diff options
Diffstat (limited to 'kernel/rcu/tree.c')
| -rw-r--r-- | kernel/rcu/tree.c | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index dd081987a8e..a6205a05b5e 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -1133,8 +1133,10 @@ rcu_start_future_gp(struct rcu_node *rnp, struct rcu_data *rdp) * hold it, acquire the root rcu_node structure's lock in order to * start one (if needed). */ - if (rnp != rnp_root) + if (rnp != rnp_root) { raw_spin_lock(&rnp_root->lock); + smp_mb__after_unlock_lock(); + } /* * Get a new grace-period number. If there really is no grace @@ -1354,6 +1356,7 @@ static void note_gp_changes(struct rcu_state *rsp, struct rcu_data *rdp) local_irq_restore(flags); return; } + smp_mb__after_unlock_lock(); __note_gp_changes(rsp, rnp, rdp); raw_spin_unlock_irqrestore(&rnp->lock, flags); } @@ -1368,6 +1371,7 @@ static int rcu_gp_init(struct rcu_state *rsp) rcu_bind_gp_kthread(); raw_spin_lock_irq(&rnp->lock); + smp_mb__after_unlock_lock(); if (rsp->gp_flags == 0) { /* Spurious wakeup, tell caller to go back to sleep. */ raw_spin_unlock_irq(&rnp->lock); @@ -1409,6 +1413,7 @@ static int rcu_gp_init(struct rcu_state *rsp) */ rcu_for_each_node_breadth_first(rsp, rnp) { raw_spin_lock_irq(&rnp->lock); + smp_mb__after_unlock_lock(); rdp = this_cpu_ptr(rsp->rda); rcu_preempt_check_blocked_tasks(rnp); rnp->qsmask = rnp->qsmaskinit; @@ -1463,6 +1468,7 @@ static int rcu_gp_fqs(struct rcu_state *rsp, int fqs_state_in) /* Clear flag to prevent immediate re-entry. */ if (ACCESS_ONCE(rsp->gp_flags) & RCU_GP_FLAG_FQS) { raw_spin_lock_irq(&rnp->lock); + smp_mb__after_unlock_lock(); rsp->gp_flags &= ~RCU_GP_FLAG_FQS; raw_spin_unlock_irq(&rnp->lock); } @@ -1480,6 +1486,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp) struct rcu_node *rnp = rcu_get_root(rsp); raw_spin_lock_irq(&rnp->lock); + smp_mb__after_unlock_lock(); gp_duration = jiffies - rsp->gp_start; if (gp_duration > rsp->gp_max) rsp->gp_max = gp_duration; @@ -1505,6 +1512,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp) */ rcu_for_each_node_breadth_first(rsp, rnp) { raw_spin_lock_irq(&rnp->lock); + smp_mb__after_unlock_lock(); ACCESS_ONCE(rnp->completed) = rsp->gpnum; rdp = this_cpu_ptr(rsp->rda); if (rnp == rdp->mynode) @@ -1515,6 +1523,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp) } rnp = rcu_get_root(rsp); raw_spin_lock_irq(&rnp->lock); + smp_mb__after_unlock_lock(); rcu_nocb_gp_set(rnp, nocb); rsp->completed = rsp->gpnum; /* Declare grace period done. */ @@ -1749,6 +1758,7 @@ rcu_report_qs_rnp(unsigned long mask, struct rcu_state *rsp, rnp_c = rnp; rnp = rnp->parent; raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); WARN_ON_ONCE(rnp_c->qsmask); } @@ -1778,6 +1788,7 @@ rcu_report_qs_rdp(int cpu, struct rcu_state *rsp, struct rcu_data *rdp) rnp = rdp->mynode; raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); if (rdp->passed_quiesce == 0 || rdp->gpnum != rnp->gpnum || rnp->completed == rnp->gpnum) { @@ -1992,6 +2003,7 @@ static void rcu_cleanup_dead_cpu(int cpu, struct rcu_state *rsp) mask = rdp->grpmask; /* rnp->grplo is constant. */ do { raw_spin_lock(&rnp->lock); /* irqs already disabled. */ + smp_mb__after_unlock_lock(); rnp->qsmaskinit &= ~mask; if (rnp->qsmaskinit != 0) { if (rnp != rdp->mynode) @@ -2202,6 +2214,7 @@ static void force_qs_rnp(struct rcu_state *rsp, cond_resched(); mask = 0; raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); if (!rcu_gp_in_progress(rsp)) { raw_spin_unlock_irqrestore(&rnp->lock, flags); return; @@ -2231,6 +2244,7 @@ static void force_qs_rnp(struct rcu_state *rsp, rnp = rcu_get_root(rsp); if (rnp->qsmask == 0) { raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); rcu_initiate_boost(rnp, flags); /* releases rnp->lock. */ } } @@ -2263,6 +2277,7 @@ static void force_quiescent_state(struct rcu_state *rsp) /* Reached the root of the rcu_node tree, acquire lock. */ raw_spin_lock_irqsave(&rnp_old->lock, flags); + smp_mb__after_unlock_lock(); raw_spin_unlock(&rnp_old->fqslock); if (ACCESS_ONCE(rsp->gp_flags) & RCU_GP_FLAG_FQS) { rsp->n_force_qs_lh++; @@ -2378,6 +2393,7 @@ static void __call_rcu_core(struct rcu_state *rsp, struct rcu_data *rdp, struct rcu_node *rnp_root = rcu_get_root(rsp); raw_spin_lock(&rnp_root->lock); + smp_mb__after_unlock_lock(); rcu_start_gp(rsp); raw_spin_unlock(&rnp_root->lock); } else { |