From patchwork Mon Dec 23 14:31:01 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christophe Leroy X-Patchwork-Id: 11308411 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D05D9138D for ; Mon, 23 Dec 2019 14:32:09 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id AD70920715 for ; Mon, 23 Dec 2019 14:32:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="kVkX1Bhg"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=c-s.fr header.i=@c-s.fr header.b="cfApg9sH" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AD70920715 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=c-s.fr Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org 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:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:Date:To:Subject: From:Message-Id:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To: References:List-Owner; bh=N29oiLSf884NqGyRSdql0sYQYXsqPUaDrhzjiuRZ4lk=; b=kVk X1BhgN+YA5ZH5CWvF88YRjLMXGEl0V5dGreXh1mHBXyg9LjYPcqLbKG1SB0u3x8dlp5E7bLO9rZXG mLO97ulfIDmSVamU1RnzxlId+vTtOb2QVzyULPuBufTOKlZPoia6B0mnl4Bmw4MwuXU2KXEn0obho q7r/8giH7JsK8XWZoAPgYDpm8lRwBt9T/3Nmjsy+AgIe/vlL3kmByaWDKtNofQJoKYEXPIzhXOG8C xWC3Q5aLhLvJHCI4oXuuEnFI/gNbzfX96zNscPbf4yjoTT98lFTBaQIO+kFdyp5MKvQCDJrbYFoEi KNzPzBm7+DyiS2Vof6GXhkHjjyu+UQw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1ijOki-0001W5-AE; Mon, 23 Dec 2019 14:32:08 +0000 Received: from pegase1.c-s.fr ([93.17.236.30]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1ijOjn-0000k7-Qm for linux-arm-kernel@lists.infradead.org; Mon, 23 Dec 2019 14:31:13 +0000 Received: from localhost (mailhub1-ext [192.168.12.233]) by localhost (Postfix) with ESMTP id 47hMGS5T4sz9txjw; Mon, 23 Dec 2019 15:30:56 +0100 (CET) Authentication-Results: localhost; dkim=pass reason="1024-bit key; insecure key" header.d=c-s.fr header.i=@c-s.fr header.b=cfApg9sH; dkim-adsp=pass; dkim-atps=neutral X-Virus-Scanned: Debian amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [192.168.12.234]) (amavisd-new, port 10024) with ESMTP id NGVhIXcP7bQ8; Mon, 23 Dec 2019 15:30:56 +0100 (CET) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase1.c-s.fr (Postfix) with ESMTP id 47hMGS4B7Wz9txjv; Mon, 23 Dec 2019 15:30:56 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=c-s.fr; s=mail; t=1577111456; bh=yVxuGmQR051J6pETL5q29uPkTsP81kEW/OmeuvlbY/k=; h=From:Subject:To:Cc:Date:From; b=cfApg9sH1a9HHa55YFyf8L755JhqvakH05NG+R/qHkWzE5LUPrg24rswTt4CXyRyC 2bhyW8BcRvrp/qnckgOME1s7wI6VFu8a2RSUlLqOrq/21c00ILlXV1sAzj+xe5fgf+ 5bND3VhxVxgMSsmr0NGgo6eGrLt7/vsuVuvx9Kh4= Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id AD3658B7AB; Mon, 23 Dec 2019 15:31:01 +0100 (CET) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id AbT8jpQZojIw; Mon, 23 Dec 2019 15:31:01 +0100 (CET) Received: from po16098vm.idsi0.si.c-s.fr (po15451.idsi0.si.c-s.fr [172.25.230.100]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 7C04C8B7A1; Mon, 23 Dec 2019 15:31:01 +0100 (CET) Received: by po16098vm.idsi0.si.c-s.fr (Postfix, from userid 0) id 57F2B637D4; Mon, 23 Dec 2019 14:31:01 +0000 (UTC) Message-Id: From: Christophe Leroy Subject: [RFC PATCH v2 00/10] powerpc/32: switch VDSO to C implementation. To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , arnd@arndb.de, tglx@linutronix.de, vincenzo.frascino@arm.com, luto@kernel.org Date: Mon, 23 Dec 2019 14:31:01 +0000 (UTC) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191223_063112_161879_FB1F7B6B X-CRM114-Status: GOOD ( 10.84 ) X-Spam-Score: -0.2 (/) X-Spam-Report: SpamAssassin version 3.4.2 on bombadil.infradead.org summary: Content analysis details: (-0.