From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mslow2.mail.gandi.net ([217.70.178.242]:46776 "EHLO mslow2.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725871AbfFTGDF (ORCPT ); Thu, 20 Jun 2019 02:03:05 -0400 From: Alexandre Ghiti Subject: [PATCH RESEND 4/8] x86, hugetlbpage: Start fallback of top-down mmap at mm->mmap_base Date: Thu, 20 Jun 2019 01:03:24 -0400 Message-Id: <20190620050328.8942-5-alex@ghiti.fr> In-Reply-To: <20190620050328.8942-1-alex@ghiti.fr> References: <20190620050328.8942-1-alex@ghiti.fr> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-s390-owner@vger.kernel.org List-ID: To: Andrew Morton Cc: "James E . J . Bottomley" , Helge Deller , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Yoshinori Sato , Rich Felker , "David S . Miller" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H . Peter Anvin" , x86@kernel.org, Dave Hansen , Andy Lutomirski , Peter Zijlstra , linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-mm@kvack.org, Alexandre Ghiti In case of mmap failure in top-down mode, there is no need to go through the whole address space again for the bottom-up fallback: the goal of this fallback is to find, as a last resort, space between the top-down mmap base and the stack, which is the only place not covered by the top-down mmap. Signed-off-by: Alexandre Ghiti --- arch/x86/mm/hugetlbpage.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c index fab095362c50..4b90339aef50 100644 --- a/arch/x86/mm/hugetlbpage.c +++ b/arch/x86/mm/hugetlbpage.c @@ -106,11 +106,12 @@ static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file, { struct hstate *h = hstate_file(file); struct vm_unmapped_area_info info; + unsigned long mmap_base = get_mmap_base(0); info.flags = VM_UNMAPPED_AREA_TOPDOWN; info.length = len; info.low_limit = PAGE_SIZE; - info.high_limit = get_mmap_base(0); + info.high_limit = mmap_base; /* * If hint address is above DEFAULT_MAP_WINDOW, look for unmapped area @@ -132,7 +133,7 @@ static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file, if (addr & ~PAGE_MASK) { VM_BUG_ON(addr != -ENOMEM); info.flags = 0; - info.low_limit = TASK_UNMAPPED_BASE; + info.low_limit = mmap_base; info.high_limit = TASK_SIZE_LOW; addr = vm_unmapped_area(&info); } -- 2.20.1