From patchwork Thu Apr 4 05:51:28 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandre Ghiti X-Patchwork-Id: 10885011 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0A73F1708 for ; Thu, 4 Apr 2019 05:57:09 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EAE7A28A1F for ; Thu, 4 Apr 2019 05:57:08 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id DE0D328A22; Thu, 4 Apr 2019 05:57:08 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 78D8F28A1F for ; Thu, 4 Apr 2019 05:57:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725927AbfDDF5H (ORCPT ); Thu, 4 Apr 2019 01:57:07 -0400 Received: from relay7-d.mail.gandi.net ([217.70.183.200]:57879 "EHLO relay7-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725914AbfDDF5H (ORCPT ); Thu, 4 Apr 2019 01:57:07 -0400 X-Originating-IP: 79.86.19.127 Received: from alex.numericable.fr (127.19.86.79.rev.sfr.net [79.86.19.127]) (Authenticated sender: alex@ghiti.fr) by relay7-d.mail.gandi.net (Postfix) with ESMTPSA id 144E02000D; Thu, 4 Apr 2019 05:56:59 +0000 (UTC) From: Alexandre Ghiti To: Andrew Morton Cc: Christoph Hellwig , Russell King , Catalin Marinas , Will Deacon , Ralf Baechle , Paul Burton , James Hogan , Palmer Dabbelt , Albert Ou , Alexander Viro , Luis Chamberlain , Kees Cook , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, linux-riscv@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Alexandre Ghiti Subject: [PATCH v2 5/5] riscv: Make mmap allocation top-down by default Date: Thu, 4 Apr 2019 01:51:28 -0400 Message-Id: <20190404055128.24330-6-alex@ghiti.fr> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190404055128.24330-1-alex@ghiti.fr> References: <20190404055128.24330-1-alex@ghiti.fr> MIME-Version: 1.0 Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In order to avoid wasting user address space by using bottom-up mmap allocation scheme, prefer top-down scheme when possible. Before: root@qemuriscv64:~# cat /proc/self/maps 00010000-00016000 r-xp 00000000 fe:00 6389 /bin/cat.coreutils 00016000-00017000 r--p 00005000 fe:00 6389 /bin/cat.coreutils 00017000-00018000 rw-p 00006000 fe:00 6389 /bin/cat.coreutils 00018000-00039000 rw-p 00000000 00:00 0 [heap] 1555556000-155556d000 r-xp 00000000 fe:00 7193 /lib/ld-2.28.so 155556d000-155556e000 r--p 00016000 fe:00 7193 /lib/ld-2.28.so 155556e000-155556f000 rw-p 00017000 fe:00 7193 /lib/ld-2.28.so 155556f000-1555570000 rw-p 00000000 00:00 0 1555570000-1555572000 r-xp 00000000 00:00 0 [vdso] 1555574000-1555576000 rw-p 00000000 00:00 0 1555576000-1555674000 r-xp 00000000 fe:00 7187 /lib/libc-2.28.so 1555674000-1555678000 r--p 000fd000 fe:00 7187 /lib/libc-2.28.so 1555678000-155567a000 rw-p 00101000 fe:00 7187 /lib/libc-2.28.so 155567a000-15556a0000 rw-p 00000000 00:00 0 3fffb90000-3fffbb1000 rw-p 00000000 00:00 0 [stack] After: root@qemuriscv64:~# cat /proc/self/maps 00010000-00016000 r-xp 00000000 fe:00 6389 /bin/cat.coreutils 00016000-00017000 r--p 00005000 fe:00 6389 /bin/cat.coreutils 00017000-00018000 rw-p 00006000 fe:00 6389 /bin/cat.coreutils 00018000-00039000 rw-p 00000000 00:00 0 [heap] 3ff7eb6000-3ff7ed8000 rw-p 00000000 00:00 0 3ff7ed8000-3ff7fd6000 r-xp 00000000 fe:00 7187 /lib/libc-2.28.so 3ff7fd6000-3ff7fda000 r--p 000fd000 fe:00 7187 /lib/libc-2.28.so 3ff7fda000-3ff7fdc000 rw-p 00101000 fe:00 7187 /lib/libc-2.28.so 3ff7fdc000-3ff7fe2000 rw-p 00000000 00:00 0 3ff7fe4000-3ff7fe6000 r-xp 00000000 00:00 0 [vdso] 3ff7fe6000-3ff7ffd000 r-xp 00000000 fe:00 7193 /lib/ld-2.28.so 3ff7ffd000-3ff7ffe000 r--p 00016000 fe:00 7193 /lib/ld-2.28.so 3ff7ffe000-3ff7fff000 rw-p 00017000 fe:00 7193 /lib/ld-2.28.so 3ff7fff000-3ff8000000 rw-p 00000000 00:00 0 3fff888000-3fff8a9000 rw-p 00000000 00:00 0 [stack] Signed-off-by: Alexandre Ghiti Reviewed-by: Christoph Hellwig --- arch/riscv/Kconfig | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index eb56c82d8aa1..fe09f38ef9a9 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -49,6 +49,17 @@ config RISCV select GENERIC_IRQ_MULTI_HANDLER select ARCH_HAS_PTE_SPECIAL select HAVE_EBPF_JIT if 64BIT + select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT + select HAVE_ARCH_MMAP_RND_BITS + +config ARCH_MMAP_RND_BITS_MIN + default 18 + +# max bits determined by the following formula: +# VA_BITS - PAGE_SHIFT - 3 +config ARCH_MMAP_RND_BITS_MAX + default 33 if 64BIT # SV48 based + default 18 config MMU def_bool y