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![Paul E. McKenney](/assets/img/avatar_default.png)
Some larger systems can take in excess of 50 seconds to complete their early boot initcalls prior to spawing init. This does not in any way help the forward-progress judgments of built-in rcutorture (when rcutorture is built as a module, the insmod or modprobe command normally cannot happen until some time after boot completes). This commit therefore suppresses such complaints until about the time that init is spawned. This also includes a fix to a stupid error located by kbuild test robot. [ paulmck: Apply kbuild test robot feedback. ] Signed-off-by: Paul E. McKenney <paulmck@kernel.org> [ paulmck: Fix to nohz_full slow-expediting recovery logic, per bpetkov. ] [ paulmck: Restrict splat to CONFIG_PREEMPT_RT=y kernels and simplify. ] Tested-by: Borislav Petkov <bp@alien8.de>
102 lines
2.8 KiB
C
102 lines
2.8 KiB
C
/* SPDX-License-Identifier: GPL-2.0+ */
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/*
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* Read-Copy Update mechanism for mutual exclusion, the Bloatwatch edition.
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*
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* Copyright IBM Corporation, 2008
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*
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* Author: Paul E. McKenney <paulmck@linux.ibm.com>
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*
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* For detailed explanation of Read-Copy Update mechanism see -
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* Documentation/RCU
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*/
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#ifndef __LINUX_TINY_H
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#define __LINUX_TINY_H
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#include <asm/param.h> /* for HZ */
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/* Never flag non-existent other CPUs! */
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static inline bool rcu_eqs_special_set(int cpu) { return false; }
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static inline unsigned long get_state_synchronize_rcu(void)
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{
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return 0;
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}
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static inline void cond_synchronize_rcu(unsigned long oldstate)
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{
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might_sleep();
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}
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extern void rcu_barrier(void);
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static inline void synchronize_rcu_expedited(void)
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{
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synchronize_rcu();
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}
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static inline void kfree_call_rcu(struct rcu_head *head, rcu_callback_t func)
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{
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call_rcu(head, func);
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}
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void rcu_qs(void);
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static inline void rcu_softirq_qs(void)
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{
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rcu_qs();
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}
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#define rcu_note_context_switch(preempt) \
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do { \
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rcu_qs(); \
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rcu_tasks_qs(current); \
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} while (0)
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static inline int rcu_needs_cpu(u64 basemono, u64 *nextevt)
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{
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*nextevt = KTIME_MAX;
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return 0;
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}
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/*
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* Take advantage of the fact that there is only one CPU, which
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* allows us to ignore virtualization-based context switches.
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*/
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static inline void rcu_virt_note_context_switch(int cpu) { }
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static inline void rcu_cpu_stall_reset(void) { }
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static inline int rcu_jiffies_till_stall_check(void) { return 21 * HZ; }
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static inline void rcu_idle_enter(void) { }
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static inline void rcu_idle_exit(void) { }
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static inline void rcu_irq_enter(void) { }
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static inline void rcu_irq_exit_irqson(void) { }
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static inline void rcu_irq_enter_irqson(void) { }
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static inline void rcu_irq_exit(void) { }
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static inline void exit_rcu(void) { }
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static inline bool rcu_preempt_need_deferred_qs(struct task_struct *t)
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{
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return false;
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}
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static inline void rcu_preempt_deferred_qs(struct task_struct *t) { }
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#ifdef CONFIG_SRCU
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void rcu_scheduler_starting(void);
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#else /* #ifndef CONFIG_SRCU */
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static inline void rcu_scheduler_starting(void) { }
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#endif /* #else #ifndef CONFIG_SRCU */
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static inline void rcu_end_inkernel_boot(void) { }
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static inline bool rcu_inkernel_boot_has_ended(void) { return true; }
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static inline bool rcu_is_watching(void) { return true; }
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static inline void rcu_momentary_dyntick_idle(void) { }
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static inline void kfree_rcu_scheduler_running(void) { }
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/* Avoid RCU read-side critical sections leaking across. */
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static inline void rcu_all_qs(void) { barrier(); }
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/* RCUtree hotplug events */
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#define rcutree_prepare_cpu NULL
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#define rcutree_online_cpu NULL
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#define rcutree_offline_cpu NULL
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#define rcutree_dead_cpu NULL
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#define rcutree_dying_cpu NULL
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static inline void rcu_cpu_starting(unsigned int cpu) { }
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#endif /* __LINUX_RCUTINY_H */
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