dmatest: add a 'wait' parameter
Allows for scripting test runs by module load / unload. Prevent module
load from returning until 'iterations' (finite) tests have completed, or
cause reads of the 'wait' parameter in sysfs to pause until the tests
are done.
Also killed the local waitqueue since we can just let the thread exit
naturally as long as we hold a reference.
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c
index 26b5020..dd4d84d 100644
--- a/drivers/dma/dmatest.c
+++ b/drivers/dma/dmatest.c
@@ -161,6 +161,43 @@
struct list_head threads;
};
+static DECLARE_WAIT_QUEUE_HEAD(thread_wait);
+static bool wait;
+
+static bool is_threaded_test_run(struct dmatest_info *info)
+{
+ struct dmatest_chan *dtc;
+
+ list_for_each_entry(dtc, &info->channels, node) {
+ struct dmatest_thread *thread;
+
+ list_for_each_entry(thread, &dtc->threads, node) {
+ if (!thread->done)
+ return true;
+ }
+ }
+
+ return false;
+}
+
+static int dmatest_wait_get(char *val, const struct kernel_param *kp)
+{
+ struct dmatest_info *info = &test_info;
+ struct dmatest_params *params = &info->params;
+
+ if (params->iterations)
+ wait_event(thread_wait, !is_threaded_test_run(info));
+ wait = true;
+ return param_get_bool(val, kp);
+}
+
+static struct kernel_param_ops wait_ops = {
+ .get = dmatest_wait_get,
+ .set = param_set_bool,
+};
+module_param_cb(wait, &wait_ops, &wait, S_IRUGO);
+MODULE_PARM_DESC(wait, "Wait for tests to complete (default: false)");
+
static bool dmatest_match_channel(struct dmatest_params *params,
struct dma_chan *chan)
{
@@ -660,12 +697,7 @@
dmaengine_terminate_all(chan);
thread->done = true;
-
- if (params->iterations > 0)
- while (!kthread_should_stop()) {
- DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wait_dmatest_exit);
- interruptible_sleep_on(&wait_dmatest_exit);
- }
+ wake_up(&thread_wait);
return ret;
}
@@ -681,6 +713,7 @@
pr_debug("thread %s exited with status %d\n",
thread->task->comm, ret);
list_del(&thread->node);
+ put_task_struct(thread->task);
kfree(thread);
}
@@ -719,18 +752,19 @@
thread->chan = dtc->chan;
thread->type = type;
smp_wmb();
- thread->task = kthread_run(dmatest_func, thread, "%s-%s%u",
+ thread->task = kthread_create(dmatest_func, thread, "%s-%s%u",
dma_chan_name(chan), op, i);
if (IS_ERR(thread->task)) {
- pr_warn("Failed to run thread %s-%s%u\n",
+ pr_warn("Failed to create thread %s-%s%u\n",
dma_chan_name(chan), op, i);
kfree(thread);
break;
}
/* srcbuf and dstbuf are allocated by the thread itself */
-
+ get_task_struct(thread->task);
list_add_tail(&thread->node, &dtc->threads);
+ wake_up_process(thread->task);
}
return i;
@@ -863,22 +897,6 @@
run_threaded_test(info);
}
-static bool is_threaded_test_run(struct dmatest_info *info)
-{
- struct dmatest_chan *dtc;
-
- list_for_each_entry(dtc, &info->channels, node) {
- struct dmatest_thread *thread;
-
- list_for_each_entry(thread, &dtc->threads, node) {
- if (!thread->done)
- return true;
- }
- }
-
- return false;
-}
-
static int dmatest_run_get(char *val, const struct kernel_param *kp)
{
struct dmatest_info *info = &test_info;
@@ -920,6 +938,7 @@
static int __init dmatest_init(void)
{
struct dmatest_info *info = &test_info;
+ struct dmatest_params *params = &info->params;
if (dmatest_run) {
mutex_lock(&info->lock);
@@ -927,6 +946,9 @@
mutex_unlock(&info->lock);
}
+ if (params->iterations && wait)
+ wait_event(thread_wait, !is_threaded_test_run(info));
+
/* module parameters are stable, inittime tests are started,
* let userspace take over 'run' control
*/