vmbus: remove conditional locking of vmbus_write

All current usage of vmbus write uses the acquire_lock flag, therefore
having it be optional is unnecessary. This also fixes a sparse warning
since sparse doesn't like when a function has conditional locking.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index 18cc1c7..81a80c8 100644 (file)
--- a/drivers/hv/channel.c
+++ b/drivers/hv/channel.c
@@ -651,7 +651,6 @@ int vmbus_sendpacket_ctl(struct vmbus_channel *channel, void *buffer,
        u32 packetlen_aligned = ALIGN(packetlen, sizeof(u64));
        struct kvec bufferlist[3];
        u64 aligned_data = 0;
-       bool lock = channel->acquire_ring_lock;
        int num_vecs = ((bufferlen != 0) ? 3 : 1);
 
 
@@ -670,7 +669,7 @@ int vmbus_sendpacket_ctl(struct vmbus_channel *channel, void *buffer,
        bufferlist[2].iov_base = &aligned_data;
        bufferlist[2].iov_len = (packetlen_aligned - packetlen);
 
-       return hv_ringbuffer_write(channel, bufferlist, num_vecs, lock);
+       return hv_ringbuffer_write(channel, bufferlist, num_vecs);
 }
 EXPORT_SYMBOL(vmbus_sendpacket_ctl);
 
@@ -716,12 +715,10 @@ int vmbus_sendpacket_pagebuffer_ctl(struct vmbus_channel *channel,
        u32 packetlen_aligned;
        struct kvec bufferlist[3];
        u64 aligned_data = 0;
-       bool lock = channel->acquire_ring_lock;
 
        if (pagecount > MAX_PAGE_BUFFER_COUNT)
                return -EINVAL;
 
-
        /*
         * Adjust the size down since vmbus_channel_packet_page_buffer is the
         * largest size we support
@@ -753,7 +750,7 @@ int vmbus_sendpacket_pagebuffer_ctl(struct vmbus_channel *channel,
        bufferlist[2].iov_base = &aligned_data;
        bufferlist[2].iov_len = (packetlen_aligned - packetlen);
 
-       return hv_ringbuffer_write(channel, bufferlist, 3, lock);
+       return hv_ringbuffer_write(channel, bufferlist, 3);
 }
 EXPORT_SYMBOL_GPL(vmbus_sendpacket_pagebuffer_ctl);
 
@@ -789,7 +786,6 @@ int vmbus_sendpacket_mpb_desc(struct vmbus_channel *channel,
        u32 packetlen_aligned;
        struct kvec bufferlist[3];
        u64 aligned_data = 0;
-       bool lock = channel->acquire_ring_lock;
 
        packetlen = desc_size + bufferlen;
        packetlen_aligned = ALIGN(packetlen, sizeof(u64));
@@ -809,7 +805,7 @@ int vmbus_sendpacket_mpb_desc(struct vmbus_channel *channel,
        bufferlist[2].iov_base = &aligned_data;
        bufferlist[2].iov_len = (packetlen_aligned - packetlen);
 
-       return hv_ringbuffer_write(channel, bufferlist, 3, lock);
+       return hv_ringbuffer_write(channel, bufferlist, 3);
 }
 EXPORT_SYMBOL_GPL(vmbus_sendpacket_mpb_desc);
 
@@ -827,7 +823,6 @@ int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel,
        u32 packetlen_aligned;
        struct kvec bufferlist[3];
        u64 aligned_data = 0;
-       bool lock = channel->acquire_ring_lock;
        u32 pfncount = NUM_PAGES_SPANNED(multi_pagebuffer->offset,
                                         multi_pagebuffer->len);
 
@@ -866,7 +861,7 @@ int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel,
        bufferlist[2].iov_base = &aligned_data;
        bufferlist[2].iov_len = (packetlen_aligned - packetlen);
 
