summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorK. Y. Srinivasan <kys@microsoft.com>2012-12-01 15:46:33 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-01-17 19:46:39 +0100
commit132368bd0b286457f83f56d0bbdecd85999562dc (patch)
treee16a4f6130d475d1f44270c088e446306b3e8355
parentDrivers: hv: Implement routines for read side signaling optimization (diff)
downloadlinux-132368bd0b286457f83f56d0bbdecd85999562dc.tar.xz
linux-132368bd0b286457f83f56d0bbdecd85999562dc.zip
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 <kys@microsoft.com> Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/hv/channel_mgmt.c7
-rw-r--r--include/linux/hyperv.h20
2 files changed, 27 insertions, 0 deletions
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);