From 01573e231f18eb2d99162747186f59511f56b64d Mon Sep 17 00:00:00 2001 From: hc <hc@nodka.com> Date: Fri, 08 Dec 2023 10:40:48 +0000 Subject: [PATCH] 移去rt --- kernel/arch/arm/kernel/vdso.c | 103 +++------------------------------------------------ 1 files changed, 7 insertions(+), 96 deletions(-) diff --git a/kernel/arch/arm/kernel/vdso.c b/kernel/arch/arm/kernel/vdso.c index a51b7ff..fddd08a 100644 --- a/kernel/arch/arm/kernel/vdso.c +++ b/kernel/arch/arm/kernel/vdso.c @@ -1,20 +1,9 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Adapted from arm64 version. * * Copyright (C) 2012 ARM Limited * Copyright (C) 2015 Mentor Graphics Corporation. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include <linux/cache.h> @@ -34,6 +23,8 @@ #include <asm/vdso.h> #include <asm/vdso_datapage.h> #include <clocksource/arm_arch_timer.h> +#include <vdso/helpers.h> +#include <vdso/vsyscall.h> #define MAX_SYMNAME 64 @@ -48,7 +39,7 @@ * The VDSO data page. */ static union vdso_data_store vdso_data_store __page_aligned_data; -static struct vdso_data *vdso_data = &vdso_data_store.data; +struct vdso_data *vdso_data = vdso_data_store.data; static struct page *vdso_data_page __ro_after_init; static const struct vm_special_mapping vdso_data_mapping = { @@ -88,7 +79,7 @@ /* Cached result of boot-time check for whether the arch timer exists, * and if so, whether the virtual counter is useable. */ -static bool cntvct_ok __ro_after_init; +bool cntvct_ok __ro_after_init; static bool __init cntvct_functional(void) { @@ -193,6 +184,7 @@ if (!cntvct_ok) { vdso_nullpatch_one(&einfo, "__vdso_gettimeofday"); vdso_nullpatch_one(&einfo, "__vdso_clock_gettime"); + vdso_nullpatch_one(&einfo, "__vdso_clock_gettime64"); } } @@ -249,7 +241,7 @@ return PTR_ERR_OR_ZERO(vma); } -/* assumes mmap_sem is write-locked */ +/* assumes mmap_lock is write-locked */ void arm_install_vdso(struct mm_struct *mm, unsigned long addr) { struct vm_area_struct *vma; @@ -275,84 +267,3 @@ mm->context.vdso = addr; } -static void vdso_write_begin(struct vdso_data *vdata) -{ - ++vdso_data->seq_count; - smp_wmb(); /* Pairs with smp_rmb in vdso_read_retry */ -} - -static void vdso_write_end(struct vdso_data *vdata) -{ - smp_wmb(); /* Pairs with smp_rmb in vdso_read_begin */ - ++vdso_data->seq_count; -} - -static bool tk_is_cntvct(const struct timekeeper *tk) -{ - if (!IS_ENABLED(CONFIG_ARM_ARCH_TIMER)) - return false; - - if (!tk->tkr_mono.clock->archdata.vdso_direct) - return false; - - return true; -} - -/** - * update_vsyscall - update the vdso data page - * - * Increment the sequence counter, making it odd, indicating to - * userspace that an update is in progress. Update the fields used - * for coarse clocks and, if the architected system timer is in use, - * the fields used for high precision clocks. Increment the sequence - * counter again, making it even, indicating to userspace that the - * update is finished. - * - * Userspace is expected to sample seq_count before reading any other - * fields from the data page. If seq_count is odd, userspace is - * expected to wait until it becomes even. After copying data from - * the page, userspace must sample seq_count again; if it has changed - * from its previous value, userspace must retry the whole sequence. - * - * Calls to update_vsyscall are serialized by the timekeeping core. - */ -void update_vsyscall(struct timekeeper *tk) -{ - struct timespec64 *wtm = &tk->wall_to_monotonic; - - if (!cntvct_ok) { - /* The entry points have been zeroed, so there is no - * point in updating the data page. - */ - return; - } - - vdso_write_begin(vdso_data); - - vdso_data->tk_is_cntvct = tk_is_cntvct(tk); - vdso_data->xtime_coarse_sec = tk->xtime_sec; - vdso_data->xtime_coarse_nsec = (u32)(tk->tkr_mono.xtime_nsec >> - tk->tkr_mono.shift); - vdso_data->wtm_clock_sec = wtm->tv_sec; - vdso_data->wtm_clock_nsec = wtm->tv_nsec; - - if (vdso_data->tk_is_cntvct) { - vdso_data->cs_cycle_last = tk->tkr_mono.cycle_last; - vdso_data->xtime_clock_sec = tk->xtime_sec; - vdso_data->xtime_clock_snsec = tk->tkr_mono.xtime_nsec; - vdso_data->cs_mult = tk->tkr_mono.mult; - vdso_data->cs_shift = tk->tkr_mono.shift; - vdso_data->cs_mask = tk->tkr_mono.mask; - } - - vdso_write_end(vdso_data); - - flush_dcache_page(virt_to_page(vdso_data)); -} - -void update_vsyscall_tz(void) -{ - vdso_data->tz_minuteswest = sys_tz.tz_minuteswest; - vdso_data->tz_dsttime = sys_tz.tz_dsttime; - flush_dcache_page(virt_to_page(vdso_data)); -} -- Gitblit v1.6.2