diff options
| author | Peter Hurley <peter@hurleysoftware.com> | 2013-06-15 17:36:08 +0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-07-24 03:47:08 +0400 |
| commit | 7bfe0b7116be207cf2204ae06335cc89d8f8ee02 (patch) | |
| tree | 03175cd2ce9dd8013c4aaa8e2dd426767aa1a4c7 /drivers/tty/pty.c | |
| parent | 7391ee16950e772076d321792d9fbf030f921345 (diff) | |
| download | linux-7bfe0b7116be207cf2204ae06335cc89d8f8ee02.tar.xz | |
tty: Track flip buffer memory limit atomically
Lockless flip buffers require atomically updating the bytes-in-use
watermark.
The pty driver also peeks at the watermark value to limit
memory consumption to a much lower value than the default; query
the watermark with new fn, tty_buffer_space_avail().
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/pty.c')
| -rw-r--r-- | drivers/tty/pty.c | 10 |
1 files changed, 3 insertions, 7 deletions
diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c index 1b39dd639ee9..b38a28bd9511 100644 --- a/drivers/tty/pty.c +++ b/drivers/tty/pty.c @@ -89,17 +89,13 @@ static void pty_unthrottle(struct tty_struct *tty) * pty_space - report space left for writing * @to: tty we are writing into * - * The tty buffers allow 64K but we sneak a peak and clip at 8K this - * allows a lot of overspill room for echo and other fun messes to - * be handled properly + * Limit the buffer space used by ptys to 8k. */ static int pty_space(struct tty_struct *to) { - int n = 8192 - to->port->buf.memory_used; - if (n < 0) - return 0; - return n; + int n = tty_buffer_space_avail(to->port); + return min(n, 8192); } /** |