[POWERPC] spufs: don't yield CPU in spu_yield

There is no reason to yield the CPU in spu_yield - if the backing
thread reenters spu_run it gets added to the end of the runqueue for
it's priority.  So the yield is just a slowdown for the case where
we have higher priority contexts waiting.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --git a/arch/powerpc/platforms/cell/spufs/sched.c b/arch/powerpc/platforms/cell/spufs/sched.c
index 39823ce..c956158 100644 (file)
--- a/arch/powerpc/platforms/cell/spufs/sched.c
+++ b/arch/powerpc/platforms/cell/spufs/sched.c
@@ -438,7 +438,6 @@ void spu_deactivate(struct spu_context *ctx)
 void spu_yield(struct spu_context *ctx)
 {
        struct spu *spu;
-       int need_yield = 0;
 
        if (mutex_trylock(&ctx->state_mutex)) {
                if ((spu = ctx->spu) != NULL) {
@@ -447,13 +446,10 @@ void spu_yield(struct spu_context *ctx)
                                pr_debug("%s: yielding SPU %d NODE %d\n",
                                         __FUNCTION__, spu->number, spu->node);
                                spu_deactivate(ctx);
-                               need_yield = 1;
                        }
                }
                mutex_unlock(&ctx->state_mutex);
        }
-       if (unlikely(need_yield))
-               yield();
 }
 
 int __init spu_sched_init(void)