Everything

get_mpf

Outline
Acquire fixed-sized memory block (waiting forever).
C format
 ER      get_mpf (ID mpfid, VP *p_blk);
Parameter(s)
I/O
Parameter
Description
I
 ID      mpfid;
ID number of the fixed-sized memory pool from which a memory block is acquired.
O
 VP      *p_blk;
Start address of the acquired memory block.

Explanation
This service call acquires the fixed-sized memory block from the fixed-sized memory pool specified by parameter mpfid and stores the start address in the area specified by parameter p_blk.
If no fixed-size memory blocks could be acquired from the target fixed-size memory pool (no available fixed-size memory blocks exist) when this service call is issued, this service call does not acquire the fixed-size memory block but queues the invoking task to the target fixed-size memory pool wait queue and moves it from the RUNNING state to the WAITING state (fixed-size memory block acquisition wait state).
The WAITING state for a fixed-sized memory block is cancelled in the following cases, and then moved to the READY state.
WAITING State for a Fixed-sized Memory Block Cancel Operation
Return Value
A fixed-sized memory block was returned to the target fixed-sized memory pool as a result of issuing rel_mpf.
E_OK
A fixed-sized memory block was returned to the target fixed-sized memory pool as a result of issuing irel_mpf.
E_OK
Forced release from waiting (accept rel_wai while waiting).
E_RLWAI
Forced release from waiting (accept irel_wai while waiting).
E_RLWAI

Note 1 The RI850V4 does not perform memory clear processing when acquiring a fixed-sized memory block. The contents of the acquired fixed-sized memory block are therefore undefined.
Note 2 Invoking tasks are queued to the target fixed-size memory pool wait queue in the order defined during configuration (FIFO order or priority order).
Note 3 If the fixed-size memory block acquisition wait state is cancelled because rel_wai or irel_wai was issued, the contents in the area specified by parameter p_blk become undefined.
Return value
Macro
Value
Description
E_OK
0
Normal completion.
E_ID
-18
Invalid ID number.
- mpfid < 0x0
- mpfid > Maximum ID number
E_CTX
-25
Context error.
- This service call was issued from a task.
- This service call was issued in the CPU locked state.
- This service call was issued in the dispatching disabled state.
E_NOEXS
-42
Non-existent object.
- Specified fixed-sized memory pool is not registered.
E_RLWAI
-49
Forced release from the WAITING state.
- Accept rel_wai/irel_wai while waiting.