On 11/29/2012 12:36 PM, Maarten Lankhorst wrote:
By removing the unlocking of lru and retaking it immediately, a race is removed where the bo is taken off the swap list or the lru list between the unlock and relock. As such the cleanup_refs code can be simplified, it will attempt to call ttm_bo_wait non-blockingly, and if it fails it will drop the locks and perform a blocking wait, or return an error if no_wait_gpu was set.
The need for looping is also eliminated, since swapout and evict_mem_first will always follow the destruction path, no new fence is allowed to be attached. As far as I can see this may already have been the case, but the unlocking / relocking required a complicated loop to deal with re-reservation.
Changes since v1:
- Simplify no_wait_gpu case by folding it in with empty ddestroy.
- Hold a reservation while calling ttm_bo_cleanup_memtype_use again.
Changes since v2:
- Do not remove bo from lru list while waiting
Signed-off-by: Maarten Lankhorst maarten.lankhorst@canonical.com
Reviewed-by: Thomas Hellstrom thellstrom@vmware.com