2018-05-10 23:31:38

by Eric Anholt

[permalink] [raw]
Subject: [PATCH] staging: bcm2835-camera: Replace open-coded idr with a struct idr.

We just need some integer handles that can map back to our message
struct when we're handling a reply, which struct idr is perfect for.

Signed-off-by: Eric Anholt <[email protected]>
---
.../vc04_services/bcm2835-camera/mmal-vchiq.c | 135 ++++--------------
1 file changed, 31 insertions(+), 104 deletions(-)

diff --git a/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c b/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c
index 3a3b843fc122..f0dac6440cfb 100644
--- a/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c
+++ b/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c
@@ -21,7 +21,6 @@
#include <linux/slab.h>
#include <linux/completion.h>
#include <linux/vmalloc.h>
-#include <linux/btree.h>
#include <asm/cacheflush.h>
#include <media/videobuf2-vmalloc.h>

@@ -111,7 +110,11 @@ struct vchiq_mmal_instance;
/* normal message context */
struct mmal_msg_context {
struct vchiq_mmal_instance *instance;
- u32 handle;
+
+ /* Index in the context_map idr so that we can find the
+ * mmal_msg_context again when servicing the VCHI reply.
+ */
+ int handle;

union {
struct {
@@ -149,13 +152,6 @@ struct mmal_msg_context {

};

-struct vchiq_mmal_context_map {
- /* ensure serialized access to the btree(contention should be low) */
- struct mutex lock;
- struct btree_head32 btree_head;
- u32 last_handle;
-};
-
struct vchiq_mmal_instance {
VCHI_SERVICE_HANDLE_T handle;

@@ -165,92 +161,19 @@ struct vchiq_mmal_instance {
/* vmalloc page to receive scratch bulk xfers into */
void *bulk_scratch;

- /* mapping table between context handles and mmal_msg_contexts */
- struct vchiq_mmal_context_map context_map;
+ struct idr context_map;
+ spinlock_t context_map_lock;

/* component to use next */
int component_idx;
struct vchiq_mmal_component component[VCHIQ_MMAL_MAX_COMPONENTS];
};

-static int __must_check
-mmal_context_map_init(struct vchiq_mmal_context_map *context_map)
-{
- mutex_init(&context_map->lock);
- context_map->last_handle = 0;
- return btree_init32(&context_map->btree_head);
-}
-
-static void mmal_context_map_destroy(struct vchiq_mmal_context_map *context_map)
-{
- mutex_lock(&context_map->lock);
- btree_destroy32(&context_map->btree_head);
- mutex_unlock(&context_map->lock);
-}
-
-static u32
-mmal_context_map_create_handle(struct vchiq_mmal_context_map *context_map,
- struct mmal_msg_context *msg_context,
- gfp_t gfp)
-{
- u32 handle;
-
- mutex_lock(&context_map->lock);
-
- while (1) {
- /* just use a simple count for handles, but do not use 0 */
- context_map->last_handle++;
- if (!context_map->last_handle)
- context_map->last_handle++;
-
- handle = context_map->last_handle;
-
- /* check if the handle is already in use */
- if (!btree_lookup32(&context_map->btree_head, handle))
- break;
- }
-
- if (btree_insert32(&context_map->btree_head, handle,
- msg_context, gfp)) {
- /* probably out of memory */
- mutex_unlock(&context_map->lock);
- return 0;
- }
-
- mutex_unlock(&context_map->lock);
- return handle;
-}
-
-static struct mmal_msg_context *
-mmal_context_map_lookup_handle(struct vchiq_mmal_context_map *context_map,
- u32 handle)
-{
- struct mmal_msg_context *msg_context;
-
- if (!handle)
- return NULL;
-
- mutex_lock(&context_map->lock);
-
- msg_context = btree_lookup32(&context_map->btree_head, handle);
-
- mutex_unlock(&context_map->lock);
- return msg_context;
-}
-
-static void
-mmal_context_map_destroy_handle(struct vchiq_mmal_context_map *context_map,
- u32 handle)
-{
- mutex_lock(&context_map->lock);
- btree_remove32(&context_map->btree_head, handle);
- mutex_unlock(&context_map->lock);
-}
-
static struct mmal_msg_context *
get_msg_context(struct vchiq_mmal_instance *instance)
{
struct mmal_msg_context *msg_context;
+ int handle;

