From b8780c363d808a726a34793caa900923d32b6b80 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Mon, 7 Apr 2014 17:33:06 +0200 Subject: [PATCH] sched: remove sleep_on() and friends This is the final piece in the puzzle, as all patches to remove the last users of \(interruptible_\|\)sleep_on\(_timeout\|\) have made it into the 3.15 merge window. The work was long overdue, and this interface in particular should not have survived the BKL removal that was done a couple of years ago. Citing Jon Corbet from http://lwn.net/2001/0201/kernel.php3": "[...] it was suggested that the janitors look for and fix all code that calls sleep_on() [...] since (1) almost all such code is incorrect, and (2) Linus has agreed that those functions should be removed in the 2.5 development series". We haven't quite made it for 2.5, but maybe we can merge this for 3.15. Signed-off-by: Arnd Bergmann Cc: Peter Zijlstra Cc: Ingo Molnar Signed-off-by: Linus Torvalds --- Documentation/DocBook/kernel-hacking.tmpl | 10 ----- include/linux/wait.h | 11 ------ kernel/sched/core.c | 46 ----------------------- 3 files changed, 67 deletions(-) diff --git a/Documentation/DocBook/kernel-hacking.tmpl b/Documentation/DocBook/kernel-hacking.tmpl index d0758b241b23..bd9015d10cff 100644 --- a/Documentation/DocBook/kernel-hacking.tmpl +++ b/Documentation/DocBook/kernel-hacking.tmpl @@ -850,16 +850,6 @@ printk(KERN_INFO "my ip: %pI4\n", &ipaddress); -ERESTARTSYS if a signal is received. The wait_event() version ignores signals. - - Do not use the sleep_on() function family - - it is very easy to accidentally introduce races; almost certainly - one of the wait_event() family will do, or a - loop around schedule_timeout(). If you choose - to loop around schedule_timeout() remember - you must set the task state (with - set_current_state()) on each iteration to avoid - busy-looping. - diff --git a/include/linux/wait.h b/include/linux/wait.h index 559044c79232..e7d9d9ed14f5 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -803,17 +803,6 @@ do { \ __ret; \ }) - -/* - * These are the old interfaces to sleep waiting for an event. - * They are racy. DO NOT use them, use the wait_event* interfaces above. - * We plan to remove these interfaces. - */ -extern void sleep_on(wait_queue_head_t *q); -extern long sleep_on_timeout(wait_queue_head_t *q, signed long timeout); -extern void interruptible_sleep_on(wait_queue_head_t *q); -extern long interruptible_sleep_on_timeout(wait_queue_head_t *q, signed long timeout); - /* * Waitqueues which are removed from the waitqueue_head at wakeup time */ diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 1d1b87b36778..0ff3f34bc7e3 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2845,52 +2845,6 @@ int default_wake_function(wait_queue_t *curr, unsigned mode, int wake_flags, } EXPORT_SYMBOL(default_wake_function); -static long __sched -sleep_on_common(wait_queue_head_t *q, int state, long timeout) -{ - unsigned long flags; - wait_queue_t wait; - - init_waitqueue_entry(&wait, current); - - __set_current_state(state); - - spin_lock_irqsave(&q->lock, flags); - __add_wait_queue(q, &wait); - spin_unlock(&q->lock); - timeout = schedule_timeout(timeout); - spin_lock_irq(&q->lock); - __remove_wait_queue(q, &wait); - spin_unlock_irqrestore(&q->lock, flags); - - return timeout; -} - -void __sched interruptible_sleep_on(wait_queue_head_t *q) -{ - sleep_on_common(q, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); -} -EXPORT_SYMBOL(interruptible_sleep_on); - -long __sched -interruptible_sleep_on_timeout(wait_queue_head_t *q, long timeout) -{ - return sleep_on_common(q, TASK_INTERRUPTIBLE, timeout); -} -EXPORT_SYMBOL(interruptible_sleep_on_timeout); - -void __sched sleep_on(wait_queue_head_t *q) -{ - sleep_on_common(q, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); -} -EXPORT_SYMBOL(sleep_on); - -long __sched sleep_on_timeout(wait_queue_head_t *q, long timeout) -{ - return sleep_on_common(q, TASK_UNINTERRUPTIBLE, timeout); -} -EXPORT_SYMBOL(sleep_on_timeout); - #ifdef CONFIG_RT_MUTEXES /* -- 2.34.1