Hi,
On Sun, 23 Feb 2003, Kevin O'Connor wrote:
> 8) Have the unregister code (remove_proc_entry) set an external flag (eg,
> de->data_is_there), and update all users of de->data to check the flag
> before following the pointer.
>
> Option 8 may not qualify as "sane", but I think it is important to add it
> because it is what the module code is currently using. Thus, one need not
> look at the module stuff as a "special case", but as a general (if
> complicated) resource management solution.
Yes, it's another possible solution, but it has the same problem as the
current module locking - increased locking complexity.
Such flag actually exists already ("deleted"), but no user can use it
currently, because the read/write functions don't have the proc entry
argument. Even if they could use it, switching this flag isn't enough
remove_proc_entry also had to synchronize with active users, so users had
to take some lock just to read the data, where a simple reference was
sufficient before.
bye, Roman
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This archive was generated by hypermail 2b29 : Fri Feb 28 2003 - 22:00:18 EST