hi I am new to the kernel world and would be very glad if somebody could help me with this problem. I am unable to do printk or even a macro call like rdtsc()...(for reading the time stamp counter) from within the "activate_task" function on a kernel with smp support.But these work under the main schedule() function. I was able to do all these i.e., inside "activate_task" on a kernel without smp support.Can anybody suggest a solution as to what could be the problem?? somebody please help. Thanks Arun -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/