On Sun, 27 Nov 2022 14:41:14 +0000 Jonathan Cameron <jic23@xxxxxxxxxx> wrote: > From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> > > The use of ____cacheline_aligned to ensure a buffer is DMA safe only > enforces the start of the buffer alignment. In this case, sufficient > alignment is already ensured by the use of kzalloc(). > ____cacheline_aligned does not ensure that no other members of the > structure are placed in the same cacheline after the end of the > buffer marked. Thus to ensure a DMA safe buffer it must be at the end > of the structure. This move is unnecessary, because the cacheline is 16 bytes and the buffer is 64 bytes. > Whilst here switch from ____cacheline_aligned to > __aligned(ARCH_KMALLOC_MINALIGN) as on some architectures, with variable > sized cacheline lines across their cache hierarchy, require this > greater alignment guarantee for DMA safety. Make this change throughout > the driver as it reduces need for a reader to know about the particular > architecture. This change looks ok. - Lauri
