[PATCH] posix: Reimplement POSIX Key manager to use a red-black tree.

[Joel Sherrill]

Just checking in.. is all this work merged?

--joel

On 08/12/2013 08:32 AM, Gedare Bloom wrote:
> Good work Zhongwei! This was a good effort and will be useful for many
> in the future. I hope you can find other little RTEMS projects to work
> on as your time and interest permits.
>
> -Gedare
>
> On Sun, Aug 4, 2013 at 8:23 PM, Ashi <ashi08104 at gmail.com> wrote:
>> Here is the patch created by git format-patch.
>>
>> Cheers,
>> Zhongwei
>>
>>
>> On Sun, Aug 4, 2013 at 2:24 PM, Ashi <ashi08104 at gmail.com> wrote:
>>> Hi, All. The patch is updated according to Sebastian's comments.
>>>
>>> Cheers,
>>> Zhongwei
>>>
>>>
>>> On Fri, Aug 2, 2013 at 7:01 PM, Ashi <ashi08104 at gmail.com> wrote:
>>>>
>>>>
>>>>
>>>> On Fri, Aug 2, 2013 at 2:38 PM, Sebastian Huber
>>>> <sebastian.huber at embedded-brains.de> wrote:
>>>>> On 2013-08-02 03:03, Ashi wrote:
>>>>>>
>>>>>>          +  /** This field points to parent freechain node */
>>>>>>          +  POSIX_Keys_Freechain_node *fc_node_ptr;
>>>>>>
>>>>>>
>>>>>>      I don't think we need this fc_node_ptr.
>>>>>>
>>>>>> Do you mean use a 'Container' macro instead?
>>>>>
>>>>> Not necessarily, see below.
>>>>>
>>>>>>
>>>>>>          +  /** This field is the POSIX key used as an rbtree key */
>>>>>>          +  pthread_key_t key;
>>>>>>          +  /** This field is the Thread id also used as an rbtree key
>>>>>> */
>>>>>>          +  Objects_Id thread_id;
>>>>>>          +  /** This field points to the POSIX key value of specific
>>>>>> thread */
>>>>>>          +  void *value;
>>>>>>          +}  POSIX_Keys_Rbtree_node;
>>>>>>
>>>>>>
>>>>>>      I would call this POSIX_Keys_Key_value_pair.
>>>>>>
>>>>>>          +
>>>>>>          +/**
>>>>>>          + * @brief POSIX_Keys_Freechain is used in Freechain structure
>>>>>>          + */
>>>>>>          +typedef struct {
>>>>>>          +    Freechain_Control super_fc;
>>>>>>          +    size_t bump_count;
>>>>>>          +} POSIX_Keys_Freechain;
>>>>>>          +
>>>>>>          +/**
>>>>>>          + * @brief POSIX_Keys_Freechain_node is freechain node
>>>>>>          + */
>>>>>>          +struct POSIX_Keys_Freechain_node___struct {
>>>>>>
>>>>>>          +  Chain_Node ch_node;
>>>>>>          +  POSIX_Keys_Rbtree_node rb_node;
>>>>>>          +};
>>>>>>
>>>>>>
>>>>>>      Why not use POSIX_Keys_Rbtree_node directly?
>>>>>>
>>>>>> Since every freechain node needs a Chain_Node in its first field. There
>>>>>> is a
>>>>>> Chain_Node in  POSIX_Keys_Rbtree_node, but it is used in each thread's
>>>>>> key
>>>>>> value chain. So I add a Chain_Node to POSIX_Keys_Rbtree_node.
>>>>>
>>>>> The key value pairs on the free chain are unused, thus not part of other
>>>>> data structures.  So basically you can cast an unused object to any type
>>>>> provided it has enough storage.
>>>> Cool! I see. I didn't realise the whole key value pairs is actually
>>>> unused until it moves from Freechain to POSIX key value pair.
>>>>>
>>>>>
>>>>> --
>>>>> Sebastian Huber, embedded brains GmbH
>>>>>
>>>>> Address : Dornierstr. 4, D-82178 Puchheim, Germany
>>>>> Phone   : +49 89 189 47 41-16
>>>>> Fax     : +49 89 189 47 41-09
>>>>> E-Mail  : sebastian.huber at embedded-brains.de
>>>>> PGP     : Public key available on request.
>>>>>
>>>>> Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG.
>>>>


-- 
Joel Sherrill, Ph.D.             Director of Research& Development
joel.sherrill at OARcorp.com        On-Line Applications Research
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