diff options
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/rcutree.c | 27 | ||||
-rw-r--r-- | kernel/rcutree_plugin.h | 10 |
2 files changed, 11 insertions, 26 deletions
diff --git a/kernel/rcutree.c b/kernel/rcutree.c index e8624ebf2320..ae4a553e37ce 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c | |||
@@ -767,10 +767,10 @@ cpu_quiet_msk(unsigned long mask, struct rcu_state *rsp, struct rcu_node *rnp, | |||
767 | 767 | ||
768 | /* | 768 | /* |
769 | * Record a quiescent state for the specified CPU, which must either be | 769 | * Record a quiescent state for the specified CPU, which must either be |
770 | * the current CPU or an offline CPU. The lastcomp argument is used to | 770 | * the current CPU. The lastcomp argument is used to make sure we are |
771 | * make sure we are still in the grace period of interest. We don't want | 771 | * still in the grace period of interest. We don't want to end the current |
772 | * to end the current grace period based on quiescent states detected in | 772 | * grace period based on quiescent states detected in an earlier grace |
773 | * an earlier grace period! | 773 | * period! |
774 | */ | 774 | */ |
775 | static void | 775 | static void |
776 | cpu_quiet(int cpu, struct rcu_state *rsp, struct rcu_data *rdp, long lastcomp) | 776 | cpu_quiet(int cpu, struct rcu_state *rsp, struct rcu_data *rdp, long lastcomp) |
@@ -805,7 +805,6 @@ cpu_quiet(int cpu, struct rcu_state *rsp, struct rcu_data *rdp, long lastcomp) | |||
805 | * This GP can't end until cpu checks in, so all of our | 805 | * This GP can't end until cpu checks in, so all of our |
806 | * callbacks can be processed during the next GP. | 806 | * callbacks can be processed during the next GP. |
807 | */ | 807 | */ |
808 | rdp = rsp->rda[smp_processor_id()]; | ||
809 | rdp->nxttail[RCU_NEXT_READY_TAIL] = rdp->nxttail[RCU_NEXT_TAIL]; | 808 | rdp->nxttail[RCU_NEXT_READY_TAIL] = rdp->nxttail[RCU_NEXT_TAIL]; |
810 | 809 | ||
811 | cpu_quiet_msk(mask, rsp, rnp, flags); /* releases rnp->lock */ | 810 | cpu_quiet_msk(mask, rsp, rnp, flags); /* releases rnp->lock */ |
@@ -881,9 +880,6 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp) | |||
881 | 880 | ||
882 | spin_unlock(&rsp->onofflock); /* irqs remain disabled. */ | 881 | spin_unlock(&rsp->onofflock); /* irqs remain disabled. */ |
883 | 882 | ||
884 | /* Being offline is a quiescent state, so go record it. */ | ||
885 | cpu_quiet(cpu, rsp, rdp, lastcomp); | ||
886 | |||
887 | /* | 883 | /* |
888 | * Move callbacks from the outgoing CPU to the running CPU. | 884 | * Move callbacks from the outgoing CPU to the running CPU. |
889 | * Note that the outgoing CPU is now quiscent, so it is now | 885 | * Note that the outgoing CPU is now quiscent, so it is now |
@@ -1448,20 +1444,7 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp, int preemptable) | |||
1448 | rnp = rnp->parent; | 1444 | rnp = rnp->parent; |
1449 | } while (rnp != NULL && !(rnp->qsmaskinit & mask)); | 1445 | } while (rnp != NULL && !(rnp->qsmaskinit & mask)); |
1450 | 1446 | ||
1451 | spin_unlock(&rsp->onofflock); /* irqs remain disabled. */ | 1447 | spin_unlock_irqrestore(&rsp->onofflock, flags); |
1452 | |||
1453 | /* | ||
1454 | * A new grace period might start here. If so, we will be part of | ||
1455 | * it, and its gpnum will be greater than ours, so we will | ||
1456 | * participate. It is also possible for the gpnum to have been | ||
1457 | * incremented before this function was called, and the bitmasks | ||
1458 | * to not be filled out until now, in which case we will also | ||
1459 | * participate due to our gpnum being behind. | ||
1460 | */ | ||
1461 | |||
1462 | /* Since it is coming online, the CPU is in a quiescent state. */ | ||
1463 | cpu_quiet(cpu, rsp, rdp, lastcomp); | ||
1464 | local_irq_restore(flags); | ||
1465 | } | 1448 | } |
1466 | 1449 | ||
1467 | static void __cpuinit rcu_online_cpu(int cpu) | 1450 | static void __cpuinit rcu_online_cpu(int cpu) |
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index 5f94619450af..cd6047cc7fc2 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h | |||
@@ -117,9 +117,9 @@ static void rcu_preempt_note_context_switch(int cpu) | |||
117 | * on line! | 117 | * on line! |
118 | */ | 118 | */ |
119 | WARN_ON_ONCE((rdp->grpmask & rnp->qsmaskinit) == 0); | 119 | WARN_ON_ONCE((rdp->grpmask & rnp->qsmaskinit) == 0); |
120 | phase = !(rnp->qsmask & rdp->grpmask) ^ (rnp->gpnum & 0x1); | 120 | WARN_ON_ONCE(!list_empty(&t->rcu_node_entry)); |
121 | phase = (rnp->gpnum + !(rnp->qsmask & rdp->grpmask)) & 0x1; | ||
121 | list_add(&t->rcu_node_entry, &rnp->blocked_tasks[phase]); | 122 | list_add(&t->rcu_node_entry, &rnp->blocked_tasks[phase]); |
122 | smp_mb(); /* Ensure later ctxt swtch seen after above. */ | ||
123 | spin_unlock_irqrestore(&rnp->lock, flags); | 123 | spin_unlock_irqrestore(&rnp->lock, flags); |
124 | } | 124 | } |
125 | 125 | ||
@@ -133,7 +133,9 @@ static void rcu_preempt_note_context_switch(int cpu) | |||
133 | * means that we continue to block the current grace period. | 133 | * means that we continue to block the current grace period. |
134 | */ | 134 | */ |
135 | rcu_preempt_qs(cpu); | 135 | rcu_preempt_qs(cpu); |
136 | local_irq_save(flags); | ||
136 | t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS; | 137 | t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS; |
138 | local_irq_restore(flags); | ||
137 | } | 139 | } |
138 | 140 | ||
139 | /* | 141 | /* |
@@ -189,10 +191,10 @@ static void rcu_read_unlock_special(struct task_struct *t) | |||
189 | */ | 191 | */ |
190 | for (;;) { | 192 | for (;;) { |
191 | rnp = t->rcu_blocked_node; | 193 | rnp = t->rcu_blocked_node; |
192 | spin_lock(&rnp->lock); | 194 | spin_lock(&rnp->lock); /* irqs already disabled. */ |
193 | if (rnp == t->rcu_blocked_node) | 195 | if (rnp == t->rcu_blocked_node) |
194 | break; | 196 | break; |
195 | spin_unlock(&rnp->lock); | 197 | spin_unlock(&rnp->lock); /* irqs remain disabled. */ |
196 | } | 198 | } |
197 | empty = list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1]); | 199 | empty = list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1]); |
198 | list_del_init(&t->rcu_node_entry); | 200 | list_del_init(&t->rcu_node_entry); |