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| author | Andy Lutomirski | 2016-09-13 23:29:24 +0200 |
|---|---|---|
| committer | Ingo Molnar | 2016-09-15 08:25:13 +0200 |
| commit | c65eacbe290b8141554c71b2c94489e73ade8c8d (patch) | |
| tree | 001c2aa33a3dded758550c659ced4b70e341e03e /include/linux/sched.h | |
| parent | um/Stop conflating task_struct::stack with thread_info (diff) | |
| download | kernel-qcow2-linux-c65eacbe290b8141554c71b2c94489e73ade8c8d.tar.gz kernel-qcow2-linux-c65eacbe290b8141554c71b2c94489e73ade8c8d.tar.xz kernel-qcow2-linux-c65eacbe290b8141554c71b2c94489e73ade8c8d.zip | |
sched/core: Allow putting thread_info into task_struct
If an arch opts in by setting CONFIG_THREAD_INFO_IN_TASK_STRUCT,
then thread_info is defined as a single 'u32 flags' and is the first
entry of task_struct. thread_info::task is removed (it serves no
purpose if thread_info is embedded in task_struct), and
thread_info::cpu gets its own slot in task_struct.
This is heavily based on a patch written by Linus.
Originally-from: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jann Horn <jann@thejh.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/a0898196f0476195ca02713691a5037a14f2aac5.1473801993.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include/linux/sched.h')
| -rw-r--r-- | include/linux/sched.h | 36 |
1 files changed, 34 insertions, 2 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index 20f9f47bcfd0..a287e8b13549 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1458,6 +1458,13 @@ struct tlbflush_unmap_batch { }; struct task_struct { +#ifdef CONFIG_THREAD_INFO_IN_TASK + /* + * For reasons of header soup (see current_thread_info()), this + * must be the first element of task_struct. + */ + struct thread_info thread_info; +#endif volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */ void *stack; atomic_t usage; @@ -1467,6 +1474,9 @@ struct task_struct { #ifdef CONFIG_SMP struct llist_node wake_entry; int on_cpu; +#ifdef CONFIG_THREAD_INFO_IN_TASK + unsigned int cpu; /* current CPU */ +#endif unsigned int wakee_flips; unsigned long wakee_flip_decay_ts; struct task_struct *last_wakee; @@ -2588,7 +2598,9 @@ extern void set_curr_task(int cpu, struct task_struct *p); void yield(void); union thread_union { +#ifndef CONFIG_THREAD_INFO_IN_TASK struct thread_info thread_info; +#endif unsigned long stack[THREAD_SIZE/sizeof(long)]; }; @@ -3076,10 +3088,26 @@ static inline void threadgroup_change_end(struct task_struct *tsk) cgroup_threadgroup_change_end(tsk); } -#ifndef __HAVE_THREAD_FUNCTIONS +#ifdef CONFIG_THREAD_INFO_IN_TASK + +static inline struct thread_info *task_thread_info(struct task_struct *task) +{ + return &task->thread_info; +} +static inline void *task_stack_page(const struct task_struct *task) +{ + return task->stack; +} +#define setup_thread_stack(new,old) do { } while(0) +static inline unsigned long *end_of_stack(const struct task_struct *task) +{ + return task->stack; +} + +#elif !defined(__HAVE_THREAD_FUNCTIONS) #define task_thread_info(task) ((struct thread_info *)(task)->stack) -#define task_stack_page(task) ((task)->stack) +#define task_stack_page(task) ((void *)(task)->stack) static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) { @@ -3379,7 +3407,11 @@ static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume) static inline unsigned int task_cpu(const struct task_struct *p) { +#ifdef CONFIG_THREAD_INFO_IN_TASK + return p->cpu; +#else return task_thread_info(p)->cpu; +#endif } static inline int task_node(const struct task_struct *p) |