--- Shripal <shripal_bagadia@yahoo.com> wrote: > I am designing a device driver for linux kernel 2.4. > > When an interrupt occurs, the ISR schedules a tasklet for further > processing. I > have some data that is accessed from both, ioctl and the tasklet. > Do I need to > protect this data using critical section? > If the data is simply read, no. > If user calls ioctl, execution switches to kernel mode. If ioctl is > modifying > the common data structure when an interrupt occurs, can the tasklet > (scheduled > by ISR) run before execution gets back to ioctl? If this is > possible then will > putting the tasklet on scheduler queue avoid such scenario? > I believe that the tasklet *may* run before execution gets back to the ioctl, and "scheduling" the tasklet will not guarantee that it will not. Sounds like the possibility exists for a race condition here. To be safe, protect your data structure! Harmony, --Christine __________________________________________________ Do You Yahoo!? Yahoo! Autos - Get free new car price quotes http://autos.yahoo.com -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
