[POWERPC] spufs: optimize spu_run

There is no need to directly wake up contexts in spu_activate when
called from spu_run, so add a flag to surpress this wakeup.

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

diff --git a/arch/powerpc/platforms/cell/spufs/context.c b/arch/powerpc/platforms/cell/spufs/context.c
index 88a8871863039a42f64c7f00abe1dc89b511e1ee..056a8ad0238530c8b7aee3e257679a00ed1d4c34 100644 (file)
--- a/arch/powerpc/platforms/cell/spufs/context.c
+++ b/arch/powerpc/platforms/cell/spufs/context.c
@@ -163,7 +163,7 @@ int spu_acquire_exclusive(struct spu_context *ctx)
  *     Returns 0 and with the context locked on success
  *     Returns negative error and with the context _unlocked_ on failure.
  */
-int spu_acquire_runnable(struct spu_context *ctx)
+int spu_acquire_runnable(struct spu_context *ctx, unsigned long flags)
 {
        int ret = -EINVAL;
 
@@ -174,7 +174,7 @@ int spu_acquire_runnable(struct spu_context *ctx)
                 */
                if (!ctx->owner)
                        goto out_unlock;
-               ret = spu_activate(ctx, 0);
+               ret = spu_activate(ctx, flags);
                if (ret)
                        goto out_unlock;
        }

diff --git a/arch/powerpc/platforms/cell/spufs/file.c b/arch/powerpc/platforms/cell/spufs/file.c
index a528020baa1868ccd5097eee96ad11189aaf2bd9..c729813043a61ffee1a8ad390ecb11cfc776ba98 100644 (file)
--- a/arch/powerpc/platforms/cell/spufs/file.c
+++ b/arch/powerpc/platforms/cell/spufs/file.c
@@ -164,7 +164,7 @@ static unsigned long spufs_ps_nopfn(struct vm_area_struct *vma,
        /* error here usually means a signal.. we might want to test
         * the error code more precisely though
         */
-       ret = spu_acquire_runnable(ctx);
+       ret = spu_acquire_runnable(ctx, 0);
        if (ret)
                return NOPFN_REFAULT;
 
@@ -1306,7 +1306,7 @@ static ssize_t spufs_mfc_write(struct file *file, const char __user *buffer,
        if (ret)
                goto out;
 
-       spu_acquire_runnable(ctx);
+       spu_acquire_runnable(ctx, 0);
        if (file->f_flags & O_NONBLOCK) {
                ret = ctx->ops->send_mfc_command(ctx, &cmd);
        } else {

diff --git a/arch/powerpc/platforms/cell/spufs/run.c b/arch/powerpc/platforms/cell/spufs/run.c
index e1647311044bda7579c311787b1e1a18fbd3d951..a973e79e9fdceb6e9c4b04457d9129b027b0a448 100644 (file)
--- a/arch/powerpc/platforms/cell/spufs/run.c
+++ b/arch/powerpc/platforms/cell/spufs/run.c
@@ -143,7 +143,7 @@ static inline int spu_run_init(struct spu_context *ctx, u32 * npc)
        int ret;
        unsigned long runcntl = SPU_RUNCNTL_RUNNABLE;
 
-       ret = spu_acquire_runnable(ctx);
+       ret = spu_acquire_runnable(ctx, SPU_ACTIVATE_NOWAKE);
        if (ret)
                return ret;
 
@@ -155,7 +155,7 @@ static inline int spu_run_init(struct spu_context *ctx, u32 * npc)
                        spu_release(ctx);
                        ret = spu_setup_isolated(ctx);
                        if (!ret)
-                               ret = spu_acquire_runnable(ctx);
+                               ret = spu_acquire_runnable(ctx, SPU_ACTIVATE_NOWAKE);
                }
 
