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@@ -25,39 +25,39 @@
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/*
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* Record the start of an expedited grace period.
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*/
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static void rcu_exp_gp_seq_start(struct rcu_state *rsp)
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static void rcu_exp_gp_seq_start(void)
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{
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rcu_seq_start(&rsp->expedited_sequence);
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rcu_seq_start(&rcu_state.expedited_sequence);
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}
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/*
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* Return then value that expedited-grace-period counter will have
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* at the end of the current grace period.
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*/
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static __maybe_unused unsigned long rcu_exp_gp_seq_endval(struct rcu_state *rsp)
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static __maybe_unused unsigned long rcu_exp_gp_seq_endval(void)
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{
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return rcu_seq_endval(&rsp->expedited_sequence);
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return rcu_seq_endval(&rcu_state.expedited_sequence);
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}
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/*
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* Record the end of an expedited grace period.
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*/
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static void rcu_exp_gp_seq_end(struct rcu_state *rsp)
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static void rcu_exp_gp_seq_end(void)
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{
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rcu_seq_end(&rsp->expedited_sequence);
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rcu_seq_end(&rcu_state.expedited_sequence);
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smp_mb(); /* Ensure that consecutive grace periods serialize. */
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}
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/*
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* Take a snapshot of the expedited-grace-period counter.
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*/
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static unsigned long rcu_exp_gp_seq_snap(struct rcu_state *rsp)
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static unsigned long rcu_exp_gp_seq_snap(void)
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{
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unsigned long s;
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smp_mb(); /* Caller's modifications seen first by other CPUs. */
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s = rcu_seq_snap(&rsp->expedited_sequence);
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trace_rcu_exp_grace_period(rsp->name, s, TPS("snap"));
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s = rcu_seq_snap(&rcu_state.expedited_sequence);
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trace_rcu_exp_grace_period(rcu_state.name, s, TPS("snap"));
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return s;
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}
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@@ -66,9 +66,9 @@ static unsigned long rcu_exp_gp_seq_snap(struct rcu_state *rsp)
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* if a full expedited grace period has elapsed since that snapshot
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* was taken.
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*/
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static bool rcu_exp_gp_seq_done(struct rcu_state *rsp, unsigned long s)
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static bool rcu_exp_gp_seq_done(unsigned long s)
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{
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return rcu_seq_done(&rsp->expedited_sequence, s);
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return rcu_seq_done(&rcu_state.expedited_sequence, s);
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}
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/*
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@@ -78,26 +78,26 @@ static bool rcu_exp_gp_seq_done(struct rcu_state *rsp, unsigned long s)
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* ever been online. This means that this function normally takes its
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* no-work-to-do fastpath.
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*/
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static void sync_exp_reset_tree_hotplug(struct rcu_state *rsp)
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static void sync_exp_reset_tree_hotplug(void)
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{
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bool done;
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unsigned long flags;
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unsigned long mask;
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unsigned long oldmask;
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int ncpus = smp_load_acquire(&rsp->ncpus); /* Order against locking. */
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int ncpus = smp_load_acquire(&rcu_state.ncpus); /* Order vs. locking. */
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struct rcu_node *rnp;
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struct rcu_node *rnp_up;
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/* If no new CPUs onlined since last time, nothing to do. */
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if (likely(ncpus == rsp->ncpus_snap))
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if (likely(ncpus == rcu_state.ncpus_snap))
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return;
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rsp->ncpus_snap = ncpus;
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rcu_state.ncpus_snap = ncpus;
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/*
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* Each pass through the following loop propagates newly onlined
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* CPUs for the current rcu_node structure up the rcu_node tree.
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*/
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rcu_for_each_leaf_node(rsp, rnp) {
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rcu_for_each_leaf_node(&rcu_state, rnp) {
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raw_spin_lock_irqsave_rcu_node(rnp, flags);
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if (rnp->expmaskinit == rnp->expmaskinitnext) {
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raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
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@@ -135,13 +135,13 @@ static void sync_exp_reset_tree_hotplug(struct rcu_state *rsp)
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* Reset the ->expmask values in the rcu_node tree in preparation for
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* a new expedited grace period.
