Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To:     linux-kernel@vger.kernel.org
Cc:     mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com,
        akpm@linux-foundation.org, mathieu.desnoyers@efficios.com,
        josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org,
        rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com,
        fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Subject: [PATCH tip/core/rcu 35/52] rcu: Remove rsp parameter from dump_blkd_tasks() and friend
Date:   Wed, 29 Aug 2018 15:38:37 -0700
In-Reply-To: <20180829223830.GA1800@linux.vnet.ibm.com>
References: <20180829223830.GA1800@linux.vnet.ibm.com>
Message-Id: <20180829223854.4055-35-paulmck@linux.vnet.ibm.com>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

There now is only one rcu_state structure in a given build of the
Linux kernel, so there is no need to pass it as a parameter to RCU's
functions.  This commit therefore removes the rsp parameter from
dump_blkd_tasks() and rcu_preempt_blocked_readers_cgp().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---
 kernel/rcu/tree.c        |  4 ++--
 kernel/rcu/tree.h        |  6 ++----
 kernel/rcu/tree_plugin.h | 12 +++++-------
 3 files changed, 9 insertions(+), 13 deletions(-)

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index e484ee95a192..aa81958edec8 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -1936,7 +1936,7 @@ static bool rcu_gp_init(void)
 		rcu_gp_slow(gp_init_delay);
 		raw_spin_lock_irqsave_rcu_node(rnp, flags);
 		rdp = this_cpu_ptr(&rcu_data);
-		rcu_preempt_check_blocked_tasks(rsp, rnp);
+		rcu_preempt_check_blocked_tasks(rnp);
 		rnp->qsmask = rnp->qsmaskinit;
 		WRITE_ONCE(rnp->gp_seq, rsp->gp_seq);
 		if (rnp == rdp->mynode)
@@ -2048,7 +2048,7 @@ static void rcu_gp_cleanup(void)
 	rcu_for_each_node_breadth_first(rsp, rnp) {
 		raw_spin_lock_irq_rcu_node(rnp);
 		if (WARN_ON_ONCE(rcu_preempt_blocked_readers_cgp(rnp)))
-			dump_blkd_tasks(rsp, rnp, 10);
+			dump_blkd_tasks(rnp, 10);
 		WARN_ON_ONCE(rnp->qsmask);
 		WRITE_ONCE(rnp->gp_seq, new_gp_seq);
 		rdp = this_cpu_ptr(&rcu_data);
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
index 00d268cb4d04..ccdee6bd3919 100644
--- a/kernel/rcu/tree.h
+++ b/kernel/rcu/tree.h
@@ -455,12 +455,10 @@ static bool rcu_preempt_has_tasks(struct rcu_node *rnp);
 static void rcu_print_detail_task_stall(void);
 static int rcu_print_task_stall(struct rcu_node *rnp);
 static int rcu_print_task_exp_stall(struct rcu_node *rnp);
-static void rcu_preempt_check_blocked_tasks(struct rcu_state *rsp,
-					    struct rcu_node *rnp);
+static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp);
 static void rcu_flavor_check_callbacks(int user);
 void call_rcu(struct rcu_head *head, rcu_callback_t func);
-static void dump_blkd_tasks(struct rcu_state *rsp, struct rcu_node *rnp,
-			    int ncheck);
+static void dump_blkd_tasks(struct rcu_node *rnp, int ncheck);
 static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags);
 static void rcu_preempt_boost_start_gp(struct rcu_node *rnp);
 static void invoke_rcu_callbacks_kthread(void);
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 1d8148b0d4e5..9a3d30121815 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -756,14 +756,13 @@ static int rcu_print_task_exp_stall(struct rcu_node *rnp)
  * Also, if there are blocked tasks on the list, they automatically
  * block the newly created grace period, so set up ->gp_tasks accordingly.
  */
-static void
-rcu_preempt_check_blocked_tasks(struct rcu_state *rsp, struct rcu_node *rnp)
+static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp)
 {
 	struct task_struct *t;
 
 	RCU_LOCKDEP_WARN(preemptible(), "rcu_preempt_check_blocked_tasks() invoked with preemption enabled!!!\n");
 	if (WARN_ON_ONCE(rcu_preempt_blocked_readers_cgp(rnp)))
-		dump_blkd_tasks(rsp, rnp, 10);
+		dump_blkd_tasks(rnp, 10);
 	if (rcu_preempt_has_tasks(rnp) &&
 	    (rnp->qsmaskinit || rnp->wait_blkd_tasks)) {
 		rnp->gp_tasks = rnp->blkd_tasks.next;
@@ -884,7 +883,7 @@ void exit_rcu(void)
  * specified number of elements.
  */
 static void
-dump_blkd_tasks(struct rcu_state *rsp, struct rcu_node *rnp, int ncheck)
+dump_blkd_tasks(struct rcu_node *rnp, int ncheck)
 {
 	int cpu;
 	int i;
@@ -1033,8 +1032,7 @@ static int rcu_print_task_exp_stall(struct rcu_node *rnp)
  * so there is no need to check for blocked tasks.  So check only for
  * bogus qsmask values.
  */
-static void
-rcu_preempt_check_blocked_tasks(struct rcu_state *rsp, struct rcu_node *rnp)
+static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp)
 {
 	WARN_ON_ONCE(rnp->qsmask);
 }
@@ -1095,7 +1093,7 @@ void exit_rcu(void)
  * Dump the guaranteed-empty blocked-tasks state.  Trust but verify.
  */
 static void
-dump_blkd_tasks(struct rcu_state *rsp, struct rcu_node *rnp, int ncheck)
+dump_blkd_tasks(struct rcu_node *rnp, int ncheck)
 {
 	WARN_ON_ONCE(!list_empty(&rnp->blkd_tasks));
 }
-- 
2.17.1