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docs/RCU/rcubarrier: Right-adjust line numbers in code snippets
Line numbers in code snippets in rcubarrier.rst have beed left adjusted since commit 4af4983 ("doc: Convert to rcubarrier.txt to ReST"). This might have been because right adjusting them had confused Sphinx. The rules around a literal block in reST are: - Need a blank line above it. - A line with the same indent level as the line above it is regarded as the end of it. Those line numbers can be right adjusted by keeping indents at two- digit numbers. While at it, add some spaces between the column of line numbers and the code area for better readability. Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
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‎Documentation/RCU/rcubarrier.rst‎

Lines changed: 84 additions & 84 deletions
Original file line numberDiff line numberDiff line change
@@ -72,79 +72,79 @@ For example, if it uses call_rcu(), call_srcu() on srcu_struct_1, and
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call_srcu() on srcu_struct_2, then the following three lines of code
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will be required when unloading::
7474

75-
1 rcu_barrier();
76-
2 srcu_barrier(&srcu_struct_1);
77-
3 srcu_barrier(&srcu_struct_2);
75+
1 rcu_barrier();
76+
2 srcu_barrier(&srcu_struct_1);
77+
3 srcu_barrier(&srcu_struct_2);
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7979
If latency is of the essence, workqueues could be used to run these
8080
three functions concurrently.
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8282
An ancient version of the rcutorture module makes use of rcu_barrier()
8383
in its exit function as follows::
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85-
1 static void
86-
2 rcu_torture_cleanup(void)
87-
3 {
88-
4 int i;
89-
5
90-
6 fullstop = 1;
91-
7 if (shuffler_task != NULL) {
92-
8 VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task");
93-
9 kthread_stop(shuffler_task);
94-
10 }
95-
11 shuffler_task = NULL;
85+
1 static void
86+
2 rcu_torture_cleanup(void)
87+
3 {
88+
4 int i;
89+
5
90+
6 fullstop = 1;
91+
7 if (shuffler_task != NULL) {
92+
8 VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task");
93+
9 kthread_stop(shuffler_task);
94+
10 }
95+
11 shuffler_task = NULL;
9696
12
97-
13 if (writer_task != NULL) {
98-
14 VERBOSE_PRINTK_STRING("Stopping rcu_torture_writer task");
99-
15 kthread_stop(writer_task);
100-
16 }
101-
17 writer_task = NULL;
97+
13 if (writer_task != NULL) {
98+
14 VERBOSE_PRINTK_STRING("Stopping rcu_torture_writer task");
99+
15 kthread_stop(writer_task);
100+
16 }
101+
17 writer_task = NULL;
102102
18
103-
19 if (reader_tasks != NULL) {
104-
20 for (i = 0; i < nrealreaders; i++) {
105-
21 if (reader_tasks[i] != NULL) {
106-
22 VERBOSE_PRINTK_STRING(
107-
23 "Stopping rcu_torture_reader task");
108-
24 kthread_stop(reader_tasks[i]);
109-
25 }
110-
26 reader_tasks[i] = NULL;
111-
27 }
112-
28 kfree(reader_tasks);
113-
29 reader_tasks = NULL;
114-
30 }
115-
31 rcu_torture_current = NULL;
103+
19 if (reader_tasks != NULL) {
104+
20 for (i = 0; i < nrealreaders; i++) {
105+
21 if (reader_tasks[i] != NULL) {
106+
22 VERBOSE_PRINTK_STRING(
107+
23 "Stopping rcu_torture_reader task");
108+
24 kthread_stop(reader_tasks[i]);
109+
25 }
110+
26 reader_tasks[i] = NULL;
111+
27 }
112+
28 kfree(reader_tasks);
113+
29 reader_tasks = NULL;
114+
30 }
115+
31 rcu_torture_current = NULL;
116116
32
117-
33 if (fakewriter_tasks != NULL) {
118-
34 for (i = 0; i < nfakewriters; i++) {
119-
35 if (fakewriter_tasks[i] != NULL) {
120-
36 VERBOSE_PRINTK_STRING(
121-
37 "Stopping rcu_torture_fakewriter task");
122-
38 kthread_stop(fakewriter_tasks[i]);
123-
39 }
124-
40 fakewriter_tasks[i] = NULL;
125-
41 }
126-
42 kfree(fakewriter_tasks);
127-
43 fakewriter_tasks = NULL;
128-
44 }
117+
33 if (fakewriter_tasks != NULL) {
118+
34 for (i = 0; i < nfakewriters; i++) {
119+
35 if (fakewriter_tasks[i] != NULL) {
120+
36 VERBOSE_PRINTK_STRING(
121+
37 "Stopping rcu_torture_fakewriter task");
122+
38 kthread_stop(fakewriter_tasks[i]);
123+
39 }
124+
40 fakewriter_tasks[i] = NULL;
125+
41 }
126+
42 kfree(fakewriter_tasks);
127+
43 fakewriter_tasks = NULL;
128+
44 }
129129
45
130-
46 if (stats_task != NULL) {
131-
47 VERBOSE_PRINTK_STRING("Stopping rcu_torture_stats task");
132-
48 kthread_stop(stats_task);
133-
49 }
134-
50 stats_task = NULL;
130+
46 if (stats_task != NULL) {
131+
47 VERBOSE_PRINTK_STRING("Stopping rcu_torture_stats task");
132+
48 kthread_stop(stats_task);
133+
49 }
134+
50 stats_task = NULL;
135135
51
136-
52 /* Wait for all RCU callbacks to fire. */
137-
53 rcu_barrier();
136+
52 /* Wait for all RCU callbacks to fire. */
137+
53 rcu_barrier();
138138
54
139-
55 rcu_torture_stats_print(); /* -After- the stats thread is stopped! */
139+
55 rcu_torture_stats_print(); /* -After- the stats thread is stopped! */
140140
56
141-
57 if (cur_ops->cleanup != NULL)
142-
58 cur_ops->cleanup();
143-
59 if (atomic_read(&n_rcu_torture_error))
144-
60 rcu_torture_print_module_parms("End of test: FAILURE");
145-
61 else
146-
62 rcu_torture_print_module_parms("End of test: SUCCESS");
147-
63 }
141+
57 if (cur_ops->cleanup != NULL)
142+
58 cur_ops->cleanup();
143+
59 if (atomic_read(&n_rcu_torture_error))
144+
60 rcu_torture_print_module_parms("End of test: FAILURE");
145+
61 else
146+
62 rcu_torture_print_module_parms("End of test: SUCCESS");
147+
63 }
148148

149149
Line 6 sets a global variable that prevents any RCU callbacks from
150150
re-posting themselves. This will not be necessary in most cases, since
@@ -193,16 +193,16 @@ which point, all earlier RCU callbacks are guaranteed to have completed.
193193

194194
The original code for rcu_barrier() was roughly as follows::
195195

196-
1 void rcu_barrier(void)
197-
2 {
198-
3 BUG_ON(in_interrupt());
199-
4 /* Take cpucontrol mutex to protect against CPU hotplug */
200-
5 mutex_lock(&rcu_barrier_mutex);
201-
6 init_completion(&rcu_barrier_completion);
202-
7 atomic_set(&rcu_barrier_cpu_count, 1);
203-
8 on_each_cpu(rcu_barrier_func, NULL, 0, 1);
204-
9 if (atomic_dec_and_test(&rcu_barrier_cpu_count))
205-
10 complete(&rcu_barrier_completion);
196+
1 void rcu_barrier(void)
197+
2 {
198+
3 BUG_ON(in_interrupt());
199+
4 /* Take cpucontrol mutex to protect against CPU hotplug */
200+
5 mutex_lock(&rcu_barrier_mutex);
201+
6 init_completion(&rcu_barrier_completion);
202+
7 atomic_set(&rcu_barrier_cpu_count, 1);
203+
8 on_each_cpu(rcu_barrier_func, NULL, 0, 1);
204+
9 if (atomic_dec_and_test(&rcu_barrier_cpu_count))
205+
10 complete(&rcu_barrier_completion);
206206
11 wait_for_completion(&rcu_barrier_completion);
207207
12 mutex_unlock(&rcu_barrier_mutex);
208208
13 }
@@ -232,16 +232,16 @@ still gives the general idea.
232232
The rcu_barrier_func() runs on each CPU, where it invokes call_rcu()
233233
to post an RCU callback, as follows::
234234

235-
1 static void rcu_barrier_func(void *notused)
236-
2 {
237-
3 int cpu = smp_processor_id();
238-
4 struct rcu_data *rdp = &per_cpu(rcu_data, cpu);
239-
5 struct rcu_head *head;
240-
6
241-
7 head = &rdp->barrier;
242-
8 atomic_inc(&rcu_barrier_cpu_count);
243-
9 call_rcu(head, rcu_barrier_callback);
244-
10 }
235+
1 static void rcu_barrier_func(void *notused)
236+
2 {
237+
3 int cpu = smp_processor_id();
238+
4 struct rcu_data *rdp = &per_cpu(rcu_data, cpu);
239+
5 struct rcu_head *head;
240+
6
241+
7 head = &rdp->barrier;
242+
8 atomic_inc(&rcu_barrier_cpu_count);
243+
9 call_rcu(head, rcu_barrier_callback);
244+
10 }
245245

246246
Lines 3 and 4 locate RCU's internal per-CPU rcu_data structure,
247247
which contains the struct rcu_head that needed for the later call to
@@ -254,11 +254,11 @@ The rcu_barrier_callback() function simply atomically decrements the
254254
rcu_barrier_cpu_count variable and finalizes the completion when it
255255
reaches zero, as follows::
256256

257-
1 static void rcu_barrier_callback(struct rcu_head *notused)
258-
2 {
259-
3 if (atomic_dec_and_test(&rcu_barrier_cpu_count))
260-
4 complete(&rcu_barrier_completion);
261-
5 }
257+
1 static void rcu_barrier_callback(struct rcu_head *notused)
258+
2 {
259+
3 if (atomic_dec_and_test(&rcu_barrier_cpu_count))
260+
4 complete(&rcu_barrier_completion);
261+
5 }
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263263
.. _rcubarrier_quiz_3:
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