• Arnd Bergmann's avatar
    [POWERPC] spufs: Add infrastructure needed for gang scheduling · 6263203e
    Arnd Bergmann authored
    Add the concept of a gang to spufs as a new type of object.
    So far, this has no impact whatsover on scheduling, but makes
    it possible to add that later.
    
    A new type of object in spufs is now a spu_gang. It is created
    with the spu_create system call with the flags argument set
    to SPU_CREATE_GANG (0x2). Inside of a spu_gang, it
    is then possible to create spu_context objects, which until
    now was only possible at the root of spufs.
    
    There is a new member in struct spu_context pointing to
    the spu_gang it belongs to, if any. The spu_gang maintains
    a list of spu_context structures that are its children.
    This information can then be used in the scheduler in the
    future.
    
    There is still a bug that needs to be resolved in this
    basic infrastructure regarding the order in which objects
    are removed. When the spu_gang file descriptor is closed
    before the spu_context descriptors, we leak the dentry
    and inode for the gang. Any ideas how to cleanly solve
    this are appreciated.
    Signed-off-by: default avatarArnd Bergmann <arnd.bergmann@de.ibm.com>
    Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
    6263203e
inode.c 13 KB