irqdomain: Remove powerpc dependency from debugfs file

[linux-flexiantxendom0-3.2.10.git] / kernel / rcu.h

diff --git a/kernel/rcu.h b/kernel/rcu.h
index 7bc1643..8ba99cd 100644 (file)
--- a/kernel/rcu.h
+++ b/kernel/rcu.h
@@ -23,6 +23,38 @@
 #ifndef __LINUX_RCU_H
 #define __LINUX_RCU_H
 
+#ifdef CONFIG_RCU_TRACE
+#define RCU_TRACE(stmt) stmt
+#else /* #ifdef CONFIG_RCU_TRACE */
+#define RCU_TRACE(stmt)
+#endif /* #else #ifdef CONFIG_RCU_TRACE */
+
+/*
+ * Process-level increment to ->dynticks_nesting field.  This allows for
+ * architectures that use half-interrupts and half-exceptions from
+ * process context.
+ *
+ * DYNTICK_TASK_NEST_MASK defines a field of width DYNTICK_TASK_NEST_WIDTH
+ * that counts the number of process-based reasons why RCU cannot
+ * consider the corresponding CPU to be idle, and DYNTICK_TASK_NEST_VALUE
+ * is the value used to increment or decrement this field.
+ *
+ * The rest of the bits could in principle be used to count interrupts,
+ * but this would mean that a negative-one value in the interrupt
+ * field could incorrectly zero out the DYNTICK_TASK_NEST_MASK field.
+ * We therefore provide a two-bit guard field defined by DYNTICK_TASK_MASK
+ * that is set to DYNTICK_TASK_FLAG upon initial exit from idle.
+ * The DYNTICK_TASK_EXIT_IDLE value is thus the combined value used upon
+ * initial exit from idle.
+ */
+#define DYNTICK_TASK_NEST_WIDTH 7
+#define DYNTICK_TASK_NEST_VALUE ((LLONG_MAX >> DYNTICK_TASK_NEST_WIDTH) + 1)
+#define DYNTICK_TASK_NEST_MASK  (LLONG_MAX - DYNTICK_TASK_NEST_VALUE + 1)
+#define DYNTICK_TASK_FLAG         ((DYNTICK_TASK_NEST_VALUE / 8) * 2)
+#define DYNTICK_TASK_MASK         ((DYNTICK_TASK_NEST_VALUE / 8) * 3)
+#define DYNTICK_TASK_EXIT_IDLE    (DYNTICK_TASK_NEST_VALUE + \
+                                   DYNTICK_TASK_FLAG)
+
 /*
  * 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
@@ -37,7 +69,6 @@ extern struct debug_obj_descr rcuhead_debug_descr;
 
 static inline void debug_rcu_head_queue(struct rcu_head *head)
 {
-       WARN_ON_ONCE((unsigned long)head & 0x3);
        debug_object_activate(head, &rcuhead_debug_descr);
        debug_object_active_state(head, &rcuhead_debug_descr,
                                  STATE_RCU_HEAD_READY,
@@ -63,16 +94,18 @@ static inline void debug_rcu_head_unqueue(struct rcu_head *head)
 
 extern void kfree(const void *);
 
-static inline void __rcu_reclaim(struct rcu_head *head)
+static inline bool __rcu_reclaim(char *rn, struct rcu_head *head)
 {
        unsigned long offset = (unsigned long)head->func;
 
        if (__is_kfree_rcu_offset(offset)) {
-               trace_rcu_invoke_kfree_callback(head, offset);
+               RCU_TRACE(trace_rcu_invoke_kfree_callback(rn, head, offset));
                kfree((void *)head - offset);
+               return 1;
        } else {
-               trace_rcu_invoke_callback(head);
+               RCU_TRACE(trace_rcu_invoke_callback(rn, head));
                head->func(head);
+               return 0;
        }
 }