From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752490AbeDSK65 (ORCPT ); Thu, 19 Apr 2018 06:58:57 -0400 Received: from foss.arm.com ([217.140.101.70]:35792 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751228AbeDSK6z (ORCPT ); Thu, 19 Apr 2018 06:58:55 -0400 From: Dave Martin To: linux-kernel@vger.kernel.org Cc: Catalin Marinas , Will Deacon , Ralf Baechle , James Hogan , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , "David S. Miller" , Ingo Molnar , Peter Zijlstra , Steven Rostedt , Oleg Nesterov , linux-arch@vger.kernel.org Subject: [RFC PATCH 0/6] Simplify setting thread flags to a particular value Date: Thu, 19 Apr 2018 11:58:42 +0100 Message-Id: <1524135528-28561-1-git-send-email-Dave.Martin@arm.com> X-Mailer: git-send-email 2.1.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There are a number of bits of code sprinkled around the kernel to set a thread flag if a certain condition is true, and clear it otherwise. To help make those call sites terser and less cumbersome, this patch adds a new family of thread flag manipulators update*_thread_flag([...,] flag, cond) See patch 1 for details. Reviewers please pay close attention to accidental conversion of set_tsk_thread_flag() to set_thread_flag() for example, and accidental inversion of conditions. I'm pretty sure neither happens, but build-testing can't pick these up. Build-tested on x86 and the explicitly patched architectures (defconfig and multi_v7_defconfig for arm, defconfig for arm64, mips, powerpc, sparc). Boot-tested on arm64, with some context-switch stress tests that depend on correct maintenance of TIF_FOREIGN_FPSTATE. Background rationale: I've found myself coding this idiom a few times now and would like to stop duplicating it. Using an ungainly lash-up of sed and grep I tried to find other users of the same idiom without too many false positives, and there while there aren't a huge number it seemed enough to be worth having a go at a simple cleanup. The core changes are in the first patch; other changes are split per-arch. Dave Martin (6): thread_info: Add update_thread_flag() helpers ARM: Use update_thread_flag() arm64: Use update{,_tsk}_thread_flag() MIPS: Use update{,_tsk}_thread_flag() powerpc: Use update_thread_flag() sparc: Use update_thread_flag() arch/arm/kernel/elf.c | 9 +++------ arch/arm64/kernel/fpsimd.c | 19 +++++++------------ arch/mips/kernel/elf.c | 10 ++-------- arch/mips/kernel/process.c | 15 ++++++--------- arch/mips/kernel/ptrace.c | 5 +---- arch/mips/kernel/syscall.c | 10 ++-------- arch/powerpc/include/asm/elf.h | 10 ++-------- arch/sparc/include/asm/elf_64.h | 5 +---- include/linux/sched.h | 6 ++++++ include/linux/thread_info.h | 11 +++++++++++ include/trace/syscall.h | 6 ++---- kernel/ptrace.c | 13 +++++-------- 12 files changed, 48 insertions(+), 71 deletions(-) -- 2.1.4