-       return hv_ringbuffer_write(channel, bufferlist, 3, lock);
+       return hv_ringbuffer_write(channel, bufferlist, 3);
 }
 EXPORT_SYMBOL_GPL(vmbus_sendpacket_multipagebuffer);
 

diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index b2bb5aa..f33465d 100644 (file)
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -332,7 +332,6 @@ static struct vmbus_channel *alloc_channel(void)
        if (!channel)
                return NULL;
 
-       channel->acquire_ring_lock = true;
        spin_lock_init(&channel->inbound_lock);
        spin_lock_init(&channel->lock);
 

diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
index 558a798..6a9b546 100644 (file)
--- a/drivers/hv/hyperv_vmbus.h
+++ b/drivers/hv/hyperv_vmbus.h
@@ -283,8 +283,7 @@ int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
 void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info);
 
 int hv_ringbuffer_write(struct vmbus_channel *channel,
-                       struct kvec *kv_list,
-                       u32 kv_count, bool lock);
+                       struct kvec *kv_list, u32 kv_count);
 
 int hv_ringbuffer_read(struct vmbus_channel *channel,
                       void *buffer, u32 buflen, u32 *buffer_actual_len,

diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
index 1b70e03..1a1e70a 100644 (file)
--- a/drivers/hv/ring_buffer.c
+++ b/drivers/hv/ring_buffer.c
@@ -284,7 +284,7 @@ void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info)
 
 /* Write to the ring buffer. */
 int hv_ringbuffer_write(struct vmbus_channel *channel,
-                       struct kvec *kv_list, u32 kv_count, bool lock)
+                       struct kvec *kv_list, u32 kv_count)
 {
        int i = 0;
        u32 bytes_avail_towrite;
@@ -304,8 +304,7 @@ int hv_ringbuffer_write(struct vmbus_channel *channel,
 
        totalbytes_towrite += sizeof(u64);
 
-       if (lock)
-               spin_lock_irqsave(&outring_info->ring_lock, flags);
+       spin_lock_irqsave(&outring_info->ring_lock, flags);
 
        bytes_avail_towrite = hv_get_bytes_to_write(outring_info);
 
@@ -315,8 +314,7 @@ int hv_ringbuffer_write(struct vmbus_channel *channel,
         * is empty since the read index == write index.
         */
        if (bytes_avail_towrite <= totalbytes_towrite) {
-               if (lock)
-                       spin_unlock_irqrestore(&outring_info->ring_lock, flags);
+               spin_unlock_irqrestore(&outring_info->ring_lock, flags);
                return -EAGAIN;
        }
 
@@ -347,8 +345,7 @@ int hv_ringbuffer_write(struct vmbus_channel *channel,
        hv_set_next_write_location(outring_info, next_write_location);
 
 
-       if (lock)
-               spin_unlock_irqrestore(&outring_info->ring_lock, flags);
+       spin_unlock_irqrestore(&outring_info->ring_lock, flags);
 
        hv_signal_on_write(old_write, channel);
 

diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index e5aac5c..466374d 100644 (file)
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -846,16 +846,6 @@ struct vmbus_channel {
         */
        struct list_head percpu_list;
        /*
-        * On the channel send side, many of the VMBUS
-        * device drivers explicity serialize access to the
-        * outgoing ring buffer. Give more control to the
-        * VMBUS device drivers in terms how to serialize
-        * accesss to the outgoing ring buffer.
-        * The default behavior will be to aquire the
-        * ring lock to preserve the current behavior.
-        */
-       bool acquire_ring_lock;
-       /*
         * For performance critical channels (storage, networking
         * etc,), Hyper-V has a mechanism to enhance the throughput
         * at the expense of latency:
@@ -895,11 +885,6 @@ struct vmbus_channel {
 
 };
 
-static inline void set_channel_lock_state(struct vmbus_channel *c, bool state)
-{
-       c->acquire_ring_lock = state;
-}
-
 static inline bool is_hvsock_channel(const struct vmbus_channel *c)
 {
        return !!(c->offermsg.offer.chn_flags &