rcu: Stop silencing lockdep false positive for expedited grace periods

[deliverable/linux.git] / kernel / rcu / tree.h

diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
index a57f25ecca58012c986814867308206450f6ae8d..6f3b63b68886b4c56ae7c5edf615ad5440cd49c5 100644 (file)
--- a/kernel/rcu/tree.h
+++ b/kernel/rcu/tree.h
@@ -70,8 +70,6 @@
 #  define RCU_NODE_NAME_INIT  { "rcu_node_0" }
 #  define RCU_FQS_NAME_INIT   { "rcu_node_fqs_0" }
 #  define RCU_EXP_NAME_INIT   { "rcu_node_exp_0" }
-#  define RCU_EXP_SCHED_NAME_INIT \
-                             { "rcu_node_exp_sched_0" }
 #elif NR_CPUS <= RCU_FANOUT_2
 #  define RCU_NUM_LVLS       2
 #  define NUM_RCU_LVL_0              1
@@ -81,8 +79,6 @@
 #  define RCU_NODE_NAME_INIT  { "rcu_node_0", "rcu_node_1" }
 #  define RCU_FQS_NAME_INIT   { "rcu_node_fqs_0", "rcu_node_fqs_1" }
 #  define RCU_EXP_NAME_INIT   { "rcu_node_exp_0", "rcu_node_exp_1" }
-#  define RCU_EXP_SCHED_NAME_INIT \
-                             { "rcu_node_exp_sched_0", "rcu_node_exp_sched_1" }
 #elif NR_CPUS <= RCU_FANOUT_3
 #  define RCU_NUM_LVLS       3
 #  define NUM_RCU_LVL_0              1
@@ -93,8 +89,6 @@
 #  define RCU_NODE_NAME_INIT  { "rcu_node_0", "rcu_node_1", "rcu_node_2" }
 #  define RCU_FQS_NAME_INIT   { "rcu_node_fqs_0", "rcu_node_fqs_1", "rcu_node_fqs_2" }
 #  define RCU_EXP_NAME_INIT   { "rcu_node_exp_0", "rcu_node_exp_1", "rcu_node_exp_2" }
-#  define RCU_EXP_SCHED_NAME_INIT \
-                             { "rcu_node_exp_sched_0", "rcu_node_exp_sched_1", "rcu_node_exp_sched_2" }
 #elif NR_CPUS <= RCU_FANOUT_4
 #  define RCU_NUM_LVLS       4
 #  define NUM_RCU_LVL_0              1
@@ -106,8 +100,6 @@
 #  define RCU_NODE_NAME_INIT  { "rcu_node_0", "rcu_node_1", "rcu_node_2", "rcu_node_3" }
 #  define RCU_FQS_NAME_INIT   { "rcu_node_fqs_0", "rcu_node_fqs_1", "rcu_node_fqs_2", "rcu_node_fqs_3" }
 #  define RCU_EXP_NAME_INIT   { "rcu_node_exp_0", "rcu_node_exp_1", "rcu_node_exp_2", "rcu_node_exp_3" }
-#  define RCU_EXP_SCHED_NAME_INIT \
-                             { "rcu_node_exp_sched_0", "rcu_node_exp_sched_1", "rcu_node_exp_sched_2", "rcu_node_exp_sched_3" }
 #else
 # error "CONFIG_RCU_FANOUT insufficient for NR_CPUS"
 #endif /* #if (NR_CPUS) <= RCU_FANOUT_1 */
@@ -286,6 +278,18 @@ struct rcu_node {
        for ((rnp) = (rsp)->level[rcu_num_lvls - 1]; \
             (rnp) < &(rsp)->node[rcu_num_nodes]; (rnp)++)
 
+/*
+ * Union to allow "aggregate OR" operation on the need for a quiescent
+ * state by the normal and expedited grace periods.
+ */
+union rcu_noqs {
+       struct {
+               u8 norm;
+               u8 exp;
+       } b; /* Bits. */
+       u16 s; /* Set of bits, aggregate OR here. */
+};
+
 /* Index values for nxttail array in struct rcu_data. */
 #define RCU_DONE_TAIL          0       /* Also RCU_WAIT head. */
 #define RCU_WAIT_TAIL          1       /* Also RCU_NEXT_READY head. */
@@ -302,8 +306,8 @@ struct rcu_data {
                                        /*  is aware of having started. */
        unsigned long   rcu_qs_ctr_snap;/* Snapshot of rcu_qs_ctr to check */
                                        /*  for rcu_all_qs() invocations. */
-       bool            passed_quiesce; /* User-mode/idle loop etc. */
-       bool            qs_pending;     /* Core waits for quiesc state. */
+       union rcu_noqs  cpu_no_qs;      /* No QSes yet for this CPU. */
+       bool            core_needs_qs;  /* Core waits for quiesc state. */
        bool            beenonline;     /* CPU online at least once. */
        bool            gpwrap;         /* Possible gpnum/completed wrap. */
        struct rcu_node *mynode;        /* This CPU's leaf of hierarchy */
@@ -312,9 +316,6 @@ struct rcu_data {
                                        /*  ticks this CPU has handled */
                                        /*  during and after the last grace */
                                        /* period it is aware of. */
-       struct cpu_stop_work exp_stop_work;
-                                       /* Expedited grace-period control */
-                                       /*  for CPU stopping. */
 
        /* 2) batch handling */
        /*
@@ -368,7 +369,7 @@ struct rcu_data {
 
        /* 5) __rcu_pending() statistics. */
        unsigned long n_rcu_pending;    /* rcu_pending() calls since boot. */
-       unsigned long n_rp_qs_pending;
+       unsigned long n_rp_core_needs_qs;
        unsigned long n_rp_report_qs;
        unsigned long n_rp_cb_ready;
        unsigned long n_rp_cpu_needs_gp;
@@ -383,7 +384,6 @@ struct rcu_data {
        struct rcu_head oom_head;
 #endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */
        struct mutex exp_funnel_mutex;
-       bool exp_done;                  /* Expedited QS for this CPU? */
 
        /* 7) Callback offloading. */
 #ifdef CONFIG_RCU_NOCB_CPU