From: Stephen Rothwell <sfr@canb.auug.org.au>
Date: Fri, 24 Aug 2012 04:50:03 +0000 (+1000)
Subject: Merge remote-tracking branch 'rcu/rcu/next'
X-Git-Tag: next-20120824~30
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=9b1eaa53deba3ee4a40df6fc893087dde9f1dc3e;p=karo-tx-linux.git

Merge remote-tracking branch 'rcu/rcu/next'

Conflicts:
	arch/Kconfig
	arch/x86/Kconfig
	include/linux/sched.h
	kernel/rcutree.h
	kernel/rcutree_plugin.h
---

9b1eaa53deba3ee4a40df6fc893087dde9f1dc3e
diff --cc arch/Kconfig
index 07db9299ea86,1c7c9beaa193..d5176b861e32
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@@ -294,26 -274,14 +294,36 @@@ config SECCOMP_FILTE
  
  	  See Documentation/prctl/seccomp_filter.txt for details.
  
 +config HAVE_MOD_ARCH_SPECIFIC
 +	bool
 +	help
 +	  The arch uses struct mod_arch_specific to store data.  Many arches
 +	  just need a simple module loader without arch specific data - those
 +	  should not enable this.
 +
 +config MODULES_USE_ELF_RELA
 +	bool
 +	help
 +	  Modules only use ELF RELA relocations.  Modules with ELF REL
 +	  relocations will give an error.
 +
 +config MODULES_USE_ELF_REL
 +	bool
 +	help
 +	  Modules only use ELF REL relocations.  Modules with ELF RELA
 +	  relocations will give an error.
 +
 +config HAVE_VIRT_CPU_ACCOUNTING
 +	bool
 +
+ config HAVE_RCU_USER_QS
+ 	bool
+ 	help
+ 	  Provide kernel entry/exit hooks necessary for userspace
+ 	  RCU extended quiescent state. Syscalls need to be wrapped inside
+ 	  rcu_user_exit()-rcu_user_enter() through the slow path using
+ 	  TIF_NOHZ flag. Exceptions handlers must be wrapped as well. Irqs
+ 	  are already protected inside rcu_irq_enter/rcu_irq_exit() but
+ 	  preemption or signal handling on irq exit still need to be protected.
+ 
  source "kernel/gcov/Kconfig"
diff --cc arch/x86/Kconfig
index f649a28919df,38dfcc2263cc..1aa157ab13d0
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@@ -99,8 -95,7 +99,9 @@@ config X8
  	select KTIME_SCALAR if X86_32
  	select GENERIC_STRNCPY_FROM_USER
  	select GENERIC_STRNLEN_USER
 +	select MODULES_USE_ELF_REL if X86_32
 +	select MODULES_USE_ELF_RELA if X86_64
+ 	select HAVE_RCU_USER_QS if X86_64
  
  config INSTRUCTION_DECODER
  	def_bool (KPROBES || PERF_EVENTS || UPROBES)
diff --cc include/linux/sched.h
index f3eebc121ebc,a0949597ce97..c44f847657f0
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@@ -1885,13 -1879,14 +1885,21 @@@ static inline void rcu_copy_process(str
  
  #endif
  
 +static inline void tsk_restore_flags(struct task_struct *task,
 +				unsigned long orig_flags, unsigned long flags)
 +{
 +	task->flags &= ~flags;
 +	task->flags |= orig_flags & flags;
 +}
 +
+ static inline void rcu_switch(struct task_struct *prev,
+ 			      struct task_struct *next)
+ {
+ #ifdef CONFIG_RCU_USER_QS
+ 	rcu_user_hooks_switch(prev, next);
+ #endif
+ }
+ 
  #ifdef CONFIG_SMP
  extern void do_set_cpus_allowed(struct task_struct *p,
  			       const struct cpumask *new_mask);
diff --cc kernel/rcutree.h
index 1224d4c05382,c2a3e7d596dc..77340697298f
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@@ -196,6 -200,13 +200,7 @@@ struct rcu_node 
  				/* Refused to boost: not sure why, though. */
  				/*  This can happen due to race conditions. */
  #endif /* #ifdef CONFIG_RCU_BOOST */
 -	struct task_struct *node_kthread_task;
 -				/* kthread that takes care of this rcu_node */
 -				/*  structure, for example, awakening the */
 -				/*  per-CPU kthreads as needed. */
 -	unsigned int node_kthread_status;
 -				/* State of node_kthread_task for tracing. */
+ 	raw_spinlock_t fqslock ____cacheline_internodealigned_in_smp;
  } ____cacheline_internodealigned_in_smp;
  
  /*
diff --cc kernel/rcutree_plugin.h
index c1961aed1213,c3e3fc499788..8432034b2d09
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@@ -25,7 -25,7 +25,8 @@@
   */
  
  #include <linux/delay.h>
 +#include <linux/smpboot.h>
+ #include <linux/oom.h>
  
  #define RCU_KTHREAD_PRIO 1