diff options
| -rw-r--r-- | kernel/rcutree.c | 53 | ||||
| -rw-r--r-- | kernel/rcutree.h | 12 | ||||
| -rw-r--r-- | kernel/rcutree_plugin.h | 4 |
3 files changed, 40 insertions, 29 deletions
diff --git a/kernel/rcutree.c b/kernel/rcutree.c index d5597830faf5..e2e272b5c277 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -462,8 +462,6 @@ static void print_other_cpu_stall(struct rcu_state *rsp) long delta; unsigned long flags; struct rcu_node *rnp = rcu_get_root(rsp); - struct rcu_node *rnp_cur = rsp->level[NUM_RCU_LVLS - 1]; - struct rcu_node *rnp_end = &rsp->node[NUM_RCU_NODES]; /* Only let one CPU complain about others per time interval. */ @@ -474,18 +472,24 @@ static void print_other_cpu_stall(struct rcu_state *rsp) return; } rsp->jiffies_stall = jiffies + RCU_SECONDS_TILL_STALL_RECHECK; + + /* + * Now rat on any tasks that got kicked up to the root rcu_node + * due to CPU offlining. + */ + rcu_print_task_stall(rnp); spin_unlock_irqrestore(&rnp->lock, flags); /* OK, time to rat on our buddy... */ printk(KERN_ERR "INFO: RCU detected CPU stalls:"); - for (; rnp_cur < rnp_end; rnp_cur++) { + rcu_for_each_leaf_node(rsp, rnp) { rcu_print_task_stall(rnp); - if (rnp_cur->qsmask == 0) + if (rnp->qsmask == 0) continue; - for (cpu = 0; cpu <= rnp_cur->grphi - rnp_cur->grplo; cpu++) - if (rnp_cur->qsmask & (1UL << cpu)) - printk(" %d", rnp_cur->grplo + cpu); + for (cpu = 0; cpu <= rnp->grphi - rnp->grplo; cpu++) + if (rnp->qsmask & (1UL << cpu)) + printk(" %d", rnp->grplo + cpu); } printk(" (detected by %d, t=%ld jiffies)\n", smp_processor_id(), (long)(jiffies - rsp->gp_start)); @@ -649,7 +653,7 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags) * one corresponding to this CPU, due to the fact that we have * irqs disabled. */ - for (rnp = &rsp->node[0]; rnp < &rsp->node[NUM_RCU_NODES]; rnp++) { + rcu_for_each_node_breadth_first(rsp, rnp) { spin_lock(&rnp->lock); /* irqs already disabled. */ rcu_preempt_check_blocked_tasks(rnp); rnp->qsmask = rnp->qsmaskinit; @@ -1042,33 +1046,32 @@ static int rcu_process_dyntick(struct rcu_state *rsp, long lastcomp, int cpu; unsigned long flags; unsigned long mask; - struct rcu_node *rnp_cur = rsp->level[NUM_RCU_LVLS - 1]; - struct rcu_node *rnp_end = &rsp->node[NUM_RCU_NODES]; + struct rcu_node *rnp; - for (; rnp_cur < rnp_end; rnp_cur++) { + rcu_for_each_leaf_node(rsp, rnp) { mask = 0; - spin_lock_irqsave(&rnp_cur->lock, flags); + spin_lock_irqsave(&rnp->lock, flags); if (rsp->completed != lastcomp) { - spin_unlock_irqrestore(&rnp_cur->lock, flags); + spin_unlock_irqrestore(&rnp->lock, flags); return 1; } - if (rnp_cur->qsmask == 0) { - spin_unlock_irqrestore(&rnp_cur->lock, flags); + if (rnp->qsmask == 0) { + spin_unlock_irqrestore(&rnp->lock, flags); continue; } - cpu = rnp_cur->grplo; + cpu = rnp->grplo; bit = 1; - for (; cpu <= rnp_cur->grphi; cpu++, bit <<= 1) { - if ((rnp_cur->qsmask & bit) != 0 && f(rsp->rda[cpu])) + for (; cpu <= rnp->grphi; cpu++, bit <<= 1) { + if ((rnp->qsmask & bit) != 0 && f(rsp->rda[cpu])) mask |= bit; } if (mask != 0 && rsp->completed == lastcomp) { - /* cpu_quiet_msk() releases rnp_cur->lock. */ - cpu_quiet_msk(mask, rsp, rnp_cur, flags); + /* cpu_quiet_msk() releases rnp->lock. */ + cpu_quiet_msk(mask, rsp, rnp, flags); continue; } - spin_unlock_irqrestore(&rnp_cur->lock, flags); + spin_unlock_irqrestore(&rnp->lock, flags); } return 0; } @@ -1550,6 +1553,10 @@ static void __init rcu_init_one(struct rcu_state *rsp) */ #define RCU_INIT_FLAVOR(rsp, rcu_data) \ do { \ + int i; \ + int j; \ + struct rcu_node *rnp; \ + \ rcu_init_one(rsp); \ rnp = (rsp)->level[NUM_RCU_LVLS - 1]; \ j = 0; \ @@ -1564,10 +1571,6 @@ do { \ void __init __rcu_init(void) { - int i; /* All used by RCU_INIT_FLAVOR(). */ - int j; - struct rcu_node *rnp; - rcu_bootup_announce(); #ifdef CONFIG_RCU_CPU_STALL_DETECTOR printk(KERN_INFO "RCU-based detection of stalled CPUs is enabled.\n"); diff --git a/kernel/rcutree.h b/kernel/rcutree.h index e6ab31cc28ba..676eecd371d9 100644 --- a/kernel/rcutree.h +++ b/kernel/rcutree.h @@ -106,6 +106,18 @@ struct rcu_node { /* blocked_tasks[] array. */ } ____cacheline_internodealigned_in_smp; +/* + * Do a full breadth-first scan of the rcu_node structures for the + * specified rcu_state structure. + */ +#define rcu_for_each_node_breadth_first(rsp, rnp) \ + for ((rnp) = &(rsp)->node[0]; \ + (rnp) < &(rsp)->node[NUM_RCU_NODES]; (rnp)++) + +#define rcu_for_each_leaf_node(rsp, rnp) \ + for ((rnp) = (rsp)->level[NUM_RCU_LVLS - 1]; \ + (rnp) < &(rsp)->node[NUM_RCU_NODES]; (rnp)++) + /* 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. */ diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index 65250219ab6d..57200fe96d0a 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -423,10 +423,6 @@ static void __cpuinit rcu_preempt_init_percpu_data(int cpu) */ static void __init __rcu_init_preempt(void) { - int i; /* All used by RCU_INIT_FLAVOR(). */ - int j; - struct rcu_node *rnp; - RCU_INIT_FLAVOR(&rcu_preempt_state, rcu_preempt_data); } |