From 88d1bead858d88cdda92ed8f3388eea8ee3a9675 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Wed, 4 Jul 2018 14:45:00 -0700 Subject: [PATCH] rcu: Remove rcu_data structure's ->rsp field Now that there is only one rcu_state structure, there is no need for the rcu_data structure to indicate which it corresponds to. This commit therefore removes the rcu_data structure's ->rsp field, replacing all remaining uses of it with &rcu_state. Signed-off-by: Paul E. McKenney --- kernel/rcu/tree.c | 28 +++++++++++++-------------- kernel/rcu/tree.h | 1 - kernel/rcu/tree_plugin.h | 42 ++++++++++++++++++++-------------------- 3 files changed, 34 insertions(+), 37 deletions(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 0465a85a40e1..aeff9024bb6c 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -1070,7 +1070,7 @@ static int dyntick_save_progress_counter(struct rcu_data *rdp) { rdp->dynticks_snap = rcu_dynticks_snap(rdp->dynticks); if (rcu_dynticks_in_eqs(rdp->dynticks_snap)) { - trace_rcu_fqs(rdp->rsp->name, rdp->gp_seq, rdp->cpu, TPS("dti")); + trace_rcu_fqs(rcu_state.name, rdp->gp_seq, rdp->cpu, TPS("dti")); rcu_gpnum_ovf(rdp->mynode, rdp); return 1; } @@ -1120,7 +1120,7 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp) * of the current RCU grace period. */ if (rcu_dynticks_in_eqs_since(rdp->dynticks, rdp->dynticks_snap)) { - trace_rcu_fqs(rdp->rsp->name, rdp->gp_seq, rdp->cpu, TPS("dti")); + trace_rcu_fqs(rcu_state.name, rdp->gp_seq, rdp->cpu, TPS("dti")); rdp->dynticks_fqs++; rcu_gpnum_ovf(rnp, rdp); return 1; @@ -1134,20 +1134,20 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp) */ jtsq = jiffies_till_sched_qs; ruqp = per_cpu_ptr(&rcu_dynticks.rcu_urgent_qs, rdp->cpu); - if (time_after(jiffies, rdp->rsp->gp_start + jtsq) && + if (time_after(jiffies, rcu_state.gp_start + jtsq) && READ_ONCE(rdp->rcu_qs_ctr_snap) != per_cpu(rcu_dynticks.rcu_qs_ctr, rdp->cpu) && rcu_seq_current(&rdp->gp_seq) == rnp->gp_seq && !rdp->gpwrap) { - trace_rcu_fqs(rdp->rsp->name, rdp->gp_seq, rdp->cpu, TPS("rqc")); + trace_rcu_fqs(rcu_state.name, rdp->gp_seq, rdp->cpu, TPS("rqc")); rcu_gpnum_ovf(rnp, rdp); return 1; - } else if (time_after(jiffies, rdp->rsp->gp_start + jtsq)) { + } else if (time_after(jiffies, rcu_state.gp_start + jtsq)) { /* Load rcu_qs_ctr before store to rcu_urgent_qs. */ smp_store_release(ruqp, true); } /* If waiting too long on an offline CPU, complain. */ if (!(rdp->grpmask & rcu_rnp_online_cpus(rnp)) && - time_after(jiffies, rdp->rsp->gp_start + HZ)) { + time_after(jiffies, rcu_state.gp_start + HZ)) { bool onl; struct rcu_node *rnp1; @@ -1185,12 +1185,12 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp) */ rnhqp = &per_cpu(rcu_dynticks.rcu_need_heavy_qs, rdp->cpu); if (!READ_ONCE(*rnhqp) && - (time_after(jiffies, rdp->rsp->gp_start + jtsq) || - time_after(jiffies, rdp->rsp->jiffies_resched))) { + (time_after(jiffies, rcu_state.gp_start + jtsq) || + time_after(jiffies, rcu_state.jiffies_resched))) { WRITE_ONCE(*rnhqp, true); /* Store rcu_need_heavy_qs before rcu_urgent_qs. */ smp_store_release(ruqp, true); - rdp->rsp->jiffies_resched += jtsq; /* Re-enable beating. */ + rcu_state.jiffies_resched += jtsq; /* Re-enable beating. */ } /* @@ -1199,7 +1199,7 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp) * see if the CPU is getting hammered with interrupts, but only * once per grace period, just to keep the IPIs down to a dull roar. */ - if (jiffies - rdp->rsp->gp_start > rcu_jiffies_till_stall_check() / 2) { + if (jiffies - rcu_state.gp_start > rcu_jiffies_till_stall_check() / 2) { resched_cpu(rdp->cpu); if (IS_ENABLED(CONFIG_IRQ_WORK) && !rdp->rcu_iw_pending && rdp->rcu_iw_gp_seq != rnp->gp_seq && @@ -1526,7 +1526,7 @@ void rcu_cpu_stall_reset(void) static void trace_rcu_this_gp(struct rcu_node *rnp, struct rcu_data *rdp, unsigned long gp_seq_req, const char *s) { - trace_rcu_future_grace_period(rdp->rsp->name, rnp->gp_seq, gp_seq_req, + trace_rcu_future_grace_period(rcu_state.name, rnp->gp_seq, gp_seq_req, rnp->level, rnp->grplo, rnp->grphi, s); } @@ -1550,7 +1550,7 @@ static bool rcu_start_this_gp(struct rcu_node *rnp_start, struct rcu_data *rdp, unsigned long gp_seq_req) { bool ret = false; - struct rcu_state *rsp = rdp->rsp; + struct rcu_state *rsp = &rcu_state; struct rcu_node *rnp; /* @@ -3167,8 +3167,7 @@ static void _rcu_barrier_trace(const char *s, int cpu, unsigned long done) */ static void rcu_barrier_callback(struct rcu_head *rhp) { - struct rcu_data *rdp = container_of(rhp, struct rcu_data, barrier_head); - struct rcu_state *rsp = rdp->rsp; + struct rcu_state *rsp = &rcu_state; if (atomic_dec_and_test(&rsp->barrier_cpu_count)) { _rcu_barrier_trace(TPS("LastCB"), -1, rsp->barrier_sequence); @@ -3365,7 +3364,6 @@ rcu_boot_init_percpu_data(int cpu) rdp->rcu_onl_gp_seq = rcu_state.gp_seq; rdp->rcu_onl_gp_flags = RCU_GP_CLEANED; rdp->cpu = cpu; - rdp->rsp = &rcu_state; rcu_boot_init_nocb_percpu_data(rdp); } diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index b21d79bdab23..6f1b1a3fc23d 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -265,7 +265,6 @@ struct rcu_data { short rcu_onl_gp_flags; /* ->gp_flags at last online. */ int cpu; - struct rcu_state *rsp; }; /* Values for nocb_defer_wakeup field in struct rcu_data. */ diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index b60d3df92ff5..5423f9e58494 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -350,7 +350,7 @@ void rcu_note_context_switch(bool preempt) */ WARN_ON_ONCE((rdp->grpmask & rcu_rnp_online_cpus(rnp)) == 0); WARN_ON_ONCE(!list_empty(&t->rcu_node_entry)); - trace_rcu_preempt_task(rdp->rsp->name, + trace_rcu_preempt_task(rcu_state.name, t->pid, (rnp->qsmask & rdp->grpmask) ? rnp->gp_seq @@ -1951,7 +1951,7 @@ static void wake_nocb_leader_defer(struct rcu_data *rdp, int waketype, if (rdp->nocb_defer_wakeup == RCU_NOCB_WAKE_NOT) mod_timer(&rdp->nocb_timer, jiffies + 1); WRITE_ONCE(rdp->nocb_defer_wakeup, waketype); - trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, reason); + trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, reason); raw_spin_unlock_irqrestore(&rdp->nocb_lock, flags); } @@ -2030,7 +2030,7 @@ static void __call_rcu_nocb_enqueue(struct rcu_data *rdp, /* If we are not being polled and there is a kthread, awaken it ... */ t = READ_ONCE(rdp->nocb_kthread); if (rcu_nocb_poll || !t) { - trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, + trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("WakeNotPoll")); return; } @@ -2039,7 +2039,7 @@ static void __call_rcu_nocb_enqueue(struct rcu_data *rdp, if (!irqs_disabled_flags(flags)) { /* ... if queue was empty ... */ wake_nocb_leader(rdp, false); - trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, + trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("WakeEmpty")); } else { wake_nocb_leader_defer(rdp, RCU_NOCB_WAKE, @@ -2050,7 +2050,7 @@ static void __call_rcu_nocb_enqueue(struct rcu_data *rdp, /* ... or if many callbacks queued. */ if (!irqs_disabled_flags(flags)) { wake_nocb_leader(rdp, true); - trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, + trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("WakeOvf")); } else { wake_nocb_leader_defer(rdp, RCU_NOCB_WAKE_FORCE, @@ -2058,7 +2058,7 @@ static void __call_rcu_nocb_enqueue(struct rcu_data *rdp, } rdp->qlen_last_fqs_check = LONG_MAX / 2; } else { - trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("WakeNot")); + trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("WakeNot")); } return; } @@ -2080,12 +2080,12 @@ static bool __call_rcu_nocb(struct rcu_data *rdp, struct rcu_head *rhp, return false; __call_rcu_nocb_enqueue(rdp, rhp, &rhp->next, 1, lazy, flags); if (__is_kfree_rcu_offset((unsigned long)rhp->func)) - trace_rcu_kfree_callback(rdp->rsp->name, rhp, + trace_rcu_kfree_callback(rcu_state.name, rhp, (unsigned long)rhp->func, -atomic_long_read(&rdp->nocb_q_count_lazy), -atomic_long_read(&rdp->nocb_q_count)); else - trace_rcu_callback(rdp->rsp->name, rhp, + trace_rcu_callback(rcu_state.name, rhp, -atomic_long_read(&rdp->nocb_q_count_lazy), -atomic_long_read(&rdp->nocb_q_count)); @@ -2135,7 +2135,7 @@ static void rcu_nocb_wait_gp(struct rcu_data *rdp) struct rcu_node *rnp = rdp->mynode; local_irq_save(flags); - c = rcu_seq_snap(&rdp->rsp->gp_seq); + c = rcu_seq_snap(&rcu_state.gp_seq); if (!rdp->gpwrap && ULONG_CMP_GE(rdp->gp_seq_needed, c)) { local_irq_restore(flags); } else { @@ -2180,7 +2180,7 @@ wait_again: /* Wait for callbacks to appear. */ if (!rcu_nocb_poll) { - trace_rcu_nocb_wake(my_rdp->rsp->name, my_rdp->cpu, TPS("Sleep")); + trace_rcu_nocb_wake(rcu_state.name, my_rdp->cpu, TPS("Sleep")); swait_event_interruptible_exclusive(my_rdp->nocb_wq, !READ_ONCE(my_rdp->nocb_leader_sleep)); raw_spin_lock_irqsave(&my_rdp->nocb_lock, flags); @@ -2190,7 +2190,7 @@ wait_again: raw_spin_unlock_irqrestore(&my_rdp->nocb_lock, flags); } else if (firsttime) { firsttime = false; /* Don't drown trace log with "Poll"! */ - trace_rcu_nocb_wake(my_rdp->rsp->name, my_rdp->cpu, TPS("Poll")); + trace_rcu_nocb_wake(rcu_state.name, my_rdp->cpu, TPS("Poll")); } /* @@ -2217,7 +2217,7 @@ wait_again: if (rcu_nocb_poll) { schedule_timeout_interruptible(1); } else { - trace_rcu_nocb_wake(my_rdp->rsp->name, my_rdp->cpu, + trace_rcu_nocb_wake(rcu_state.name, my_rdp->cpu, TPS("WokeEmpty")); } goto wait_again; @@ -2262,7 +2262,7 @@ wait_again: static void nocb_follower_wait(struct rcu_data *rdp) { for (;;) { - trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("FollowerSleep")); + trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("FollowerSleep")); swait_event_interruptible_exclusive(rdp->nocb_wq, READ_ONCE(rdp->nocb_follower_head)); if (smp_load_acquire(&rdp->nocb_follower_head)) { @@ -2270,7 +2270,7 @@ static void nocb_follower_wait(struct rcu_data *rdp) return; } WARN_ON(signal_pending(current)); - trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("WokeEmpty")); + trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("WokeEmpty")); } } @@ -2305,10 +2305,10 @@ static int rcu_nocb_kthread(void *arg) rdp->nocb_follower_tail = &rdp->nocb_follower_head; raw_spin_unlock_irqrestore(&rdp->nocb_lock, flags); BUG_ON(!list); - trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("WokeNonEmpty")); + trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("WokeNonEmpty")); /* Each pass through the following loop invokes a callback. */ - trace_rcu_batch_start(rdp->rsp->name, + trace_rcu_batch_start(rcu_state.name, atomic_long_read(&rdp->nocb_q_count_lazy), atomic_long_read(&rdp->nocb_q_count), -1); c = cl = 0; @@ -2316,23 +2316,23 @@ static int rcu_nocb_kthread(void *arg) next = list->next; /* Wait for enqueuing to complete, if needed. */ while (next == NULL && &list->next != tail) { - trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, + trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("WaitQueue")); schedule_timeout_interruptible(1); - trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, + trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("WokeQueue")); next = list->next; } debug_rcu_head_unqueue(list); local_bh_disable(); - if (__rcu_reclaim(rdp->rsp->name, list)) + if (__rcu_reclaim(rcu_state.name, list)) cl++; c++; local_bh_enable(); cond_resched_tasks_rcu_qs(); list = next; } - trace_rcu_batch_end(rdp->rsp->name, c, !!list, 0, 0, 1); + trace_rcu_batch_end(rcu_state.name, c, !!list, 0, 0, 1); smp_mb__before_atomic(); /* _add after CB invocation. */ atomic_long_add(-c, &rdp->nocb_q_count); atomic_long_add(-cl, &rdp->nocb_q_count_lazy); @@ -2360,7 +2360,7 @@ static void do_nocb_deferred_wakeup_common(struct rcu_data *rdp) ndw = READ_ONCE(rdp->nocb_defer_wakeup); WRITE_ONCE(rdp->nocb_defer_wakeup, RCU_NOCB_WAKE_NOT); __wake_nocb_leader(rdp, ndw == RCU_NOCB_WAKE_FORCE, flags); - trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("DeferredWake")); + trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("DeferredWake")); } /* Do a deferred wakeup of rcu_nocb_kthread() from a timer handler. */