[PATCH 1/2] staging: bcm2835-audio: Check if workqueue allocation failed

From: Tuomas Tynkkynen
Date: Thu Jul 12 2018 - 17:54:48 EST


Currently, if allocating a workqueue fails, the driver will probe
successfully but it will silently do nothing, which is rather silly.
So instead bail out with -ENOMEM in bcm2835_audio_open() if
alloc_workqueue() fails, and remove the now pointless checks for a NULL
workqueue.

While at it, get rid of the rather pointless one-line function
my_workqueue_init().

Signed-off-by: Tuomas Tynkkynen <tuomas@xxxxxxxxxx>
---
.../vc04_services/bcm2835-audio/bcm2835-vchiq.c | 111 ++++++++++-----------
1 file changed, 50 insertions(+), 61 deletions(-)

diff --git a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c
index a4a48f31f1a3..85ed807bb873 100644
--- a/drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c
+++ b/drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c
@@ -118,44 +118,40 @@ static void my_wq_function(struct work_struct *work)

int bcm2835_audio_start(struct bcm2835_alsa_stream *alsa_stream)
{
- if (alsa_stream->my_wq) {
- struct bcm2835_audio_work *work;
-
- work = kmalloc(sizeof(*work), GFP_ATOMIC);
- /*--- Queue some work (item 1) ---*/
- if (!work) {
- LOG_ERR(" .. Error: NULL work kmalloc\n");
- return -ENOMEM;
- }
- INIT_WORK(&work->my_work, my_wq_function);
- work->alsa_stream = alsa_stream;
- work->cmd = BCM2835_AUDIO_START;
- if (!queue_work(alsa_stream->my_wq, &work->my_work)) {
- kfree(work);
- return -EBUSY;
- }
+ struct bcm2835_audio_work *work;
+
+ work = kmalloc(sizeof(*work), GFP_ATOMIC);
+ /*--- Queue some work (item 1) ---*/
+ if (!work) {
+ LOG_ERR(" .. Error: NULL work kmalloc\n");
+ return -ENOMEM;
+ }
+ INIT_WORK(&work->my_work, my_wq_function);
+ work->alsa_stream = alsa_stream;
+ work->cmd = BCM2835_AUDIO_START;
+ if (!queue_work(alsa_stream->my_wq, &work->my_work)) {
+ kfree(work);
+ return -EBUSY;
}
return 0;
}

int bcm2835_audio_stop(struct bcm2835_alsa_stream *alsa_stream)
{
- if (alsa_stream->my_wq) {
- struct bcm2835_audio_work *work;
-
- work = kmalloc(sizeof(*work), GFP_ATOMIC);
- /*--- Queue some work (item 1) ---*/
- if (!work) {
- LOG_ERR(" .. Error: NULL work kmalloc\n");
- return -ENOMEM;
- }
- INIT_WORK(&work->my_work, my_wq_function);
- work->alsa_stream = alsa_stream;
- work->cmd = BCM2835_AUDIO_STOP;
- if (!queue_work(alsa_stream->my_wq, &work->my_work)) {
- kfree(work);
- return -EBUSY;
- }
+ struct bcm2835_audio_work *work;
+
+ work = kmalloc(sizeof(*work), GFP_ATOMIC);
+ /*--- Queue some work (item 1) ---*/
+ if (!work) {
+ LOG_ERR(" .. Error: NULL work kmalloc\n");
+ return -ENOMEM;
+ }
+ INIT_WORK(&work->my_work, my_wq_function);
+ work->alsa_stream = alsa_stream;
+ work->cmd = BCM2835_AUDIO_STOP;
+ if (!queue_work(alsa_stream->my_wq, &work->my_work)) {
+ kfree(work);
+ return -EBUSY;
}
return 0;
}
@@ -163,40 +159,31 @@ int bcm2835_audio_stop(struct bcm2835_alsa_stream *alsa_stream)
int bcm2835_audio_write(struct bcm2835_alsa_stream *alsa_stream,
unsigned int count, void *src)
{
- if (alsa_stream->my_wq) {
- struct bcm2835_audio_work *work;
-
- work = kmalloc(sizeof(*work), GFP_ATOMIC);
- /*--- Queue some work (item 1) ---*/
- if (!work) {
- LOG_ERR(" .. Error: NULL work kmalloc\n");
- return -ENOMEM;
- }
- INIT_WORK(&work->my_work, my_wq_function);
- work->alsa_stream = alsa_stream;
- work->cmd = BCM2835_AUDIO_WRITE;
- work->src = src;
- work->count = count;
- if (!queue_work(alsa_stream->my_wq, &work->my_work)) {
- kfree(work);
- return -EBUSY;
- }
+ struct bcm2835_audio_work *work;
+
+ work = kmalloc(sizeof(*work), GFP_ATOMIC);
+ /*--- Queue some work (item 1) ---*/
+ if (!work) {
+ LOG_ERR(" .. Error: NULL work kmalloc\n");
+ return -ENOMEM;
+ }
+ INIT_WORK(&work->my_work, my_wq_function);
+ work->alsa_stream = alsa_stream;
+ work->cmd = BCM2835_AUDIO_WRITE;
+ work->src = src;
+ work->count = count;
+ if (!queue_work(alsa_stream->my_wq, &work->my_work)) {
+ kfree(work);
+ return -EBUSY;
}
return 0;
}

-static void my_workqueue_init(struct bcm2835_alsa_stream *alsa_stream)
-{
- alsa_stream->my_wq = alloc_workqueue("my_queue", WQ_HIGHPRI, 1);
-}
-
static void my_workqueue_quit(struct bcm2835_alsa_stream *alsa_stream)
{
- if (alsa_stream->my_wq) {
- flush_workqueue(alsa_stream->my_wq);
- destroy_workqueue(alsa_stream->my_wq);
- alsa_stream->my_wq = NULL;
- }
+ flush_workqueue(alsa_stream->my_wq);
+ destroy_workqueue(alsa_stream->my_wq);
+ alsa_stream->my_wq = NULL;
}

static void audio_vchi_callback(void *param,
@@ -424,7 +411,9 @@ int bcm2835_audio_open(struct bcm2835_alsa_stream *alsa_stream)
int status;
int ret;

- my_workqueue_init(alsa_stream);
+ alsa_stream->my_wq = alloc_workqueue("my_queue", WQ_HIGHPRI, 1);
+ if (!alsa_stream->my_wq)
+ return -ENOMEM;

ret = bcm2835_audio_open_connection(alsa_stream);
if (ret) {
--
2.16.3