On Wed, Jul 22, 2020 at 12:09 PM Steven Rostedt <rostedt@xxxxxxxxxxx> wrote: > > On Wed, 22 Jul 2020 20:41:37 +0200 > Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote: > > > > That said, Andi Kleen added an option to gcc called -mnop-mcount which > > > will have gcc do both create the mcount section and convert the calls > > > into nops. When doing so, it defines CC_USING_NOP_MCOUNT which will > > > tell ftrace to expect the calls to already be converted. > > > > That seems like the much easier solution, then we can forget about > > recordmcount / objtool entirely for this. > > Of course that was only for some gcc compilers, and I'm not sure if > clang can do this. > > Or do you just see all compilers doing this in the future, and not > worrying about record-mcount at all, and bothering with objtool? Clang appears to only support -mrecord-mcount and -mnop-mcount for s390, so we still need recordmcount / objtool for x86. Sami