                /* if userspace has set the runcntrl register (eg, to issue an

diff --git a/arch/powerpc/platforms/cell/spufs/sched.c b/arch/powerpc/platforms/cell/spufs/sched.c
index 6f8e2257c5a6ee664379eafd5847b472fa03c384..07d0d095c62a4d64add130ae0c3c70b8d3bccd11 100644 (file)
--- a/arch/powerpc/platforms/cell/spufs/sched.c
+++ b/arch/powerpc/platforms/cell/spufs/sched.c
@@ -247,8 +247,8 @@ static void spu_prio_wait(struct spu_context *ctx)
 {
        DEFINE_WAIT(wait);
 
+       set_bit(SPU_SCHED_WAKE, &ctx->sched_flags);
        prepare_to_wait_exclusive(&ctx->stop_wq, &wait, TASK_INTERRUPTIBLE);
-
        if (!signal_pending(current)) {
                mutex_unlock(&ctx->state_mutex);
                schedule();
@@ -256,6 +256,7 @@ static void spu_prio_wait(struct spu_context *ctx)
        }
        __set_current_state(TASK_RUNNING);
        remove_wait_queue(&ctx->stop_wq, &wait);
+       clear_bit(SPU_SCHED_WAKE, &ctx->sched_flags);
 }
 
 /**
@@ -275,7 +276,7 @@ static void spu_reschedule(struct spu *spu)
        best = sched_find_first_bit(spu_prio->bitmap);
        if (best < MAX_PRIO) {
                struct spu_context *ctx = spu_grab_context(best);
-               if (ctx)
+               if (ctx && test_bit(SPU_SCHED_WAKE, &ctx->sched_flags))
                        wake_up(&ctx->stop_wq);
        }
        spin_unlock(&spu_prio->runq_lock);
@@ -315,7 +316,7 @@ static struct spu *spu_get_idle(struct spu_context *ctx)
  * add the context to the runqueue so it gets woken up once an spu
  * is available.
  */
-int spu_activate(struct spu_context *ctx, u64 flags)
+int spu_activate(struct spu_context *ctx, unsigned long flags)
 {
 
        if (ctx->spu)
@@ -331,7 +332,8 @@ int spu_activate(struct spu_context *ctx, u64 flags)
                }
 
                spu_add_to_rq(ctx);
-               spu_prio_wait(ctx);
+               if (!(flags & SPU_ACTIVATE_NOWAKE))
+                       spu_prio_wait(ctx);
                spu_del_from_rq(ctx);
        } while (!signal_pending(current));
 

diff --git a/arch/powerpc/platforms/cell/spufs/spufs.h b/arch/powerpc/platforms/cell/spufs/spufs.h
index 7f5a4fc03c0005fac3a858f20fa8d85b28f4448b..421f59167c559d94b97412c4f94bb80dac177a98 100644 (file)
--- a/arch/powerpc/platforms/cell/spufs/spufs.h
+++ b/arch/powerpc/platforms/cell/spufs/spufs.h
@@ -39,6 +39,11 @@ enum {
 struct spu_context_ops;
 struct spu_gang;
 
+/* ctx->sched_flags */
+enum {
+       SPU_SCHED_WAKE = 0,
+};
+
 struct spu_context {
        struct spu *spu;                  /* pointer to a physical SPU */
        struct spu_state csa;             /* SPU context save area. */
@@ -77,6 +82,7 @@ struct spu_context {
 
        /* scheduler fields */
        struct list_head rq;
+       unsigned long sched_flags;
        int prio;
 };
 
@@ -179,10 +185,13 @@ int put_spu_context(struct spu_context *ctx);
 void spu_unmap_mappings(struct spu_context *ctx);
 
 void spu_forget(struct spu_context *ctx);
-int spu_acquire_runnable(struct spu_context *ctx);
+int spu_acquire_runnable(struct spu_context *ctx, unsigned long flags);
 void spu_acquire_saved(struct spu_context *ctx);
 int spu_acquire_exclusive(struct spu_context *ctx);
-int spu_activate(struct spu_context *ctx, u64 flags);
+enum {
+       SPU_ACTIVATE_NOWAKE = 1,
+};
+int spu_activate(struct spu_context *ctx, unsigned long flags);
 void spu_deactivate(struct spu_context *ctx);
 void spu_yield(struct spu_context *ctx);
 int __init spu_sched_init(void);