Re: Why can't we sleep in an ISR?

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



2007/5/16, Phillip Susi <[email protected]>:
Dong Feng wrote:
>> 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.

No, the term context here has a specific meaning.  It refers to those
things which flow from the current pointer, including the virtual memory
space, file descriptor table, current uid, and so forth.  Because the
current pointer is not changed on entry to an ISR, the ISR is executing
in the context of the interrupted process, and thus uses that process'
virtual memory, etc.


If what you say were true, then an ISR would be running in the same
context as the interrupted process. But please check any article or
book, it will say ISR running in different context from any process.
So ISR is considered in its own context, although it shares a lot of
things with the interrupted process. I would only say *context* is a
higher-level logical concept.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux