Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752773AbcDZM7j (ORCPT ); Tue, 26 Apr 2016 08:59:39 -0400 Received: from mail-wm0-f68.google.com ([74.125.82.68]:35874 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752195AbcDZM4h (ORCPT ); Tue, 26 Apr 2016 08:56:37 -0400 From: Michal Hocko To: , Andrew Morton Cc: LKML , Michal Hocko , "Kirill A. Shutemov" , Oleg Nesterov , Andrea Arcangeli , Vlastimil Babka Subject: [PATCH 06/18] mm: make vm_brk killable Date: Tue, 26 Apr 2016 14:56:13 +0200 Message-Id: <1461675385-5934-7-git-send-email-mhocko@kernel.org> X-Mailer: git-send-email 2.8.0.rc3 In-Reply-To: <1461675385-5934-1-git-send-email-mhocko@kernel.org> References: <1461675385-5934-1-git-send-email-mhocko@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1738 Lines: 51 From: Michal Hocko Now that all the callers handle vm_brk failure we can change it wait for mmap_sem killable to help oom_reaper to not get blocked just because vm_brk gets blocked behind mmap_sem readers. Cc: "Kirill A. Shutemov" Cc: Oleg Nesterov Cc: Andrea Arcangeli Acked-by: Vlastimil Babka Signed-off-by: Michal Hocko --- include/linux/mm.h | 2 +- mm/mmap.c | 9 +++------ 2 files changed, 4 insertions(+), 7 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 1085e025852a..7b52750caf9e 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2003,7 +2003,7 @@ static inline void mm_populate(unsigned long addr, unsigned long len) {} #endif /* These take the mm semaphore themselves */ -extern unsigned long vm_brk(unsigned long, unsigned long); +extern unsigned long __must_check vm_brk(unsigned long, unsigned long); extern int vm_munmap(unsigned long, size_t); extern unsigned long __must_check vm_mmap(struct file *, unsigned long, unsigned long, unsigned long, diff --git a/mm/mmap.c b/mm/mmap.c index 032605bda665..62cb02310494 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2712,12 +2712,9 @@ unsigned long vm_brk(unsigned long addr, unsigned long len) unsigned long ret; bool populate; - /* - * XXX not all users are chcecking the return value, convert - * to down_write_killable after they are able to cope with - * error - */ - down_write(&mm->mmap_sem); + if (down_write_killable(&mm->mmap_sem)) + return -EINTR; + ret = do_brk(addr, len); populate = ((mm->def_flags & VM_LOCKED) != 0); up_write(&mm->mmap_sem); -- 2.8.0.rc3