Hi Arnd, On Mon, Sep 20, 2021 at 02:50:52PM +0200, Arnd Bergmann wrote: > On Mon, Sep 20, 2021 at 2:47 PM Laurent Pinchart wrote: > > > > It's only a few bytes of data in struct dma_device, but a bit more in > > .text here. Is the simplification really required in this driver ? > > The intention was to not change the resulting object code in this driver, > and I still don't see where it would grow after dead-code-elimination removes > all the unused static functions. What am I missing? Indeed, gcc does a fairly good job there. The .text section doesn't grow. Interestingly, there's an increase in size in the .data and .rodata sections in the xilinx-dpdma module: - 8 .rodata.str1.8 0000029f 0000000000000000 0000000000000000 00003660 2**3 + 8 .rodata.str1.8 000002a7 0000000000000000 0000000000000000 00003660 2**3 - 10 .rodata 00001080 0000000000000000 0000000000000000 00003960 2**5 + 10 .rodata 000010e0 0000000000000000 0000000000000000 00003960 2**5 - 15 .data 00001050 0000000000000000 0000000000000000 00004e40 2**5 + 15 .data 00001090 0000000000000000 0000000000000000 00004ea0 2**5 I'm not entirely sure where it comes from, it may be related to instrumentation caused by debugging options. For your patch, Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> -- Regards, Laurent Pinchart