On 09/28/2015 02:33 PM, H. Peter Anvin wrote: > This one makes me slightly nervous, because it isn't clear > that these aren't potentially performance sensitive.
CALL instruction is not a crime :) It costs about the same as one read-modify-write operation on a memory operand. This function is used in signal delivery code. If performance critical code uses massive numbers of signals, it already has a problem, Unix signals are too inefficient. That's why we have futexes etc... > On September 28, 2015 5:23:57 AM PDT, Denys Vlasenko <[email protected]> > wrote: >> This function compiles to 277 bytes of machine code and has 4 >> callsites. I must correct myself: there are two callsites, not four. (There are four calls in the source, but two of them are in 32-bit code and two are in 64-bit). -- 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/
