rcu: Create an immutable rcu_data_p pointer to default rcu_data structure (2927a689) · Commits · 戴 / test

kernel/rcu/tree.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -111,6 +111,7 @@ RCU_STATE_INITIALIZER(rcu_sched, 's', call_rcu_sched);
		RCU_STATE_INITIALIZER(rcu_bh, 'b', call_rcu_bh);

		static struct rcu_state *const rcu_state_p;
		static struct rcu_data __percpu *const rcu_data_p;
		LIST_HEAD(rcu_struct_flavors);

		/* Increase (but not decrease) the CONFIG_RCU_FANOUT_LEAF at boot time. */

kernel/rcu/tree_plugin.h

+9 −7

Original line number	Diff line number	Diff line
		@@ -101,6 +101,7 @@ static void __init rcu_bootup_announce_oddness(void)

		RCU_STATE_INITIALIZER(rcu_preempt, 'p', call_rcu);
		static struct rcu_state *const rcu_state_p = &rcu_preempt_state;
		static struct rcu_data __percpu *const rcu_data_p = &rcu_preempt_data;

		static int rcu_preempted_readers_exp(struct rcu_node *rnp);
		static void rcu_report_exp_rnp(struct rcu_state rsp, struct rcu_node rnp,
		@@ -126,11 +127,11 @@ static void __init rcu_bootup_announce(void)
		*/
		static void rcu_preempt_qs(void)
		{
		if (!__this_cpu_read(rcu_preempt_data.passed_quiesce)) {
		if (!__this_cpu_read(rcu_data_p->passed_quiesce)) {
		trace_rcu_grace_period(TPS("rcu_preempt"),
		__this_cpu_read(rcu_preempt_data.gpnum),
		__this_cpu_read(rcu_data_p->gpnum),
		TPS("cpuqs"));
		__this_cpu_write(rcu_preempt_data.passed_quiesce, 1);
		__this_cpu_write(rcu_data_p->passed_quiesce, 1);
		barrier(); /* Coordinate with rcu_preempt_check_callbacks(). */
		current->rcu_read_unlock_special.b.need_qs = false;
		}
		@@ -495,8 +496,8 @@ static void rcu_preempt_check_callbacks(void)
		return;
		}
		if (t->rcu_read_lock_nesting > 0 &&
		__this_cpu_read(rcu_preempt_data.qs_pending) &&
		!__this_cpu_read(rcu_preempt_data.passed_quiesce))
		__this_cpu_read(rcu_data_p->qs_pending) &&
		!__this_cpu_read(rcu_data_p->passed_quiesce))
		t->rcu_read_unlock_special.b.need_qs = true;
		}

		@@ -504,7 +505,7 @@ static void rcu_preempt_check_callbacks(void)

		static void rcu_preempt_do_callbacks(void)
		{
		rcu_do_batch(rcu_state_p, this_cpu_ptr(&rcu_preempt_data));
		rcu_do_batch(rcu_state_p, this_cpu_ptr(rcu_data_p));
		}

		#endif /* #ifdef CONFIG_RCU_BOOST */
		@@ -811,7 +812,7 @@ EXPORT_SYMBOL_GPL(rcu_barrier);
		*/
		static void __init __rcu_init_preempt(void)
		{
		rcu_init_one(rcu_state_p, &rcu_preempt_data);
		rcu_init_one(rcu_state_p, rcu_data_p);
		}

		/*
		@@ -835,6 +836,7 @@ void exit_rcu(void)
		#else /* #ifdef CONFIG_PREEMPT_RCU */

		static struct rcu_state *const rcu_state_p = &rcu_sched_state;
		static struct rcu_data __percpu *const rcu_data_p = &rcu_sched_data;

		/*
		* Tell them what RCU they are running.

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