Hi
I am having an issue with the RinBuf library - I am accepting packets from SPI, buffering them in a ringbuf until I can send onwards via BLE. The specific issue I am having is that calling nrf_ringbuf_free does not actually free bytes in the ringbuf!
NRF_RINGBUF_DEF(m_RingBufBleNormalPriority, 2048);
#define MESSAGE_PLUS_PAYLOAD_BYTES 244
void foo(void)
{
nrf_ringbuf_init(&m_RingBufBleNormalPriority);
ret_code_t err_code = NRF_SUCCESS;
uint8_t * p_buffer;
uint32_t BufferLength = 0;
uint32_t a;
//do this 8 times = 8*244 bytes = 1952 bytes used
for (a=0; a<8; a++)
{
BufferLength = MESSAGE_PLUS_PAYLOAD_BYTES;
err_code = nrf_ringbuf_alloc(&m_RingBufBleNormalPriority, &p_buffer, &BufferLength, true);
if (err_code != NRF_SUCCESS)
{
NRF_LOG_INFO("Error - nrf_ringbuf_alloc err: %d",err_code);
return;
}
if (BufferLength != MESSAGE_PLUS_PAYLOAD_BYTES)
{
NRF_LOG_INFO("Error - Wrong length allocated");
nrf_ringbuf_put(&m_RingBufBleNormalPriority, 0);
return;
}
//would ordinarily fill the buffer with data from SPI here
nrf_ringbuf_put(&m_RingBufBleNormalPriority, MESSAGE_PLUS_PAYLOAD_BYTES);
}
//At this point, 1952 bytes out of the total 2028 bytes utilised in the ring buffer
//Get one record == 244 bytes from Ring Buffer
BufferLength = MESSAGE_PLUS_PAYLOAD_BYTES;
err_code = nrf_ringbuf_get(&m_RingBufBleNormalPriority, &p_buffer, &BufferLength, true);
if (err_code != NRF_SUCCESS)
{
NRF_LOG_INFO("Error - nrf_ringbuf_get err: %d",err_code);
return;
}
if (BufferLength != MESSAGE_PLUS_PAYLOAD_BYTES)
{
NRF_LOG_INFO("Error - Wrong length read from buffer");
nrf_ringbuf_free(&m_RingBufBleNormalPriority, 0);
return;
}
nrf_ringbuf_free(&m_RingBufBleNormalPriority, MESSAGE_PLUS_PAYLOAD_BYTES);
//At this point, buffer utilisation is 1952-244 bytes = 1708 with 340 bytes remaining
//Add another 244 bytes to the Ring Buffer (should be space)
BufferLength = MESSAGE_PLUS_PAYLOAD_BYTES;
err_code = nrf_ringbuf_alloc(&m_RingBufBleNormalPriority, &p_buffer, &BufferLength, true);
if (err_code != NRF_SUCCESS || BufferLength != MESSAGE_PLUS_PAYLOAD_BYTES)
{
NRF_LOG_INFO("Error - nrf_ringbuf_alloc err: %d",err_code);
NRF_LOG_INFO("Requested: %d | Allocated: %d",MESSAGE_PLUS_PAYLOAD_BYTES,BufferLength);
nrf_ringbuf_put(&m_RingBufBleNormalPriority, 0);
return;
/*************** THIS FAILS HERE ***************/
//BufferLength != MESSAGE_PLUS_PAYLOAD_BYTES only 60 bytes have been allocated
//there are 340 available
//If I do another GET operation then I get the same result, 60 bytes available!
//The function nrf_ringbuf_free DOES NOT free up the 244 bytes I have asked it to!!
}
nrf_ringbuf_put(&m_RingBufBleNormalPriority, MESSAGE_PLUS_PAYLOAD_BYTES);
}
nrf_ringbuf_put(&m_RingBufBleNormalPriority, 0);
See the comments in the example above. I put and commit 244 bytes into the run buffer 8 times over, I then get and free 244 bytes, leaving 340 available
I then attempt to put another 244 bytes into the ring buffer, but I am only given an allocation of 60 bytes despite there being 340 bytes available. The example is monolithic so I am not checking for NRF_ERROR_BUSY (although I do in my real app), neither am I doing anything with the allocated buffers in the above. Incidentally, the initial 8x244 bytes is 1952, 2048-1952 is 60 . Sixty is what I am being offered in my final request DESPITE having Gotten and Free'd 244 bytes beforehand. The nrf_ringbuf_free returns NRF_SUCCESS. If I entend the size of the ringbuff then it just delays the issue, eventually it fills despite having been freed.
Any idea's - maybe I just cannot use a ringbuff in this manner?
Nigel
