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.
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.
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
The fixed-sized memory pool is reset as a result of issuing vrst_mpf.
EV_RST
Forced release from waiting (accept del_mpf while waiting).
E_DLT

Note 1 Invoking tasks are queued to the target fixed-size memory pool wait queue in the order defined at creating the fixed-sized memory pool. (FIFO order or current priority order).
Note 2 The contents of the block are undefined.
Note 3 The alignment number of memory block is 1. Please perform the following, in order to enlarge the alignment number of memory blocks.
- Specify the memory block size to a multiple of the desired alignment number at creating the fixed-sized memory pool.
- Make the start address of the fixed-sized memory pool area into the address of the desired alignment number.
Return value
Macro
Value
Description
E_OK
0
Normal completion.
E_PAR
-17
Parameter error.
- p_blk == NULL
E_ID
-18
Invalid ID number.
- mpfid < 0
- mpfid > VTMAX_MPF
E_CTX
-25
Context error.
- This service call was issued from a non-task.
- This service call was issued in the CPU locked state.
- This service call was issued in the dispatching disabled state.
- This service call was issued in the status "PSW.IPL > kernel interrupt mask level".
E_MACV
-26
Memory access violation.
- Stack pointer points out of user stack for invoking task.
- The operand-write access to the area indicated by p_blk has not been permitted to the invoking task.
E_NOEXS
-42
Non-existent object.
- The fixed-sized memory pool specified by mpfid does not exist.
E_RLWAI
-49
Forced release from the WAITING state.
- Accept rel_wai/irel_wai while waiting.
E_DLT
-51
Waiting object deleted.
- Accept del_mpf while waiting.
EV_RST
-127
Released from WAITING state by the object reset (vrst_mpf)