From: Milton Miller <miltonm@bga.com>
Have the hvc console code try to pull characters immediately when receiving an
interrupt, and kick the poll thread only if the immediate poll indicates it
needed a call back to do more work.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
drivers/char/hvc_console.c | 10 +++++++---
1 files changed, 7 insertions(+), 3 deletions(-)
diff -puN drivers/char/hvc_console.c~hvc_console-dont-always-kick-the-poll-thread-in-interrupt drivers/char/hvc_console.c
--- 25/drivers/char/hvc_console.c~hvc_console-dont-always-kick-the-poll-thread-in-interrupt Wed Jul 6 14:00:23 2005
+++ 25-akpm/drivers/char/hvc_console.c Wed Jul 6 14:00:23 2005
@@ -254,13 +254,17 @@ static void hvc_kick(void)
wake_up_process(hvc_task);
}
+static int hvc_poll(struct hvc_struct *hp);
+
/*
* NOTE: This API isn't used if the console adapter doesn't support interrupts.
* In this case the console is poll driven.
*/
static irqreturn_t hvc_handle_interrupt(int irq, void *dev_instance, struct pt_regs *regs)
{
- hvc_kick();
+ /* if hvc_poll request a repoll, then kick the hvcd thread */
+ if (hvc_poll(dev_instance))
+ hvc_kick();
return IRQ_HANDLED;
}
@@ -598,8 +602,8 @@ static int hvc_poll(struct hvc_struct *h
/*
* Account for the total amount read in one loop, and if above
- * 64 bytes, we do a quick schedule loop to let the tty grok the
- * data and eventually throttle us.
+ * 64 bytes, we do a quick schedule loop to let the tty grok
+ * the data and eventually throttle us.
*/
read_total += n;
if (read_total >= 64) {
_