From: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Date: Thu, 30 Aug 2018 23:12:53 +0000 (-0700)
Subject: Merge branches 'doc.2018.08.30a', 'dynticks.2018.08.30b', 'srcu.2018.08.30b' and... 
X-Git-Tag: v4.20-rc1~172^2^2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b56ada120921fbb0a4fb2a5bee163717182e7e9e;p=thirdparty%2Flinux.git

Merge branches 'doc.2018.08.30a', 'dynticks.2018.08.30b', 'srcu.2018.08.30b' and 'torture.2018.08.29a' into HEAD

doc.2018.08.30a: Documentation updates
dynticks.2018.08.30b: RCU flavor consolidation updates and cleanups
srcu.2018.08.30b: SRCU updates
torture.2018.08.29a: Torture-test updates
---

b56ada120921fbb0a4fb2a5bee163717182e7e9e
diff --cc Documentation/RCU/Design/Requirements/Requirements.html
index 701b5c53607f8,038714475edbf,49690228b1c69,49690228b1c69..43c4e2f05f402
--- a/Documentation/RCU/Design/Requirements/Requirements.html
+++ b/Documentation/RCU/Design/Requirements/Requirements.html
@@@@@ -2929,20 -2916,8 -2918,8 -2918,8 +2927,20 @@@@@ include
    <tt>call_rcu_bh()</tt>,
    <tt>rcu_barrier_bh()</tt>, and
    <tt>rcu_read_lock_bh_held()</tt>.
 +++However, the update-side APIs are now simple wrappers for other RCU
 +++flavors, namely RCU-sched in CONFIG_PREEMPT=n kernels and RCU-preempt
 +++otherwise.
  ++
 -  <h3><a name="Sched Flavor">Sched Flavor</a></h3>
 +++<h3><a name="Sched Flavor">Sched Flavor (Historical)</a></h3>
 +  
  --<h3><a name="Sched Flavor">Sched Flavor</a></h3>
 +++<p>
 +++The RCU-sched flavor of RCU has since been expressed in terms of
 +++the other RCU flavors as part of a consolidation of the three
 +++flavors into a single flavor.
 +++The read-side API remains, and continues to disable preemption and to
 +++be accounted for by lockdep.
 +++Much of the material in this section is therefore strictly historical
 +++in nature.
    
    <p>
    Before preemptible RCU, waiting for an RCU grace period had the
diff --cc kernel/rcu/rcutorture.c
index c596c6f1e4571,1141e0d84ff12,c596c6f1e4571,a02a2f21386ba..210c774603656
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@@@@ -325,7 -343,8 -325,7 -333,9 +351,10 @@@@@ rcu_read_delay(struct torture_random_st
    	if (!(torture_random(rrsp) % (nrealreaders * 2000 * longdelay_ms))) {
    		started = cur_ops->get_gp_seq();
    		ts = rcu_trace_clock_local();
+++ 		if (preempt_count() & (SOFTIRQ_MASK | HARDIRQ_MASK))
+++ 			longdelay_ms = 5; /* Avoid triggering BH limits. */
    		mdelay(longdelay_ms);
+ ++		rtrsp->rt_delay_ms = longdelay_ms;
    		completed = cur_ops->get_gp_seq();
    		do_trace_rcu_torture_read(cur_ops->name, NULL, ts,
    					  started, completed);
@@@@@ -429,8 -452,9 -429,8 -439,9 +462,10 @@@@@ static struct rcu_torture_ops rcu_ops 
    	.cb_barrier	= rcu_barrier,
    	.fqs		= rcu_force_quiescent_state,
    	.stats		= NULL,
+++ 	.stall_dur	= rcu_jiffies_till_stall_check,
    	.irq_capable	= 1,
    	.can_boost	= rcu_can_boost(),
+ ++	.extendables	= RCUTORTURE_MAX_EXTEND,
    	.name		= "rcu"
    };
    
diff --cc kernel/rcu/update.c
index 39cb23d221093,fa089ead4bd6a,7d057d0aaec40,a6b860422d184..f203b94f6b5be
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@@@@ -891,24 -882,10 -893,27 -892,24 +885,13 @@@@@ DEFINE_STATIC_SRCU(early_srcu)
    static void early_boot_test_call_rcu(void)
    {
    	static struct rcu_head head;
++ +	static struct rcu_head shead;
    
    	call_rcu(&head, test_callback);
-  -}
-  -
-  -static void early_boot_test_call_rcu_bh(void)
-  -{
-  -	static struct rcu_head head;
-  -
-  -	call_rcu_bh(&head, test_callback);
-  -}
-  -
-  -static void early_boot_test_call_rcu_sched(void)
-  -{
-  -	static struct rcu_head head;
-  -
-  -	call_rcu_sched(&head, test_callback);
++ +	if (IS_ENABLED(CONFIG_SRCU))
++ +		call_srcu(&early_srcu, &shead, test_callback);
    }
    
  - static void early_boot_test_call_rcu_bh(void)
  - {
  - 	static struct rcu_head head;
  - 
  - 	call_rcu_bh(&head, test_callback);
  - }
  - 
  - static void early_boot_test_call_rcu_sched(void)
  - {
  - 	static struct rcu_head head;
  - 
  - 	call_rcu_sched(&head, test_callback);
  - }
  - 
    void rcu_early_boot_tests(void)
    {
    	pr_info("Running RCU self tests\n");
@@@@@ -930,16 -903,7 -935,20 -931,16 +909,11 @@@@@ static int rcu_verify_early_boot_tests(
    	if (rcu_self_test) {
    		early_boot_test_counter++;
    		rcu_barrier();
++ +		if (IS_ENABLED(CONFIG_SRCU)) {
++ +			early_boot_test_counter++;
++ +			srcu_barrier(&early_srcu);
++ +		}
    	}
- --	if (rcu_self_test_bh) {
- --		early_boot_test_counter++;
- --		rcu_barrier_bh();
- --	}
- --	if (rcu_self_test_sched) {
- --		early_boot_test_counter++;
- --		rcu_barrier_sched();
- --	}
- --
    	if (rcu_self_test_counter != early_boot_test_counter) {
    		WARN_ON(1);
    		ret = -1;