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*/
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static void __maybe_unused sync_exp_reset_tree(struct rcu_state *rsp)
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static void __maybe_unused sync_exp_reset_tree(void)
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{
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unsigned long flags;
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struct rcu_node *rnp;
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sync_exp_reset_tree_hotplug(rsp);
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rcu_for_each_node_breadth_first(rsp, rnp) {
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sync_exp_reset_tree_hotplug();
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rcu_for_each_node_breadth_first(&rcu_state, rnp) {
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raw_spin_lock_irqsave_rcu_node(rnp, flags);
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WARN_ON_ONCE(rnp->expmask);
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rnp->expmask = rnp->expmaskinit;
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@@ -194,7 +194,7 @@ static bool sync_rcu_preempt_exp_done_unlocked(struct rcu_node *rnp)
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*
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* Caller must hold the specified rcu_node structure's ->lock.
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*/
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static void __rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp,
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static void __rcu_report_exp_rnp(struct rcu_node *rnp,
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bool wake, unsigned long flags)
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__releases(rnp->lock)
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{
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@@ -212,7 +212,7 @@ static void __rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp,
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raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
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if (wake) {
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smp_mb(); /* EGP done before wake_up(). */
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swake_up_one(&rsp->expedited_wq);
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swake_up_one(&rcu_state.expedited_wq);
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}
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break;
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}
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@@ -229,20 +229,19 @@ static void __rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp,
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* Report expedited quiescent state for specified node. This is a
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* lock-acquisition wrapper function for __rcu_report_exp_rnp().
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*/
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static void __maybe_unused rcu_report_exp_rnp(struct rcu_state *rsp,
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struct rcu_node *rnp, bool wake)
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static void __maybe_unused rcu_report_exp_rnp(struct rcu_node *rnp, bool wake)
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{
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unsigned long flags;
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raw_spin_lock_irqsave_rcu_node(rnp, flags);
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__rcu_report_exp_rnp(rsp, rnp, wake, flags);
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__rcu_report_exp_rnp(rnp, wake, flags);
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}
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/*
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* Report expedited quiescent state for multiple CPUs, all covered by the
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* specified leaf rcu_node structure.
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*/
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static void rcu_report_exp_cpu_mult(struct rcu_state *rsp, struct rcu_node *rnp,
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static void rcu_report_exp_cpu_mult(struct rcu_node *rnp,
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unsigned long mask, bool wake)
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{
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unsigned long flags;
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@@ -253,23 +252,23 @@ static void rcu_report_exp_cpu_mult(struct rcu_state *rsp, struct rcu_node *rnp,
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return;
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}
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rnp->expmask &= ~mask;
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__rcu_report_exp_rnp(rsp, rnp, wake, flags); /* Releases rnp->lock. */
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__rcu_report_exp_rnp(rnp, wake, flags); /* Releases rnp->lock. */
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}
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/*
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* Report expedited quiescent state for specified rcu_data (CPU).
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*/
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static void rcu_report_exp_rdp(struct rcu_state *rsp, struct rcu_data *rdp)
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static void rcu_report_exp_rdp(struct rcu_data *rdp)
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{
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WRITE_ONCE(rdp->deferred_qs, false);
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rcu_report_exp_cpu_mult(rsp, rdp->mynode, rdp->grpmask, true);
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rcu_report_exp_cpu_mult(rdp->mynode, rdp->grpmask, true);
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}
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/* Common code for work-done checking. */
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static bool sync_exp_work_done(struct rcu_state *rsp, unsigned long s)
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static bool sync_exp_work_done(unsigned long s)
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{
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if (rcu_exp_gp_seq_done(rsp, s)) {
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trace_rcu_exp_grace_period(rsp->name, s, TPS("done"));
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if (rcu_exp_gp_seq_done(s)) {
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trace_rcu_exp_grace_period(rcu_state.name, s, TPS("done"));
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/* Ensure test happens before caller kfree(). */
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smp_mb__before_atomic(); /* ^^^ */
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return true;
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@@ -284,7 +283,7 @@ static bool sync_exp_work_done(struct rcu_state *rsp, unsigned long s)
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* with the mutex held, indicating that the caller must actually do the
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* expedited grace period.
