k_fifo_alloc_put vs k_malloc in FIFO?

[AndrewLivesChaos]

A simple question: what's the difference between the use of k_malloc with the FIFO's API, like (found in threads Zephyr's example)

typedef struct
{
    void *fifo_reserved;
    uint8_t data1[ 6 ];
    uint8_t data2[ 256 ];
    uint16_t data3;

} fifo_item_t;


void producer_thread(void)
{
    for ( ;; )
    {
        fifo_item_t *fifoItem = k_malloc( sizeof( fifo_item_t ) );

        //[ process fifo item... ]

        k_fifo_put( &fifo, fifoItem );

        //[ do other stuff... ]
    }
}


void consumer_thread(void)
{
    fifo_item_t *fifoItem;

    for ( ;; )
    {
        fifoItem = k_fifo_get( &fifo, K_FOREVER );
        
        //[ process fifo item... ]

        k_free( fifoItem );
    }
}

, and the use of the API k_fifo_alloc_put ? The documentation about it is not clear for me.