Re: [PATCH net v1 1/1] bnx2: Fix unused data compilation warning
From: Andy Shevchenko
Date: Mon Apr 14 2025 - 06:11:34 EST
On Wed, Mar 12, 2025 at 06:20:17PM +0200, Andy Shevchenko wrote:
> On Tue, Mar 11, 2025 at 01:51:21PM +0100, Marek Szyprowski wrote:
> > On 05.03.2025 11:00, Andy Shevchenko wrote:
> > > On Tue, Mar 04, 2025 at 08:35:24AM -0800, Jakub Kicinski wrote:
> > >> On Tue, 4 Mar 2025 15:41:19 +0200 Andy Shevchenko wrote:
...
> > >> I meant something more like (untested):
> > > We are starving for the comment from the DMA mapping people.
> >
> > I'm really sorry for this delay. Just got back to the everyday stuff
> > after spending a week in bed recovering from flu...
>
> Oh, I hope you feel much better now!
>
> ...
>
> > >> #define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)
> > >> #define DEFINE_DMA_UNMAP_LEN(LEN_NAME)
> > >> -#define dma_unmap_addr(PTR, ADDR_NAME) (0)
> > >> -#define dma_unmap_addr_set(PTR, ADDR_NAME, VAL) do { } while (0)
> > >> -#define dma_unmap_len(PTR, LEN_NAME) (0)
> > >> -#define dma_unmap_len_set(PTR, LEN_NAME, VAL) do { } while (0)
> > >> +#define dma_unmap_addr(PTR, ADDR_NAME) ({ typeof(PTR) __p __maybe_unused = PTR; 0; )}
> > >> +#define dma_unmap_addr_set(PTR, ADDR_NAME, VAL) do { typeof(PTR) __p __maybe_unused = PTR; } while (0)
> > >> +#define dma_unmap_len(PTR, LEN_NAME) ({ typeof(PTR) __p __maybe_unused = PTR; 0; )}
> > >> +#define dma_unmap_len_set(PTR, LEN_NAME, VAL) do { typeof(PTR) __p __maybe_unused = PTR; } while (0)
>
> > >> I just don't know how much code out there depends on PTR not
> > >> existing if !CONFIG_NEED_DMA_MAP_STATE
> > > Brief checking shows that only drivers/net/ethernet/chelsio/* comes
> > > with ifdeffery, the rest most likely will fail in the same way
> > > (note, overwhelming majority of the users is under the network realm):
> >
> > Frankly speaking I wasn't aware of this API till now.
> >
> > If got it right the above proposal should work fine. The addr/len names
> > can be optimized out, but the pointer to the container should exist.
>
> Thanks for the reply, would you or Jakub will to send a formal patch?
> I can test it on my configuration and build.
Any news here? The problem still persist AFAICT.
--
With Best Regards,
Andy Shevchenko