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*/
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static bool exp_funnel_lock(struct rcu_state *rsp, unsigned long s)
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static bool exp_funnel_lock(unsigned long s)
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{
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struct rcu_data *rdp = per_cpu_ptr(&rcu_data, raw_smp_processor_id());
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struct rcu_node *rnp = rdp->mynode;
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@@ -294,18 +293,18 @@ static bool exp_funnel_lock(struct rcu_state *rsp, unsigned long s)
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if (ULONG_CMP_LT(READ_ONCE(rnp->exp_seq_rq), s) &&
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(rnp == rnp_root ||
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ULONG_CMP_LT(READ_ONCE(rnp_root->exp_seq_rq), s)) &&
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mutex_trylock(&rsp->exp_mutex))
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mutex_trylock(&rcu_state.exp_mutex))
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goto fastpath;
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/*
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* Each pass through the following loop works its way up
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* the rcu_node tree, returning if others have done the work or
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* otherwise falls through to acquire rsp->exp_mutex. The mapping
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* otherwise falls through to acquire ->exp_mutex. The mapping
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* from CPU to rcu_node structure can be inexact, as it is just
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* promoting locality and is not strictly needed for correctness.
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*/
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for (; rnp != NULL; rnp = rnp->parent) {
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if (sync_exp_work_done(rsp, s))
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if (sync_exp_work_done(s))
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return true;
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/* Work not done, either wait here or go up. */
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@@ -314,26 +313,26 @@ static bool exp_funnel_lock(struct rcu_state *rsp, unsigned long s)
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/* Someone else doing GP, so wait for them. */
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spin_unlock(&rnp->exp_lock);
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trace_rcu_exp_funnel_lock(rsp->name, rnp->level,
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trace_rcu_exp_funnel_lock(rcu_state.name, rnp->level,
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rnp->grplo, rnp->grphi,
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TPS("wait"));
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wait_event(rnp->exp_wq[rcu_seq_ctr(s) & 0x3],
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sync_exp_work_done(rsp, s));
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sync_exp_work_done(s));
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return true;
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}
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rnp->exp_seq_rq = s; /* Followers can wait on us. */
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spin_unlock(&rnp->exp_lock);
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trace_rcu_exp_funnel_lock(rsp->name, rnp->level, rnp->grplo,
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rnp->grphi, TPS("nxtlvl"));
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trace_rcu_exp_funnel_lock(rcu_state.name, rnp->level,
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rnp->grplo, rnp->grphi, TPS("nxtlvl"));
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}
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mutex_lock(&rsp->exp_mutex);
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mutex_lock(&rcu_state.exp_mutex);
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fastpath:
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if (sync_exp_work_done(rsp, s)) {
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mutex_unlock(&rsp->exp_mutex);
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if (sync_exp_work_done(s)) {
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mutex_unlock(&rcu_state.exp_mutex);
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return true;
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}
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rcu_exp_gp_seq_start(rsp);
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trace_rcu_exp_grace_period(rsp->name, s, TPS("start"));
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rcu_exp_gp_seq_start();
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trace_rcu_exp_grace_period(rcu_state.name, s, TPS("start"));
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return false;
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}
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@@ -352,7 +351,6 @@ static void sync_rcu_exp_select_node_cpus(struct work_struct *wp)
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struct rcu_exp_work *rewp =
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container_of(wp, struct rcu_exp_work, rew_work);
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struct rcu_node *rnp = container_of(rewp, struct rcu_node, rew);
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struct rcu_state *rsp = rewp->rew_rsp;
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func = rewp->rew_func;
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raw_spin_lock_irqsave_rcu_node(rnp, flags);
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@@ -400,7 +398,7 @@ retry_ipi:
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mask_ofl_test |= mask;
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continue;
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}
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ret = smp_call_function_single(cpu, func, rsp, 0);
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ret = smp_call_function_single(cpu, func, NULL, 0);
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if (!ret) {
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mask_ofl_ipi &= ~mask;
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continue;
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@@ -411,7 +409,7 @@ retry_ipi:
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(rnp->expmask & mask)) {
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/* Online, so delay for a bit and try again. */
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raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
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trace_rcu_exp_grace_period(rsp->name, rcu_exp_gp_seq_endval(rsp), TPS("selectofl"));
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trace_rcu_exp_grace_period(rcu_state.name, rcu_exp_gp_seq_endval(), TPS("selectofl"));
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schedule_timeout_uninterruptible(1);
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goto retry_ipi;
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}
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|
|
@@ -423,33 +421,31 @@ retry_ipi:
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/* Report quiescent states for those that went offline. */
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mask_ofl_test |= mask_ofl_ipi;
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if (mask_ofl_test)
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|
|
|
|
rcu_report_exp_cpu_mult(rsp, rnp, mask_ofl_test, false);
|
|
|
|
|
rcu_report_exp_cpu_mult(rnp, mask_ofl_test, false);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Select the nodes that the upcoming expedited grace period needs
|
|
|
|
|
* to wait for.
