Messages in this thread | | | Date | Fri, 29 Oct 2004 12:12:07 -0700 (PDT) | From | Linus Torvalds <> | Subject | Re: Semaphore assembly-code bug |
| |
On Fri, 29 Oct 2004, linux-os wrote: > > Linus, there is no way in hell that you are going to move > a value from memory into a register (pop ecx) faster than > you are going to do anything to the stack-pointer or > any other register.
Sorry, but you're wrong.
Learn about modern CPU's some day, and realize that cached accesses are fast, and pipeline stalls are relatively much more expensive.
Now, if it was uncached, you'd have a point.
Also think about why
call xxx jmp yy
is often much faster than
push $yy jmp xxx
and other small interesting facts about how CPU's actually work these days.
Linus - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |