Hello:
About the 'device manager' or 'i/o system', some devices need to be acceced one by one, but:
The mutual exclusion (MUTEX) is usually implemented at kernel level? Or at 'device driver' level?
Thank you very much!
pepito
MUTEX
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EyeScream
RE:MUTEX
A mutex is a shared memory object, and its use might (and probably will) go beyond just driver manager. So, there's sense in implementing it at the kernel level, with all necessary optimizations (i.e. you might use a separate memory space -- a non-swapped one -- for such objects, which would allow faster work).
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pepito
RE:MUTEX (again)
Sorry, my eanglish is very bad.
I understand that MUTEX is abbreviation of 'mutual exclusion', a technique used to guarantee that never two process access to a 'shared object' at the same time.
Let me try to make my question again:
Some devices are used concurrently (by many process at the same time) and then a 'semaphore' object is needed to control the access to those devices.
My quiestion is:
This 'semaphore' must be placed into the 'device driver', or at kernel level?
I know it could be as I want, but where it is normally placed?
Again, sorry my poor english...
Thank you very much!
pepito
I understand that MUTEX is abbreviation of 'mutual exclusion', a technique used to guarantee that never two process access to a 'shared object' at the same time.
Let me try to make my question again:
Some devices are used concurrently (by many process at the same time) and then a 'semaphore' object is needed to control the access to those devices.
My quiestion is:
This 'semaphore' must be placed into the 'device driver', or at kernel level?
I know it could be as I want, but where it is normally placed?
Again, sorry my poor english...
Thank you very much!
pepito