|
|
|
|
|
*/
|
|
|
|
|
static void sync_rcu_exp_select_cpus(struct rcu_state *rsp,
|
|
|
|
|
smp_call_func_t func)
|
|
|
|
|
static void sync_rcu_exp_select_cpus(smp_call_func_t func)
|
|
|
|
|
{
|
|
|
|
|
int cpu;
|
|
|
|
|
struct rcu_node *rnp;
|
|
|
|
|
|
|
|
|
|
trace_rcu_exp_grace_period(rsp->name, rcu_exp_gp_seq_endval(rsp), TPS("reset"));
|
|
|
|
|
sync_exp_reset_tree(rsp);
|
|
|
|
|
trace_rcu_exp_grace_period(rsp->name, rcu_exp_gp_seq_endval(rsp), TPS("select"));
|
|
|
|
|
trace_rcu_exp_grace_period(rcu_state.name, rcu_exp_gp_seq_endval(), TPS("reset"));
|
|
|
|
|
sync_exp_reset_tree();
|
|
|
|
|
trace_rcu_exp_grace_period(rcu_state.name, rcu_exp_gp_seq_endval(), TPS("select"));
|
|
|
|
|
|
|
|
|
|
/* Schedule work for each leaf rcu_node structure. */
|
|
|
|
|
rcu_for_each_leaf_node(rsp, rnp) {
|
|
|
|
|
rcu_for_each_leaf_node(&rcu_state, rnp) {
|
|
|
|
|
rnp->exp_need_flush = false;
|
|
|
|
|
if (!READ_ONCE(rnp->expmask))
|
|
|
|
|
continue; /* Avoid early boot non-existent wq. */
|
|
|
|
|
rnp->rew.rew_func = func;
|
|
|
|
|
rnp->rew.rew_rsp = rsp;
|
|
|
|
|
if (!READ_ONCE(rcu_par_gp_wq) ||
|
|
|
|
|
rcu_scheduler_active != RCU_SCHEDULER_RUNNING ||
|
|
|
|
|
rcu_is_last_leaf_node(rsp, rnp)) {
|
|
|
|
|
rcu_is_last_leaf_node(&rcu_state, rnp)) {
|
|
|
|
|
/* No workqueues yet or last leaf, do direct call. */
|
|
|
|
|
sync_rcu_exp_select_node_cpus(&rnp->rew.rew_work);
|
|
|
|
|
continue;
|
|
|
|
|
@@ -466,12 +462,12 @@ static void sync_rcu_exp_select_cpus(struct rcu_state *rsp,
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* Wait for workqueue jobs (if any) to complete. */
|
|
|
|
|
rcu_for_each_leaf_node(rsp, rnp)
|
|
|
|
|
rcu_for_each_leaf_node(&rcu_state, rnp)
|
|
|
|
|
if (rnp->exp_need_flush)
|
|
|
|
|
flush_work(&rnp->rew.rew_work);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static void synchronize_sched_expedited_wait(struct rcu_state *rsp)
|
|
|
|
|
static void synchronize_sched_expedited_wait(void)
|
|
|
|
|
{
|
|
|
|
|
int cpu;
|
|
|
|
|
unsigned long jiffies_stall;
|
|
|
|
|
@@ -482,13 +478,13 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp)
|
|
|
|
|
struct rcu_node *rnp_root = rcu_get_root();
|
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
|
|
trace_rcu_exp_grace_period(rsp->name, rcu_exp_gp_seq_endval(rsp), TPS("startwait"));
