staging: bcm2835-audio: fix coding style issues
Subsystems (3)
v4 cover staging: bcm2835-audio: fix coding style issues
This patch has the following fixes:
-- Replace kmalloc and memset with kzalloc vc_vchi_audio_init(..) -- Replace null return value with PTR_ERR(..) values in
vc_vchi_audio_init(..)
-- Propagate the PTR_ERR values forward instead of a hardcoded
value for easier debugging in bcm2835_audio_open_connection(..)
-- Replace if (success) else { } after kmalloc with if(error)
to fail fast in the work function
-- De-allocate 'work' when queue_work(..) fails in the work
functions
-- Add current function names __func__ to debug and error logs in the
work functions
-- De-allocate 'vchi_instance' when VCHI connection fails or VCHI audio
instance initialisation fails in bcm2835_audio_open_connection()
-- Remove BUG_ON() in bcm2835_audio_open_connection()
Changes in v4:
-- Break-up patch 4 into four smaller patches
-- Add a patch proposing removal of BUG_ON()
-- Make the cover letter verbose
Changes in v3:
-- Fix memory leak when queue_work fails
-- Add __func__ to debug logs
Changes in v2:
-- Return error value -EBUSY instead of -1 when queue_work()
fails
Aishwarya Pant (8):
staging: bcm2835-audio: Replace kmalloc with kzalloc
staging: bcm2835-audio: replace null with error pointer value
staging: bcm2835-audio: propagate PTR_ERR value instead of -EPERM
staging: bcm2835-audio: use conditional only for error case
staging: bcm2835-audio: deallocate work when queue_work(...) fails
staging: bcm2835-audio: Add function name to debug and error logs
staging: bcm2835-audio: fix memory leak in
bcm2835_audio_open_connection()
staging: bcm2835-audio: remove BUG_ON() in
bcm2835_audio_open_connection().../vc04_services/bcm2835-audio/bcm2835-vchiq.c | 109 +++++++++++---------- 1 file changed, 56 insertions(+), 53 deletions(-)
Signature · 1 line
2.7.4
PATCH v4 1/8 staging: bcm2835-audio: Replace kmalloc with kzalloc
Replace kmalloc and memset with kzalloc.
--- drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c +1 -2
@@ -290,11 +290,10 @@ vc_vchi_audio_init(VCHI_INSTANCE_T vchi_instance,return NULL ; }/* Allocate memory for this instance */ - instance =kmalloc (sizeof (*instance),GFP_KERNEL ); + instance =kzalloc (sizeof (*instance),GFP_KERNEL );if (!instance)return NULL ; -memset (instance,0 ,sizeof (*instance)); instance->num_connections = num_connections;/* Create a lock for exclusive, serialized VCHI connection access */
Signature · 1 line
2.7.4
PATCH v4 2/8 staging: bcm2835-audio: replace null with error pointer value
In reply to Aishwarya PantThis patch replaces NULL values returned by vc_vchi_audio_init(...) with error pointer values:
- Return ERR_PTR(-EINVAL) when too many instances of audio service are initialised
- Return ERR_PTR(-ENOMEM) when kzalloc fails
- RETURN ERR_PTR(-EPERM) when vchi connections fail to open
Similarly, a NULL check where vc_vchi_audio_init(...) is called is replaced by IS_ERR(..)
--- drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c +4 -4
@@ -287,12 +287,12 @@ vc_vchi_audio_init(VCHI_INSTANCE_T vchi_instance,LOG_ERR ("%s: unsupported number of connections %u (max=%u)\n" , __func__, num_connections,VCHI_MAX_NUM_CONNECTIONS ); -return NULL ; +return ERR_PTR (-EINVAL ); }/* Allocate memory for this instance */ instance =kzalloc (sizeof (*instance),GFP_KERNEL );if (!instance) -return NULL ; +return ERR_PTR (-ENOMEM ); instance->num_connections = num_connections;
@@ -341,7 +341,7 @@ vc_vchi_audio_init(VCHI_INSTANCE_T vchi_instance,kfree (instance);LOG_ERR ("%s: error\n" , __func__); -return NULL ; +return ERR_PTR (-EPERM ); }static int vc_vchi_audio_deinit (struct bcm2835_audio_instance *instance)
@@ -432,7 +432,7 @@ static int bcm2835_audio_open_connection(struct bcm2835_alsa_stream *alsa_stream/* Initialize an instance of the audio service */ instance =vc_vchi_audio_init (vchi_instance, &vchi_connection,1 ); -if (!instance) { +if (IS_ERR (instance)) {LOG_ERR ("%s: failed to initialize audio service\n" , __func__); ret = -EPERM ;
Signature · 1 line
2.7.4
PATCH v4 3/8 staging: bcm2835-audio: propagate PTR_ERR value instead of -EPERM
In reply to Aishwarya PantIt is better to propagate PTR_ERR value instead of a hardcoded value (-EPERM here)
--- drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c +1 -1
@@ -435,7 +435,7 @@ static int bcm2835_audio_open_connection(struct bcm2835_alsa_stream *alsa_streamif (IS_ERR (instance)) {LOG_ERR ("%s: failed to initialize audio service\n" , __func__); - ret = -EPERM ; + ret =PTR_ERR (instance); goto err_free_mem; }
Signature · 1 line
2.7.4
PATCH v4 4/8 staging: bcm2835-audio: use conditional only for error case
In reply to Aishwarya Pant* Refactor conditional to check if memory allocation has failed and immediately return (-ENOMEM); if block for success case is removed.
* Return the error value -EBUSY when queue_work() fails.
---
Changes in v4:
- Break up the patch into smaller changes
Changes in v3:
- Deallocate work when queue_work fails
- Add __func__ to debug logs
Changes in v2:
- Return error value -EBUSY when queue_work fails
.../vc04_services/bcm2835-audio/bcm2835-vchiq.c | 67 +++++++++++----------- 1 file changed, 32 insertions(+), 35 deletions(-)
drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c +32 -35
@@ -131,77 +131,74 @@ static void my_wq_function(struct work_struct *work)int bcm2835_audio_start (struct bcm2835_alsa_stream *alsa_stream) { -int ret =-1 ; -LOG_DBG (" .. IN\n" );if (alsa_stream->my_wq) {struct bcm2835_audio_work *work; work =kmalloc (sizeof (*work),GFP_ATOMIC );/*--- Queue some work (item 1) ---*/ -if (work) { -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)) - ret =0 ; - }else { +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)) { +return -EBUSY ; } } -LOG_DBG (" .. OUT %d\n" , ret); -return ret; +LOG_DBG (" .. OUT\n" ); +return 0 ; }int bcm2835_audio_stop (struct bcm2835_alsa_stream *alsa_stream) { -int ret =-1 ; -LOG_DBG (" .. IN\n" );if (alsa_stream->my_wq) {struct bcm2835_audio_work *work; work =kmalloc (sizeof (*work),GFP_ATOMIC );/*--- Queue some work (item 1) ---*/ -if (work) { -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)) - ret =0 ; - }else { +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)) { +return -EBUSY ; } } -LOG_DBG (" .. OUT %d\n" , ret); -return ret; +LOG_DBG (" .. OUT\n" ); +return 0 ; }int bcm2835_audio_write (struct bcm2835_alsa_stream *alsa_stream,unsigned int count,void *src) { -int ret =-1 ; -LOG_DBG (" .. IN\n" );if (alsa_stream->my_wq) {struct bcm2835_audio_work *work; work =kmalloc (sizeof (*work),GFP_ATOMIC );/*--- Queue some work (item 1) ---*/ -if (work) { -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)) - ret =0 ; - }else { +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)) { +return -EBUSY ; } } -LOG_DBG (" .. OUT %d\n" , ret); -return ret; +LOG_DBG (" .. OUT\n" ); +return 0 ; }static void my_workqueue_init (struct bcm2835_alsa_stream *alsa_stream)
Signature · 1 line
2.7.4
PATCH v4 5/8 staging: bcm2835-audio: deallocate work when queue_work(...) fails
In reply to Aishwarya PantThis patch de-allocates work when queue_work(..) fails in the bcm2835-audio work functions
--- drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c | 3 +++ 1 file changed, 3 insertions(+)
drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c +3 -0
@@ -145,6 +145,7 @@ int bcm2835_audio_start(struct bcm2835_alsa_stream *alsa_stream) work->alsa_stream = alsa_stream; work->cmd =BCM2835_AUDIO_START ;if (!queue_work (alsa_stream->my_wq, &work->my_work)) { +kfree (work);return -EBUSY ; } }
@@ -168,6 +169,7 @@ int bcm2835_audio_stop(struct bcm2835_alsa_stream *alsa_stream) work->alsa_stream = alsa_stream; work->cmd =BCM2835_AUDIO_STOP ;if (!queue_work (alsa_stream->my_wq, &work->my_work)) { +kfree (work);return -EBUSY ; } }
@@ -194,6 +196,7 @@ int bcm2835_audio_write(struct bcm2835_alsa_stream *alsa_stream, work->src = src; work->count = count;if (!queue_work (alsa_stream->my_wq, &work->my_work)) { +kfree (work);return -EBUSY ; } }
Signature · 1 line
2.7.4
PATCH v4 6/8 staging: bcm2835-audio: Add function name to debug and error logs
In reply to Aishwarya PantThis patch adds current function names __func__ to debug and error logs in the work functions.
--- .../staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-)
drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c +9 -6
@@ -138,7 +138,7 @@ int bcm2835_audio_start(struct bcm2835_alsa_stream *alsa_stream) work =kmalloc (sizeof (*work),GFP_ATOMIC );/*--- Queue some work (item 1) ---*/ if (!work) { -LOG_ERR (" .. Error: NULL work kmalloc\n" ); +LOG_ERR ("%s: Error: NULL work kmalloc\n" , __func__);return -ENOMEM ; }INIT_WORK (&work->my_work, my_wq_function);
@@ -146,10 +146,11 @@ int bcm2835_audio_start(struct bcm2835_alsa_stream *alsa_stream) work->cmd =BCM2835_AUDIO_START ;if (!queue_work (alsa_stream->my_wq, &work->my_work)) {kfree (work); +LOG_ERR ("%s: Error: Unable to start audio\n" , __func__);return -EBUSY ; } } -LOG_DBG (" .. OUT\n" ); +LOG_DBG ("%s: .. OUT\n" , __func__);return 0 ; }
@@ -162,7 +163,7 @@ int bcm2835_audio_stop(struct bcm2835_alsa_stream *alsa_stream) work =kmalloc (sizeof (*work),GFP_ATOMIC );/*--- Queue some work (item 1) ---*/ if (!work) { -LOG_ERR (" .. Error: NULL work kmalloc\n" ); +LOG_ERR ("%s: Error: NULL work kmalloc\n" , __func__);return -ENOMEM ; }INIT_WORK (&work->my_work, my_wq_function);
