Everything

tget_mpl

Outline
Acquire variable-sized memory block (with timeout).
C format
 ER      tget_mpl (ID mplid, UINT blksz, VP *p_blk, TMO tmout);
Parameter(s)
I/O
Parameter
Description
I
 ID      mplid;
ID number of the variable-sized memory pool from which a memory block is acquired.
I
 UINT    blksz;
Memory block size to be acquired (in bytes).
O
 VP      *p_blk;
Start address of the acquired memory block.
I
 TMO     tmout;
Specified timeout (unit:millisecond).
TMO_FEVR: Waiting forever.
TMO_POL: Polling.
Value: Specified timeout.

Explanation
This service call acquires a variable-size memory block of the size specified by parameter blksz from the variable-size memory pool specified by parameter mplid, and stores its start address into the area specified by parameter p_blk.
If no variable-size memory blocks could be acquired from the target variable-size memory pool (no successive areas equivalent to the requested size were available) when this service call is issued, this service call does not acquire variable-size memory blocks but queues the invoking task to the target variable-size memory pool wait queue and moves it from the RUNNING state to the WAITING state with timeout (variable-size memory block acquisition wait state).
The WAITING state for a variable-sized memory block is cancelled in the following cases, and then moved to the READY state.
WAITING State for a Variable-sized Memory Block Cancel Operation
Return Value
The variable-size memory block that satisfies the requested size was returned to the target variable-size memory pool as a result of issuing rel_mpl.
E_OK
The variable-size memory block that satisfies the requested size was returned to the target variable-size memory pool as a result of issuing irel_mpl.
E_OK
Forced release from waiting (accept rel_wai while waiting).
E_RLWAI
Forced release from waiting (accept irel_wai while waiting).
E_RLWAI
Polling failure or timeout.
E_TMOUT

Note 1 The RI850V4 acquires variable-size memory blocks in the unit of "integral multiple of 4". If a value other than an integral multiple of 4 is specified for parameter blksz, it is rounded up to be an integral multiple of 4.
Note 2 Invoking tasks are queued to the target variable-size memory pool wait queue in the order defined during configuration (FIFO order or priority order).
Note 3 If the variable-size memory block acquisition wait state is cancelled because rel_wai or irel_wai was issued or the wait time elapsed, the contents in the area specified by parameter p_blk become undefined.
Note 4 TMO_FEVR is specified for wait time tmout, processing equivalent to get_mpl will be executed. When TMO_POL is specified, processing equivalent to pget_mpl /ipget_mpl will be executed.
Return value
Macro
Value
Description
E_OK
0
Normal completion.
E_PAR
-17
Parameter error.
- blksz = 0x0
- blksz > 0x7fffffff
- tmout < TMO_FEVR
E_ID
-18
Invalid ID number.
- mplid < 0x0
- mplid > Maximum ID number
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.
E_NOEXS
-42
Non-existent object.
- Specified variable-sized memory pool is not registered.
E_RLWAI
-49
Forced release from the WAITING state.
- Accept rel_wai/irel_wai while waiting.
E_TMOUT
-50
Timeout.
- Polling failure or timeout.