Commit d1ec4c34 authored by Paul E. McKenney's avatar Paul E. McKenney
Browse files

rcu: Drop RCU_USER_QS in favor of NO_HZ_FULL 



The RCU_USER_QS Kconfig parameter is now just a synonym for NO_HZ_FULL,
so this commit eliminates RCU_USER_QS, replacing all uses with NO_HZ_FULL.

Reported-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
parent d770e558

include/linux/rcupdate.h

+2 −2
Original line number Diff line number Diff line
@@ -309,7 +309,7 @@ static inline void rcu_sysrq_end(void) 
}

#endif /* #else #ifdef CONFIG_RCU_STALL_COMMON */



#ifdef CONFIG_RCU_USER_QS

#ifdef CONFIG_NO_HZ_FULL

void rcu_user_enter(void);

void rcu_user_exit(void);

#else
@@ -317,7 +317,7 @@ static inline void rcu_user_enter(void) { } 
static inline void rcu_user_exit(void) { }

static inline void rcu_user_hooks_switch(struct task_struct *prev,

					 struct task_struct *next) { }

#endif /* CONFIG_RCU_USER_QS */

#endif /* CONFIG_NO_HZ_FULL */



#ifdef CONFIG_RCU_NOCB_CPU

void rcu_init_nohz(void);

init/Kconfig

+0 −9
Original line number Diff line number Diff line
@@ -538,15 +538,6 @@ config RCU_STALL_COMMON 
config CONTEXT_TRACKING

       bool



config RCU_USER_QS

	bool

	help

	  This option sets hooks on kernel / userspace boundaries and

	  puts RCU in extended quiescent state when the CPU runs in

	  userspace. It means that when a CPU runs in userspace, it is

	  excluded from the global RCU state machine and thus doesn't

	  try to keep the timer tick on for RCU.



config CONTEXT_TRACKING_FORCE

	bool "Force context tracking"

	depends on CONTEXT_TRACKING

kernel/rcu/tree.c

+4 −4
Original line number Diff line number Diff line
@@ -701,7 +701,7 @@ void rcu_idle_enter(void) 
}

EXPORT_SYMBOL_GPL(rcu_idle_enter);



#ifdef CONFIG_RCU_USER_QS

#ifdef CONFIG_NO_HZ_FULL

/**

 * rcu_user_enter - inform RCU that we are resuming userspace.

 *
@@ -714,7 +714,7 @@ void rcu_user_enter(void) 
{

	rcu_eqs_enter(1);

}

#endif /* CONFIG_RCU_USER_QS */

#endif /* CONFIG_NO_HZ_FULL */



/**

 * rcu_irq_exit - inform RCU that current CPU is exiting irq towards idle
@@ -828,7 +828,7 @@ void rcu_idle_exit(void) 
}

EXPORT_SYMBOL_GPL(rcu_idle_exit);



#ifdef CONFIG_RCU_USER_QS

#ifdef CONFIG_NO_HZ_FULL

/**

 * rcu_user_exit - inform RCU that we are exiting userspace.

 *
@@ -839,7 +839,7 @@ void rcu_user_exit(void) 
{

	rcu_eqs_exit(1);

}

#endif /* CONFIG_RCU_USER_QS */

#endif /* CONFIG_NO_HZ_FULL */



/**

 * rcu_irq_enter - inform RCU that current CPU is entering irq away from idle

kernel/time/Kconfig

+0 −2
Original line number Diff line number Diff line
@@ -92,12 +92,10 @@ config NO_HZ_FULL 
	depends on !ARCH_USES_GETTIMEOFFSET && GENERIC_CLOCKEVENTS

	# We need at least one periodic CPU for timekeeping

	depends on SMP

	# RCU_USER_QS dependency

	depends on HAVE_CONTEXT_TRACKING

	# VIRT_CPU_ACCOUNTING_GEN dependency

	depends on HAVE_VIRT_CPU_ACCOUNTING_GEN

	select NO_HZ_COMMON

	select RCU_USER_QS

	select RCU_NOCB_CPU

	select VIRT_CPU_ACCOUNTING_GEN

	select IRQ_WORK

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