diff --git a/sys/dev/vt/vt_buf.c b/sys/dev/vt/vt_buf.c index 9b65a7cb889..ec08967232f 100644 --- a/sys/dev/vt/vt_buf.c +++ b/sys/dev/vt/vt_buf.c @@ -45,6 +45,7 @@ static MALLOC_DEFINE(M_VTBUF, "vtbuf", "vt buffer"); #define VTBUF_LOCK(vb) mtx_lock_spin(&(vb)->vb_lock) #define VTBUF_UNLOCK(vb) mtx_unlock_spin(&(vb)->vb_lock) +#define VTBUF_LOCK_OWNED(vb) mtx_owned(&(vb)->vb_lock) #define POS_INDEX(c, r) (((r) << 12) + (c)) #define POS_COPY(d, s) do { \ @@ -740,9 +741,19 @@ vtbuf_flush_mark(struct vt_buf *vb) area.tr_end.tp_col = vb->vb_scr_size.tp_col; area.tr_end.tp_row = MAX(s, e) + 1; - VTBUF_LOCK(vb); - vtbuf_dirty(vb, &area); - VTBUF_UNLOCK(vb); + /* + * If the request originates from a keyboard, the vtbuf is + * locked by teken for the entire duration of the request. + * For all other sources, we avoid holding the spinlock for + * extended periods. + */ + if (VTBUF_LOCK_OWNED(vb)) { + vtbuf_dirty(vb, &area); + } else { + VTBUF_LOCK(vb); + vtbuf_dirty(vb, &area); + VTBUF_UNLOCK(vb); + } } }