|
|
|
|
|
trace_rcu_exp_grace_period(rcu_state.name, rcu_exp_gp_seq_endval(), TPS("startwait"));
|
|
|
|
|
jiffies_stall = rcu_jiffies_till_stall_check();
|
|
|
|
|
jiffies_start = jiffies;
|
|
|
|
|
|
|
|
|
|
for (;;) {
|
|
|
|
|
ret = swait_event_timeout_exclusive(
|
|
|
|
|
rsp->expedited_wq,
|
|
|
|
|
rcu_state.expedited_wq,
|
|
|
|
|
sync_rcu_preempt_exp_done_unlocked(rnp_root),
|
|
|
|
|
jiffies_stall);
|
|
|
|
|
if (ret > 0 || sync_rcu_preempt_exp_done_unlocked(rnp_root))
|
|
|
|
|
@@ -498,9 +494,9 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp)
|
|
|
|
|
continue;
|
|
|
|
|
panic_on_rcu_stall();
|
|
|
|
|
pr_err("INFO: %s detected expedited stalls on CPUs/tasks: {",
|
|
|
|
|
rsp->name);
|
|
|
|
|
rcu_state.name);
|
|
|
|
|
ndetected = 0;
|
|
|
|
|
rcu_for_each_leaf_node(rsp, rnp) {
|
|
|
|
|
rcu_for_each_leaf_node(&rcu_state, rnp) {
|
|
|
|
|
ndetected += rcu_print_task_exp_stall(rnp);
|
|
|
|
|
for_each_leaf_node_possible_cpu(rnp, cpu) {
|
|
|
|
|
struct rcu_data *rdp;
|
|
|
|
|
@@ -517,11 +513,11 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp)
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
pr_cont(" } %lu jiffies s: %lu root: %#lx/%c\n",
|
|
|
|
|
jiffies - jiffies_start, rsp->expedited_sequence,
|
|
|
|
|
jiffies - jiffies_start, rcu_state.expedited_sequence,
|
|
|
|
|
rnp_root->expmask, ".T"[!!rnp_root->exp_tasks]);
|
|
|
|
|
if (ndetected) {
|
|
|
|
|
pr_err("blocking rcu_node structures:");
|
|
|
|
|
rcu_for_each_node_breadth_first(rsp, rnp) {
|
|
|
|
|
rcu_for_each_node_breadth_first(&rcu_state, rnp) {
|
|
|
|
|
if (rnp == rnp_root)
|
|
|
|
|
continue; /* printed unconditionally */
|
|
|
|
|
if (sync_rcu_preempt_exp_done_unlocked(rnp))
|
|
|
|
|
@@ -533,7 +529,7 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp)
|
|
|
|
|
}
|
|
|
|
|
pr_cont("\n");
|
|
|
|
|
}
|
|
|
|
|
rcu_for_each_leaf_node(rsp, rnp) {
|
|
|
|
|
rcu_for_each_leaf_node(&rcu_state, rnp) {
|
|
|
|
|
for_each_leaf_node_possible_cpu(rnp, cpu) {
|
|
|
|
|
mask = leaf_node_cpu_bit(rnp, cpu);
|
|
|
|
|
if (!(rnp->expmask & mask))
|
|
|
|
|
@@ -551,21 +547,21 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp)
|
|
|
|
|
* grace period. Also update all the ->exp_seq_rq counters as needed
|
|
|
|
|
* in order to avoid counter-wrap problems.
