Hi Sri, Replying to the list this time... On Thu, Sep 9, 2010 at 9:58 PM, Sri Ram Vemulpali <sri.ram.gmu06@xxxxxxxxx> wrote: > Hi Dave, > Thanks for explanation, but is there any delay between interrupt handler > and softirq execution. Suppose say INT7 triggered and its handler got > executed. Now this handler raised the softirq and finished its interrupt > context. Since interrupts preempts the current running task, after finishing > IRQ context does the task should resumes. But since softirq was scheduled > (raised), then is it that softirq will be executed immediately after > interrupt handler or it takes some time when interrupted task was switched > out and scheduler recognizes a softirq was pending. I know that ksoftirqd is > responsible to execute all pending softirqs , who will invoke this, and for > every periodic time ksoftirqd invokes and executes softirq. Can you please > explain. Thanks. Under a normally loaded system, the softirq will run as soon as the hardirq stack unwinds (i.e. there are no pending hardirqs). However, if a softirq is triggered for a second time while softirqs are being handled, the ksoftirqd is triggered to process the softirqs in a task context. So yes, it is possible for there to be a delay between the hardirq completing and the softirq executing. -- Dave Hylands Shuswap, BC, Canada http://www.DaveHylands.com/ -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
