uart_tx_lock       42 kernel/uart.c  struct spinlock uart_tx_lock;
uart_tx_lock       77 kernel/uart.c    initlock(&uart_tx_lock, "uart");
uart_tx_lock       89 kernel/uart.c    acquire(&uart_tx_lock);
uart_tx_lock       98 kernel/uart.c      sleep(&uart_tx_r, &uart_tx_lock);
uart_tx_lock      103 kernel/uart.c    release(&uart_tx_lock);
uart_tx_lock      188 kernel/uart.c    acquire(&uart_tx_lock);
uart_tx_lock      190 kernel/uart.c    release(&uart_tx_lock);