|
|
|
|
|
*/
|
|
|
|
|
static void rcu_exp_wait_wake(struct rcu_state *rsp, unsigned long s)
|
|
|
|
|
static void rcu_exp_wait_wake(unsigned long s)
|
|
|
|
|
{
|
|
|
|
|
struct rcu_node *rnp;
|
|
|
|
|
|
|
|
|
|
synchronize_sched_expedited_wait(rsp);
|
|
|
|
|
rcu_exp_gp_seq_end(rsp);
|
|
|
|
|
trace_rcu_exp_grace_period(rsp->name, s, TPS("end"));
|
|
|
|
|
synchronize_sched_expedited_wait();
|
|
|
|
|
rcu_exp_gp_seq_end();
|
|
|
|
|
trace_rcu_exp_grace_period(rcu_state.name, s, TPS("end"));
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Switch over to wakeup mode, allowing the next GP, but -only- the
|
|
|
|
|
* next GP, to proceed.
|
|
|
|
|
*/
|
|
|
|
|
mutex_lock(&rsp->exp_wake_mutex);
|
|
|
|
|
mutex_lock(&rcu_state.exp_wake_mutex);
|
|
|
|
|
|
|
|
|
|
rcu_for_each_node_breadth_first(rsp, rnp) {
|
|
|
|
|
rcu_for_each_node_breadth_first(&rcu_state, rnp) {
|
|
|
|
|
if (ULONG_CMP_LT(READ_ONCE(rnp->exp_seq_rq), s)) {
|
|
|
|
|
spin_lock(&rnp->exp_lock);
|
|
|
|
|
/* Recheck, avoid hang in case someone just arrived. */
|
|
|
|
|
@@ -574,24 +570,23 @@ static void rcu_exp_wait_wake(struct rcu_state *rsp, unsigned long s)
|
|
|
|
|
spin_unlock(&rnp->exp_lock);
|
|
|
|
|
}
|
|
|
|
|
smp_mb(); /* All above changes before wakeup. */
|
|
|
|
|
wake_up_all(&rnp->exp_wq[rcu_seq_ctr(rsp->expedited_sequence) & 0x3]);
|
|
|
|
|
wake_up_all(&rnp->exp_wq[rcu_seq_ctr(rcu_state.expedited_sequence) & 0x3]);
|
|
|
|
|
}
|
|
|
|
|
trace_rcu_exp_grace_period(rsp->name, s, TPS("endwake"));
|
|
|
|
|
mutex_unlock(&rsp->exp_wake_mutex);
|
|
|
|
|
trace_rcu_exp_grace_period(rcu_state.name, s, TPS("endwake"));
|
|
|
|
|
mutex_unlock(&rcu_state.exp_wake_mutex);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Common code to drive an expedited grace period forward, used by
|
|
|
|
|
* workqueues and mid-boot-time tasks.
|
|
|
|
|
*/
|
|
|
|
|
static void rcu_exp_sel_wait_wake(struct rcu_state *rsp,
|
|
|
|
|
smp_call_func_t func, unsigned long s)
|
|
|
|
|
static void rcu_exp_sel_wait_wake(smp_call_func_t func, unsigned long s)
|
|
|
|
|
{
|
|
|
|
|
/* Initialize the rcu_node tree in preparation for the wait. */
|
|
|
|
|
sync_rcu_exp_select_cpus(rsp, func);
|
|
|
|
|
sync_rcu_exp_select_cpus(func);
|
|
|
|
|
|
|
|
|
|
/* Wait and clean up, including waking everyone. */
|
|
|
|
|
rcu_exp_wait_wake(rsp, s);
|
|
|
|
|
rcu_exp_wait_wake(s);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
@@ -602,15 +597,14 @@ static void wait_rcu_exp_gp(struct work_struct *wp)
|
|
|
|
|
struct rcu_exp_work *rewp;
|
|
|
|
|
|
|
|
|
|
rewp = container_of(wp, struct rcu_exp_work, rew_work);
|
|
|
|
|
rcu_exp_sel_wait_wake(rewp->rew_rsp, rewp->rew_func, rewp->rew_s);
|
|
|
|
|
rcu_exp_sel_wait_wake(rewp->rew_func, rewp->rew_s);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Given an rcu_state pointer and a smp_call_function() handler, kick
|
|
|
|
|
* off the specified flavor of expedited grace period.
