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    SubjectRe: Why can't we sleep in an ISR?
    > >
    > > I don't think so but I am not sure.
    > Aliter, i think so.How can an interrupt's execution time go
    > unaccounted then?
    > I guess it does not, only the current processes running
    > time is accounted for.
    > Thoughts?

    The interrupt handler's execution time will definitely defer the
    execution of the process, but I think it does not steal the process's
    time slice (the time_slice field not subtracted).

    > > > Doesn't it run in current process's context ?
    > > >
    > >
    > > No. I think the concept of process context is a higher-level logical
    > > concept. Though the interrupt share stack with the interrupted
    > > process, in my opinion it logically does not share the context with
    > > the process.
    > Yes, you are right as i can infer. thats why ISRs
    > are special kernel control paths.
    > But the poster asked, why can't we make ISRs to
    > share context with the interrupted process
    > if
    > it not holding any locks? This is rather a desing issues
    > IMO rather than imlementation, isnt it?
    > I guess even if it is possible, it would over complicate the handler code.
    > Better trying to keep it simple i guess. Please CMIIW

    My understanding is, the ISR is in different context from the process
    because of the definition of term *context*. In my opinion, to say two
    code pieces running in the same context means that two pieces of code
    has some logical relationship to meet a common objective. That's why I
    said *context* is a higher-level logical concept. It's not a concept
    defined in the level of hardware or code implementation, but instead
    in the level of logical. I think, by its definition, it makes no sense
    to say an ISR share context with the process interrupted by it because
    an ISR just randomly interrupts a process, with no logical
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