On Wed, Jan 07, 2015 at 10:56:03AM -0800, Anshul Garg wrote:
> From: Anshul Garg <aksgarg1989@xxxxxxxxx>
>
> Since the client clk_type is changed , flush pending
> events from client buffer and queue SYN_DROPPED event.
> Added check for duplicate clk_type change request.
>
> Signed-off-by: Anshul Garg <anshul.g@xxxxxxxxxxx>
> ---
> drivers/input/evdev.c | 58 ++++++++++++++++++++++++++++++-------------------
> 1 file changed, 36 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
> index b1a52ab..223367e 100644
> --- a/drivers/input/evdev.c
> +++ b/drivers/input/evdev.c
> @@ -62,27 +62,6 @@ struct evdev_client {
> struct input_event buffer[];
> };
>
> -static int evdev_set_clk_type(struct evdev_client *client, unsigned int clkid)
> -{
> - switch (clkid) {
> -
> - case CLOCK_REALTIME:
> - client->clk_type = EV_CLK_REAL;
> - break;
> - case CLOCK_MONOTONIC:
> - client->clk_type = EV_CLK_MONO;
> - break;
> - case CLOCK_BOOTTIME:
> - client->clk_type = EV_CLK_BOOT;
> - break;
> - default:
> - return -EINVAL;
> - }
> -
> - return 0;
> -}
> -
> -/* flush queued events of type @type, caller must hold client->buffer_lock */
> static void __evdev_flush_queue(struct evdev_client *client, unsigned int type)
> {
> unsigned int i, head, num;
> @@ -160,6 +139,41 @@ static void evdev_queue_syn_dropped(struct evdev_client *client)
> spin_unlock_irqrestore(&client->buffer_lock, flags);
> }
>
> +static int evdev_set_clk_type(struct evdev_client *client,
> + struct input_dev *dev, unsigned int clkid)
> +{
> + if (client->clk_type == clkid)
> + return 0;
> +
> + switch (clkid) {
> +
> + case CLOCK_REALTIME:
> + client->clk_type = EV_CLK_REAL;
> + break;
> + case CLOCK_MONOTONIC:
> + client->clk_type = EV_CLK_MONO;
> + break;
> + case CLOCK_BOOTTIME:
> + client->clk_type = EV_CLK_BOOT;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + spin_lock_irq(&dev->event_lock);
> + spin_lock(&client->buffer_lock);
> + spin_unlock(&dev->event_lock);
Umm, why?
> +
> + /* Flush clients events after clk_type is changed
> + * and queue SYN_DROPPED event.*/
> + client->packet_head = client->head = client->tail;
> + spin_unlock_irq(&client->buffer_lock);
> +
> + evdev_queue_syn_dropped(client);
This is still racy. I'd rather we passed a flag to
evdev_queue_syn_dropped() to indicate it should also clear queue.
Thanks.
--
Dmitry
--
To unsubscribe from this list: send the line "unsubscribe linux-input" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