|
|
|
|
|
*/
|
|
|
|
|
static void _synchronize_rcu_expedited(struct rcu_state *rsp,
|
|
|
|
|
smp_call_func_t func)
|
|
|
|
|
static void _synchronize_rcu_expedited(smp_call_func_t func)
|
|
|
|
|
{
|
|
|
|
|
struct rcu_data *rdp;
|
|
|
|
|
struct rcu_exp_work rew;
|
|
|
|
|
@@ -624,18 +618,17 @@ static void _synchronize_rcu_expedited(struct rcu_state *rsp,
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* Take a snapshot of the sequence number. */
|
|
|
|
|
s = rcu_exp_gp_seq_snap(rsp);
|
|
|
|
|
if (exp_funnel_lock(rsp, s))
|
|
|
|
|
s = rcu_exp_gp_seq_snap();
|
|
|
|
|
if (exp_funnel_lock(s))
|
|
|
|
|
return; /* Someone else did our work for us. */
|
|
|
|
|
|
|
|
|
|
/* Ensure that load happens before action based on it. */
|
|
|
|
|
if (unlikely(rcu_scheduler_active == RCU_SCHEDULER_INIT)) {
|
|
|
|
|
/* Direct call during scheduler init and early_initcalls(). */
|
|
|
|
|
rcu_exp_sel_wait_wake(rsp, func, s);
|
|
|
|
|
rcu_exp_sel_wait_wake(func, s);
|
|
|
|
|
} else {
|
|
|
|
|
/* Marshall arguments & schedule the expedited grace period. */
|
|
|
|
|
rew.rew_func = func;
|
|
|
|
|
rew.rew_rsp = rsp;
|
|
|
|
|
rew.rew_s = s;
|
|
|
|
|
INIT_WORK_ONSTACK(&rew.rew_work, wait_rcu_exp_gp);
|
|
|
|
|
queue_work(rcu_gp_wq, &rew.rew_work);
|
|
|
|
|
@@ -645,11 +638,11 @@ static void _synchronize_rcu_expedited(struct rcu_state *rsp,
|
|
|
|
|
rdp = per_cpu_ptr(&rcu_data, raw_smp_processor_id());
|
|
|
|
|
rnp = rcu_get_root();
|
|
|
|
|
wait_event(rnp->exp_wq[rcu_seq_ctr(s) & 0x3],
|
|
|
|
|
sync_exp_work_done(rsp, s));
|
|
|
|
|
sync_exp_work_done(s));
|
|
|
|
|
smp_mb(); /* Workqueue actions happen before return. */
|
|
|
|
|
|
|
|
|
|
/* Let the next expedited grace period start. */
|
|
|
|
|
mutex_unlock(&rsp->exp_mutex);
|
|
|
|
|
mutex_unlock(&rcu_state.exp_mutex);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
#ifdef CONFIG_PREEMPT_RCU
|
|
|
|
|
@@ -661,10 +654,9 @@ static void _synchronize_rcu_expedited(struct rcu_state *rsp,
|
|
|
|
|
* ->expmask fields in the rcu_node tree. Otherwise, immediately
|
|
|
|
|
* report the quiescent state.
