From ac96b737cdec77023bf2ead142a3875174af0c7a Mon Sep 17 00:00:00 2001 From: Bhaktipriya Shridhar Date: Sat, 2 Jul 2016 14:27:06 +0530 Subject: [PATCH] spi: spi-mpc52xx-psc: Remove deprecated create_singlethread_workqueue The workqueue "workqueue" has a single work item(&mps->work) doesn't require ordering. Also, it is not being used on a memory reclaim path. Hence, the singlethreaded workqueue has been replaced with the use of system_wq. System workqueues have been able to handle high level of concurrency for a long time now and hence it's not required to have a singlethreaded workqueue just to gain concurrency. Unlike a dedicated per-cpu workqueue created with create_singlethread_workqueue(), system_wq allows multiple work items to overlap executions even on the same CPU; however, a per-cpu workqueue doesn't have any CPU locality or global ordering guarantee unless the target CPU is explicitly specified and thus the increase of local concurrency shouldn't make any difference. Work item has been flushed in mpc52xx_psc_spi_of_remove() to ensure that nothing is pending while disconnecting the driver. Signed-off-by: Bhaktipriya Shridhar Acked-by: Tejun Heo Signed-off-by: Mark Brown --- drivers/spi/spi-mpc52xx-psc.c | 17 +++-------------- 1 file changed, 3 insertions(+), 14 deletions(-) diff --git a/drivers/spi/spi-mpc52xx-psc.c b/drivers/spi/spi-mpc52xx-psc.c index 72d11ebefb28..42a8b8521f8f 100644 --- a/drivers/spi/spi-mpc52xx-psc.c +++ b/drivers/spi/spi-mpc52xx-psc.c @@ -42,7 +42,6 @@ struct mpc52xx_psc_spi { u8 bits_per_word; u8 busy; - struct workqueue_struct *workqueue; struct work_struct work; struct list_head queue; @@ -299,7 +298,7 @@ static int mpc52xx_psc_spi_transfer(struct spi_device *spi, spin_lock_irqsave(&mps->lock, flags); list_add_tail(&m->queue, &mps->queue); - queue_work(mps->workqueue, &mps->work); + schedule_work(&mps->work); spin_unlock_irqrestore(&mps->lock, flags); return 0; @@ -425,21 +424,12 @@ static int mpc52xx_psc_spi_do_probe(struct device *dev, u32 regaddr, INIT_WORK(&mps->work, mpc52xx_psc_spi_work); INIT_LIST_HEAD(&mps->queue); - mps->workqueue = create_singlethread_workqueue( - dev_name(master->dev.parent)); - if (mps->workqueue == NULL) { - ret = -EBUSY; - goto free_irq; - } - ret = spi_register_master(master); if (ret < 0) - goto unreg_master; + goto free_irq; return ret; -unreg_master: - destroy_workqueue(mps->workqueue); free_irq: free_irq(mps->irq, mps); free_master: @@ -484,8 +474,7 @@ static int mpc52xx_psc_spi_of_remove(struct platform_device *op) struct spi_master *master = spi_master_get(platform_get_drvdata(op)); struct mpc52xx_psc_spi *mps = spi_master_get_devdata(master); - flush_workqueue(mps->workqueue); - destroy_workqueue(mps->workqueue); + flush_work(&mps->work); spi_unregister_master(master); free_irq(mps->irq, mps); if (mps->psc) -- 2.20.1