Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754296AbcJUFwR (ORCPT ); Fri, 21 Oct 2016 01:52:17 -0400 Received: from terminus.zytor.com ([198.137.202.10]:33288 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750856AbcJUFwO (ORCPT ); Fri, 21 Oct 2016 01:52:14 -0400 Date: Thu, 20 Oct 2016 22:50:05 -0700 From: tip-bot for Heiko Carstens Message-ID: Cc: mark.rutland@arm.com, hpa@zytor.com, torvalds@linux-foundation.org, mingo@kernel.org, tglx@linutronix.de, heiko.carstens@de.ibm.com, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, luto@kernel.org, peterz@infradead.org Reply-To: linux-kernel@vger.kernel.org, akpm@linux-foundation.org, luto@kernel.org, peterz@infradead.org, mark.rutland@arm.com, hpa@zytor.com, torvalds@linux-foundation.org, tglx@linutronix.de, mingo@kernel.org, heiko.carstens@de.ibm.com In-Reply-To: <1476901693-8492-2-git-send-email-mark.rutland@arm.com> References: <1476901693-8492-2-git-send-email-mark.rutland@arm.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/urgent] sched/core, x86: Make struct thread_info arch specific again Git-Commit-ID: c8061485a0d7569a865a3cc3c63347b0f42b3765 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3325 Lines: 94 Commit-ID: c8061485a0d7569a865a3cc3c63347b0f42b3765 Gitweb: http://git.kernel.org/tip/c8061485a0d7569a865a3cc3c63347b0f42b3765 Author: Heiko Carstens AuthorDate: Wed, 19 Oct 2016 19:28:11 +0100 Committer: Ingo Molnar CommitDate: Thu, 20 Oct 2016 13:27:47 +0200 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 Signed-off-by: Mark Rutland Acked-by: Thomas Gleixner Cc: Andrew Morton Cc: Andy Lutomirski Cc: Linus Torvalds Cc: Peter Zijlstra 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 --- arch/x86/include/asm/thread_info.h | 9 +++++++++ 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 2aaca53..ad6f5eb0 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 #include +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 45f004e..2873baf 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