* [PATCH 1/3] Drivers: hv: ring_buffer.c: fix comment style
2015-11-23 16:45 [PATCH 0/3] Drivers: hv: ring_buffer: do some code cleanup Vitaly Kuznetsov
@ 2015-11-23 16:45 ` Vitaly Kuznetsov
2015-11-23 16:45 ` [PATCH 2/3] Drivers: hv: ring_buffer: remove stray smp_read_barrier_depends() Vitaly Kuznetsov
2015-11-23 16:45 ` [PATCH 3/3] Drivers: hv: ring_buffer: remove code duplication from hv_ringbuffer_peek/read() Vitaly Kuznetsov
2 siblings, 0 replies; 4+ messages in thread
From: Vitaly Kuznetsov @ 2015-11-23 16:45 UTC (permalink / raw)
To: devel; +Cc: K. Y. Srinivasan, Haiyang Zhang, linux-kernel
Convert 6+-string comments repeating function names to normal kernel-style
comments and fix a couple of other comment style issues. No textual or
functional changes intended.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
drivers/hv/ring_buffer.c | 135 +++++++++--------------------------------------
1 file changed, 26 insertions(+), 109 deletions(-)
diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
index 70a1a9a..7bca513 100644
--- a/drivers/hv/ring_buffer.c
+++ b/drivers/hv/ring_buffer.c
@@ -112,9 +112,7 @@ static bool hv_need_to_signal_on_read(u32 prev_write_sz,
u32 read_loc = rbi->ring_buffer->read_index;
u32 pending_sz = rbi->ring_buffer->pending_send_sz;
- /*
- * If the other end is not blocked on write don't bother.
- */
+ /* If the other end is not blocked on write don't bother. */
if (pending_sz == 0)
return false;
@@ -128,12 +126,7 @@ static bool hv_need_to_signal_on_read(u32 prev_write_sz,
return false;
}
-/*
- * hv_get_next_write_location()
- *
- * Get the next write location for the specified ring buffer
- *
- */
+/* Get the next write location for the specified ring buffer. */
static inline u32
hv_get_next_write_location(struct hv_ring_buffer_info *ring_info)
{
@@ -142,12 +135,7 @@ hv_get_next_write_location(struct hv_ring_buffer_info *ring_info)
return next;
}
-/*
- * hv_set_next_write_location()
- *
- * Set the next write location for the specified ring buffer
- *
- */
+/* Set the next write location for the specified ring buffer. */
static inline void
hv_set_next_write_location(struct hv_ring_buffer_info *ring_info,
u32 next_write_location)
@@ -155,11 +143,7 @@ hv_set_next_write_location(struct hv_ring_buffer_info *ring_info,
ring_info->ring_buffer->write_index = next_write_location;
}
-/*
- * hv_get_next_read_location()
- *
- * Get the next read location for the specified ring buffer
- */
+/* Get the next read location for the specified ring buffer. */
static inline u32
hv_get_next_read_location(struct hv_ring_buffer_info *ring_info)
{
@@ -169,10 +153,8 @@ hv_get_next_read_location(struct hv_ring_buffer_info *ring_info)
}
/*
- * hv_get_next_readlocation_withoffset()
- *
* Get the next read location + offset for the specified ring buffer.
- * This allows the caller to skip
+ * This allows the caller to skip.
*/
static inline u32
hv_get_next_readlocation_withoffset(struct hv_ring_buffer_info *ring_info,
@@ -186,13 +168,7 @@ hv_get_next_readlocation_withoffset(struct hv_ring_buffer_info *ring_info,
return next;
}
-/*
- *
- * hv_set_next_read_location()
- *
- * Set the next read location for the specified ring buffer
- *
- */
+/* Set the next read location for the specified ring buffer. */
static inline void
hv_set_next_read_location(struct hv_ring_buffer_info *ring_info,
u32 next_read_location)
@@ -201,12 +177,7 @@ hv_set_next_read_location(struct hv_ring_buffer_info *ring_info,
}
-/*
- *
- * hv_get_ring_buffer()
- *
- * Get the start of the ring buffer
- */
+/* Get the start of the ring buffer. */
static inline void *
hv_get_ring_buffer(struct hv_ring_buffer_info *ring_info)
{
@@ -214,25 +185,14 @@ hv_get_ring_buffer(struct hv_ring_buffer_info *ring_info)
}
-/*
- *
- * hv_get_ring_buffersize()
- *
- * Get the size of the ring buffer
- */
+/* Get the size of the ring buffer. */
static inline u32
hv_get_ring_buffersize(struct hv_ring_buffer_info *ring_info)
{
return ring_info->ring_datasize;
}
-/*
- *
- * hv_get_ring_bufferindices()
- *
- * Get the read and write indices as u64 of the specified ring buffer
- *
- */
+/* Get the read and write indices as u64 of the specified ring buffer. */
static inline u64
hv_get_ring_bufferindices(struct hv_ring_buffer_info *ring_info)
{
@@ -240,12 +200,8 @@ hv_get_ring_bufferindices(struct hv_ring_buffer_info *ring_info)
}
/*
- *
- * hv_copyfrom_ringbuffer()
- *
* Helper routine to copy to source from ring buffer.
