From a274ac15ed069bae4118e3251359240379b6801b Mon Sep 17 00:00:00 2001 From: Henrik Rydberg Date: Wed, 29 Aug 2012 20:48:02 +0200 Subject: [PATCH] Input: evdev - Add the events() callback By sending a full frame of events at the same time, the irqsoff latency at heavy load is brought down from 200 us to 100 us. Cc: Daniel Kurtz Tested-by: Benjamin Tissoires Tested-by: Ping Cheng Acked-by: Dmitry Torokhov Signed-off-by: Henrik Rydberg --- drivers/input/evdev.c | 94 +++++++++++++++++++++++++++---------------- 1 file changed, 60 insertions(+), 34 deletions(-) diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c index a0692c551be5..118d0300f1fb 100644 --- a/drivers/input/evdev.c +++ b/drivers/input/evdev.c @@ -54,16 +54,9 @@ struct evdev_client { static struct evdev *evdev_table[EVDEV_MINORS]; static DEFINE_MUTEX(evdev_table_mutex); -static void evdev_pass_event(struct evdev_client *client, - struct input_event *event, - ktime_t mono, ktime_t real) +static void __pass_event(struct evdev_client *client, + const struct input_event *event) { - event->time = ktime_to_timeval(client->clkid == CLOCK_MONOTONIC ? - mono : real); - - /* Interrupts are disabled, just acquire the lock. */ - spin_lock(&client->buffer_lock); - client->buffer[client->head++] = *event; client->head &= client->bufsize - 1; @@ -86,8 +79,63 @@ static void evdev_pass_event(struct evdev_client *client, client->packet_head = client->head; kill_fasync(&client->fasync, SIGIO, POLL_IN); } +} + +static void evdev_pass_values(struct evdev_client *client, + const struct input_value *vals, unsigned int count, + ktime_t mono, ktime_t real) +{ + struct evdev *evdev = client->evdev; + const struct input_value *v; + struct input_event event; + bool wakeup = false; + + event.time = ktime_to_timeval(client->clkid == CLOCK_MONOTONIC ? + mono : real); + + /* Interrupts are disabled, just acquire the lock. */ + spin_lock(&client->buffer_lock); + + for (v = vals; v != vals + count; v++) { + event.type = v->type; + event.code = v->code; + event.value = v->value; + __pass_event(client, &event); + if (v->type == EV_SYN && v->code == SYN_REPORT) + wakeup = true; + } spin_unlock(&client->buffer_lock); + + if (wakeup) + wake_up_interruptible(&evdev->wait); +} + +/* + * Pass incoming events to all connected clients. + */ +static void evdev_events(struct input_handle *handle, + const struct input_value *vals, unsigned int count) +{ + struct evdev *evdev = handle->private; + struct evdev_client *client; + ktime_t time_mono, time_real; + + time_mono = ktime_get(); + time_real = ktime_sub(time_mono, ktime_get_monotonic_offset()); + + rcu_read_lock(); + + client = rcu_dereference(evdev->grab); + + if (client) + evdev_pass_values(client, vals, count, time_mono, time_real); + else + list_for_each_entry_rcu(client, &evdev->client_list, node) + evdev_pass_values(client, vals, count, + time_mono, time_real); + + rcu_read_unlock(); } /* @@ -96,32 +144,9 @@ static void evdev_pass_event(struct evdev_client *client, static void evdev_event(struct input_handle *handle, unsigned int type, unsigned int code, int value) { - struct evdev *evdev = handle->private; - struct evdev_client *client; - struct input_event event; - ktime_t time_mono, time_real; + struct input_value vals[] = { { type, code, value } }; - time_mono = ktime_get(); - time_real = ktime_sub(time_mono, ktime_get_monotonic_offset()); - - event.type = type; - event.code = code; - event.value = value; - - rcu_read_lock(); - - client = rcu_dereference(evdev->grab); - - if (client) - evdev_pass_event(client, &event, time_mono, time_real); - else - list_for_each_entry_rcu(client, &evdev->client_list, node) - evdev_pass_event(client, &event, time_mono, time_real); - - rcu_read_unlock(); - - if (type == EV_SYN && code == SYN_REPORT) - wake_up_interruptible(&evdev->wait); + evdev_events(handle, vals, 1); } static int evdev_fasync(int fd, struct file *file, int on) @@ -1050,6 +1075,7 @@ MODULE_DEVICE_TABLE(input, evdev_ids); static struct input_handler evdev_handler = { .event = evdev_event, + .events = evdev_events, .connect = evdev_connect, .disconnect = evdev_disconnect, .fops = &evdev_fops,