srcu: Move rcu_scheduler_starting() from Tiny RCU to Tiny SRCU (825c5bd2) · Commits · 戴 / test

include/linux/rcupdate.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -105,6 +105,7 @@ static inline int rcu_preempt_depth(void)

		/* Internal to kernel */
		void rcu_init(void);
		extern int rcu_scheduler_active __read_mostly;
		void rcu_sched_qs(void);
		void rcu_bh_qs(void);
		void rcu_check_callbacks(int user);

include/linux/rcutiny.h

+3 −5

Original line number	Diff line number	Diff line
		@@ -116,13 +116,11 @@ static inline void rcu_irq_exit_irqson(void) { }
		static inline void rcu_irq_enter_irqson(void) { }
		static inline void rcu_irq_exit(void) { }
		static inline void exit_rcu(void) { }

		#if defined(CONFIG_DEBUG_LOCK_ALLOC) \|\| defined(CONFIG_SRCU)
		extern int rcu_scheduler_active __read_mostly;
		#ifdef CONFIG_SRCU
		void rcu_scheduler_starting(void);
		#else /* #if defined(CONFIG_DEBUG_LOCK_ALLOC) \|\| defined(CONFIG_SRCU) */
		#else /* #ifndef CONFIG_SRCU */
		static inline void rcu_scheduler_starting(void) { }
		#endif /* #else #if defined(CONFIG_DEBUG_LOCK_ALLOC) \|\| defined(CONFIG_SRCU) */
		#endif /* #else #ifndef CONFIG_SRCU */
		static inline void rcu_end_inkernel_boot(void) { }
		static inline bool rcu_is_watching(void) { return true; }

kernel/rcu/srcutiny.c

+8 −0

Original line number	Diff line number	Diff line
		@@ -33,6 +33,8 @@
		#include "rcu_segcblist.h"
		#include "rcu.h"

		int rcu_scheduler_active __read_mostly;

		static int init_srcu_struct_fields(struct srcu_struct *sp)
		{
		sp->srcu_lock_nesting[0] = 0;
		@@ -193,3 +195,9 @@ void synchronize_srcu(struct srcu_struct *sp)
		destroy_rcu_head_on_stack(&rs.head);
		}
		EXPORT_SYMBOL_GPL(synchronize_srcu);

		/* Lockdep diagnostics. */
		void __init rcu_scheduler_starting(void)
		{
		rcu_scheduler_active = RCU_SCHEDULER_RUNNING;
		}

kernel/rcu/tiny.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -56,8 +56,6 @@ static struct rcu_ctrlblk rcu_bh_ctrlblk = {
		.curtail = &rcu_bh_ctrlblk.rcucblist,
		};

		#include "tiny_plugin.h"

		void rcu_barrier_bh(void)
		{
		wait_rcu_gp(call_rcu_bh);

kernel/rcu/tiny_plugin.h

deleted100644 → 0

+0 −47

Original line number	Diff line number	Diff line
		/*
		* Read-Copy Update mechanism for mutual exclusion, the Bloatwatch edition
		* Internal non-public definitions that provide either classic
		* or preemptible semantics.
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License as published by
		* the Free Software Foundation; either version 2 of the License, or
		* (at your option) any later version.
		*
		* 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, you can access it online at
		* http://www.gnu.org/licenses/gpl-2.0.html.
		*
		* Copyright (c) 2010 Linaro
		*
		* Author: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
		*/

		#if defined(CONFIG_DEBUG_LOCK_ALLOC) \|\| defined(CONFIG_SRCU)
		#include <linux/kernel_stat.h>

		int rcu_scheduler_active __read_mostly;
		EXPORT_SYMBOL_GPL(rcu_scheduler_active);

		/*
		* During boot, we forgive RCU lockdep issues. After this function is
		* invoked, we start taking RCU lockdep issues seriously. Note that unlike
		* Tree RCU, Tiny RCU transitions directly from RCU_SCHEDULER_INACTIVE
		* to RCU_SCHEDULER_RUNNING, skipping the RCU_SCHEDULER_INIT stage.
		* The reason for this is that Tiny RCU does not need kthreads, so does
		* not have to care about the fact that the scheduler is half-initialized
		* at a certain phase of the boot process. Unless SRCU is in the mix.
		*/
		void __init rcu_scheduler_starting(void)
		{
		WARN_ON(nr_context_switches() > 0);
		rcu_scheduler_active = IS_ENABLED(CONFIG_SRCU)
		? RCU_SCHEDULER_INIT : RCU_SCHEDULER_RUNNING;
		}

		#endif /* #if defined(CONFIG_DEBUG_LOCK_ALLOC) \|\| defined(CONFIG_SRCU) */

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