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Date: Wed, 19 Feb 2020 09:41:01 +0100 From: Jiri Slaby <jslaby@...e.cz> To: gregkh@...uxfoundation.org Cc: linux-serial@...r.kernel.org, linux-kernel@...r.kernel.org, Jiri Slaby <jslaby@...e.cz> Subject: [PATCH 07/24] n_hdlc: simplify freeing of buffer list n_hdlc_release contains four loops to free each buffer list. Create a helper (n_hdlc_free_buf_list) and call it for every list instead. It makes n_hdlc_release more readable. We are switching from "for (;;)" to "do {} while (buf)" which avoids the "if (buf)" completely -- kfree is a nop for NULL pointers. Signed-off-by: Jiri Slaby <jslaby@...e.cz> --- drivers/tty/n_hdlc.c | 45 ++++++++++++++------------------------------ 1 file changed, 14 insertions(+), 31 deletions(-) diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c index a713a98fea2e..07ba42badd7a 100644 --- a/drivers/tty/n_hdlc.c +++ b/drivers/tty/n_hdlc.c @@ -215,6 +215,16 @@ static struct tty_ldisc_ops n_hdlc_ldisc = { .flush_buffer = flush_rx_queue, }; +static void n_hdlc_free_buf_list(struct n_hdlc_buf_list *list) +{ + struct n_hdlc_buf *buf; + + do { + buf = n_hdlc_buf_get(list); + kfree(buf); + } while (buf); +} + /** * n_hdlc_release - release an n_hdlc per device line discipline info structure * @n_hdlc - per device line discipline info structure @@ -222,7 +232,6 @@ static struct tty_ldisc_ops n_hdlc_ldisc = { static void n_hdlc_release(struct n_hdlc *n_hdlc) { struct tty_struct *tty = n_hdlc2tty (n_hdlc); - struct n_hdlc_buf *buf; /* Ensure that the n_hdlcd process is not hanging on select()/poll() */ wake_up_interruptible (&tty->read_wait); @@ -231,37 +240,11 @@ static void n_hdlc_release(struct n_hdlc *n_hdlc) if (tty->disc_data == n_hdlc) tty->disc_data = NULL; /* Break the tty->n_hdlc link */ - /* Release transmit and receive buffers */ - for(;;) { - buf = n_hdlc_buf_get(&n_hdlc->rx_free_buf_list); - if (buf) { - kfree(buf); - } else - break; - } - for(;;) { - buf = n_hdlc_buf_get(&n_hdlc->tx_free_buf_list); - if (buf) { - kfree(buf); - } else - break; - } - for(;;) { - buf = n_hdlc_buf_get(&n_hdlc->rx_buf_list); - if (buf) { - kfree(buf); - } else - break; - } - for(;;) { - buf = n_hdlc_buf_get(&n_hdlc->tx_buf_list); - if (buf) { - kfree(buf); - } else - break; - } + n_hdlc_free_buf_list(&n_hdlc->rx_free_buf_list); + n_hdlc_free_buf_list(&n_hdlc->tx_free_buf_list); + n_hdlc_free_buf_list(&n_hdlc->rx_buf_list); + n_hdlc_free_buf_list(&n_hdlc->tx_buf_list); kfree(n_hdlc); - } /* end of n_hdlc_release() */ /** -- 2.25.0
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