I've noticed that there's a lot of misperception about the meaning of the __always_inline, or more specifically, __attribute__((always_inline)), which does not actually cause the function to always be inlined. Rather, it *allows* gcc to inline the function, even when compiling without optimizations. Here is the description of the attribute from gcc's docs (http://gcc.gnu.org/onlinedocs/gcc-4.7.2/gcc/Function-Attributes.html)
always_inline Generally, functions are not inlined unless optimization is specified. For functions declared inline, this attribute inlines the function even if no optimization level was specified. This would even appear to imply that such functions aren't even marked as "inline" (something I wasn't aware of until today). The only mechanism I'm currently aware of to force gcc to inline a function is the flatten attribute (see https://lkml.org/lkml/2012/9/25/643) which works backwards, you declare it on the calling function, and it forces gcc to inline all functions (marked as inline) that it calls. Daniel -- 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/
