smp_call_function_interrupt: use typedef and %pf

Use the newly added smp_call_func_t in smp_call_function_interrupt for the func variable, and make the comment above the WARN more assertive and explicit. Also, func is a function pointer and does not need an offset, so use %pf not %pS. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

smp_call_function_interrupt: use typedef and %pf
Use the newly added smp_call_func_t in smp_call_function_interrupt for the func variable, and make the comment above the WARN more assertive and explicit. Also, func is a function pointer and does not need an offset, so use %pf not %pS. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Milton Miller · Linus Torvalds
1 parent 723aae25d5
Showing 1 changed file with 8 additions and 8 deletions Side-by-side Diff
kernel/smp.c
@@ -194,7 +194,7 @@
 	 */
 	list_for_each_entry_rcu(data, &call_function.queue, csd.list) {
 		int refs;
-		void (*func) (void *info);
+		smp_call_func_t func;
  
 		/*
 		 * Since we walk the list without any locks, we might
  
  
@@ -214,17 +214,17 @@
 		if (atomic_read(&data->refs) == 0)
 			continue;
  
-		func = data->csd.func;			/* for later warn */
-		data->csd.func(data->csd.info);
+		func = data->csd.func;		/* save for later warn */
+		func(data->csd.info);
  
 		/*
-		 * If the cpu mask is not still set then it enabled interrupts,
-		 * we took another smp interrupt, and executed the function
-		 * twice on this cpu.  In theory that copy decremented refs.
+		 * If the cpu mask is not still set then func enabled
+		 * interrupts (BUG), and this cpu took another smp call
+		 * function interrupt and executed func(info) twice
+		 * on this cpu.  That nested execution decremented refs.
 		 */
 		if (!cpumask_test_and_clear_cpu(cpu, data->cpumask)) {
-			WARN(1, "%pS enabled interrupts and double executed\n",
-			     func);
+			WARN(1, "%pf enabled interrupts and double executed\n", func);
 			continue;
 		}
...	...	@@ -194,7 +194,7 @@
194	194	*/
195	195	list_for_each_entry_rcu(data, &call_function.queue, csd.list) {
196	196	int refs;
197		- void (func) (void info);
	197	+ smp_call_func_t func;
198	198
199	199	/*
200	200	* Since we walk the list without any locks, we might
201	201
202	202
...	...	@@ -214,17 +214,17 @@
214	214	if (atomic_read(&data->refs) == 0)
215	215	continue;
216	216
217		- func = data->csd.func; /* for later warn */
218		- data->csd.func(data->csd.info);
	217	+ func = data->csd.func; /* save for later warn */
	218	+ func(data->csd.info);
219	219
220	220	/*
221		- * If the cpu mask is not still set then it enabled interrupts,
222		- * we took another smp interrupt, and executed the function
223		- * twice on this cpu. In theory that copy decremented refs.
	221	+ * If the cpu mask is not still set then func enabled
	222	+ * interrupts (BUG), and this cpu took another smp call
	223	+ * function interrupt and executed func(info) twice
	224	+ * on this cpu. That nested execution decremented refs.
224	225	*/
225	226	if (!cpumask_test_and_clear_cpu(cpu, data->cpumask)) {
226		- WARN(1, "%pS enabled interrupts and double executed\n",
227		- func);
	227	+ WARN(1, "%pf enabled interrupts and double executed\n", func);
228	228	continue;
229	229	}
230	230