2007/2/2, Bahadir Balban <bahadir.balban@xxxxxxxxx>:
Hi, When preemption is disabled, what happens if a timer interrupt occurs when a process is in a system call? I would guess the handler would update process times, and if a schedule is pending, it occurs as soon as the process returns from the system call. Is that correct?
Yes, I think so. In this case, the timer interrupt causes the thread flag TIF_NEED_RESCHED being set, which in turn causes context switch just before the system call returns.
Another question - the irqs are disabled at times (like when a spinlock is held). Does this cause any lost timer ticks?
I guess so.
Thanks, Bahadir -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
-- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
