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author | Linus Torvalds | 2010-08-06 18:23:07 +0200 |
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committer | Linus Torvalds | 2010-08-06 18:23:07 +0200 |
commit | 3a3527b6461b1298cc53ce72f336346739297ac8 (patch) | |
tree | 30bea5dd7163f13d6c962888feaf53f50ead4cce /include | |
parent | Merge branch 'core-iommu-for-linus' of git://git.kernel.org/pub/scm/linux/ker... (diff) | |
parent | Revert "net: Make accesses to ->br_port safe for sparse RCU" (diff) | |
download | kernel-qcow2-linux-3a3527b6461b1298cc53ce72f336346739297ac8.tar.gz kernel-qcow2-linux-3a3527b6461b1298cc53ce72f336346739297ac8.tar.xz kernel-qcow2-linux-3a3527b6461b1298cc53ce72f336346739297ac8.zip |
Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
Revert "net: Make accesses to ->br_port safe for sparse RCU"
mce: convert to rcu_dereference_index_check()
net: Make accesses to ->br_port safe for sparse RCU
vfs: add fs.h to define struct file
lockdep: Add an in_workqueue_context() lockdep-based test function
rcu: add __rcu API for later sparse checking
rcu: add an rcu_dereference_index_check()
tree/tiny rcu: Add debug RCU head objects
mm: remove all rcu head initializations
fs: remove all rcu head initializations, except on_stack initializations
powerpc: remove all rcu head initializations
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/compiler.h | 2 | ||||
-rw-r--r-- | include/linux/fdtable.h | 1 | ||||
-rw-r--r-- | include/linux/rcupdate.h | 82 | ||||
-rw-r--r-- | include/linux/workqueue.h | 4 |
4 files changed, 89 insertions, 0 deletions
diff --git a/include/linux/compiler.h b/include/linux/compiler.h index a5a472b10746..c1a62c56a660 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -16,6 +16,7 @@ # define __release(x) __context__(x,-1) # define __cond_lock(x,c) ((c) ? ({ __acquire(x); 1; }) : 0) # define __percpu __attribute__((noderef, address_space(3))) +# define __rcu extern void __chk_user_ptr(const volatile void __user *); extern void __chk_io_ptr(const volatile void __iomem *); #else @@ -34,6 +35,7 @@ extern void __chk_io_ptr(const volatile void __iomem *); # define __release(x) (void)0 # define __cond_lock(x,c) (c) # define __percpu +# define __rcu #endif #ifdef __KERNEL__ diff --git a/include/linux/fdtable.h b/include/linux/fdtable.h index d147461bc271..f59ed297b661 100644 --- a/include/linux/fdtable.h +++ b/include/linux/fdtable.h @@ -11,6 +11,7 @@ #include <linux/rcupdate.h> #include <linux/types.h> #include <linux/init.h> +#include <linux/fs.h> #include <asm/atomic.h> diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index b653b4aaa8a6..9fbc54a2585d 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -40,6 +40,7 @@ #include <linux/seqlock.h> #include <linux/lockdep.h> #include <linux/completion.h> +#include <linux/debugobjects.h> #ifdef CONFIG_RCU_TORTURE_TEST extern int rcutorture_runnable; /* for sysctl */ @@ -79,6 +80,16 @@ extern void rcu_init(void); (ptr)->next = NULL; (ptr)->func = NULL; \ } while (0) +/* + * init_rcu_head_on_stack()/destroy_rcu_head_on_stack() are needed for dynamic + * initialization and destruction of rcu_head on the stack. rcu_head structures + * allocated dynamically in the heap or defined statically don't need any + * initialization. + */ +#ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD +extern void init_rcu_head_on_stack(struct rcu_head *head); +extern void destroy_rcu_head_on_stack(struct