@@ -170,10 +171,11 @@ int bcm2835_audio_stop(struct bcm2835_alsa_stream *alsa_stream) work->cmd =BCM2835_AUDIO_STOP ;if (!queue_work (alsa_stream->my_wq, &work->my_work)) {kfree (work); +LOG_ERR ("%s: Error: Unable to stop audio\n" , __func__);return -EBUSY ; } } -LOG_DBG (" .. OUT\n" ); +LOG_DBG ("%s: .. OUT\n" , __func__);return 0 ; }
@@ -187,7 +189,7 @@ int bcm2835_audio_write(struct bcm2835_alsa_stream *alsa_stream, work =kmalloc (sizeof (*work),GFP_ATOMIC );/*--- Queue some work (item 1) ---*/ if (!work) { -LOG_ERR (" .. Error: NULL work kmalloc\n" ); +LOG_ERR ("%s: Error: NULL work kmalloc\n" , __func__);return -ENOMEM ; }INIT_WORK (&work->my_work, my_wq_function);
@@ -197,10 +199,11 @@ int bcm2835_audio_write(struct bcm2835_alsa_stream *alsa_stream, work->count = count;if (!queue_work (alsa_stream->my_wq, &work->my_work)) {kfree (work); +LOG_ERR ("%s: Error: Unable to write\n" , __func__);return -EBUSY ; } } -LOG_DBG (" .. OUT\n" ); +LOG_DBG ("%s: .. OUT\n" , __func__);return 0 ; }
Signature · 1 line
2.7.4
PATCH v4 7/8 staging: bcm2835-audio: fix memory leak in bcm2835_audio_open_connection()
In reply to Aishwarya PantIn bcm2835_audio_open_connection(), if VCHI connection fails or initialisation of VCHI audio instance fails vchi_instance needs to be deallocated otherwise it will cause a memory leak.
--- .../staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-)
drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c +8 -6
@@ -408,7 +408,7 @@ static int bcm2835_audio_open_connection(struct bcm2835_alsa_stream *alsa_stream instance->alsa_stream = alsa_stream; alsa_stream->instance = instance; ret =0 ;// xxx todo -1; - goto err_free_mem; + goto err_init; }/* Initialize and create a VCHI connection */
@@ -419,7 +419,7 @@ static int bcm2835_audio_open_connection(struct bcm2835_alsa_stream *alsa_stream __func__, ret); ret = -EIO ; - goto err_free_mem; + goto err_init; } ret =vchi_connect (NULL ,0 , vchi_instance);if (ret) {
@@ -427,7 +427,7 @@ static int bcm2835_audio_open_connection(struct bcm2835_alsa_stream *alsa_stream __func__, ret); ret = -EIO ; - goto err_free_mem; + goto err_free_memory; } initted =1 ; }
@@ -439,7 +439,7 @@ static int bcm2835_audio_open_connection(struct bcm2835_alsa_stream *alsa_streamLOG_ERR ("%s: failed to initialize audio service\n" , __func__); ret =PTR_ERR (instance); - goto err_free_mem; + goto err_free_memory; } instance->alsa_stream = alsa_stream;
@@ -447,9 +447,11 @@ static int bcm2835_audio_open_connection(struct bcm2835_alsa_stream *alsa_streamLOG_DBG (" success !\n" ); ret =0 ; -err_free_mem: +err_init:LOG_DBG (" .. OUT\n" ); - +return ret; +err_free_memory: +kfree (vchi_instance);return ret; }
Signature · 1 line
2.7.4
PATCH v4 8/8 staging: bcm2835-audio: remove BUG_ON() in bcm2835_audio_open_connection()
In reply to Aishwarya PantThe presence of BUG_ON(instance) in bcm2835_audio_open_connection() makes the next if(instance) block unreachable. The desired behaviour is that the function should exit gracefully returning an operation not permitted error value (-EPERM).
---
Not sure of this change. This driver is still in staging so maybe then BUG_ON() is required here for debugging. The kernel coding style document suggests that BUG_ON() should never be used since it kills the current process.
--- drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c +1 -2
@@ -401,13 +401,12 @@ static int bcm2835_audio_open_connection(struct bcm2835_alsa_stream *alsa_streamLOG_DBG (" .. IN\n" );LOG_INFO ("%s: start\n" , __func__); -BUG_ON (instance);if (instance) {LOG_ERR ("%s: VCHI instance already open (%p)\n" , __func__, instance); instance->alsa_stream = alsa_stream; alsa_stream->instance = instance; - ret =0 ;// xxx todo -1; + ret = -EPERM ; goto err_init; }
Signature · 1 line
2.7.4
Re: [PATCH v4 6/8] staging: bcm2835-audio: Add function name to debug and error logs
In reply to Aishwarya PantQuoted 66 lines · Aishwarya Pant
This patch adds current function names
__func__to debug and error logs in the work functions.Signed-off-by Aishwarya Pant <[email protected]>--- .../staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-)drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c +7
-5@@ -138,7 +138,7 @@ int bcm2835_audio_start(struct bcm2835_alsa_stream *alsa_stream) work =kmalloc (sizeof (*work),GFP_ATOMIC );/*--- Queue some work (item 1) ---*/ if (!work) { -LOG_ERR (" .. Error: NULL work kmalloc\n" ); +LOG_ERR ("%s: Error: NULL work kmalloc\n" , __func__);return -ENOMEM ; }INIT_WORK (&work->my_work, my_wq_function);@@ -146,10 +146,11 @@ int bcm2835_audio_start(struct bcm2835_alsa_stream *alsa_stream) work->cmd =BCM2835_AUDIO_START ;if (!queue_work (alsa_stream->my_wq, &work->my_work)) {kfree (work); +LOG_ERR ("%s: Error: Unable to start audio\n" , __func__);return -EBUSY ; } } -LOG_DBG (" .. OUT\n" ); +LOG_DBG ("%s: .. OUT\n" , __func__);return 0 ; }@@ -162,7 +163,7 @@ int bcm2835_audio_stop(struct bcm2835_alsa_stream *alsa_stream) work =kmalloc (sizeof (*work),GFP_ATOMIC );/*--- Queue some work (item 1) ---*/ if (!work) { -LOG_ERR (" .. Error: NULL work kmalloc\n" ); +LOG_ERR ("%s: Error: NULL work kmalloc\n" , __func__);return -ENOMEM ; }INIT_WORK (&work->my_work, my_wq_function);@@ -170,10 +171,11 @@ int bcm2835_audio_stop(struct bcm2835_alsa_stream *alsa_stream) work->cmd =BCM2835_AUDIO_STOP ;if (!queue_work (alsa_stream->my_wq, &work->my_work)) {kfree (work); +LOG_ERR ("%s: Error: Unable to stop audio\n" , __func__);return -EBUSY ; } } -LOG_DBG (" .. OUT\n" ); +LOG_DBG ("%s: .. OUT\n" , __func__);return 0 ; }@@ -187,7 +189,7 @@ int bcm2835_audio_write(struct bcm2835_alsa_stream *alsa_stream, work =kmalloc (sizeof (*work),GFP_ATOMIC );/*--- Queue some work (item 1) ---*/ if (!work) { -LOG_ERR (" .. Error: NULL work kmalloc\n" ); +LOG_ERR ("%s: Error: NULL work kmalloc\n" , __func__);return -ENOMEM ; }INIT_WORK (&work->my_work, my_wq_function);
drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c int bcm2835_audio_write(struct bcm2835_alsa_stream *alsa_stream, · line 206
Quoted 9 lines
drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c +2
-1@@ -197,10 +199,11 @@ int bcm2835_audio_write(struct bcm2835_alsa_stream *alsa_stream, work->count = count;if (!queue_work (alsa_stream->my_wq, &work->my_work)) {kfree (work); +LOG_ERR ("%s: Error: Unable to write\n" , __func__);return -EBUSY ; } } -LOG_DBG (" .. OUT\n" ); +LOG_DBG ("%s: .. OUT\n" , __func__);
Please ignore this patch.
LOG_DBG/ERR/INFO(..) are wrappers around pr_*(..) family with line number and function name appended. I'll send a new patchset with these changes reverted.
Quoted 6 lines
drivers/staging/vc04_services/bcm2835-audio/bcm2835-vchiq.c +0
-0return 0 ; }Signature · 1 line
2.7.4