Messages in this thread | | | Date | Wed, 27 Nov 2002 16:13:05 -0500 | From | Linux Geek <> | Subject | Re: Question about copy_from/copy_to |
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Richard,
Thanks fpr your response,
Yup, it's "political" this project is "work for hire" for an internal system - the code will never be distributed - all very hush hush. (I signed a non-disclosure agreement - so I can't be too specific.)
In essence, memory is allocated for each minor device number (total number of minors and the values are unknown at init time), and the data stored in a linked list. So for each open, the list is searched, and if the minor number is found, that is what is used (and a counter incremented), otherwise memory is allocated ad added to the list. (BTW - this is not my design and they're paying the bill.)
On the close the memory counter is decremented for the minor, and if zero, the memory is deallocated, So, it sounds like this is OK,
Richard B. Johnson wrote: >... > So, I would say that it's not a good idea to allocate memory during > an open(). If you some political reason, you are forced to do this, > you need to count the number of open/close operations and only > deallocate memory after the final close. There are atomic-counter > macros you can use for this. > > Cheers, > Dick Johnson > Penguin : Linux version 2.4.18 on an i686 machine (797.90 BogoMips). > Bush : The Fourth Reich of America > >
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