On Thu, 5 Oct 2017 09:48:24 +0100 Eric Engestrom eric.engestrom@imgtec.com wrote:
On Wednesday, 2017-10-04 22:28:54 +0000, Eric Anholt wrote:
Boris Brezillon boris.brezillon@free-electrons.com writes:
drm_gem_cma_create() prints an error message when dma_alloc_wc() fails to allocate the amount of memory we requested. This can lead to annoying error messages when CMA is only one possible source of memory for the BO allocation.
Turn this error message into a debug one and add a __must_check specifier to make sure all callers are checking the return value.
Signed-off-by: Boris Brezillon boris.brezillon@free-electrons.com
The __must_check seems unnecessary to me -- you're definitely going to be doing something with the return value, because otherwise why did you call the object allocate function?
Indeed, `__must_check` (aka `warn_unused_result`) only makes sure the return value is not discarded, which will probably always be true here.
I agree, this __must_check is not really useful here.
The `warn_unused_result` attribute causes a warning to be emitted if a caller of the function with this attribute does not use its return value.
I think we need a sparse attribute to check that the return value is IS_ERR()-checked?
Can we just turn the dev_err() into dev_dbg() for now? The 'force callers to check IS_ERR()' is kind of orthogonal to the change I'm doing here.
(not volunteering, I have no idea how to add a sparse attribute :)