; + + if (!cache->vaddr) + return; + + vaddr = unmask_page(cache->vaddr); + if (cache->vaddr & KMAP) + kunmap_atomic(vaddr); + else + io_mapping_unmap_atomic((void __iomem *)vaddr); +} + +static void reloc_cache_remap(struct reloc_cache *cache, + struct drm_i915_gem_object *obj) +{ + void *vaddr; + + if (!cache->vaddr) + return; + + if (cache->vaddr & KMAP) { + struct page *page = i915_gem_object_get_page(obj, cache->page); + + vaddr = kmap_atomic(page); + cache->vaddr = unmask_flags(cache->vaddr) | + (unsigned long)vaddr; + } else { + struct i915_ggtt *ggtt = cache_to_ggtt(cache); + unsigned long offset; + + offset = cache->node.start; + if (!drm_mm_node_allocated(&cache->node)) + offset += cache->page << PAGE_SHIFT; + + cache->vaddr = (unsigned long) + io_mapping_map_atomic_wc(&ggtt->iomap, offset); + } +} + static void reloc_cache_reset(struct reloc_cache *cache, struct i915_execbuffer *eb) { void *vaddr; @@ -1362,10 +1403,17 @@ eb_relocate_entry(struct i915_execbuffer *eb, * batchbuffers. */ if (reloc->write_domain == I915_GEM_DOMAIN_INSTRUCTION && - GRAPHICS_VER(eb->i915) == 6) { + GRAPHICS_VER(eb->i915) == 6 && + !i915_vma_is_bound(target->vma, I915_VMA_GLOBAL_BIND)) { + struct i915_vma *vma = target->vma; + + reloc_cache_unmap(&eb->reloc_cache); + mutex_lock(&vma->vm->mutex); err = i915_vma_bind(target->vma, target->vma->obj->cache_level, PIN_GLOBAL, NULL); + mutex_unlock(&vma->vm->mutex); + reloc_cache_remap(&eb->reloc_cache, ev->vma->obj); if (err) return err; } diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c index 3ff95e54a353..29a858c53bdd 100644 --- a/drivers/gpu/drm/i915/i915_vma.c +++ b/drivers/gpu/drm/i915/i915_vma.c @@ -393,6 +393,7 @@ int i915_vma_bind(struct i915_vma *vma, u32 bind_flags; u32 vma_flags; + lockdep_assert_held(&vma->vm->mutex); GEM_BUG_ON(!drm_mm_node_allocated(&vma->node)); GEM_BUG_ON(vma->size > vma->node.size); -- cgit v1.2.3-59-g8ed1b