1 files changed, 49 insertions, 33 deletions

diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index d2a0046f63b2..4a525a30e08e 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -90,12 +90,12 @@ struct rcu_dynticks {
  * Definition for node within the RCU grace-period-detection hierarchy.
  */
 struct rcu_node {
-        spinlock_t lock;        /* Root rcu_node's lock protects some */
+        raw_spinlock_t lock;    /* Root rcu_node's lock protects some */
                                 /*  rcu_state fields as well as following. */
-        long    gpnum;          /* Current grace period for this node. */
+        unsigned long gpnum;    /* Current grace period for this node. */
                                 /*  This will either be equal to or one */
                                 /*  behind the root rcu_node's gpnum. */
-        long    completed;      /* Last grace period completed for this node. */
+        unsigned long completed; /* Last GP completed for this node. */
                                 /*  This will either be equal to or one */
                                 /*  behind the root rcu_node's gpnum. */
         unsigned long qsmask;   /* CPUs or groups that need to switch in */
@@ -161,11 +161,11 @@ struct rcu_node {
 /* Per-CPU data for read-copy update. */
 struct rcu_data {
         /* 1) quiescent-state and grace-period handling : */
-        long            completed;      /* Track rsp->completed gp number */
+        unsigned long   completed;      /* Track rsp->completed gp number */
                                         /*  in order to detect GP end. */
-        long            gpnum;          /* Highest gp number that this CPU */
+        unsigned long   gpnum;          /* Highest gp number that this CPU */
                                         /*  is aware of having started. */
-        long            passed_quiesc_completed;
+        unsigned long   passed_quiesc_completed;
                                         /* Value of completed at time of qs. */
         bool            passed_quiesc;  /* User-mode/idle loop etc. */
         bool            qs_pending;     /* Core waits for quiesc state. */
@@ -221,14 +221,14 @@ struct rcu_data {
         unsigned long resched_ipi;      /* Sent a resched IPI. */
 
         /* 5) __rcu_pending() statistics. */
-        long n_rcu_pending;             /* rcu_pending() calls since boot. */
-        long n_rp_qs_pending;
-        long n_rp_cb_ready;
-        long n_rp_cpu_needs_gp;
-        long n_rp_gp_completed;
-        long n_rp_gp_started;
-        long n_rp_need_fqs;
-        long n_rp_need_nothing;
+        unsigned long n_rcu_pending;    /* rcu_pending() calls since boot. */
+        unsigned long n_rp_qs_pending;
+        unsigned long n_rp_cb_ready;
+        unsigned long n_rp_cpu_needs_gp;
+        unsigned long n_rp_gp_completed;
+        unsigned long n_rp_gp_started;
+        unsigned long n_rp_need_fqs;
+        unsigned long n_rp_need_nothing;
 
         int cpu;
 };
@@ -237,25 +237,36 @@ struct rcu_data {
 #define RCU_GP_IDLE             0       /* No grace period in progress. */
 #define RCU_GP_INIT             1       /* Grace period being initialized. */
 #define RCU_SAVE_DYNTICK        2       /* Need to scan dyntick state. */
-#define RCU_SAVE_COMPLETED      3       /* Need to save rsp->completed. */
-#define RCU_FORCE_QS            4       /* Need to force quiescent state. */
+#define RCU_FORCE_QS            3       /* Need to force quiescent state. */
 #ifdef CONFIG_NO_HZ
 #define RCU_SIGNAL_INIT         RCU_SAVE_DYNTICK
 #else /* #ifdef CONFIG_NO_HZ */
-#define RCU_SIGNAL_INIT         RCU_SAVE_COMPLETED
+#define RCU_SIGNAL_INIT         RCU_FORCE_QS
 #endif /* #else #ifdef CONFIG_NO_HZ */
 
