Messages in this thread Patch in this message | | | From | Alan Cox <> | Subject | [PATCH 52/80] vt: remove bogus lock dropping | Date | Mon, 13 Oct 2008 10:41:16 +0100 |
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From: Alan Cox <alan@redhat.com>
For hysterical raisins the vt layer drops and retakes locks in the write method. This is a left over from the days when user/kernel data was passed directly to the tty not pre-buffered.
Signed-off-by: Alan Cox <alan@redhat.com> ---
drivers/char/vt.c | 18 ------------------ 1 files changed, 0 insertions(+), 18 deletions(-)
diff --git a/drivers/char/vt.c b/drivers/char/vt.c index 05ca1c5..ec94521 100644 --- a/drivers/char/vt.c +++ b/drivers/char/vt.c @@ -2136,27 +2136,9 @@ static int do_con_write(struct tty_struct *tty, const unsigned char *buf, int co release_console_sem(); return 0; } - release_console_sem(); - orig_buf = buf; orig_count = count; - /* At this point 'buf' is guaranteed to be a kernel buffer - * and therefore no access to userspace (and therefore sleeping) - * will be needed. The con_buf_mtx serializes all tty based - * console rendering and vcs write/read operations. We hold - * the console spinlock during the entire write. - */ - - acquire_console_sem(); - - vc = tty->driver_data; - if (vc == NULL) { - printk(KERN_ERR "vt: argh, driver_data _became_ NULL !\n"); - release_console_sem(); - goto out; - } - himask = vc->vc_hi_font_mask; charmask = himask ? 0x1ff : 0xff;
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