/* todo: should this be allocated from a pool to avoid kzalloc */
msg_context = kzalloc(sizeof(*msg_context), GFP_KERNEL);
@@ -258,32 +181,40 @@ get_msg_context(struct vchiq_mmal_instance *instance)
if (!msg_context)
return ERR_PTR(-ENOMEM);

- msg_context->instance = instance;
- msg_context->handle =
- mmal_context_map_create_handle(&instance->context_map,
- msg_context,
- GFP_KERNEL);
+ /* Create an ID that will be passed along with our message so
+ * that when we service the VCHI reply, we can look up what
+ * message is being replied to.
+ */
+ spin_lock(&instance->context_map_lock);
+ handle = idr_alloc(&instance->context_map, msg_context,
+ 0, 0, GFP_KERNEL);
+ spin_unlock(&instance->context_map_lock);

- if (!msg_context->handle) {
+ if (msg_context->handle < 0) {
kfree(msg_context);
- return ERR_PTR(-ENOMEM);
+ return ERR_PTR(handle);
}

+ msg_context->instance = instance;
+ msg_context->handle = handle;
+
return msg_context;
}

static struct mmal_msg_context *
-lookup_msg_context(struct vchiq_mmal_instance *instance, u32 handle)
+lookup_msg_context(struct vchiq_mmal_instance *instance, int handle)
{
- return mmal_context_map_lookup_handle(&instance->context_map,
- handle);
+ return idr_find(&instance->context_map, handle);
}

static void
release_msg_context(struct mmal_msg_context *msg_context)
{
- mmal_context_map_destroy_handle(&msg_context->instance->context_map,
- msg_context->handle);
+ struct vchiq_mmal_instance *instance = msg_context->instance;
+
+ spin_lock(&instance->context_map_lock);
+ idr_remove(&instance->context_map, msg_context->handle);
+ spin_unlock(&instance->context_map_lock);
kfree(msg_context);
}

@@ -1860,7 +1791,7 @@ int vchiq_mmal_finalise(struct vchiq_mmal_instance *instance)

vfree(instance->bulk_scratch);

- mmal_context_map_destroy(&instance->context_map);
+ idr_destroy(&instance->context_map);

kfree(instance);

@@ -1922,12 +1853,8 @@ int vchiq_mmal_init(struct vchiq_mmal_instance **out_instance)

instance->bulk_scratch = vmalloc(PAGE_SIZE);

- status = mmal_context_map_init(&instance->context_map);
- if (status) {
- pr_err("Failed to init context map (status=%d)\n", status);
- kfree(instance);
- return status;
- }
+ spin_lock_init(&instance->context_map_lock);
+ idr_init_base(&instance->context_map, 1);

params.callback_param = instance;

--
2.17.0



2018-05-10 23:41:13

by Stefan Wahren

[permalink] [raw]
Subject: Re: [PATCH] staging: bcm2835-camera: Replace open-coded idr with a struct idr.

