From patchwork Fri Mar 22 07:42:25 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandre Ghiti X-Patchwork-Id: 10865211 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 799646C2 for ; Fri, 22 Mar 2019 07:47:08 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5B92C2A5CE for ; Fri, 22 Mar 2019 07:47:08 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4ED8D2A5D1; Fri, 22 Mar 2019 07:47:08 +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=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id ED9732A5CE for ; Fri, 22 Mar 2019 07:47:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=gdfXPHl95/Hfb4rjEpyysu0OlEuQGHjoRgl093nP8W0=; b=mOCOdCGrpgWNoL XEeB1W+pWOiY6Rm/gcaDAE9p7kDgpfuve6wcbLrcXNgcovowzCDNsOm4ZgzthdqOKntojl2umAgz6 F071tGScsXo5OS4DFfjcdCGRjBDqXngR8wzRwuRC96Tp6rKXnX9M8uUXoGnx0N4otDJeGmyhFYLb+ El1Bkeyupb4TSp7OdTcZwctmgYugX1E3m6ABe3fVqjEZDfnVV2NQDTQzgj7DBn6EATj+E1eyyQ217 rakvJpmvNAbnWM59IslRatz+DRmn+JeI3hIOT6bTXN19e8+VQSSw2J7pqxgZFYIL/y/akCnBGajvk BgmwHc9sb1Gt5YdfPkug==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h7EtM-0007Ki-60; Fri, 22 Mar 2019 07:47:04 +0000 Received: from relay12.mail.gandi.net ([217.70.178.232]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1h7EtB-0007B4-Lp; Fri, 22 Mar 2019 07:46:56 +0000 Received: from alex.numericable.fr (127.19.86.79.rev.sfr.net [79.86.19.127]) (Authenticated sender: alex@ghiti.fr) by relay12.mail.gandi.net (Postfix) with ESMTPSA id EECA9200009; Fri, 22 Mar 2019 07:46:47 +0000 (UTC) From: Alexandre Ghiti To: 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 Subject: [PATCH 4/4] riscv: Make mmap allocation top-down by default Date: Fri, 22 Mar 2019 03:42:25 -0400 Message-Id: <20190322074225.22282-5-alex@ghiti.fr> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190322074225.22282-1-alex@ghiti.fr> References: <20190322074225.22282-1-alex@ghiti.fr> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190322_004655_388813_AC143EED X-CRM114-Status: UNSURE ( 7.79 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Alexandre Ghiti Sender: "linux-riscv" Errors-To: linux-riscv-bounces+patchwork-linux-riscv=patchwork.kernel.org@lists.infradead.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 --- arch/riscv/Kconfig | 12 ++++++++++++ arch/riscv/include/asm/processor.h | 1 + 2 files changed, 13 insertions(+) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index eb56c82d8aa1..7661335d1667 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -50,6 +50,18 @@ config RISCV select ARCH_HAS_PTE_SPECIAL select HAVE_EBPF_JIT if 64BIT +config HAVE_ARCH_MMAP_RND_BITS + def_bool y + +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 diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h index ce70bceb8872..e68a1b1e144a 100644 --- a/arch/riscv/include/asm/processor.h +++ b/arch/riscv/include/asm/processor.h @@ -23,6 +23,7 @@ * space during mmap's. */ #define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3) +#define ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT #define STACK_TOP TASK_SIZE #define STACK_TOP_MAX STACK_TOP