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at https://www.dnswl.org/, no trust [93.17.236.30 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: x86@kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org This is a second tentative to switch powerpc/32 vdso to generic C implementation. It will likely not work on 64 bits or even build properly at the moment. powerpc is a bit special for VDSO as well as system calls in the way that it requires setting CR SO bit which cannot be done in C. Therefore, entry/exit and fallback needs to be performed in ASM. To allow that, the fallback calls are moved out of the common code and left to the arches. A few other changes in the common code have allowed performance improvement. The performance has improved since first RFC, but it is still lower than current assembly VDSO. On a powerpc8xx, with current powerpc/32 ASM VDSO: gettimeofday: vdso: 737 nsec/call clock-getres-realtime: vdso: 475 nsec/call clock-gettime-realtime: vdso: 892 nsec/call clock-getres-monotonic: vdso: 475 nsec/call clock-gettime-monotonic: vdso: 1014 nsec/call First try of C implementation: gettimeofday: vdso: 1533 nsec/call clock-getres-realtime: vdso: 853 nsec/call clock-gettime-realtime: vdso: 1570 nsec/call clock-getres-monotonic: vdso: 835 nsec/call clock-gettime-monotonic: vdso: 1605 nsec/call With this series: gettimeofday: vdso: 1016 nsec/call clock-getres-realtime: vdso: 560 nsec/call clock-gettime-realtime: vdso: 1192 nsec/call clock-getres-monotonic: vdso: 560 nsec/call clock-gettime-monotonic: vdso: 1192 nsec/call Changes made to other arches are untested, not even compiled. Christophe Leroy (10): lib: vdso: ensure all arches have 32bit fallback lib: vdso: move call to fallback out of common code. lib: vdso: Change __cvdso_clock_gettime/getres_common() to __cvdso_clock_gettime/getres() lib: vdso: get pointer to vdso data from the arch lib: vdso: inline do_hres() lib: vdso: make do_coarse() return 0 lib: vdso: don't use READ_ONCE() in __c_kernel_time() lib: vdso: Avoid duplication in __cvdso_clock_getres() powerpc/vdso32: inline __get_datapage() powerpc/32: Switch VDSO to C implementation. arch/arm/include/asm/vdso/gettimeofday.h | 26 +++ arch/arm/vdso/vgettimeofday.c | 32 ++- arch/arm64/include/asm/vdso/compat_gettimeofday.h | 2 - arch/arm64/include/asm/vdso/gettimeofday.h | 26 +++ arch/arm64/kernel/vdso/vgettimeofday.c | 24 +- arch/arm64/kernel/vdso32/vgettimeofday.c | 39 +++- arch/mips/include/asm/vdso/gettimeofday.h | 28 ++- arch/mips/vdso/vgettimeofday.c | 56 ++++- arch/powerpc/Kconfig | 2 + arch/powerpc/include/asm/vdso/gettimeofday.h | 45 ++++ arch/powerpc/include/asm/vdso/vsyscall.h | 27 +++ arch/powerpc/include/asm/vdso_datapage.h | 28 +-- arch/powerpc/kernel/asm-offsets.c | 23 +- arch/powerpc/kernel/time.c | 92 +------- arch/powerpc/kernel/vdso.c | 19 +- arch/powerpc/kernel/vdso32/Makefile | 19 +- arch/powerpc/kernel/vdso32/cacheflush.S | 9 +- arch/powerpc/kernel/vdso32/datapage.S | 28 +-- arch/powerpc/kernel/vdso32/gettimeofday.S | 265 +++------------------- arch/powerpc/kernel/vdso32/vgettimeofday.c | 32 +++ arch/x86/entry/vdso/vclock_gettime.c | 52 ++++- arch/x86/include/asm/vdso/gettimeofday.h | 28 ++- lib/vdso/gettimeofday.c | 100 +++----- 23 files changed, 505 insertions(+), 497 deletions(-) create mode 100644 arch/powerpc/include/asm/vdso/gettimeofday.h create mode 100644 arch/powerpc/include/asm/vdso/vsyscall.h create mode 100644 arch/powerpc/kernel/vdso32/vgettimeofday.c