rcu_head *head); +#else /* !CONFIG_DEBUG_OBJECTS_RCU_HEAD */ static inline void init_rcu_head_on_stack(struct rcu_head *head) { } @@ -86,6 +97,7 @@ static inline void init_rcu_head_on_stack(struct rcu_head *head) static inline void destroy_rcu_head_on_stack(struct rcu_head *head) { } +#endif /* #else !CONFIG_DEBUG_OBJECTS_RCU_HEAD */ #ifdef CONFIG_DEBUG_LOCK_ALLOC @@ -517,4 +529,74 @@ extern void call_rcu(struct rcu_head *head, extern void call_rcu_bh(struct rcu_head *head, void (*func)(struct rcu_head *head)); +/* + * debug_rcu_head_queue()/debug_rcu_head_unqueue() are used internally + * by call_rcu() and rcu callback execution, and are therefore not part of the + * RCU API. Leaving in rcupdate.h because they are used by all RCU flavors. + */ + +#ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD +# define STATE_RCU_HEAD_READY 0 +# define STATE_RCU_HEAD_QUEUED 1 + +extern struct debug_obj_descr rcuhead_debug_descr; + +static inline void debug_rcu_head_queue(struct rcu_head *head) +{ + debug_object_activate(head, &rcuhead_debug_descr); + debug_object_active_state(head, &rcuhead_debug_descr, + STATE_RCU_HEAD_READY, + STATE_RCU_HEAD_QUEUED); +} + +static inline void debug_rcu_head_unqueue(struct rcu_head *head) +{ + debug_object_active_state(head, &rcuhead_debug_descr, + STATE_RCU_HEAD_QUEUED, + STATE_RCU_HEAD_READY); + debug_object_deactivate(head, &rcuhead_debug_descr); +} +#else /* !CONFIG_DEBUG_OBJECTS_RCU_HEAD */ +static inline void debug_rcu_head_queue(struct rcu_head *head) +{ +} + +static inline void debug_rcu_head_unqueue(struct rcu_head *head) +{ +} +#endif /* #else !CONFIG_DEBUG_OBJECTS_RCU_HEAD */ + +#ifndef CONFIG_PROVE_RCU +#define __do_rcu_dereference_check(c) do { } while (0) +#endif /* #ifdef CONFIG_PROVE_RCU */ + +#define __rcu_dereference_index_check(p, c) \ + ({ \ + typeof(p) _________p1 = ACCESS_ONCE(p); \ + __do_rcu_dereference_check(c); \ + smp_read_barrier_depends(); \ + (_________p1); \ + }) + +/** + * rcu_dereference_index_check() - rcu_dereference for indices with debug checking + * @p: The pointer to read, prior to dereferencing + * @c: The conditions under which the dereference will take place + * + * Similar to rcu_dereference_check(), but omits the sparse checking. + * This allows rcu_dereference_index_check() to be used on integers, + * which can then be used as array indices. Attempting to use + * rcu_dereference_check() on an integer will give compiler warnings + * because the sparse address-space mechanism relies on dereferencing + * the RCU-protected pointer. Dereferencing integers is not something + * that even gcc will put up with. + * + * Note that this function does not implicitly check for RCU read-side + * critical sections. If this function gains lots of uses, it might + * make sense to provide versions for each flavor of RCU, but it does + * not make sense as of early 2010. + */ +#define rcu_dereference_index_check(p, c) \ + __rcu_dereference_index_check((p), (c)) + #endif /* __LINUX_RCUPDATE_H */ diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h index 9466e860d8c2..d0f7c8178498 100644 --- a/include/linux/workqueue.h +++ b/include/linux/workqueue.h @@ -297,4 +297,8 @@ static inline long work_on_cpu(unsigned int cpu, long (*fn)(void *), void *arg) #else long work_on_cpu(unsigned int cpu, long (*fn)(void *), void *arg); #endif /* CONFIG_SMP */ + +#ifdef CONFIG_LOCKDEP +int in_workqueue_context(struct workqueue_struct *wq); +#endif #endif |