On Fri, 2012-04-06 at 14:32 -0700, Linus Torvalds wrote: > Ok, as some of you are aware, one of the things that got merged very > early in the 3.4 merge window was the "word-at-a-time" filename lookup > patches I had been working on. They only get enabled on x86, but when > they do, they do speed things up by quite a noticeable bit (mainly on > x86-64, which ends up doing things 8 bytes at a time - it's much less > noticeable on x86-32). Talking of which ... I haven't had much time to look but any reason that wouldn't work on BE platforms as well when they have a fast byteswap-load ? Now powerpc sadly only have up to 32-bit byteswap loads so doing 64-bit requires a bit of shifting around but the result might still be faster than loading individual bytes especially since we do have a bunch of registers to spare.... Something lines of - a = *(unsigned long *)name; + a = le64_to_cpup((__le64 *)name); (etc...) Maybe ? I might have a chance to actually test later today (chasing some regressions goes first) Cheers, Ben. -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