Hi Eric,

> Eric Anholt <[email protected]> hat am 11. Mai 2018 um 01:31 geschrieben:
>
>
> We just need some integer handles that can map back to our message
> struct when we're handling a reply, which struct idr is perfect for.
>
> Signed-off-by: Eric Anholt <[email protected]>
> ---
> .../vc04_services/bcm2835-camera/mmal-vchiq.c | 135 ++++--------------
> 1 file changed, 31 insertions(+), 104 deletions(-)
>
> diff --git a/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c b/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c
> index 3a3b843fc122..f0dac6440cfb 100644
> --- a/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c
> +++ b/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c
> @@ -21,7 +21,6 @@
> #include <linux/slab.h>
> #include <linux/completion.h>
> #include <linux/vmalloc.h>
> -#include <linux/btree.h>
> #include <asm/cacheflush.h>
> #include <media/videobuf2-vmalloc.h>
>
> @@ -111,7 +110,11 @@ struct vchiq_mmal_instance;
> /* normal message context */
> struct mmal_msg_context {
> struct vchiq_mmal_instance *instance;
> - u32 handle;
> +
> + /* Index in the context_map idr so that we can find the
> + * mmal_msg_context again when servicing the VCHI reply.
> + */
> + int handle;
>
> union {
> struct {
> @@ -149,13 +152,6 @@ struct mmal_msg_context {
>
> };
>
> -struct vchiq_mmal_context_map {
> - /* ensure serialized access to the btree(contention should be low) */
> - struct mutex lock;
> - struct btree_head32 btree_head;
> - u32 last_handle;
> -};
> -
> struct vchiq_mmal_instance {
> VCHI_SERVICE_HANDLE_T handle;
>
> @@ -165,92 +161,19 @@ struct vchiq_mmal_instance {
> /* vmalloc page to receive scratch bulk xfers into */
> void *bulk_scratch;
>
> - /* mapping table between context handles and mmal_msg_contexts */
> - struct vchiq_mmal_context_map context_map;
> + struct idr context_map;
> + spinlock_t context_map_lock;
>
> /* component to use next */
> int component_idx;
> struct vchiq_mmal_component component[VCHIQ_MMAL_MAX_COMPONENTS];
> };
>
> -static int __must_check
> -mmal_context_map_init(struct vchiq_mmal_context_map *context_map)
> -{
> - mutex_init(&context_map->lock);
> - context_map->last_handle = 0;
> - return btree_init32(&context_map->btree_head);
> -}
> -
> -static void mmal_context_map_destroy(struct vchiq_mmal_context_map *context_map)
> -{
> - mutex_lock(&context_map->lock);
> - btree_destroy32(&context_map->btree_head);
> - mutex_unlock(&context_map->lock);
> -}
> -
> -static u32
> -mmal_context_map_create_handle(struct vchiq_mmal_context_map *context_map,
> - struct mmal_msg_context *msg_context,
> - gfp_t gfp)
> -{
> - u32 handle;
> -
> - mutex_lock(&context_map->lock);
> -
> - while (1) {
> - /* just use a simple count for handles, but do not use 0 */
> - context_map->last_handle++;
> - if (!context_map->last_handle)
> - context_map->last_handle++;
> -
> - handle = context_map->last_handle;
> -
> - /* check if the handle is already in use */
> - if (!btree_lookup32(&context_map->btree_head, handle))
> - break;
> - }
> -
> - if (btree_insert32(&context_map->btree_head, handle,
> - msg_context, gfp)) {
> - /* probably out of memory */
> - mutex_unlock(&context_map->lock);
> - return 0;
> - }
> -
> - mutex_unlock(&context_map->lock);
> - return handle;
> -}
> -
> -static struct mmal_msg_context *
> -mmal_context_map_lookup_handle(struct vchiq_mmal_context_map *context_map,
> - u32 handle)
> -{
> - struct mmal_msg_context *msg_context;
> -
> - if (!handle)
> - return NULL;
> -
> - mutex_lock(&context_map->lock);
> -
> - msg_context = btree_lookup32(&context_map->btree_head, handle);
> -
> - mutex_unlock(&context_map->lock);
> - return msg_context;
> -}
> -
> -static void
> -mmal_context_map_destroy_handle(struct vchiq_mmal_context_map *context_map,
> - u32 handle)
> -{
> - mutex_lock(&context_map->lock);
> - btree_remove32(&context_map->btree_head, handle);
> - mutex_unlock(&context_map->lock);
> -}
> -
> static struct mmal_msg_context *
> get_msg_context(struct vchiq_mmal_instance *instance)
> {
> struct mmal_msg_context *msg_context;
> + int handle;
>
> /* todo: should this be allocated from a pool to avoid kzalloc */
> msg_context = kzalloc(sizeof(*msg_context), GFP_KERNEL);
> @@ -258,32 +181,40 @@ get_msg_context(struct vchiq_mmal_instance *instance)
> if (!msg_context)
> return ERR_PTR(-ENOMEM);
>
> - msg_context->instance = instance;
> - msg_context->handle =
> - mmal_context_map_create_handle(&instance->context_map,
> - msg_context,
> - GFP_KERNEL);
> + /* Create an ID that will be passed along with our message so
> + * that when we service the VCHI reply, we can look up what
> + * message is being replied to.
> + */
> + spin_lock(&instance->context_map_lock);
> + handle = idr_alloc(&instance->context_map, msg_context,
> + 0, 0, GFP_KERNEL);
> + spin_unlock(&instance->context_map_lock);
>
> - if (!msg_context->handle) {
> + if (msg_context->handle < 0) {

handle < 0 ?

> kfree(msg_context);
> - return ERR_PTR(-ENOMEM);
> + return ERR_PTR(handle);
> }
>
> + msg_context->instance = instance;
> + msg_context->handle = handle;
> +
> return msg_context;
> }
>

Regards
Stefan

2018-05-11 00:42:11

by Eric Anholt

[permalink] [raw]
Subject: Re: [PATCH] staging: bcm2835-camera: Replace open-coded idr with a struct idr.

