kernel_optimize_test/include/linux/tty_flip.h
Paul Fulghum 8977d929e4 [PATCH] tty buffering stall fix
Prevent stalled processing of received data when a driver allocates tty
buffer space but does not immediately follow the allocation with more data
and a call to schedule receive tty processing.  (example: hvc_console) This
bug was introduced by the first locking patch for the new tty buffering.

Signed-off-by: Paul Fulghum <paulkf@microgate.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-10 08:13:12 -08:00

51 lines
1.3 KiB
C

#ifndef _LINUX_TTY_FLIP_H
#define _LINUX_TTY_FLIP_H
extern int tty_buffer_request_room(struct tty_struct *tty, size_t size);
extern int tty_insert_flip_string(struct tty_struct *tty, unsigned char *chars, size_t size);
extern int tty_insert_flip_string_flags(struct tty_struct *tty, unsigned char *chars, char *flags, size_t size);
extern int tty_prepare_flip_string(struct tty_struct *tty, unsigned char **chars, size_t size);
extern int tty_prepare_flip_string_flags(struct tty_struct *tty, unsigned char **chars, char **flags, size_t size);
#ifdef INCLUDE_INLINE_FUNCS
#define _INLINE_ extern
#else
#define _INLINE_ static __inline__
#endif
_INLINE_ int tty_insert_flip_char(struct tty_struct *tty,
unsigned char ch, char flag)
{
struct tty_buffer *tb = tty->buf.tail;
if (tb && tb->active && tb->used < tb->size) {
tb->flag_buf_ptr[tb->used] = flag;
tb->char_buf_ptr[tb->used++] = ch;
return 1;
}
return tty_insert_flip_string_flags(tty, &ch, &flag, 1);
}
_INLINE_ void tty_schedule_flip(struct tty_struct *tty)
{
unsigned long flags;
spin_lock_irqsave(&tty->buf.lock, flags);
if (tty->buf.tail != NULL) {
tty->buf.tail->active = 0;
tty->buf.tail->commit = tty->buf.tail->used;
}
spin_unlock_irqrestore(&tty->buf.lock, flags);
schedule_delayed_work(&tty->buf.work, 1);
}
#undef _INLINE_
#endif /* _LINUX_TTY_FLIP_H */