diff options
| author | Heiko Carstens <heiko.carstens@de.ibm.com> | 2016-10-19 19:28:11 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-10-20 13:27:47 +0200 |
| commit | c8061485a0d7569a865a3cc3c63347b0f42b3765 (patch) | |
| tree | f3c6e686eb2960f0b105c7ec28941fd0d67aff04 | |
| parent | ed1e7db33c3354e4f8b594738c5e793690213b43 (diff) | |
sched/core, x86: Make struct thread_info arch specific again
The following commit:
c65eacbe290b ("sched/core: Allow putting thread_info into task_struct")
... made 'struct thread_info' a generic struct with only a
single ::flags member, if CONFIG_THREAD_INFO_IN_TASK_STRUCT=y is
selected.
This change however seems to be quite x86 centric, since at least the
generic preemption code (asm-generic/preempt.h) assumes that struct
thread_info also has a preempt_count member, which apparently was not
true for x86.
We could add a bit more #ifdefs to solve this problem too, but it seems
to be much simpler to make struct thread_info arch specific
again. This also makes the conversion to THREAD_INFO_IN_TASK_STRUCT a
bit easier for architectures that have a couple of arch specific stuff
in their thread_info definition.
The arch specific stuff _could_ be moved to thread_struct. However
keeping them in thread_info makes it easier: accessing thread_info
members is simple, since it is at the beginning of the task_struct,
while the thread_struct is at the end. At least on s390 the offsets
needed to access members of the thread_struct (with task_struct as
base) are too large for various asm instructions. This is not a
problem when keeping these members within thread_info.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: keescook@chromium.org
Cc: linux-arch@vger.kernel.org
Link: http://lkml.kernel.org/r/1476901693-8492-2-git-send-email-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | arch/x86/include/asm/thread_info.h | 9 | ||||
| -rw-r--r-- | include/linux/thread_info.h | 11 |
2 files changed, 9 insertions, 11 deletions
diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index 2aaca53c0974..ad6f5eb07a95 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -52,6 +52,15 @@ struct task_struct; #include <asm/cpufeature.h> #include <linux/atomic.h> +struct thread_info { + unsigned long flags; /* low level flags */ +}; + +#define INIT_THREAD_INFO(tsk) \ +{ \ + .flags = 0, \ +} + #define init_stack (init_thread_union.stack) #else /* !__ASSEMBLY__ */ diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h index 45f004e9cc59..2873baf5372a 100644 --- a/include/linux/thread_info.h +++ b/include/linux/thread_info.h @@ -14,17 +14,6 @@ struct timespec; struct compat_timespec; #ifdef CONFIG_THREAD_INFO_IN_TASK -struct thread_info { - unsigned long flags; /* low level flags */ -}; - -#define INIT_THREAD_INFO(tsk) \ -{ \ - .flags = 0, \ -} -#endif - -#ifdef CONFIG_THREAD_INFO_IN_TASK #define current_thread_info() ((struct thread_info *)current) #endif |