2013/2/8 Geert Uytterhoeven <[email protected]>: > On Thu, Feb 7, 2013 at 3:18 PM, Michal Simek <[email protected]> wrote: >> Fix ioreadXXbe and iowriteXXbe functions which did >> additional little endian conversion on native big endian systems. >> Using be_to_cpu (cpu_to_be) conversions with __raw_read/write >> functions have resolved it. >> >> Signed-off-by: Michal Simek <[email protected]> >> CC: Benjamin Herrenschmidt <[email protected]> >> CC: Arnd Bergmann <[email protected]> >> CC: Geert Uytterhoeven <[email protected]> >> CC: Will Deacon <[email protected]> >> CC: [email protected] > > I have one question (see below). Apart from that: > Acked-by: Geert Uytterhoeven <[email protected]> > >> -#define ioread16be(addr) be16_to_cpu(ioread16(addr)) >> +#define ioread16be(addr) __be16_to_cpu(__raw_readw(addr)) > > Why did you change it to the __beX_to_cpu variant with underscores?
The question could be probably different. Why are they even defined? I have grepped the kernel and all archs use these generic macros include/linux/byteorder/generic.h:94:#define be32_to_cpu __be32_to_cpu include/linux/byteorder/generic.h:106:#define be32_to_cpup __be32_to_cpup include/linux/byteorder/generic.h:118:#define be32_to_cpus __be32_to_cpus What about to remove them? Back to you question. I can't remember particular reason for that maybe just experience that __ versions should be the fastest kernel implementation. Thanks, Michal -- Michal Simek, Ing. (M.Eng) w: www.monstr.eu p: +42-0-721842854 Maintainer of Linux kernel - Microblaze cpu - http://www.monstr.eu/fdt/ Maintainer of Linux kernel - Xilinx Zynq ARM architecture Microblaze U-BOOT custodian and responsible for u-boot arm zynq platform -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
