John Ogness <john.ogn...@linutronix.de> 于2023年9月15日周五 16:34写道： > > On 2023-09-15, Enlin Mu <enlin...@outlook.com> wrote: > > Sometimes we want to print cpu id of printk() messages to consoles > > > > diff --git a/include/linux/threads.h b/include/linux/threads.h > > index c34173e6c5f1..6700bd9a174f 100644 > > --- a/include/linux/threads.h > > +++ b/include/linux/threads.h > > @@ -34,6 +34,9 @@ > > #define PID_MAX_LIMIT (CONFIG_BASE_SMALL ? PAGE_SIZE * 8 : \ > > (sizeof(long) > 4 ? 4 * 1024 * 1024 : PID_MAX_DEFAULT)) > > > > +#define CPU_ID_SHIFT 23 > > +#define CPU_ID_MASK 0xff800000 > > This only supports 256 CPUs. I think it doesn't make sense to try to > squish CPU and Task IDs into 32 bits. Yes, it is not good way, > > What about introducing a caller_id option to always only print the CPU > ID? Or do you really need Task _and_ CPU? Yes, I need it.Because I need to know which CPU is printing the log, so that I can identify the current system operation, such as load situation and CPU busy/idle status > > John Ogness
Thanks Enlin
