From: Thomas Hellstrom Date: Wed, 12 Aug 2015 05:31:17 +0000 (-0700) Subject: drm/vmwgfx: Fix execbuf locking issues X-Git-Tag: v4.2-rc7~12^2~1 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=3e04e2fe6d87807d27521ad6ebb9e7919d628f25;p=profile%2Fcommon%2Fplatform%2Fkernel%2Flinux-artik7.git drm/vmwgfx: Fix execbuf locking issues This addresses two issues that cause problems with viewperf maya-03 in situation with memory pressure. The first issue causes attempts to unreserve buffers if batched reservation fails due to, for example, a signal pending. While previously the ttm_eu api was resistant against this type of error, it is no longer and the lockdep code will complain about attempting to unreserve buffers that are not reserved. The issue is resolved by avoid calling ttm_eu_backoff_reservation in the buffer reserve error path. The second issue is that the binding_mutex may be held when user-space fence objects are created and hence during memory reclaims. This may cause recursive attempts to grab the binding mutex. The issue is resolved by not holding the binding mutex across fence creation and submission. Signed-off-by: Thomas Hellstrom Reviewed-by: Sinclair Yeh Cc: Signed-off-by: Dave Airlie --- diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c index 654c8da..97ad3bc 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c @@ -2492,7 +2492,7 @@ int vmw_execbuf_process(struct drm_file *file_priv, ret = ttm_eu_reserve_buffers(&ticket, &sw_context->validate_nodes, true, NULL); if (unlikely(ret != 0)) - goto out_err; + goto out_err_nores; ret = vmw_validate_buffers(dev_priv, sw_context); if (unlikely(ret != 0)) @@ -2536,6 +2536,7 @@ int vmw_execbuf_process(struct drm_file *file_priv, vmw_resource_relocations_free(&sw_context->res_relocations); vmw_fifo_commit(dev_priv, command_size); + mutex_unlock(&dev_priv->binding_mutex); vmw_query_bo_switch_commit(dev_priv, sw_context); ret = vmw_execbuf_fence_commands(file_priv, dev_priv, @@ -2551,7 +2552,6 @@ int vmw_execbuf_process(struct drm_file *file_priv, DRM_ERROR("Fence submission error. Syncing.\n"); vmw_resource_list_unreserve(&sw_context->resource_list, false); - mutex_unlock(&dev_priv->binding_mutex); ttm_eu_fence_buffer_objects(&ticket, &sw_context->validate_nodes, (void *) fence);