Stefan Wahren <[email protected]> writes:

> Hi Eric,
>
>> Eric Anholt <[email protected]> hat am 11. Mai 2018 um 01:31 geschrieben:
>>
>>
>> We just need some integer handles that can map back to our message
>> struct when we're handling a reply, which struct idr is perfect for.
>>
>> Signed-off-by: Eric Anholt <[email protected]>
>> ---
>> .../vc04_services/bcm2835-camera/mmal-vchiq.c | 135 ++++--------------
>> 1 file changed, 31 insertions(+), 104 deletions(-)
>>
>> diff --git a/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c b/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c
>> index 3a3b843fc122..f0dac6440cfb 100644
>> --- a/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c
>> +++ b/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c
>> @@ -21,7 +21,6 @@
>> #include <linux/slab.h>
>> #include <linux/completion.h>
>> #include <linux/vmalloc.h>
>> -#include <linux/btree.h>
>> #include <asm/cacheflush.h>
>> #include <media/videobuf2-vmalloc.h>
>>
>> @@ -111,7 +110,11 @@ struct vchiq_mmal_instance;
>> /* normal message context */
>> struct mmal_msg_context {
>> struct vchiq_mmal_instance *instance;
>> - u32 handle;
>> +
>> + /* Index in the context_map idr so that we can find the
>> + * mmal_msg_context again when servicing the VCHI reply.
>> + */
>> + int handle;
>>
>> union {
>> struct {
>> @@ -149,13 +152,6 @@ struct mmal_msg_context {
>>
>> };
>>
>> -struct vchiq_mmal_context_map {
>> - /* ensure serialized access to the btree(contention should be low) */
>> - struct mutex lock;
>> - struct btree_head32 btree_head;
>> - u32 last_handle;
>> -};
>> -
>> struct vchiq_mmal_instance {
>> VCHI_SERVICE_HANDLE_T handle;
>>
>> @@ -165,92 +161,19 @@ struct vchiq_mmal_instance {
>> /* vmalloc page to receive scratch bulk xfers into */
>> void *bulk_scratch;
>>
>> - /* mapping table between context handles and mmal_msg_contexts */
>> - struct vchiq_mmal_context_map context_map;
>> + struct idr context_map;
>> + spinlock_t context_map_lock;
>>
>> /* component to use next */
>> int component_idx;
>> struct vchiq_mmal_component component[VCHIQ_MMAL_MAX_COMPONENTS];
>> };
>>
>> -static int __must_check
>> -mmal_context_map_init(struct vchiq_mmal_context_map *context_map)
>> -{
>> - mutex_init(&context_map->lock);
>> - context_map->last_handle = 0;
>> - return btree_init32(&context_map->btree_head);
>> -}
>> -
>> -static void mmal_context_map_destroy(struct vchiq_mmal_context_map *context_map)
>> -{
>> - mutex_lock(&context_map->lock);
>> - btree_destroy32(&context_map->btree_head);
>> - mutex_unlock(&context_map->lock);
>> -}
>> -
>> -static u32
>> -mmal_context_map_create_handle(struct vchiq_mmal_context_map *context_map,
>> - struct mmal_msg_context *msg_context,
>> - gfp_t gfp)
>> -{
>> - u32 handle;
>> -
>> - mutex_lock(&context_map->lock);
>> -
>> - while (1) {
>> - /* just use a simple count for handles, but do not use 0 */
>> - context_map->last_handle++;
>> - if (!context_map->last_handle)
>> - context_map->last_handle++;
>> -
>> - handle = context_map->last_handle;
>> -
>> - /* check if the handle is already in use */
>> - if (!btree_lookup32(&context_map->btree_head, handle))
>> - break;
>> - }
>> -
>> - if (btree_insert32(&context_map->btree_head, handle,
>> - msg_context, gfp)) {
>> - /* probably out of memory */
>> - mutex_unlock(&context_map->lock);
>> - return 0;
>> - }
>> -
>> - mutex_unlock(&context_map->lock);
>> - return handle;
>> -}
>> -
>> -static struct mmal_msg_context *
>> -mmal_context_map_lookup_handle(struct vchiq_mmal_context_map *context_map,
>> - u32 handle)
>> -{
>> - struct mmal_msg_context *msg_context;
>> -
>> - if (!handle)
>> - return NULL;
>> -
>> - mutex_lock(&context_map->lock);
>> -
>> - msg_context = btree_lookup32(&context_map->btree_head, handle);
>> -
>> - mutex_unlock(&context_map->lock);
>> - return msg_context;
>> -}
>> -
>> -static void
>> -mmal_context_map_destroy_handle(struct vchiq_mmal_context_map *context_map,
>> - u32 handle)
>> -{
>> - mutex_lock(&context_map->lock);
>> - btree_remove32(&context_map->btree_head, handle);
>> - mutex_unlock(&context_map->lock);
>> -}
>> -
>> static struct mmal_msg_context *
>> get_msg_context(struct vchiq_mmal_instance *instance)
>> {
>> struct mmal_msg_context *msg_context;
>> + int handle;
>>
>> /* todo: should this be allocated from a pool to avoid kzalloc */
>> msg_context = kzalloc(sizeof(*msg_context), GFP_KERNEL);
>> @@ -258,32 +181,40 @@ get_msg_context(struct vchiq_mmal_instance *instance)
>> if (!msg_context)
>> return ERR_PTR(-ENOMEM);
>>
>> - msg_context->instance = instance;
>> - msg_context->handle =
>> - mmal_context_map_create_handle(&instance->context_map,
>> - msg_context,
>> - GFP_KERNEL);
>> + /* Create an ID that will be passed along with our message so
>> + * that when we service the VCHI reply, we can look up what
>> + * message is being replied to.
>> + */
>> + spin_lock(&instance->context_map_lock);
>> + handle = idr_alloc(&instance->context_map, msg_context,
>> + 0, 0, GFP_KERNEL);
>> + spin_unlock(&instance->context_map_lock);
>>
>> - if (!msg_context->handle) {
>> + if (msg_context->handle < 0) {
>
> handle < 0 ?