|
|
|
|
|
*/
|
|
|
|
|
static void sync_rcu_exp_handler(void *info)
|
|
|
|
|
static void sync_rcu_exp_handler(void *unused)
|
|
|
|
|
{
|
|
|
|
|
unsigned long flags;
|
|
|
|
|
struct rcu_state *rsp = info;
|
|
|
|
|
struct rcu_data *rdp = this_cpu_ptr(&rcu_data);
|
|
|
|
|
struct rcu_node *rnp = rdp->mynode;
|
|
|
|
|
struct task_struct *t = current;
|
|
|
|
|
@@ -677,7 +669,7 @@ static void sync_rcu_exp_handler(void *info)
|
|
|
|
|
if (!t->rcu_read_lock_nesting) {
|
|
|
|
|
if (!(preempt_count() & (PREEMPT_MASK | SOFTIRQ_MASK)) ||
|
|
|
|
|
rcu_dynticks_curr_cpu_in_eqs()) {
|
|
|
|
|
rcu_report_exp_rdp(rsp, rdp);
|
|
|
|
|
rcu_report_exp_rdp(rdp);
|
|
|
|
|
} else {
|
|
|
|
|
rdp->deferred_qs = true;
|
|
|
|
|
resched_cpu(rdp->cpu);
|
|
|
|
|
@@ -756,8 +748,6 @@ static void sync_sched_exp_online_cleanup(int cpu)
|
|
|
|
|
*/
|
|
|
|
|
void synchronize_rcu_expedited(void)
|
|
|
|
|
{
|
|
|
|
|
struct rcu_state *rsp = &rcu_state;
|
|
|
|
|
|
|
|
|
|
RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map) ||
|
|
|
|
|
lock_is_held(&rcu_lock_map) ||
|
|
|
|
|
lock_is_held(&rcu_sched_lock_map),
|
|
|
|
|
@@ -765,7 +755,7 @@ void synchronize_rcu_expedited(void)
|
|
|
|
|
|
|
|
|
|
if (rcu_scheduler_active == RCU_SCHEDULER_INACTIVE)
|
|
|
|
|
return;
|
|
|
|
|
_synchronize_rcu_expedited(rsp, sync_rcu_exp_handler);
|
|
|
|
|
_synchronize_rcu_expedited(sync_rcu_exp_handler);
|
|
|
|
|
}
|
|
|
|
|
EXPORT_SYMBOL_GPL(synchronize_rcu_expedited);
|
|
|
|
|
|
|
|
|
|
@@ -783,7 +773,7 @@ static void sync_sched_exp_handler(void *unused)
|
|
|
|
|
__this_cpu_read(rcu_data.cpu_no_qs.b.exp))
|
|
|
|
|
return;
|
|
|
|
|
if (rcu_is_cpu_rrupt_from_idle()) {
|
|
|
|
|
rcu_report_exp_rdp(&rcu_state, this_cpu_ptr(&rcu_data));
|
|
|
|
|
rcu_report_exp_rdp(this_cpu_ptr(&rcu_data));
|
|
|
|
|
return;
|
|
|
|
|
}
|
|
|
|
|
__this_cpu_write(rcu_data.cpu_no_qs.b.exp, true);
|
|
|
|
|
@@ -798,13 +788,12 @@ static void sync_sched_exp_online_cleanup(int cpu)
|
|
|
|
|
struct rcu_data *rdp;
|
|
|
|
|
int ret;
|
|
|
|
|
struct rcu_node *rnp;
|
|
|
|
|
struct rcu_state *rsp = &rcu_state;
|
|
|
|
|
|
|
|
|
|
rdp = per_cpu_ptr(&rcu_data, cpu);
|
|
|
|
|
rnp = rdp->mynode;
|
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if (!(READ_ONCE(rnp->expmask) & rdp->grpmask))
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return;
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ret = smp_call_function_single(cpu, sync_sched_exp_handler, rsp, 0);
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ret = smp_call_function_single(cpu, sync_sched_exp_handler, NULL, 0);
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WARN_ON_ONCE(ret);
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}
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@@ -831,8 +820,6 @@ static int rcu_blocking_is_gp(void)
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/* PREEMPT=n implementation of synchronize_rcu_expedited(). */
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void synchronize_rcu_expedited(void)
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{
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struct rcu_state *rsp = &rcu_state;
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RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map) ||
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lock_is_held(&rcu_lock_map) ||
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lock_is_held(&rcu_sched_lock_map),
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@@ -842,7 +829,7 @@ void synchronize_rcu_expedited(void)
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if (rcu_blocking_is_gp())
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return;
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_synchronize_rcu_expedited(rsp, sync_sched_exp_handler);
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_synchronize_rcu_expedited(sync_sched_exp_handler);
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}
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EXPORT_SYMBOL_GPL(synchronize_rcu_expedited);
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