Paolo Bonzini <[email protected]> wrote: > -ftracer can duplicate asm blocks causing compilation to fail in > noclone functions. For example, KVM declares a global variable > in an asm like > > asm("2: ... \n > .pushsection data \n > .global vmx_return \n > vmx_return: .long 2b"); > > and -ftracer causes a double declaration. > > Cc: Andrew Morton <[email protected]> > Cc: Michal Marek <[email protected]> > Cc: [email protected] > Cc: [email protected] > Reported-by: Linda Walsh <[email protected]> > Signed-off-by: Paolo Bonzini <[email protected]> > --- > include/linux/compiler-gcc.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h > index 22ab246feed3..eeae401a2412 100644 > --- a/include/linux/compiler-gcc.h > +++ b/include/linux/compiler-gcc.h > @@ -199,7 +199,7 @@ > #define unreachable() __builtin_unreachable() > > /* Mark a function definition as prohibited from being cloned. */ > -#define __noclone __attribute__((__noclone__)) > +#define __noclone __attribute__((__noclone__, __optimize__("no-tracer")))
[ Bringing the thread back from the dead for context ] Setting different optimization attributes to certain functions apparently prevents gcc from inlining functions with different “optimizations”. This results in poor compilation - most notably of vmx_vcpu_run() - and causes short functions such as to_vmx() not to be inlined. Regards, Nadav
