[POWERPC] spufs: simplify state_mutex

The r/w semaphore to lock the spus was overkill and can be replaced
with a mutex to make it faster, simpler and easier to debug.  It also
helps to allow making most spufs interruptible in future patches.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/arch/powerpc/platforms/cell/spufs/sched.c b/arch/powerpc/platforms/cell/spufs/sched.c
index 1d330f67f5ae..c61a34b14083 100644
--- a/arch/powerpc/platforms/cell/spufs/sched.c
+++ b/arch/powerpc/platforms/cell/spufs/sched.c
@@ -233,11 +233,11 @@ static void spu_prio_wait(struct spu_context *ctx, u64 flags)
         spu_add_wq(wq, &wait, prio);
 
         if (!signal_pending(current)) {
-                up_write(&ctx->state_sema);
+                mutex_unlock(&ctx->state_mutex);
                 pr_debug("%s: pid=%d prio=%d\n", __FUNCTION__,
                          current->pid, current->prio);
                 schedule();
-                down_write(&ctx->state_sema);
+                mutex_lock(&ctx->state_mutex);
         }
 
         spu_del_wq(wq, &wait, prio);
@@ -334,7 +334,7 @@ void spu_yield(struct spu_context *ctx)
         struct spu *spu;
         int need_yield = 0;
 
-        if (down_write_trylock(&ctx->state_sema)) {
+        if (mutex_trylock(&ctx->state_mutex)) {
                 if ((spu = ctx->spu) != NULL) {
                         int best = sched_find_first_bit(spu_prio->bitmap);
                         if (best < MAX_PRIO) {
@@ -346,7 +346,7 @@ void spu_yield(struct spu_context *ctx)
                                 spu->prio = MAX_PRIO;
                         }
                 }
-                up_write(&ctx->state_sema);
+                mutex_unlock(&ctx->state_mutex);
         }
         if (unlikely(need_yield))
                 yield();