diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/rcutree.c | 27 | ||||
| -rw-r--r-- | kernel/rcutree.h | 2 | ||||
| -rw-r--r-- | kernel/rcutree_plugin.h | 2 | ||||
| -rw-r--r-- | kernel/rcutree_trace.c | 12 |
4 files changed, 16 insertions, 27 deletions
diff --git a/kernel/rcutree.c b/kernel/rcutree.c index a2eadd04fb29..6194402ec853 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -176,8 +176,6 @@ void rcu_sched_qs(int cpu) { struct rcu_data *rdp = &per_cpu(rcu_sched_data, cpu); - rdp->passed_quiesce_gpnum = rdp->gpnum; - barrier(); if (rdp->passed_quiesce == 0) trace_rcu_grace_period("rcu_sched", rdp->gpnum, "cpuqs"); rdp->passed_quiesce = 1; @@ -187,8 +185,6 @@ void rcu_bh_qs(int cpu) { struct rcu_data *rdp = &per_cpu(rcu_bh_data, cpu); - rdp->passed_quiesce_gpnum = rdp->gpnum; - barrier(); if (rdp->passed_quiesce == 0) trace_rcu_grace_period("rcu_bh", rdp->gpnum, "cpuqs"); rdp->passed_quiesce = 1; @@ -899,12 +895,8 @@ static void __note_new_gpnum(struct rcu_state *rsp, struct rcu_node *rnp, struct */ rdp->gpnum = rnp->gpnum; trace_rcu_grace_period(rsp->name, rdp->gpnum, "cpustart"); - if (rnp->qsmask & rdp->grpmask) { - rdp->qs_pending = 1; - rdp->passed_quiesce = 0; - } else { - rdp->qs_pending = 0; - } + rdp->passed_quiesce = 0; + rdp->qs_pending = !!(rnp->qsmask & rdp->grpmask); zero_cpu_stall_ticks(rdp); } } @@ -984,10 +976,13 @@ __rcu_process_gp_end(struct rcu_state *rsp, struct rcu_node *rnp, struct rcu_dat * our behalf. Catch up with this state to avoid noting * spurious new grace periods. If another grace period * has started, then rnp->gpnum will have advanced, so - * we will detect this later on. + * we will detect this later on. Of course, any quiescent + * states we found for the old GP are now invalid. */ - if (ULONG_CMP_LT(rdp->gpnum, rdp->completed)) + if (ULONG_CMP_LT(rdp->gpnum, rdp->completed)) { rdp->gpnum = rdp->completed; + rdp->passed_quiesce = 0; + } /* * If RCU does not need a quiescent state from this CPU, @@ -1358,7 +1353,7 @@ rcu_report_qs_rnp(unsigned long mask, struct rcu_state *rsp, * based on quiescent states detected in an earlier grace period! */ static void -rcu_report_qs_rdp(int cpu, struct rcu_state *rsp, struct rcu_data *rdp, long lastgp) +rcu_report_qs_rdp(int cpu, struct rcu_state *rsp, struct rcu_data *rdp) { unsigned long flags; unsigned long mask; @@ -1366,7 +1361,8 @@ rcu_report_qs_rdp(int cpu, struct rcu_state *rsp, struct rcu_data *rdp, long las rnp = rdp->mynode; raw_spin_lock_irqsave(&rnp->lock, flags); - if (lastgp != rnp->gpnum || rnp->completed == rnp->gpnum) { + if (rdp->passed_quiesce == 0 || rdp->gpnum != rnp->gpnum || + rnp->completed == rnp->gpnum) { /* * The grace period in which this quiescent state was @@ -1425,7 +1421,7 @@ rcu_check_quiescent_state(struct rcu_state *rsp, struct rcu_data *rdp) * Tell RCU we are done (but rcu_report_qs_rdp() will be the * judge of that). */ - rcu_report_qs_rdp(rdp->cpu, rsp, rdp, rdp->passed_quiesce_gpnum); + rcu_report_qs_rdp(rdp->cpu, rsp, rdp); } #ifdef CONFIG_HOTPLUG_CPU @@ -2600,7 +2596,6 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp, int preemptible) rdp->completed = rnp->completed; rdp->passed_quiesce = 0; rdp->qs_pending = 0; - rdp->passed_quiesce_gpnum = rnp->gpnum - 1; trace_rcu_grace_period(rsp->name, rdp->gpnum, "cpuonl"); } raw_spin_unlock(&rnp->lock); /* irqs already disabled. */ diff --git a/kernel/rcutree.h b/kernel/rcutree.h index 8f0293ce1517..935dd4ca6816 100644 --- a/kernel/rcutree.h +++ b/kernel/rcutree.h @@ -246,8 +246,6 @@ struct rcu_data { /* in order to detect GP end. */ unsigned long gpnum; /* Highest gp number that this CPU */ /* is aware of having started. */ - unsigned long passed_quiesce_gpnum; - /* gpnum at time of quiescent state. */ bool passed_quiesce; /* User-mode/idle loop etc. */ bool qs_pending; /* Core waits for quiesc state. */ bool beenonline; /* CPU online at least once. */ diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index b4e8eb24a5f1..4734afbea73a 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -137,8 +137,6 @@ static void rcu_preempt_qs(int cpu) { struct rcu_data *rdp = &per_cpu(rcu_preempt_data, cpu); - rdp->passed_quiesce_gpnum = rdp->gpnum; - barrier(); if (rdp->passed_quiesce == 0) trace_rcu_grace_period("rcu_preempt", rdp->gpnum, "cpuqs"); rdp->passed_quiesce = 1; diff --git a/kernel/rcutree_trace.c b/kernel/rcutree_trace.c index f54f0ceda0cf..bd4df13d4afb 100644 --- a/kernel/rcutree_trace.c +++ b/kernel/rcutree_trace.c @@ -86,12 +86,11 @@ static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp) { if (!rdp->beenonline) return; - seq_printf(m, "%3d%cc=%lu g=%lu pq=%d pgp=%lu qp=%d", + seq_printf(m, "%3d%cc=%lu g=%lu pq=%d qp=%d", rdp->cpu, cpu_is_offline(rdp->cpu) ? '!' : ' ', rdp->completed, rdp->gpnum, - rdp->passed_quiesce, rdp->passed_quiesce_gpnum, - rdp->qs_pending); + rdp->passed_quiesce, rdp->qs_pending); seq_printf(m, " dt=%d/%llx/%d df=%lu", atomic_read(&rdp->dynticks->dynticks), rdp->dynticks->dynticks_nesting, @@ -150,12 +149,11 @@ static void print_one_rcu_data_csv(struct seq_file *m, struct rcu_data *rdp) { if (!rdp->beenonline) return; - seq_printf(m, "%d,%s,%lu,%lu,%d,%lu,%d", + seq_printf(m, "%d,%s,%lu,%lu,%d,%d", rdp->cpu, cpu_is_offline(rdp->cpu) ? "\"N\"" : "\"Y\"", rdp->completed, rdp->gpnum, - rdp->passed_quiesce, rdp->passed_quiesce_gpnum, - rdp->qs_pending); + rdp->passed_quiesce, rdp->qs_pending); seq_printf(m, ",%d,%llx,%d,%lu", atomic_read(&rdp->dynticks->dynticks), rdp->dynticks->dynticks_nesting, @@ -186,7 +184,7 @@ static int show_rcudata_csv(struct seq_file *m, void *unused) int cpu; struct rcu_state *rsp; - seq_puts(m, "\"CPU\",\"Online?\",\"c\",\"g\",\"pq\",\"pgp\",\"pq\","); + seq_puts(m, "\"CPU\",\"Online?\",\"c\",\"g\",\"pq\",\"pq\","); seq_puts(m, "\"dt\",\"dt nesting\",\"dt NMI nesting\",\"df\","); seq_puts(m, "\"of\",\"qll\",\"ql\",\"qs\""); #ifdef CONFIG_RCU_BOOST |