From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f175.google.com (mail-pf0-f175.google.com [209.85.192.175]) by kanga.kvack.org (Postfix) with ESMTP id EEAD16B007E for ; Mon, 21 Mar 2016 07:38:51 -0400 (EDT) Received: by mail-pf0-f175.google.com with SMTP id 4so130865870pfd.0 for ; Mon, 21 Mar 2016 04:38:51 -0700 (PDT) Received: from www262.sakura.ne.jp (www262.sakura.ne.jp. [2001:e42:101:1:202:181:97:72]) by mx.google.com with ESMTPS id e5si7719709pat.66.2016.03.21.04.38.50 for (version=TLS1 cipher=AES128-SHA bits=128/128); Mon, 21 Mar 2016 04:38:50 -0700 (PDT) From: Tetsuo Handa Subject: [PATCH] signal: Make oom_flags a bool Date: Mon, 21 Mar 2016 20:38:13 +0900 Message-Id: <1458560293-24074-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp> Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org Cc: Tetsuo Handa Currently the size of "struct signal_struct"->oom_flags member is sizeof(unsigned) bytes, but only one flag OOM_FLAG_ORIGIN which is updated by current thread is defined. We can convert OOM_FLAG_ORIGIN into a bool, and reuse the saved bytes for updating from the OOM killer and/or the OOM reaper thread. By the way, do we care about a race window between run_store() and swapoff() because it would be theoretically possible that two threads sharing the "struct signal_struct" concurrently call respective functions? If we care, we can make oom_flags an atomic_t. Signed-off-by: Tetsuo Handa --- include/linux/oom.h | 9 +++------ include/linux/sched.h | 6 +++++- include/linux/types.h | 1 - 3 files changed, 8 insertions(+), 8 deletions(-) diff --git a/include/linux/oom.h b/include/linux/oom.h index dad467a..96da253 100644 --- a/include/linux/oom.h +++ b/include/linux/oom.h @@ -50,24 +50,21 @@ enum oom_scan_t { OOM_SCAN_SELECT, /* always select this thread first */ }; -/* Thread is the potential origin of an oom condition; kill first on oom */ -#define OOM_FLAG_ORIGIN ((__force oom_flags_t)0x1) - extern struct mutex oom_lock; static inline void set_current_oom_origin(void) { - current->signal->oom_flags |= OOM_FLAG_ORIGIN; + current->signal->oom_flag_origin = true; } static inline void clear_current_oom_origin(void) { - current->signal->oom_flags &= ~OOM_FLAG_ORIGIN; + current->signal->oom_flag_origin = false; } static inline bool oom_task_origin(const struct task_struct *p) { - return !!(p->signal->oom_flags & OOM_FLAG_ORIGIN); + return p->signal->oom_flag_origin; } extern void mark_oom_victim(struct task_struct *tsk); diff --git a/include/linux/sched.h b/include/linux/sched.h index 888bc15..83bd309b 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -784,7 +784,11 @@ struct signal_struct { struct tty_audit_buf *tty_audit_buf; #endif - oom_flags_t oom_flags; + /* + * Thread is the potential origin of an oom condition; kill first on + * oom + */ + bool oom_flag_origin; short oom_score_adj; /* OOM kill score adjustment */ short oom_score_adj_min; /* OOM kill score adjustment min value. * Only settable by CAP_SYS_RESOURCE. */ diff --git a/include/linux/types.h b/include/linux/types.h index 70dd3df..baf7183 100644 --- a/include/linux/types.h +++ b/include/linux/types.h @@ -156,7 +156,6 @@ typedef u32 dma_addr_t; typedef unsigned __bitwise__ gfp_t; typedef unsigned __bitwise__ fmode_t; -typedef unsigned __bitwise__ oom_flags_t; #ifdef CONFIG_PHYS_ADDR_T_64BIT typedef u64 phys_addr_t; -- 1.8.3.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org