[POWERPC] spufs: fix invalid scheduling of forgotten contexts
authorJeremy Kerr <jk@ozlabs.org>
Wed, 27 Feb 2008 08:08:13 +0000 (19:08 +1100)
committerJeremy Kerr <jk@ozlabs.org>
Wed, 27 Feb 2008 22:56:28 +0000 (09:56 +1100)
commit0111a701867a796a7ca6ecbc385e4befc9f35066
tree941a3737fa3a0ee56fbdfc164a6a2f4411d08d6f
parentd58831375d68a3bd39d5ebab9eca711fbb4ee108
[POWERPC] spufs: fix invalid scheduling of forgotten contexts

At present, we have a situation where a context with no owner is
re-scheduled by spu_forget:

Thread 1: reading regs file Thread 2: context owner

spu_forget()
- ctx->owner = NULL
- set SPU_SCHED_WAS_ACTIVE

spu_acquire_saved()
- context is in saved state

spu_release_saved()
- SPU_SCHED_WAS_ACTIVE is set,
  so spu_activate() the context,
  which now has no owner

In spu_forget(), we shouldn't be requesting a re-schedule by setting
SPU_SCHED_WAS_ACTIVE. This change removes the set_bit in spu_forget(),
so that spu_release_saved() doesn't reinsert this destroyed context on
to the run queue.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
arch/powerpc/platforms/cell/spufs/context.c