 #define RCU_JIFFIES_TILL_FORCE_QS        3      /* for rsp->jiffies_force_qs */
 #ifdef CONFIG_RCU_CPU_STALL_DETECTOR
-#define RCU_SECONDS_TILL_STALL_CHECK   (10 * HZ)  /* for rsp->jiffies_stall */
-#define RCU_SECONDS_TILL_STALL_RECHECK (30 * HZ)  /* for rsp->jiffies_stall */
-#define RCU_STALL_RAT_DELAY             2         /* Allow other CPUs time */
-                                                  /*  to take at least one */
-                                                  /*  scheduling clock irq */
-                                                  /*  before ratting on them. */
+
+#ifdef CONFIG_PROVE_RCU
+#define RCU_STALL_DELAY_DELTA          (5 * HZ)
+#else
+#define RCU_STALL_DELAY_DELTA          0
+#endif
+
+#define RCU_SECONDS_TILL_STALL_CHECK   (10 * HZ + RCU_STALL_DELAY_DELTA)
+                                                /* for rsp->jiffies_stall */
+#define RCU_SECONDS_TILL_STALL_RECHECK (30 * HZ + RCU_STALL_DELAY_DELTA)
+                                                /* for rsp->jiffies_stall */
+#define RCU_STALL_RAT_DELAY             2       /* Allow other CPUs time */
+                                                /*  to take at least one */
+                                                /*  scheduling clock irq */
+                                                /*  before ratting on them. */
 
 #endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
 
+#define ULONG_CMP_GE(a, b)      (ULONG_MAX / 2 >= (a) - (b))
+#define ULONG_CMP_LT(a, b)      (ULONG_MAX / 2 < (a) - (b))
+
 /*
  * RCU global state, including node hierarchy.  This hierarchy is
  * represented in "heap" form in a dense array.  The root (first level)
@@ -277,12 +288,19 @@ struct rcu_state {
 
         u8      signaled ____cacheline_internodealigned_in_smp;
                                                 /* Force QS state. */
-        long    gpnum;                          /* Current gp number. */
-        long    completed;                      /* # of last completed gp. */
+        u8      fqs_active;                     /* force_quiescent_state() */
+                                                /*  is running. */
+        u8      fqs_need_gp;                    /* A CPU was prevented from */
+                                                /*  starting a new grace */
+                                                /*  period because */
+                                                /*  force_quiescent_state() */
+                                                /*  was running. */
+        unsigned long gpnum;                    /* Current gp number. */
+        unsigned long completed;                /* # of last completed gp. */
 
         /* End of fields guarded by root rcu_node's lock. */
 
-        spinlock_t onofflock;                   /* exclude on/offline and */
+        raw_spinlock_t onofflock;               /* exclude on/offline and */
                                                 /*  starting new GP.  Also */
                                                 /*  protects the following */
                                                 /*  orphan_cbs fields. */
@@ -292,10 +310,8 @@ struct rcu_state {
                                                 /*  going offline. */
         struct rcu_head **orphan_cbs_tail;      /* And tail pointer. */
         long orphan_qlen;                       /* Number of orphaned cbs. */
-        spinlock_t fqslock;                     /* Only one task forcing */
+        raw_spinlock_t fqslock;                 /* Only one task forcing */
                                                 /*  quiescent states. */
-        long    completed_fqs;                  /* Value of completed @ snap. */
-                                                /*  Protected by fqslock. */
         unsigned long jiffies_force_qs;         /* Time at which to invoke */
                                                 /*  force_quiescent_state(). */
         unsigned long n_force_qs;               /* Number of calls to */
@@ -319,8 +335,6 @@ struct rcu_state {
 #define RCU_OFL_TASKS_EXP_GP    0x2             /* Tasks blocking expedited */
                                                 /*  GP were moved to root. */
 
-#ifdef RCU_TREE_NONCORE
-
 /*
  * RCU implementation internal declarations:
  */
@@ -335,7 +349,7 @@ extern struct rcu_state rcu_preempt_state;
 DECLARE_PER_CPU(struct rcu_data, rcu_preempt_data);
 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
 
-#else /* #ifdef RCU_TREE_NONCORE */
+#ifndef RCU_TREE_NONCORE
 
 /* Forward declarations for rcutree_plugin.h */
 static void rcu_bootup_announce(void);
@@ -347,6 +361,7 @@ static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp,
                                       unsigned long flags);
 #endif /* #ifdef CONFIG_HOTPLUG_CPU */
 #ifdef CONFIG_RCU_CPU_STALL_DETECTOR
+static void rcu_print_detail_task_stall(struct rcu_state *rsp);
 static void rcu_print_task_stall(struct rcu_node *rnp);
 #endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
 static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp);
@@ -367,5 +382,6 @@ static int rcu_preempt_needs_cpu(int cpu);
 static void __cpuinit rcu_preempt_init_percpu_data(int cpu);
 static void rcu_preempt_send_cbs_to_orphanage(void);
 static void __init __rcu_init_preempt(void);
+static void rcu_needs_cpu_flush(void);
 
-#endif /* #else #ifdef RCU_TREE_NONCORE */
+#endif /* #ifndef RCU_TREE_NONCORE */