On 16 Aug 2005 15:15:35 +0200, Andi Kleen <[EMAIL PROTECTED]> wrote: > However it disables preemption, which especially for bigger > copies will probably make the low latency people unhappy.
In the copy loop, +#ifdef CONFIG_PREEMPT + if ( (i%64)==0 ) { + MMX_RESTORE; + MMX_SAVE; + }; +#endif It costs several hundred clocks (wow) every 4KB copy. It kills throughput but it makes the low latency people smile. So I make two APIs. __copy_user_zeroing_nocache() __copy_user_zeroing_inatomic_nocache() The former is a low latency version and the other is a throughput version. What do you think? Regards, Hiro -- Hiro Yoshioka mailto:hyoshiok at miraclelinux.com - 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/