From patchwork Fri Jun 21 09:52:30 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vincenzo Frascino X-Patchwork-Id: 11009475 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 97EF876 for ; Fri, 21 Jun 2019 09:55:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8499C289E5 for ; Fri, 21 Jun 2019 09:55:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 78B02289EC; Fri, 21 Jun 2019 09:55:11 +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 B472C289E5 for ; Fri, 21 Jun 2019 09:55:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726218AbfFUJxR (ORCPT ); Fri, 21 Jun 2019 05:53:17 -0400 Received: from foss.arm.com ([217.140.110.172]:55188 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726715AbfFUJxQ (ORCPT ); Fri, 21 Jun 2019 05:53:16 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 6226E14F6; Fri, 21 Jun 2019 02:53:15 -0700 (PDT) Received: from e119884-lin.cambridge.arm.com (e119884-lin.cambridge.arm.com [10.1.196.72]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id CCFF13F246; Fri, 21 Jun 2019 02:53:12 -0700 (PDT) From: Vincenzo Frascino To: linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: Catalin Marinas , Will Deacon , Arnd Bergmann , Russell King , Ralf Baechle , Paul Burton , Daniel Lezcano , Thomas Gleixner , Mark Salyzyn , Peter Collingbourne , Shuah Khan , Dmitry Safonov <0x7f454c46@gmail.com>, Rasmus Villemoes , Huw Davies , Shijith Thotton , Andre Przywara Subject: [PATCH v7 03/25] kernel: Unify update_vsyscall implementation Date: Fri, 21 Jun 2019 10:52:30 +0100 Message-Id: <20190621095252.32307-4-vincenzo.frascino@arm.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190621095252.32307-1-vincenzo.frascino@arm.com> References: <20190621095252.32307-1-vincenzo.frascino@arm.com> MIME-Version: 1.0 Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP With the definition of the unified vDSO library the implementations of update_vsyscall and update_vsyscall_tz became quite similar across architectures. Define a unified implementation of these two functions in kernel/vdso and provide the bindings that can be implemented by every architecture that takes advantage of the unified vDSO library. Signed-off-by: Vincenzo Frascino Tested-by: Shijith Thotton Tested-by: Andre Przywara --- include/asm-generic/vdso/vsyscall.h | 56 ++++++++++++ include/linux/timekeeper_internal.h | 9 ++ include/vdso/vsyscall.h | 11 +++ kernel/Makefile | 1 + kernel/vdso/Makefile | 2 + kernel/vdso/vsyscall.c | 131 ++++++++++++++++++++++++++++ 6 files changed, 210 insertions(+) create mode 100644 include/asm-generic/vdso/vsyscall.h create mode 100644 include/vdso/vsyscall.h create mode 100644 kernel/vdso/Makefile create mode 100644 kernel/vdso/vsyscall.c diff --git a/include/asm-generic/vdso/vsyscall.h b/include/asm-generic/vdso/vsyscall.h new file mode 100644 index 000000000000..9a4b9fbcc9b6 --- /dev/null +++ b/include/asm-generic/vdso/vsyscall.h @@ -0,0 +1,56 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ASM_GENERIC_VSYSCALL_H +#define __ASM_GENERIC_VSYSCALL_H + +#ifndef __ASSEMBLY__ + +#ifndef __arch_get_k_vdso_data +static __always_inline +struct vdso_data *__arch_get_k_vdso_data(void) +{ + return NULL; +} +#endif /* __arch_get_k_vdso_data */ + +#ifndef __arch_update_vdso_data +static __always_inline +int __arch_update_vdso_data(void) +{ + return 0; +} +#endif /* __arch_update_vdso_data */ + +#ifndef __arch_get_clock_mode +static __always_inline +int __arch_get_clock_mode(struct timekeeper *tk) +{ + return 0; +} +#endif /* __arch_get_clock_mode */ + +#ifndef __arch_use_vsyscall +static __always_inline +int __arch_use_vsyscall(struct vdso_data *vdata) +{ + return 1; +} +#endif /* __arch_use_vsyscall */ + +#ifndef __arch_update_vsyscall +static __always_inline +void __arch_update_vsyscall(struct vdso_data *vdata, + struct timekeeper *tk) +{ +} +#endif /* __arch_update_vsyscall */ + +#ifndef __arch_sync_vdso_data +static __always_inline +void __arch_sync_vdso_data(struct vdso_data *vdata) +{ +} +#endif /* __arch_sync_vdso_data */ + +#endif /* !__ASSEMBLY__ */ + +#endif /* __ASM_GENERIC_VSYSCALL_H */ diff --git a/include/linux/timekeeper_internal.h b/include/linux/timekeeper_internal.h index 7acb953298a7..8177e75a71eb 100644 --- a/include/linux/timekeeper_internal.h +++ b/include/linux/timekeeper_internal.h @@ -135,9 +135,18 @@ struct timekeeper { #ifdef CONFIG_GENERIC_TIME_VSYSCALL +#ifdef CONFIG_HAVE_GENERIC_VDSO + +void update_vsyscall(struct timekeeper *tk); +void update_vsyscall_tz(void); + +#else + extern void update_vsyscall(struct timekeeper *tk); extern void update_vsyscall_tz(void); +#endif /* CONFIG_HAVE_GENERIC_VDSO */ + #else static inline void update_vsyscall(struct timekeeper *tk) diff --git a/include/vdso/vsyscall.h b/include/vdso/vsyscall.h new file mode 100644 index 000000000000..2c6134e0c23d --- /dev/null +++ b/include/vdso/vsyscall.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __VDSO_VSYSCALL_H +#define __VDSO_VSYSCALL_H + +#ifndef __ASSEMBLY__ + +#include + +#endif /* !__ASSEMBLY__ */ + +#endif /* __VDSO_VSYSCALL_H */ diff --git a/kernel/Makefile b/kernel/Makefile index 33824f0385b3..56a98ebb7772 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -48,6 +48,7 @@ obj-$(CONFIG_CHECKPOINT_RESTORE) += kcmp.o obj-$(CONFIG_FREEZER) += freezer.o obj-$(CONFIG_PROFILING) += profile.o obj-$(CONFIG_STACKTRACE) += stacktrace.o +obj-$(CONFIG_HAVE_GENERIC_VDSO) += vdso/ obj-y += time/ obj-$(CONFIG_FUTEX) += futex.o obj-$(CONFIG_GENERIC_ISA_DMA) += dma.o diff --git a/kernel/vdso/Makefile b/kernel/vdso/Makefile new file mode 100644 index 000000000000..ad0d3b1a475c --- /dev/null +++ b/kernel/vdso/Makefile @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0 +obj-$(CONFIG_HAVE_GENERIC_VDSO) += vsyscall.o diff --git a/kernel/vdso/vsyscall.c b/kernel/vdso/vsyscall.c new file mode 100644 index 000000000000..d1e8074e3d10 --- /dev/null +++ b/kernel/vdso/vsyscall.c @@ -0,0 +1,131 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2019 ARM Ltd. + * + * Generic implementation of update_vsyscall and update_vsyscall_tz. + */ + +#include +#include +#include +#include +#include + +static inline void update_vdso_data(struct vdso_data *vdata, + struct timekeeper *tk) +{ + struct vdso_timestamp *vdso_ts; + u64 nsec; + + vdata[CS_HRES_COARSE].cycle_last = tk->tkr_mono.cycle_last; + vdata[CS_HRES_COARSE].mask = tk->tkr_mono.mask; + vdata[CS_HRES_COARSE].mult = tk->tkr_mono.mult; + vdata[CS_HRES_COARSE].shift = tk->tkr_mono.shift; + vdata[CS_RAW].cycle_last = tk->tkr_raw.cycle_last; + vdata[CS_RAW].mask = tk->tkr_raw.mask; + vdata[CS_RAW].mult = tk->tkr_raw.mult; + vdata[CS_RAW].shift = tk->tkr_raw.shift; + + /* CLOCK_REALTIME */ + vdso_ts = &vdata[CS_HRES_COARSE].basetime[CLOCK_REALTIME]; + vdso_ts->sec = tk->xtime_sec; + vdso_ts->nsec = tk->tkr_mono.xtime_nsec; + + /* CLOCK_MONOTONIC */ + vdso_ts = &vdata[CS_HRES_COARSE].basetime[CLOCK_MONOTONIC]; + vdso_ts->sec = tk->xtime_sec + tk->wall_to_monotonic.tv_sec; + + nsec = tk->tkr_mono.xtime_nsec; + nsec += ((u64)tk->wall_to_monotonic.tv_nsec << tk->tkr_mono.shift); + while (nsec >= (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift)) { + nsec -= (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift); + vdso_ts->sec++; + } + vdso_ts->nsec = nsec; + + /* CLOCK_MONOTONIC_RAW */ + vdso_ts = &vdata[CS_RAW].basetime[CLOCK_MONOTONIC_RAW]; + vdso_ts->sec = tk->raw_sec; + vdso_ts->nsec = tk->tkr_raw.xtime_nsec; + + /* CLOCK_BOOTTIME */ + vdso_ts = &vdata[CS_HRES_COARSE].basetime[CLOCK_BOOTTIME]; + vdso_ts->sec = tk->xtime_sec + tk->wall_to_monotonic.tv_sec; + nsec = tk->tkr_mono.xtime_nsec; + nsec += ((u64)(tk->wall_to_monotonic.tv_nsec + + ktime_to_ns(tk->offs_boot)) << tk->tkr_mono.shift); + while (nsec >= (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift)) { + nsec -= (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift); + vdso_ts->sec++; + } + vdso_ts->nsec = nsec; + + /* CLOCK_TAI */ + vdso_ts = &vdata[CS_HRES_COARSE].basetime[CLOCK_TAI]; + vdso_ts->sec = tk->xtime_sec + (s64)tk->tai_offset; + vdso_ts->nsec = tk->tkr_mono.xtime_nsec; + + /* + * Read without the seqlock held by clock_getres(). + * Note: No need to have a second copy. + */ + WRITE_ONCE(vdata[CS_HRES_COARSE].hrtimer_res, hrtimer_resolution); +} + +void update_vsyscall(struct timekeeper *tk) +{ + struct vdso_data *vdata = __arch_get_k_vdso_data(); + struct vdso_timestamp *vdso_ts; + u64 nsec; + + if (__arch_update_vdso_data()) { + /* + * Some architectures might want to skip the update of the + * data page. + */ + return; + } + + /* copy vsyscall data */ + vdso_write_begin(vdata); + + vdata[CS_HRES_COARSE].clock_mode = __arch_get_clock_mode(tk); + vdata[CS_RAW].clock_mode = __arch_get_clock_mode(tk); + + /* CLOCK_REALTIME_COARSE */ + vdso_ts = &vdata[CS_HRES_COARSE].basetime[CLOCK_REALTIME_COARSE]; + vdso_ts->sec = tk->xtime_sec; + vdso_ts->nsec = tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift; + + /* CLOCK_MONOTONIC_COARSE */ + vdso_ts = &vdata[CS_HRES_COARSE].basetime[CLOCK_MONOTONIC_COARSE]; + vdso_ts->sec = tk->xtime_sec + tk->wall_to_monotonic.tv_sec; + nsec = tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift; + nsec = nsec + tk->wall_to_monotonic.tv_nsec; + while (nsec >= NSEC_PER_SEC) { + nsec = nsec - NSEC_PER_SEC; + vdso_ts->sec++; + } + vdso_ts->nsec = nsec; + + if (__arch_use_vsyscall(vdata)) + update_vdso_data(vdata, tk); + + __arch_update_vsyscall(vdata, tk); + + vdso_write_end(vdata); + + __arch_sync_vdso_data(vdata); +} + +void update_vsyscall_tz(void) +{ + struct vdso_data *vdata = __arch_get_k_vdso_data(); + + if (__arch_use_vsyscall(vdata)) { + vdata[CS_HRES_COARSE].tz_minuteswest = sys_tz.tz_minuteswest; + vdata[CS_HRES_COARSE].tz_dsttime = sys_tz.tz_dsttime; + } + + __arch_sync_vdso_data(vdata); +}