iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

drm/i915: Untangle the vma pages_mutex

Browse Source 
Any sleeping dma_resv lock taken while the vma pages_mutex is held
will cause a lockdep splat.
Move the i915_gem_object_pin_pages() call out of the pages_mutex
critical section.

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210601074654.3103-2-thomas.hellstrom@linux.intel.com
This commit is contained in:
Thomas Hellström 2021-06-01 09:46:40 +02:00 committed by Matthew Auld
parent 5b26d57fdb
commit 0f4308d524
1 changed files with 17 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
drivers/gpu/drm/i915/i915_vma.c
View File

@ -800,32 +800,37 @@ unpinned:
static int vma_get_pages(struct i915_vma *vma)
{
int err = 0;
bool pinned_pages = false;
if (atomic_add_unless(&vma->pages_count, 1, 0))
return 0;
if (vma->obj) {
err = i915_gem_object_pin_pages(vma->obj);
if (err)
return err;
pinned_pages = true;
}
/* Allocations ahoy! */
if (mutex_lock_interruptible(&vma->pages_mutex))
return -EINTR;
if (mutex_lock_interruptible(&vma->pages_mutex)) {
err = -EINTR;
goto unpin;
}
if (!atomic_read(&vma->pages_count)) {
if (vma->obj) {
err = i915_gem_object_pin_pages(vma->obj);
if (err)
goto unlock;
}
err = vma->ops->set_pages(vma);
if (err) {
if (vma->obj)
i915_gem_object_unpin_pages(vma->obj);
if (err)
goto unlock;
}
pinned_pages = false;
}
atomic_inc(&vma->pages_count);
unlock:
mutex_unlock(&vma->pages_mutex);
unpin:
if (pinned_pages)
__i915_gem_object_unpin_pages(vma->obj);
return err;
}