Drivers: hv: vmbus: Remove the target_vp field from the vmbus_channel struct

The field is read only in __vmbus_open() and it is already stored twice
(after a call to hv_cpu_number_to_vp_number()) in target_cpu_store() and
init_vp_index(); there is no need to "cache" its value in the channel
data structure.

Suggested-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com>
Link: https://lore.kernel.org/r/20200617164642.37393-2-parri.andrea@gmail.com
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>

diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index 90070b3..8848d15 100644 (file)
--- a/drivers/hv/channel.c
+++ b/drivers/hv/channel.c
@@ -18,6 +18,7 @@
 #include <linux/uio.h>
 #include <linux/interrupt.h>
 #include <asm/page.h>
+#include <asm/mshyperv.h>
 
 #include "hyperv_vmbus.h"
 
@@ -176,7 +177,7 @@ static int __vmbus_open(struct vmbus_channel *newchannel,
        open_msg->child_relid = newchannel->offermsg.child_relid;
        open_msg->ringbuffer_gpadlhandle = newchannel->ringbuffer_gpadlhandle;
        open_msg->downstream_ringbuffer_pageoffset = newchannel->ringbuffer_send_offset;
-       open_msg->target_vp = newchannel->target_vp;
+       open_msg->target_vp = hv_cpu_number_to_vp_number(newchannel->target_cpu);
 
        if (userdatalen)
                memcpy(open_msg->userdata, userdata, userdatalen);

diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index 417a95e..278e392 100644 (file)
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -704,8 +704,6 @@ static void init_vp_index(struct vmbus_channel *channel)
                 */
                channel->numa_node = cpu_to_node(VMBUS_CONNECT_CPU);
                channel->target_cpu = VMBUS_CONNECT_CPU;
-               channel->target_vp =
-                       hv_cpu_number_to_vp_number(VMBUS_CONNECT_CPU);
                if (perf_chn)
                        hv_set_alloced_cpu(VMBUS_CONNECT_CPU);
                return;
@@ -739,7 +737,6 @@ static void init_vp_index(struct vmbus_channel *channel)
        cpumask_set_cpu(target_cpu, alloced_mask);
 
        channel->target_cpu = target_cpu;
-       channel->target_vp = hv_cpu_number_to_vp_number(target_cpu);
 
        free_cpumask_var(available_mask);
 }

diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 9147ee9..d2ddb46 100644 (file)
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -23,7 +23,6 @@
 #include <linux/cpu.h>
 #include <linux/sched/task_stack.h>
 
-#include <asm/mshyperv.h>
 #include <linux/delay.h>
 #include <linux/notifier.h>
 #include <linux/ptrace.h>
@@ -1779,7 +1778,6 @@ static ssize_t target_cpu_store(struct vmbus_channel *channel,
         */
 
        channel->target_cpu = target_cpu;
-       channel->target_vp = hv_cpu_number_to_vp_number(target_cpu);
        channel->numa_node = cpu_to_node(target_cpu);
 
        /* See init_vp_index(). */

diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 40df310..738efdb 100644 (file)
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -803,15 +803,14 @@ struct vmbus_channel {
        u64 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.
+        * Starting with win8, this field will be used to specify the
+        * target CPU 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 corresponding CPUID in the guest */
        u32 target_cpu;
        int numa_node;
        /*