On Tue, Jul 01, 2003 at 06:22:29PM +0200, Martin Maletinsky wrote: > I know, that you are not allowed to sleep in an interrupt handler. How > ever I am interested to understand the reason(s) for that. Was this > a design decision (e.g. to simplify things) for the Linux kernel, or > is there a fundamental reason that makes sleeping interrupt handlers > simply impossible? What about the page fault handler - it (probably) > sleeps when it has to swap in a page, why is it possible to sleep for > the page fault handler and not for an interrupt handler? Sleeping is implemented using scheduler. Scheduler only schedules tasks (design decision to keep it simple). So you need a task context to sleep in. Interrupt is not tied to a process (and uses stack of whichever happens to be scheduled) so it can't use the context because it does not have to be in a sane state. ------------------------------------------------------------------------------- Jan 'Bulb' Hudec <bulb@ucw.cz> -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
