summaryrefslogtreecommitdiff
path: root/include/linux/srcu.h
diff options
context:
space:
mode:
authorPaul E. McKenney <paulmck@linux.vnet.ibm.com>2017-03-25 19:59:38 +0300
committerPaul E. McKenney <paulmck@linux.vnet.ibm.com>2017-04-18 21:38:22 +0300
commitd8be81735aa89413b333de488251f0e64e2be591 (patch)
tree3c7743a43efeb407aa51b2a8c699de19a9e90500 /include/linux/srcu.h
parentdde8da6cffe73dab81aca3855e717e40db35178c (diff)
downloadlinux-d8be81735aa89413b333de488251f0e64e2be591.tar.xz
srcu: Create a tiny SRCU
In response to automated complaints about modifications to SRCU increasing its size, this commit creates a tiny SRCU that is used in SMP=n && PREEMPT=n builds. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'include/linux/srcu.h')
-rw-r--r--include/linux/srcu.h69
1 files changed, 8 insertions, 61 deletions
diff --git a/include/linux/srcu.h b/include/linux/srcu.h
index 73a1b6296224..907f09b14eda 100644
--- a/include/linux/srcu.h
+++ b/include/linux/srcu.h
@@ -34,28 +34,7 @@
#include <linux/workqueue.h>
#include <linux/rcu_segcblist.h>
-struct srcu_array {
- unsigned long lock_count[2];
- unsigned long unlock_count[2];
-};
-
-struct srcu_struct {
- unsigned long completed;
- unsigned long srcu_gp_seq;
- atomic_t srcu_exp_cnt;
- struct srcu_array __percpu *per_cpu_ref;
- spinlock_t queue_lock; /* protect ->srcu_cblist */
- struct rcu_segcblist srcu_cblist;
- struct delayed_work work;
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
- struct lockdep_map dep_map;
-#endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
-};
-
-/* Values for -> state variable. */
-#define SRCU_STATE_IDLE 0
-#define SRCU_STATE_SCAN1 1
-#define SRCU_STATE_SCAN2 2
+struct srcu_struct;
#ifdef CONFIG_DEBUG_LOCK_ALLOC
@@ -77,42 +56,13 @@ int init_srcu_struct(struct srcu_struct *sp);
#define __SRCU_DEP_MAP_INIT(srcu_name)
#endif /* #else #ifdef CONFIG_DEBUG_LOCK_ALLOC */
-void process_srcu(struct work_struct *work);
-
-#define __SRCU_STRUCT_INIT(name) \
- { \
- .completed = -300, \
- .per_cpu_ref = &name##_srcu_array, \
- .queue_lock = __SPIN_LOCK_UNLOCKED(name.queue_lock), \
- .srcu_cblist = RCU_SEGCBLIST_INITIALIZER(name.srcu_cblist),\
- .work = __DELAYED_WORK_INITIALIZER(name.work, process_srcu, 0),\
- __SRCU_DEP_MAP_INIT(name) \
- }
-
-/*
- * Define and initialize a srcu struct at build time.
- * Do -not- call init_srcu_struct() nor cleanup_srcu_struct() on it.
- *
- * Note that although DEFINE_STATIC_SRCU() hides the name from other
- * files, the per-CPU variable rules nevertheless require that the
- * chosen name be globally unique. These rules also prohibit use of
- * DEFINE_STATIC_SRCU() within a function. If these rules are too
- * restrictive, declare the srcu_struct manually. For example, in
- * each file:
- *
- * static struct srcu_struct my_srcu;
- *
- * Then, before the first use of each my_srcu, manually initialize it:
- *
- * init_srcu_struct(&my_srcu);
- *
- * See include/linux/percpu-defs.h for the rules on per-CPU variables.
- */
-#define __DEFINE_SRCU(name, is_static) \
- static DEFINE_PER_CPU(struct srcu_array, name##_srcu_array);\
- is_static struct srcu_struct name = __SRCU_STRUCT_INIT(name)
-#define DEFINE_SRCU(name) __DEFINE_SRCU(name, /* not static */)
-#define DEFINE_STATIC_SRCU(name) __DEFINE_SRCU(name, static)
+#ifdef CONFIG_TINY_SRCU
+#include <linux/srcutiny.h>
+#elif defined(CONFIG_TREE_SRCU)
+#include <linux/srcutree.h>
+#else
+#error "Unknown SRCU implementation specified to kernel configuration"
+#endif
/**
* call_srcu() - Queue a callback for invocation after an SRCU grace period
@@ -138,9 +88,6 @@ void cleanup_srcu_struct(struct srcu_struct *sp);
int __srcu_read_lock(struct srcu_struct *sp) __acquires(sp);
void __srcu_read_unlock(struct srcu_struct *sp, int idx) __releases(sp);
void synchronize_srcu(struct srcu_struct *sp);
-void synchronize_srcu_expedited(struct srcu_struct *sp);
-unsigned long srcu_batches_completed(struct srcu_struct *sp);
-void srcu_barrier(struct srcu_struct *sp);
#ifdef CONFIG_DEBUG_LOCK_ALLOC