diff options
Diffstat (limited to 'target/linux/generic/patches-3.18/092-03-spi-Only-idle-the-message-pump-in-the-worker-kthread.patch')
-rw-r--r-- | target/linux/generic/patches-3.18/092-03-spi-Only-idle-the-message-pump-in-the-worker-kthread.patch | 83 |
1 files changed, 0 insertions, 83 deletions
diff --git a/target/linux/generic/patches-3.18/092-03-spi-Only-idle-the-message-pump-in-the-worker-kthread.patch b/target/linux/generic/patches-3.18/092-03-spi-Only-idle-the-message-pump-in-the-worker-kthread.patch deleted file mode 100644 index a5d85be2b4..0000000000 --- a/target/linux/generic/patches-3.18/092-03-spi-Only-idle-the-message-pump-in-the-worker-kthread.patch +++ /dev/null @@ -1,83 +0,0 @@ -From: Mark Brown <broonie@kernel.org> -Date: Wed, 10 Dec 2014 13:46:33 +0000 -Subject: [PATCH] spi: Only idle the message pump in the worker kthread - -In order to avoid the situation where the kthread is waiting for another -context to make the hardware idle let the message pump know if it's being -called from the worker thread context and if it isn't then defer to the -worker thread instead of idling the hardware immediately. This will ensure -that if this situation happens we block rather than busy waiting. - -Signed-off-by: Mark Brown <broonie@kernel.org> ---- - ---- a/drivers/spi/spi.c -+++ b/drivers/spi/spi.c -@@ -875,8 +875,9 @@ void spi_finalize_current_transfer(struc - EXPORT_SYMBOL_GPL(spi_finalize_current_transfer); - - /** -- * spi_pump_messages - kthread work function which processes spi message queue -- * @work: pointer to kthread work struct contained in the master struct -+ * __spi_pump_messages - function which processes spi message queue -+ * @master: master to process queue for -+ * @in_kthread: true if we are in the context of the message pump thread - * - * This function checks if there is any spi message in the queue that - * needs processing and if so call out to the driver to initialize hardware -@@ -886,10 +887,8 @@ EXPORT_SYMBOL_GPL(spi_finalize_current_t - * inside spi_sync(); the queue extraction handling at the top of the - * function should deal with this safely. - */ --static void spi_pump_messages(struct kthread_work *work) -+static void __spi_pump_messages(struct spi_master *master, bool in_kthread) - { -- struct spi_master *master = -- container_of(work, struct spi_master, pump_messages); - unsigned long flags; - bool was_busy = false; - int ret; -@@ -916,6 +915,15 @@ static void spi_pump_messages(struct kth - spin_unlock_irqrestore(&master->queue_lock, flags); - return; - } -+ -+ /* Only do teardown in the thread */ -+ if (!in_kthread) { -+ queue_kthread_work(&master->kworker, -+ &master->pump_messages); -+ spin_unlock_irqrestore(&master->queue_lock, flags); -+ return; -+ } -+ - master->busy = false; - master->idling = true; - spin_unlock_irqrestore(&master->queue_lock, flags); -@@ -1004,6 +1012,18 @@ static void spi_pump_messages(struct kth - } - } - -+/** -+ * spi_pump_messages - kthread work function which processes spi message queue -+ * @work: pointer to kthread work struct contained in the master struct -+ */ -+static void spi_pump_messages(struct kthread_work *work) -+{ -+ struct spi_master *master = -+ container_of(work, struct spi_master, pump_messages); -+ -+ __spi_pump_messages(master, true); -+} -+ - static int spi_init_queue(struct spi_master *master) - { - struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 }; -@@ -2165,7 +2185,7 @@ static int __spi_sync(struct spi_device - * can. - */ - if (master->transfer == spi_queued_transfer) -- spi_pump_messages(&master->pump_messages); -+ __spi_pump_messages(master, false); - - wait_for_completion(&done); - status = message->status; |