From 132368bd0b286457f83f56d0bbdecd85999562dc Mon Sep 17 00:00:00 2001 From: "K. Y. Srinivasan" Date: Sat, 1 Dec 2012 06:46:33 -0800 Subject: Drivers: hv: Add state to manage batched reading For the "read" side signaling optimization, the reader has to completely drain the queue before exiting. Add state to manage this "batched" reading. Signed-off-by: K. Y. Srinivasan Reviewed-by: Haiyang Zhang Signed-off-by: Greg Kroah-Hartman --- drivers/hv/channel_mgmt.c | 7 +++++++ include/linux/hyperv.h | 20 ++++++++++++++++++++ 2 files changed, 27 insertions(+) diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index 2f84c5cff8d4..7bf59177aaf8 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -275,6 +275,13 @@ static void vmbus_onoffer(struct vmbus_channel_message_header *hdr) return; } + /* + * By default we setup state to enable batched + * reading. A specific service can choose to + * disable this prior to opening the channel. + */ + newchannel->batched_reading = true; + memcpy(&newchannel->offermsg, offer, sizeof(struct vmbus_channel_offer_channel)); newchannel->monitor_grp = (u8)offer->monitorid / 32; diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index e73b852156b1..1ffe84de6c55 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -882,8 +882,28 @@ struct vmbus_channel { void (*onchannel_callback)(void *context); void *channel_callback_context; + + /* + * A channel can be marked for efficient (batched) + * reading: + * If batched_reading is set to "true", we read until the + * channel is empty and hold off interrupts from the host + * during the entire read process. + * If batched_reading is set to "false", the client is not + * going to perform batched reading. + * + * By default we will enable batched reading; specific + * drivers that don't want this behavior can turn it off. + */ + + bool batched_reading; }; +static inline void set_channel_read_state(struct vmbus_channel *c, bool state) +{ + c->batched_reading = state; +} + void vmbus_onmessage(void *context); int vmbus_request_offers(void); -- cgit v1.2.3