Hi, Roy Smith wrote: > in this case, I guess multiple users, on SMP systems, can concurrently Grrrrr. I already told you 2 or 3 times that the problem doesn't only occur on SMP systems, it also occurs on UP systems ! > access the buffer, thus a locking mechanism is required (on the static buffer > alone). Yes, as the buffer is a global shared resource, it has to be protected against concurrent accesses. > on the other hand, automatic variables are created locally for each thread of > execution, > and are not shared amongst the per-cpu thread of execution, so no need to lock > them. > is this true ? Yes local variables (declared inside functions) are allocated on the stack, which is particular to each thread. So there's no need to do locking for local variables. Thomas -- Thomas Petazzoni thomas.petazzoni@xxxxxxxx -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
