From: Sebastian Andrzej Siewior Date: Tue, 12 Feb 2019 15:09:38 +0100 Subject: [PATCH 265/353] kthread: add a global worker thread. Origin: https://git.kernel.org/cgit/linux/kernel/git/rt/linux-stable-rt.git/commit?id=94597b54548d7027857d3bf84a450098c8ca1953 [ Upstream commit 0532e87d9d44795221aa921ba7024bde689cc894 ] Add kthread_schedule_work() which uses a global kthread for all its jobs. Split the cgroup include to avoid recussive includes from interrupt.h. Fixup everything that fails to build (and did not include all header). Signed-off-by: Sebastian Andrzej Siewior [ Fixed up include in blk-cgroup.h reported by Juri Lelli http://lkml.kernel.org/r/20190722083009.GE25636@localhost.localdomain ] Signed-off-by: Steven Rostedt (VMware) --- drivers/block/loop.c | 2 +- drivers/spi/spi-rockchip.c | 1 + include/linux/blk-cgroup.h | 2 +- include/linux/kthread-cgroup.h | 17 +++++++++++++++++ include/linux/kthread.h | 17 +++++++---------- init/main.c | 1 + kernel/kthread.c | 14 ++++++++++++++ 7 files changed, 42 insertions(+), 12 deletions(-) create mode 100644 include/linux/kthread-cgroup.h diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 12eb48980df7..b8c2c469ce7e 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -70,7 +70,7 @@ #include #include #include -#include +#include #include #include #include diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c index 185bbdce62b1..63b10236eb05 100644 --- a/drivers/spi/spi-rockchip.c +++ b/drivers/spi/spi-rockchip.c @@ -22,6 +22,7 @@ #include #include #include +#include #define DRIVER_NAME "rockchip-spi" diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h index 8f1be8b49391..dc26ce6d840d 100644 --- a/include/linux/blk-cgroup.h +++ b/include/linux/blk-cgroup.h @@ -14,7 +14,7 @@ * Nauman Rafique */ -#include +#include #include #include #include diff --git a/include/linux/kthread-cgroup.h b/include/linux/kthread-cgroup.h new file mode 100644 index 000000000000..53d34bca9d72 --- /dev/null +++ b/include/linux/kthread-cgroup.h @@ -0,0 +1,17 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_KTHREAD_CGROUP_H +#define _LINUX_KTHREAD_CGROUP_H +#include +#include + +#ifdef CONFIG_BLK_CGROUP +void kthread_associate_blkcg(struct cgroup_subsys_state *css); +struct cgroup_subsys_state *kthread_blkcg(void); +#else +static inline void kthread_associate_blkcg(struct cgroup_subsys_state *css) { } +static inline struct cgroup_subsys_state *kthread_blkcg(void) +{ + return NULL; +} +#endif +#endif diff --git a/include/linux/kthread.h b/include/linux/kthread.h index e0498e46d642..31140f0a6c2c 100644 --- a/include/linux/kthread.h +++ b/include/linux/kthread.h @@ -4,7 +4,6 @@ /* Simple interface for creating and stopping kernel threads without mess. */ #include #include -#include __printf(4, 5) struct task_struct *kthread_create_on_node(int (*threadfn)(void *data), @@ -109,7 +108,7 @@ struct kthread_delayed_work { }; #define KTHREAD_WORKER_INIT(worker) { \ - .lock = __SPIN_LOCK_UNLOCKED((worker).lock), \ + .lock = __RAW_SPIN_LOCK_UNLOCKED((worker).lock), \ .work_list = LIST_HEAD_INIT((worker).work_list), \ .delayed_work_list = LIST_HEAD_INIT((worker).delayed_work_list),\ } @@ -201,14 +200,12 @@ bool kthread_cancel_delayed_work_sync(struct kthread_delayed_work *work); void kthread_destroy_worker(struct kthread_worker *worker); -#ifdef CONFIG_BLK_CGROUP -void kthread_associate_blkcg(struct cgroup_subsys_state *css); -struct cgroup_subsys_state *kthread_blkcg(void); -#else -static inline void kthread_associate_blkcg(struct cgroup_subsys_state *css) { } -static inline struct cgroup_subsys_state *kthread_blkcg(void) +extern struct kthread_worker kthread_global_worker; +void kthread_init_global_worker(void); + +static inline bool kthread_schedule_work(struct kthread_work *work) { - return NULL; + return kthread_queue_work(&kthread_global_worker, work); } -#endif + #endif /* _LINUX_KTHREAD_H */ diff --git a/init/main.c b/init/main.c index 703b627a6060..8555afc3f3e1 100644 --- a/init/main.c +++ b/init/main.c @@ -1136,6 +1136,7 @@ static noinline void __init kernel_init_freeable(void) smp_prepare_cpus(setup_max_cpus); workqueue_init(); + kthread_init_global_worker(); init_mm_internals(); diff --git a/kernel/kthread.c b/kernel/kthread.c index c8cf4731ced8..6bbd391f0d9c 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -20,6 +20,7 @@ #include #include #include +#include #include static DEFINE_SPINLOCK(kthread_create_lock); @@ -1244,6 +1245,19 @@ void kthread_destroy_worker(struct kthread_worker *worker) } EXPORT_SYMBOL(kthread_destroy_worker); +DEFINE_KTHREAD_WORKER(kthread_global_worker); +EXPORT_SYMBOL(kthread_global_worker); + +__init void kthread_init_global_worker(void) +{ + kthread_global_worker.task = kthread_create(kthread_worker_fn, + &kthread_global_worker, + "kswork"); + if (WARN_ON(IS_ERR(kthread_global_worker.task))) + return; + wake_up_process(kthread_global_worker.task); +} + #ifdef CONFIG_BLK_CGROUP /** * kthread_associate_blkcg - associate blkcg to current kthread