diff options
author | Thomas Hellstrom <thellstrom@vmware.com> | 2013-10-09 03:18:07 -0700 |
---|---|---|
committer | Thomas Hellstrom <thellstrom@vmware.com> | 2013-11-06 04:14:43 -0800 |
commit | cbe12e74ee4e29b6cb4e63fa284e80b73ad57926 (patch) | |
tree | ef667b3eca6206be60d338af822ab707365d1f74 /drivers/gpu/drm/ttm | |
parent | 4695b03970df378dcb93fe3e7158381f1e980fa2 (diff) | |
download | op-kernel-dev-cbe12e74ee4e29b6cb4e63fa284e80b73ad57926.zip op-kernel-dev-cbe12e74ee4e29b6cb4e63fa284e80b73ad57926.tar.gz |
drm/ttm: Allow vm fault retries
Make use of the FAULT_FLAG_ALLOW_RETRY flag to allow dropping the
mmap_sem while waiting for bo idle.
FAULT_FLAG_ALLOW_RETRY appears to be primarily designed for disk waits
but should work just as fine for GPU waits..
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
Diffstat (limited to 'drivers/gpu/drm/ttm')
-rw-r--r-- | drivers/gpu/drm/ttm/ttm_bo_vm.c | 62 |
1 files changed, 50 insertions, 12 deletions
diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c index 1006c15..c03514b 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c @@ -41,6 +41,51 @@ #define TTM_BO_VM_NUM_PREFAULT 16 +static int ttm_bo_vm_fault_idle(struct ttm_buffer_object *bo, + struct vm_area_struct *vma, + struct vm_fault *vmf) +{ + struct ttm_bo_device *bdev = bo->bdev; + int ret = 0; + + spin_lock(&bdev->fence_lock); + if (likely(!test_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags))) + goto out_unlock; + + /* + * Quick non-stalling check for idle. + */ + ret = ttm_bo_wait(bo, false, false, true); + if (likely(ret == 0)) + goto out_unlock; + + /* + * If possible, avoid waiting for GPU with mmap_sem + * held. + */ + if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) { + ret = VM_FAULT_RETRY; + if (vmf->flags & FAULT_FLAG_RETRY_NOWAIT) + goto out_unlock; + + up_read(&vma->vm_mm->mmap_sem); + (void) ttm_bo_wait(bo, false, true, false); + goto out_unlock; + } + + /* + * Ordinary wait. + */ + ret = ttm_bo_wait(bo, false, true, false); + if (unlikely(ret != 0)) + ret = (ret != -ERESTARTSYS) ? VM_FAULT_SIGBUS : + VM_FAULT_NOPAGE; + +out_unlock: + spin_unlock(&bdev->fence_lock); + return ret; +} + static int ttm_bo_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf) { struct ttm_buffer_object *bo = (struct ttm_buffer_object *) @@ -91,18 +136,11 @@ static int ttm_bo_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf) * Wait for buffer data in transit, due to a pipelined * move. */ - - spin_lock(&bdev->fence_lock); - if (test_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags)) { - ret = ttm_bo_wait(bo, false, true, false); - spin_unlock(&bdev->fence_lock); - if (unlikely(ret != 0)) { - retval = (ret != -ERESTARTSYS) ? - VM_FAULT_SIGBUS : VM_FAULT_NOPAGE; - goto out_unlock; - } - } else - spin_unlock(&bdev->fence_lock); + ret = ttm_bo_vm_fault_idle(bo, vma, vmf); + if (unlikely(ret != 0)) { + retval = ret; + goto out_unlock; + } ret = ttm_mem_io_lock(man, true); if (unlikely(ret != 0)) { |