Drivers: hv: Add state to manage incoming channel interrupt load
K. Y. Srinivasan [Sat, 1 Dec 2012 14:46:48 +0000 (06:46 -0800)]
Add state to bind a channel to a specific VCPU. This will help us better
distribute incoming interrupt load.

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>

drivers/hv/channel.c
drivers/hv/channel_mgmt.c
include/linux/hyperv.h

index 70a34da..9303252 100644 (file)
@@ -181,7 +181,7 @@ int vmbus_open(struct vmbus_channel *newchannel, u32 send_ringbuffer_size,
        open_msg->ringbuffer_gpadlhandle = newchannel->ringbuffer_gpadlhandle;
        open_msg->downstream_ringbuffer_pageoffset = send_ringbuffer_size >>
                                                  PAGE_SHIFT;
-       open_msg->server_contextarea_gpadlhandle = 0;
+       open_msg->target_vp = newchannel->target_vp;
 
        if (userdatalen > MAX_USER_DEFINED_BYTES) {
                err = -EINVAL;
index f4d9902..56ed45c 100644 (file)
@@ -302,6 +302,8 @@ static void vmbus_onoffer(struct vmbus_channel_message_header *hdr)
                                offer->connection_id;
        }
 
+       newchannel->target_vp = 0;
+
        memcpy(&newchannel->offermsg, offer,
               sizeof(struct vmbus_channel_offer_channel));
        newchannel->monitor_grp = (u8)offer->monitorid / 32;
index c6e2c44..8c3cb1f 100644 (file)
@@ -732,8 +732,15 @@ struct vmbus_channel_open_channel {
        /* GPADL for the channel's ring buffer. */
        u32 ringbuffer_gpadlhandle;
 
-       /* GPADL for the channel's server context save area. */
-       u32 server_contextarea_gpadlhandle;
+       /*
+        * Starting with win8, this field will be used to specify
+        * the target virtual processor on which to deliver the interrupt for
+        * the host to guest communication.
+        * Prior to win8, incoming channel interrupts would only
+        * be delivered on cpu 0. Setting this value to 0 would
+        * preserve the earlier behavior.
+        */
+       u32 target_vp;
 
        /*
        * The upstream ring buffer begins at offset zero in the memory
@@ -971,6 +978,16 @@ struct vmbus_channel {
        bool is_dedicated_interrupt;
        struct hv_input_signal_event_buffer sig_buf;
        struct hv_input_signal_event *sig_event;
+
+       /*
+        * Starting with win8, this field will be used to specify
+        * the target virtual processor on which to deliver the interrupt for
+        * the host to guest communication.
+        * Prior to win8, incoming channel interrupts would only
+        * be delivered on cpu 0. Setting this value to 0 would
+        * preserve the earlier behavior.
+        */
+       u32 target_vp;
 };
 
 static inline void set_channel_read_state(struct vmbus_channel *c, bool state)