[PATCH 1/1] Drivers: hv: vmbus: Use get_cpu() to get the current CPU

From: K. Y. Srinivasan
Date: Mon Dec 15 2014 - 01:24:29 EST


Replace calls for smp_processor_id() to get_cpu() to get the CPU ID of
the current CPU. In these instances, there is no correctness issue with
regards to preemption, we just need the current CPU ID.

Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx>
---
drivers/hv/channel_mgmt.c | 4 +++-
drivers/hv/connection.c | 6 ++++--
2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index d36ce68..a205246 100644
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -813,7 +813,7 @@ cleanup:
struct vmbus_channel *vmbus_get_outgoing_channel(struct vmbus_channel *primary)
{
struct list_head *cur, *tmp;
- int cur_cpu = hv_context.vp_index[smp_processor_id()];
+ int cur_cpu;
struct vmbus_channel *cur_channel;
struct vmbus_channel *outgoing_channel = primary;
int cpu_distance, new_cpu_distance;
@@ -821,6 +821,8 @@ struct vmbus_channel *vmbus_get_outgoing_channel(struct vmbus_channel *primary)
if (list_empty(&primary->sc_list))
return outgoing_channel;

+ cur_cpu = hv_context.vp_index[get_cpu()];
+ put_cpu();
list_for_each_safe(cur, tmp, &primary->sc_list) {
cur_channel = list_entry(cur, struct vmbus_channel, sc_list);
if (cur_channel->state != CHANNEL_OPENED_STATE)
diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index e206619..a63a795 100644
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -80,8 +80,10 @@ static int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo,
msg->interrupt_page = virt_to_phys(vmbus_connection.int_page);
msg->monitor_page1 = virt_to_phys(vmbus_connection.monitor_pages[0]);
msg->monitor_page2 = virt_to_phys(vmbus_connection.monitor_pages[1]);
- if (version == VERSION_WIN8_1)
- msg->target_vcpu = hv_context.vp_index[smp_processor_id()];
+ if (version == VERSION_WIN8_1) {
+ msg->target_vcpu = hv_context.vp_index[get_cpu()];
+ put_cpu();
+ }

/*
* Add to list before we send the request since we may
--
1.7.4.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/