Reduce splat_taskq_test2_impl() stack frame size

Slightly increasing the size of a kmutex_t has caused us to exceed
the stack frame warning size in splat_taskq_test2_impl().  To address
this the tq_args have been moved to the heap.

  cc1: warnings being treated as errors
  spl-0.6.3/module/splat/splat-taskq.c:358:
  error: the frame size of 1040 bytes is larger than 1024 bytes

Signed-off-by: Brian Behlendorf <[email protected]>
Signed-off-by: Tim Chase <[email protected]>
Issue #435

1 files changed, 31 insertions, 20 deletions

diff --git a/module/splat/splat-taskq.c b/module/splat/splat-taskq.c
index 8229fed39..2787bf401 100644
--- a/module/splat/splat-taskq.c
+++ b/module/splat/splat-taskq.c
@@ -231,7 +231,7 @@ static int
 splat_taskq_test2_impl(struct file *file, void *arg, boolean_t prealloc) {
 	taskq_t *tq[TEST2_TASKQS] = { NULL };
 	taskqid_t id;
-	splat_taskq_arg_t tq_args[TEST2_TASKQS];
+	splat_taskq_arg_t *tq_args[TEST2_TASKQS] = { NULL };
 	taskq_ent_t *func1_tqes = NULL;
 	taskq_ent_t *func2_tqes = NULL;
 	int i, rc = 0;
@@ -252,6 +252,12 @@ splat_taskq_test2_impl(struct file *file, void *arg, boolean_t prealloc) {
 		taskq_init_ent(&func1_tqes[i]);
 		taskq_init_ent(&func2_tqes[i]);
 
+		tq_args[i] = kmalloc(sizeof (splat_taskq_arg_t), GFP_KERNEL);
+		if (tq_args[i] == NULL) {
+			rc = -ENOMEM;
+			break;
+		}
+
 		splat_vprint(file, SPLAT_TASKQ_TEST2_NAME,
 			     "Taskq '%s/%d' creating (%s dispatch)\n",
 			     SPLAT_TASKQ_TEST2_NAME, i,
@@ -267,28 +273,28 @@ splat_taskq_test2_impl(struct file *file, void *arg, boolean_t prealloc) {
 			break;
 		}
 
-		tq_args[i].flag = i;
-		tq_args[i].id   = i;
-		tq_args[i].file = file;
-		tq_args[i].name = SPLAT_TASKQ_TEST2_NAME;
+		tq_args[i]->flag = i;
+		tq_args[i]->id   = i;
+		tq_args[i]->file = file;
+		tq_args[i]->name = SPLAT_TASKQ_TEST2_NAME;
 
 		splat_vprint(file, SPLAT_TASKQ_TEST2_NAME,
 		           "Taskq '%s/%d' function '%s' dispatching\n",
-			   tq_args[i].name, tq_args[i].id,
+			   tq_args[i]->name, tq_args[i]->id,
 		           sym2str(splat_taskq_test2_func1));
 		if (prealloc) {
 			taskq_dispatch_ent(tq[i], splat_taskq_test2_func1,
-			                 &tq_args[i], TQ_SLEEP, &func1_tqes[i]);
+			    tq_args[i], TQ_SLEEP, &func1_tqes[i]);
 			id = func1_tqes[i].tqent_id;
 		} else {
 			id = taskq_dispatch(tq[i], splat_taskq_test2_func1,
-					    &tq_args[i], TQ_SLEEP);
+			    tq_args[i], TQ_SLEEP);
 		}
 
 		if (id == 0) {
 			splat_vprint(file, SPLAT_TASKQ_TEST2_NAME,
 			           "Taskq '%s/%d' function '%s' dispatch "
-			           "failed\n", tq_args[i].name, tq_args[i].id,
+			           "failed\n", tq_args[i]->name, tq_args[i]->id,
 			           sym2str(splat_taskq_test2_func1));
 			rc = -EINVAL;
 			break;
@@ -296,21 +302,21 @@ splat_taskq_test2_impl(struct file *file, void *arg, boolean_t prealloc) {
 
 		splat_vprint(file, SPLAT_TASKQ_TEST2_NAME,
 		           "Taskq '%s/%d' function '%s' dispatching\n",
-			   tq_args[i].name, tq_args[i].id,
+			   tq_args[i]->name, tq_args[i]->id,
 		           sym2str(splat_taskq_test2_func2));
 		if (prealloc) {
 			taskq_dispatch_ent(tq[i], splat_taskq_test2_func2,
-			                &tq_args[i], TQ_SLEEP, &func2_tqes[i]);
+			    tq_args[i], TQ_SLEEP, &func2_tqes[i]);
 			id = func2_tqes[i].tqent_id;
 		} else {
 			id = taskq_dispatch(tq[i], splat_taskq_test2_func2,
-			                    &tq_args[i], TQ_SLEEP);
+			    tq_args[i], TQ_SLEEP);
 		}
 
 		if (id == 0) {
 			splat_vprint(file, SPLAT_TASKQ_TEST2_NAME, "Taskq "
 				     "'%s/%d' function '%s' dispatch failed\n",
-			             tq_args[i].name, tq_args[i].id,
+			             tq_args[i]->name, tq_args[i]->id,
 			             sym2str(splat_taskq_test2_func2));
 			rc = -EINVAL;
 			break;
@@ -320,31 +326,36 @@ splat_taskq_test2_impl(struct file *file, void *arg, boolean_t prealloc) {
 	/* When rc is set we're effectively just doing cleanup here, so
 	 * ignore new errors in that case.  They just cause noise. */
 	for (i = 0; i < TEST2_TASKQS; i++) {
+		if (tq_args[i] == NULL)
+			continue;
+
 		if (tq[i] != NULL) {
 			splat_vprint(file, SPLAT_TASKQ_TEST2_NAME,
 			           "Taskq '%s/%d' waiting\n",
-			           tq_args[i].name, tq_args[i].id);
+			           tq_args[i]->name, tq_args[i]->id);
 			taskq_wait(tq[i]);
 			splat_vprint(file, SPLAT_TASKQ_TEST2_NAME,
 			           "Taskq '%s/%d; destroying\n",
-			          tq_args[i].name, tq_args[i].id);
+			          tq_args[i]->name, tq_args[i]->id);
 
 			taskq_destroy(tq[i]);
 
-			if (!rc && tq_args[i].flag != ((i * 2) + 1)) {
+			if (!rc && tq_args[i]->flag != ((i * 2) + 1)) {
 				splat_vprint(file, SPLAT_TASKQ_TEST2_NAME,
 				           "Taskq '%s/%d' processed tasks "
 				           "out of order; %d != %d\n",
-				           tq_args[i].name, tq_args[i].id,
-				           tq_args[i].flag, i * 2 + 1);
+				           tq_args[i]->name, tq_args[i]->id,
+				           tq_args[i]->flag, i * 2 + 1);
 				rc = -EINVAL;
 			} else {
 				splat_vprint(file, SPLAT_TASKQ_TEST2_NAME,
 				           "Taskq '%s/%d' processed tasks "
 					   "in the correct order; %d == %d\n",
-				           tq_args[i].name, tq_args[i].id,
-				           tq_args[i].flag, i * 2 + 1);
+				           tq_args[i]->name, tq_args[i]->id,
+				           tq_args[i]->flag, i * 2 + 1);
 			}
+
+			kfree(tq_args[i]);
 		}
 	}
 out: