diff options
Diffstat (limited to 'debian/patches-rt/0003-workqueue-Use-swait-for-wq_manager_wait.patch')
| -rw-r--r-- | debian/patches-rt/0003-workqueue-Use-swait-for-wq_manager_wait.patch | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/debian/patches-rt/0003-workqueue-Use-swait-for-wq_manager_wait.patch b/debian/patches-rt/0003-workqueue-Use-swait-for-wq_manager_wait.patch new file mode 100644 index 000000000..1df8ad7b6 --- /dev/null +++ b/debian/patches-rt/0003-workqueue-Use-swait-for-wq_manager_wait.patch @@ -0,0 +1,54 @@ +From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +Date: Tue, 11 Jun 2019 11:21:09 +0200 +Subject: [PATCH 3/4] workqueue: Use swait for wq_manager_wait +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.4/older/patches-5.4.3-rt1.tar.xz + +In order for the workqueue code use raw_spinlock_t typed locking there +must not be a spinlock_t typed lock be acquired. A wait_queue_head uses +a spinlock_t lock for its list protection. + +Use a swait based queue head to avoid raw_spinlock_t -> spinlock_t +locking. + +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +--- + kernel/workqueue.c | 7 ++++--- + 1 file changed, 4 insertions(+), 3 deletions(-) + +--- a/kernel/workqueue.c ++++ b/kernel/workqueue.c +@@ -50,6 +50,7 @@ + #include <linux/uaccess.h> + #include <linux/sched/isolation.h> + #include <linux/nmi.h> ++#include <linux/swait.h> + + #include "workqueue_internal.h" + +@@ -301,7 +302,7 @@ static struct workqueue_attrs *wq_update + static DEFINE_MUTEX(wq_pool_mutex); /* protects pools and workqueues list */ + static DEFINE_MUTEX(wq_pool_attach_mutex); /* protects worker attach/detach */ + static DEFINE_SPINLOCK(wq_mayday_lock); /* protects wq->maydays list */ +-static DECLARE_WAIT_QUEUE_HEAD(wq_manager_wait); /* wait for manager to go away */ ++static DECLARE_SWAIT_QUEUE_HEAD(wq_manager_wait); /* wait for manager to go away */ + + static LIST_HEAD(workqueues); /* PR: list of all workqueues */ + static bool workqueue_freezing; /* PL: have wqs started freezing? */ +@@ -2137,7 +2138,7 @@ static bool manage_workers(struct worker + + pool->manager = NULL; + pool->flags &= ~POOL_MANAGER_ACTIVE; +- wake_up(&wq_manager_wait); ++ swake_up_one(&wq_manager_wait); + return true; + } + +@@ -3532,7 +3533,7 @@ static void put_unbound_pool(struct work + * manager and @pool gets freed with the flag set. + */ + spin_lock_irq(&pool->lock); +- wait_event_lock_irq(wq_manager_wait, ++ swait_event_lock_irq(wq_manager_wait, + !(pool->flags & POOL_MANAGER_ACTIVE), pool->lock); + pool->flags |= POOL_MANAGER_ACTIVE; + |