[PATCH 11/14] vmbus: remove conditional locking of vmbus_write
Stephen Hemminger
stephen at networkplumber.org
Wed Feb 1 16:28:58 UTC 2017
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 at microsoft.com>
---
drivers/hv/channel.c | 13 ++++---------
drivers/hv/channel_mgmt.c | 1 -
drivers/hv/hyperv_vmbus.h | 3 +--
drivers/hv/ring_buffer.c | 11 ++++-------
include/linux/hyperv.h | 15 ---------------
5 files changed, 9 insertions(+), 34 deletions(-)
diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index 18cc1c78260d..81a80c82f1bd 100644
--- 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 b2bb5aafaa2f..f33465d78a02 100644
--- 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 558a798c407c..6a9b54677218 100644
--- 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 30ca55aefd24..146fd8ab2a2a 100644
--- 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 936e6b9d1fe4..9b0165b11c5c 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -828,16 +828,6 @@ 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:
@@ -877,11 +867,6 @@ 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 &
--
2.11.0
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