[PATCH v5 10/20] kthread: Better support freezable kthread workers
flat view
STALE3898d
SUPERSEDED
From: Petr Mladek <pmladek@suse.com>
Date: 2016-02-22 14:58:37
Also in:
linux-mm, lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
Status: Superseded by v6 (posted 2016-04-14). [go to v6]
Revision v5 (6 revisions archived).
Revisions (6)
This patch allows to make kthread worker freezable via a new @flags parameter. It will allow to avoid an init work in some kthreads. It currently does not affect the function of kthread_worker_fn() but it might help to do some optimization or fixes eventually. I currently do not know about any other use for the @flags parameter but I believe that we will want more flags in the future. Finally, I hope that it will not cause confusion with @flags member in struct kthread. Well, I guess that we will want to rework the basic kthreads implementation once all kthreads are converted into kthread workers or workqueues. It is possible that we will merge the two structures. Signed-off-by: Petr Mladek <pmladek@suse.com> --- include/linux/kthread.h | 11 ++++++++--- kernel/kthread.c | 18 ++++++++++++------ 2 files changed, 20 insertions(+), 9 deletions(-)
diff --git a/include/linux/kthread.h b/include/linux/kthread.h
index 531730f8a8a7..b57786c40c2c 100644
--- a/include/linux/kthread.h
+++ b/include/linux/kthread.h@@ -65,7 +65,12 @@ struct kthread_work; typedef void (*kthread_work_func_t)(struct kthread_work *work); void delayed_kthread_work_timer_fn(unsigned long __data); +enum { + KTW_FREEZABLE = 1 << 2, /* freeze during suspend */ +}; + struct kthread_worker { + unsigned int flags; spinlock_t lock; struct list_head work_list; struct list_head delayed_work_list;
@@ -154,12 +159,12 @@ extern void __init_kthread_worker(struct kthread_worker *worker, int kthread_worker_fn(void *worker_ptr); -__printf(1, 2) +__printf(2, 3) struct kthread_worker * -create_kthread_worker(const char namefmt[], ...); +create_kthread_worker(unsigned int flags, const char namefmt[], ...); struct kthread_worker * -create_kthread_worker_on_cpu(int cpu, const char namefmt[]); +create_kthread_worker_on_cpu(int cpu, unsigned int flags, const char namefmt[]); bool queue_kthread_work(struct kthread_worker *worker, struct kthread_work *work);
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 686bdd5b6936..643b3088b8d7 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c@@ -556,11 +556,11 @@ void __init_kthread_worker(struct kthread_worker *worker, const char *name, struct lock_class_key *key) { + memset(worker, 0, sizeof(struct kthread_worker)); spin_lock_init(&worker->lock); lockdep_set_class_and_name(&worker->lock, key, name); INIT_LIST_HEAD(&worker->work_list); INIT_LIST_HEAD(&worker->delayed_work_list); - worker->task = NULL; } EXPORT_SYMBOL_GPL(__init_kthread_worker);
@@ -590,6 +590,10 @@ int kthread_worker_fn(void *worker_ptr) */ WARN_ON(worker->task && worker->task != current); worker->task = current; + + if (worker->flags & KTW_FREEZABLE) + set_freezable(); + repeat: set_current_state(TASK_INTERRUPTIBLE); /* mb paired w/ kthread_stop */
@@ -623,7 +627,8 @@ repeat: EXPORT_SYMBOL_GPL(kthread_worker_fn); static struct kthread_worker * -__create_kthread_worker(int cpu, const char namefmt[], va_list args) +__create_kthread_worker(int cpu, unsigned int flags, + const char namefmt[], va_list args) { struct kthread_worker *worker; struct task_struct *task;
@@ -643,6 +648,7 @@ __create_kthread_worker(int cpu, const char namefmt[], va_list args) if (IS_ERR(task)) goto fail_task; + worker->flags = flags; worker->task = task; wake_up_process(task); return worker;
@@ -661,13 +667,13 @@ fail_task: * when the worker was SIGKILLed. */ struct kthread_worker * -create_kthread_worker(const char namefmt[], ...) +create_kthread_worker(unsigned int flags, const char namefmt[], ...) { struct kthread_worker *worker; va_list args; va_start(args, namefmt); - worker = __create_kthread_worker(-1, namefmt, args); + worker = __create_kthread_worker(-1, flags, namefmt, args); va_end(args); return worker;
@@ -690,9 +696,9 @@ EXPORT_SYMBOL(create_kthread_worker); * when the worker was SIGKILLed. */ struct kthread_worker * -create_kthread_worker_on_cpu(int cpu, const char namefmt[]) +create_kthread_worker_on_cpu(int cpu, unsigned int flags, const char namefmt[]) { - return __create_kthread_worker(cpu, namefmt, NULL); + return __create_kthread_worker(cpu, flags, namefmt, NULL); } EXPORT_SYMBOL(create_kthread_worker_on_cpu);
--
1.8.5.6
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