You're right, thanks!


Attachments:
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2018-05-15 12:06:30

by Dan Carpenter

[permalink] [raw]
Subject: Re: [PATCH] staging: bcm2835-camera: Replace open-coded idr with a struct idr.

On Thu, May 10, 2018 at 04:31:07PM -0700, Eric Anholt wrote:
> @@ -258,32 +181,40 @@ get_msg_context(struct vchiq_mmal_instance *instance)
> if (!msg_context)
> return ERR_PTR(-ENOMEM);
>
> - msg_context->instance = instance;
> - msg_context->handle =
> - mmal_context_map_create_handle(&instance->context_map,
> - msg_context,
> - GFP_KERNEL);
> + /* Create an ID that will be passed along with our message so
> + * that when we service the VCHI reply, we can look up what
> + * message is being replied to.
> + */
> + spin_lock(&instance->context_map_lock);
> + handle = idr_alloc(&instance->context_map, msg_context,
> + 0, 0, GFP_KERNEL);
> + spin_unlock(&instance->context_map_lock);
>
> - if (!msg_context->handle) {
> + if (msg_context->handle < 0) {

This should probably be testing:

if (handle < 0) {

> kfree(msg_context);
> - return ERR_PTR(-ENOMEM);
> + return ERR_PTR(handle);
> }
>
> + msg_context->instance = instance;
> + msg_context->handle = handle;
> +
> return msg_context;
> }
>


2018-05-15 14:04:39

by Eric Anholt

[permalink] [raw]
Subject: Re: [PATCH] staging: bcm2835-camera: Replace open-coded idr with a struct idr.

Dan Carpenter <[email protected]> writes:

> On Thu, May 10, 2018 at 04:31:07PM -0700, Eric Anholt wrote:
>> @@ -258,32 +181,40 @@ get_msg_context(struct vchiq_mmal_instance *instance)
>> if (!msg_context)
>> return ERR_PTR(-ENOMEM);
>>
>> - msg_context->instance = instance;
>> - msg_context->handle =
>> - mmal_context_map_create_handle(&instance->context_map,
>> - msg_context,
>> - GFP_KERNEL);
>> + /* Create an ID that will be passed along with our message so
>> + * that when we service the VCHI reply, we can look up what
>> + * message is being replied to.
>> + */
>> + spin_lock(&instance->context_map_lock);
>> + handle = idr_alloc(&instance->context_map, msg_context,
>> + 0, 0, GFP_KERNEL);
>> + spin_unlock(&instance->context_map_lock);
>>
>> - if (!msg_context->handle) {
>> + if (msg_context->handle < 0) {
>
> This should probably be testing:
>
> if (handle < 0) {

That's what Stefan said and was fixed in v2 already.


Attachments:
signature.asc (847.00 B)