On Mon, Nov 16, 2020 at 06:42:19PM +0100, Thomas Gleixner wrote: > On Mon, Nov 16 2020 at 13:17, Peter Zijlstra wrote: > > On Fri, Nov 13, 2020 at 03:02:17PM +0100, Thomas Gleixner wrote: > > > >> -#define irq_count() (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK \ > >> - | NMI_MASK)) > >> +#define irq_count() (nmi_count() | hardirq_count() | softirq_count()) > > > > > >> +#define in_task() (!(in_nmi() | in_hardirq() | in_serving_softirq())) > >> -#define in_task() (!(preempt_count() & \ > >> - (NMI_MASK | HARDIRQ_MASK | SOFTIRQ_OFFSET))) > > > > How horrible is the code-gen? Because preempt_count() is > > raw_cpu_read_4() and at least some old compilers will refuse to CSE it > > (consider the this_cpu_read_stable mess). > > I looked at gcc8 and 10 output and the compilers are smart enough to > fold it for the !RT case. But yeah ... If recent GCC is smart enough I suppose it doesn't matter, thanks!