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2019-05-24treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36Thomas Gleixner1-5/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public licence as published by the free software foundation either version 2 of the licence or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 114 file(s). Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Allison Randal <[email protected]> Reviewed-by: Kate Stewart <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-03-02sched/headers: Prepare to move 'init_task' and 'init_thread_union' from ↵Ingo Molnar1-0/+1
<linux/sched.h> to <linux/sched/task.h> Update all usage sites first. Acked-by: Linus Torvalds <[email protected]> Cc: Mike Galbraith <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Signed-off-by: Ingo Molnar <[email protected]>
2017-03-02sched/headers: Prepare to remove the <linux/mm_types.h> dependency from ↵Ingo Molnar1-0/+1
<linux/sched.h> Update code that relied on sched.h including various MM types for them. This will allow us to remove the <linux/mm_types.h> include from <linux/sched.h>. Acked-by: Linus Torvalds <[email protected]> Cc: Mike Galbraith <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Signed-off-by: Ingo Molnar <[email protected]>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar1-2/+1
<linux/sched/signal.h> We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/signal.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <[email protected]> Cc: Mike Galbraith <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Signed-off-by: Ingo Molnar <[email protected]>
2015-11-06lib/is_single_threaded.c: change current_is_single_threaded() to use ↵Oleg Nesterov1-3/+2
for_each_thread() Change current_is_single_threaded() to use for_each_thread() rather than deprecated while_each_thread(). Signed-off-by: Oleg Nesterov <[email protected]> Cc: David Howells <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2009-07-17kernel: is_current_single_threaded: don't use ->mmap_semOleg Nesterov1-4/+6
is_current_single_threaded() can safely miss a freshly forked CLONE_VM task, but in this case it must not miss its parent. That is why we take mm->mmap_sem for writing to make sure a thread/task with the same ->mm can't pass exit_mm() and disappear. However we can avoid ->mmap_sem and rely on rcu/barriers: - if we do not see the exiting parent on thread/process list we see the result of list_del_rcu(), in this case we must also see the result of list_add_rcu() which does wmb(). - if we do see the parent but its ->mm == NULL, we need rmb() to make sure we can't miss the child. Signed-off-by: Oleg Nesterov <[email protected]> Acked-by: David Howells <[email protected]> Signed-off-by: James Morris <[email protected]>
2009-07-17kernel: rename is_single_threaded(task) to current_is_single_threaded(void)Oleg Nesterov1-1/+2
- is_single_threaded(task) is not safe unless task == current, we can't use task->signal or task->mm. - it doesn't make sense unless task == current, the task can fork right after the check. Rename it to current_is_single_threaded() and kill the argument. Signed-off-by: Oleg Nesterov <[email protected]> Acked-by: David Howells <[email protected]> Signed-off-by: James Morris <[email protected]>
2009-07-17kernel: fix is_single_threadedOleg Nesterov1-26/+36
- Fix the comment, is_single_threaded(p) actually means that nobody shares ->mm with p. I think this helper should be renamed, and it should not have arguments. With or without this patch it must not be used unless p == current, otherwise we can't safely use p->signal or p->mm. - "if (atomic_read(&p->signal->count) != 1)" is not right when we have a zombie group leader, use signal->live instead. - Add PF_KTHREAD check to skip kernel threads which may borrow p->mm, otherwise we can return the wrong "false". - Use for_each_process() instead of do_each_thread(), all threads must use the same ->mm. - Use down_write(mm->mmap_sem) + rcu_read_lock() instead of tasklist_lock to iterate over the process list. If there is another CLONE_VM process it can't pass exit_mm() which takes the same mm->mmap_sem. We can miss a freshly forked CLONE_VM task, but this doesn't matter because we must see its parent and return false. Signed-off-by: Oleg Nesterov <[email protected]> Cc: David Howells <[email protected]> Cc: James Morris <[email protected]> Cc: Roland McGrath <[email protected]> Cc: Stephen Smalley <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: James Morris <[email protected]>
2008-11-14CRED: Rename is_single_threaded() to is_wq_single_threaded()David Howells1-0/+45
Rename is_single_threaded() to is_wq_single_threaded() so that a new is_single_threaded() can be created that refers to tasks rather than waitqueues. Signed-off-by: David Howells <[email protected]> Reviewed-by: James Morris <[email protected]> Signed-off-by: James Morris <[email protected]>