[PATCH] Make fdescfs MPSAFE

[Ulf Lilleengen]

On tor, aug 16, 2007 at 12:05:26 +0200, Ulf Lilleengen wrote:
> Hi,
> 
> To be able to better understand VFS and locking in general, I started making
> fdescfs MPSAFE. I'm not experienced with any of these things, so there might be
> some errors, although I've looked through much VFS code and code for other FS
> like nullfs. I've tested it by running two pthreads on the same fd, and that seamt
> to work, but there might be other cases where it will fail.
> 
> Patch is attached.
>

Attached is a new patch that uses rwlocks instead of mutexes (since reading
the hash_table is frequently done). Also, it adds checking so that there is no
duplicates in the hash table before inserting the new fdescnode. And add a
mising hashfree().

I also checked to see if there was any issues regarding Jeffs new patch to
use atomic operations on the file structure, but there wasn't any obvious
places where this affects fdescfs.

Patch here:
http://folk.ntnu.no/lulf/patches/freebsd/fdescfs/fdescfs_lock.diff

-- 
Ulf Lilleengen