On Fri, Jan 30, 2009 at 05:54:10PM +0100, Eric Dumazet wrote: > Andi Kleen a écrit : > > Eric Dumazet <dada1@xxxxxxxxxxxxx> writes: > > > >> While doing oprofile tests I noticed two loops are not properly unrolled by gcc > > > > That's because nobody passed -funroll-loops. Did you try that for > > that file? Likely will need -O2 too > > I dont want to unroll all loops, only those two :) gcc 4.4 will have a way to do that per function, but earlier you would need to move it to a separate file and specify the option only for that. Doing so would be still a good idea compared to your patch because the code will be cleaner and might be more adaptable to future architectures (such manual tunings tend to outdate) > I wish gcc (4.3.2 here) was litle bit smarter :( It cannot do much without profile feedback because it has no clue which loops are hot and which are not. > (By the way, I still use the patch on arch/x86/oprofile/op_model_ppro.c > to have a working oprofile on my dev machine...) Yes I know, sorry for that. -Andi -- ak@xxxxxxxxxxxxxxx -- Speaking for myself only. -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
