From patchwork Mon Jan 13 17:08:46 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christophe Leroy X-Patchwork-Id: 11330597 X-Patchwork-Delegate: paulburton@kernel.org 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 957F992A for ; Mon, 13 Jan 2020 17:09:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 74637222C3 for ; Mon, 13 Jan 2020 17:09:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=c-s.fr header.i=@c-s.fr header.b="QXDttb7T" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728946AbgAMRJR (ORCPT ); Mon, 13 Jan 2020 12:09:17 -0500 Received: from pegase1.c-s.fr ([93.17.236.30]:44559 "EHLO pegase1.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728813AbgAMRIt (ORCPT ); Mon, 13 Jan 2020 12:08:49 -0500 Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 47xKmp0qNrz9tyXm; Mon, 13 Jan 2020 18:08:42 +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=QXDttb7T; 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 Mc_QosJO-mW7; Mon, 13 Jan 2020 18:08:42 +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 47xKmn6v83z9tyXf; Mon, 13 Jan 2020 18:08:41 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=c-s.fr; s=mail; t=1578935322; bh=JanAVwbfNrKMTHQ/SPAcOrXRwMktvfccR82GG0SlEYo=; h=In-Reply-To:References:From:Subject:To:Cc:Date:From; b=QXDttb7ToEKfY2gd8XNY7XB93hxx/aeTMiIVlXLs/0Y83dLW1ty70gGR5EWJQ+cJt J0Hmeex0AZuZDUOzTs9PzDmQ77FGZDp3DoRG06cEavNftLwvWtFUmiA3SGHkK4LJrz tUQ3nMsAQorHOQj2uWGEk5C4cVX+0To9zf2SzZjY= Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 4909C8B7C9; Mon, 13 Jan 2020 18:08:47 +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 9c-CErJ1jcq7; Mon, 13 Jan 2020 18:08:47 +0100 (CET) Received: from po14934vm.idsi0.si.c-s.fr (unknown [192.168.4.90]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 00EC78B7BE; Mon, 13 Jan 2020 18:08:46 +0100 (CET) Received: by localhost.localdomain (Postfix, from userid 0) id C95E864A1D; Mon, 13 Jan 2020 17:08:46 +0000 (UTC) Message-Id: <381e547dbb3c48fd39d6cf208033bba38ad048fb.1578934751.git.christophe.leroy@c-s.fr> In-Reply-To: References: From: Christophe Leroy Subject: [RFC PATCH v3 08/12] lib: vdso: allow arches to provide vdso data pointer To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , arnd@arndb.de, tglx@linutronix.de, vincenzo.frascino@arm.com, luto@kernel.org Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org, x86@kernel.org Date: Mon, 13 Jan 2020 17:08:46 +0000 (UTC) Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org On powerpc, __arch_get_vdso_data() clobbers the link register, requiring the caller to save it. As the parent function already has to set a stack frame and saves the link register before calling the C vdso function, retriving the vdso data pointer there is lighter. Give arches the opportunity to hand the vdso data pointer to C vdso functions. Signed-off-by: Christophe Leroy --- lib/vdso/gettimeofday.c | 56 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) diff --git a/lib/vdso/gettimeofday.c b/lib/vdso/gettimeofday.c index da15a8842825..ea1a55507af5 100644 --- a/lib/vdso/gettimeofday.c +++ b/lib/vdso/gettimeofday.c @@ -104,9 +104,15 @@ static __always_inline int do_coarse(const struct vdso_data *vd, clockid_t clk, } static __maybe_unused int +#ifdef VDSO_GETS_VD_PTR_FROM_ARCH +__cvdso_clock_gettime_common(const struct vdso_data *vd, clockid_t clock, + struct __kernel_timespec *ts) +{ +#else __cvdso_clock_gettime_common(clockid_t clock, struct __kernel_timespec *ts) { const struct vdso_data *vd = __arch_get_vdso_data(); +#endif u32 msk; /* Check for negative values or invalid clocks */ @@ -131,9 +137,16 @@ __cvdso_clock_gettime_common(clockid_t clock, struct __kernel_timespec *ts) } static __maybe_unused int +#ifdef VDSO_GETS_VD_PTR_FROM_ARCH +__cvdso_clock_gettime(const struct vdso_data *vd, clockid_t clock, + struct __kernel_timespec *ts) +{ + int ret = __cvdso_clock_gettime_common(vd, clock, ts); +#else __cvdso_clock_gettime(clockid_t clock, struct __kernel_timespec *ts) { int ret = __cvdso_clock_gettime_common(clock, ts); +#endif if (unlikely(ret)) return clock_gettime_fallback(clock, ts); @@ -141,12 +154,21 @@ __cvdso_clock_gettime(clockid_t clock, struct __kernel_timespec *ts) } static __maybe_unused int +#ifdef VDSO_GETS_VD_PTR_FROM_ARCH +__cvdso_clock_gettime32(const struct vdso_data *vd, clockid_t clock, + struct old_timespec32 *res) +#else __cvdso_clock_gettime32(clockid_t clock, struct old_timespec32 *res) +#endif { struct __kernel_timespec ts; int ret; +#ifdef VDSO_GETS_VD_PTR_FROM_ARCH + ret = __cvdso_clock_gettime_common(vd, clock, &ts); +#else ret = __cvdso_clock_gettime_common(clock, &ts); +#endif #ifdef VDSO_HAS_32BIT_FALLBACK if (unlikely(ret)) @@ -164,9 +186,15 @@ __cvdso_clock_gettime32(clockid_t clock, struct old_timespec32 *res) } static __maybe_unused int +#ifdef VDSO_GETS_VD_PTR_FROM_ARCH +__cvdso_gettimeofday(const struct vdso_data *vd, struct __kernel_old_timeval *tv, + struct timezone *tz) +{ +#else __cvdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz) { const struct vdso_data *vd = __arch_get_vdso_data(); +#endif if (likely(tv != NULL)) { struct __kernel_timespec ts; @@ -187,9 +215,15 @@ __cvdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz) } #ifdef VDSO_HAS_TIME +#ifdef VDSO_GETS_VD_PTR_FROM_ARCH +static __maybe_unused __kernel_old_time_t +__cvdso_time(const struct vdso_data *vd, __kernel_old_time_t *time) +{ +#else static __maybe_unused __kernel_old_time_t __cvdso_time(__kernel_old_time_t *time) { const struct vdso_data *vd = __arch_get_vdso_data(); +#endif __kernel_old_time_t t = READ_ONCE(vd[CS_HRES_COARSE].basetime[CLOCK_REALTIME].sec); if (time) @@ -201,9 +235,15 @@ static __maybe_unused __kernel_old_time_t __cvdso_time(__kernel_old_time_t *time #ifdef VDSO_HAS_CLOCK_GETRES static __maybe_unused +#ifdef VDSO_GETS_VD_PTR_FROM_ARCH +int __cvdso_clock_getres_common(const struct vdso_data *vd, clockid_t clock, + struct __kernel_timespec *res) +{ +#else int __cvdso_clock_getres_common(clockid_t clock, struct __kernel_timespec *res) { const struct vdso_data *vd = __arch_get_vdso_data(); +#endif u32 msk; u64 ns; @@ -238,9 +278,16 @@ int __cvdso_clock_getres_common(clockid_t clock, struct __kernel_timespec *res) } static __maybe_unused +#ifdef VDSO_GETS_VD_PTR_FROM_ARCH +int __cvdso_clock_getres(const struct vdso_data *vd, clockid_t clock, + struct __kernel_timespec *res) +{ + int ret = __cvdso_clock_getres_common(vd, clock, res); +#else int __cvdso_clock_getres(clockid_t clock, struct __kernel_timespec *res) { int ret = __cvdso_clock_getres_common(clock, res); +#endif if (unlikely(ret)) return clock_getres_fallback(clock, res); @@ -248,12 +295,21 @@ int __cvdso_clock_getres(clockid_t clock, struct __kernel_timespec *res) } static __maybe_unused int +#ifdef VDSO_GETS_VD_PTR_FROM_ARCH +__cvdso_clock_getres_time32(const struct vdso_data *vd, clockid_t clock, + struct old_timespec32 *res) +#else __cvdso_clock_getres_time32(clockid_t clock, struct old_timespec32 *res) +#endif { struct __kernel_timespec ts; int ret; +#ifdef VDSO_GETS_VD_PTR_FROM_ARCH + ret = __cvdso_clock_getres_common(vd, clock, &ts); +#else ret = __cvdso_clock_getres_common(clock, &ts); +#endif #ifdef VDSO_HAS_32BIT_FALLBACK if (unlikely(ret))