* Assume there is enough room. Handles wrap-around in src case only!!
- *
*/
static u32 hv_copyfrom_ringbuffer(
struct hv_ring_buffer_info *ring_info,
@@ -277,12 +233,8 @@ static u32 hv_copyfrom_ringbuffer(
/*
- *
- * hv_copyto_ringbuffer()
- *
* Helper routine to copy from source to ring buffer.
* Assume there is enough room. Handles wrap-around in dest case only!!
- *
*/
static u32 hv_copyto_ringbuffer(
struct hv_ring_buffer_info *ring_info,
@@ -308,13 +260,7 @@ static u32 hv_copyto_ringbuffer(
return start_write_offset;
}
-/*
- *
- * hv_ringbuffer_get_debuginfo()
- *
- * Get various debug metrics for the specified ring buffer
- *
- */
+/* Get various debug metrics for the specified ring buffer. */
void hv_ringbuffer_get_debuginfo(struct hv_ring_buffer_info *ring_info,
struct hv_ring_buffer_debug_info *debug_info)
{
@@ -337,13 +283,7 @@ void hv_ringbuffer_get_debuginfo(struct hv_ring_buffer_info *ring_info,
}
}
-/*
- *
- * hv_ringbuffer_init()
- *
- *Initialize the ring buffer
- *
- */
+/* Initialize the ring buffer. */
int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
void *buffer, u32 buflen)
{
@@ -356,9 +296,7 @@ int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
ring_info->ring_buffer->read_index =
ring_info->ring_buffer->write_index = 0;
- /*
- * Set the feature bit for enabling flow control.
- */
+ /* Set the feature bit for enabling flow control. */
ring_info->ring_buffer->feature_bits.value = 1;
ring_info->ring_size = buflen;
@@ -369,24 +307,12 @@ int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
return 0;
}
-/*
- *
- * hv_ringbuffer_cleanup()
- *
- * Cleanup the ring buffer
- *
- */
+/* Cleanup the ring buffer. */
void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info)
{
}
-/*
- *
- * hv_ringbuffer_write()
- *
- * Write to the ring buffer
- *
- */
+/* Write to the ring buffer. */
int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info,
struct kvec *kv_list, u32 kv_count, bool *signal)
{
@@ -411,10 +337,11 @@ int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info,
&bytes_avail_toread,
&bytes_avail_towrite);
-
- /* If there is only room for the packet, assume it is full. */
- /* Otherwise, the next time around, we think the ring buffer */
- /* is empty since the read index == write index */
+ /*
+ * If there is only room for the packet, assume it is full.
+ * Otherwise, the next time around, we think the ring buffer
+ * is empty since the read index == write index.
+ */
if (bytes_avail_towrite <= totalbytes_towrite) {
spin_unlock_irqrestore(&outring_info->ring_lock, flags);
return -EAGAIN;
@@ -454,13 +381,7 @@ int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info,
}
-/*
- *
- * hv_ringbuffer_peek()
- *
- * Read without advancing the read index
- *
- */
+/* Read without advancing the read index. */
int hv_ringbuffer_peek(struct hv_ring_buffer_info *Inring_info,
void *Buffer, u32 buflen)
{
@@ -497,13 +418,7 @@ int hv_ringbuffer_peek(struct hv_ring_buffer_info *Inring_info,
}
-/*
- *
- * hv_ringbuffer_read()
- *
- * Read and advance the read index
- *
- */
+/* Read and advance the read index. */
int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info, void *buffer,
u32 buflen, u32 offset, bool *signal)
{
@@ -542,9 +457,11 @@ int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info, void *buffer,
sizeof(u64),
next_read_location);
- /* Make sure all reads are done before we update the read index since */
- /* the writer may start writing to the read area once the read index */
- /*is updated */
+ /*
+ * Make sure all reads are done before we update the read index since
+ * the writer may start writing to the read area once the read index
+ * is updated.
+ */
mb();
/* Update the read index */
--
2.4.3
^ permalink raw reply [flat|nested] 4+ messages in thread* [PATCH 3/3] Drivers: hv: ring_buffer: remove code duplication from hv_ringbuffer_peek/read()
2015-11-23 16:45 [PATCH 0/3] Drivers: hv: ring_buffer: do some code cleanup Vitaly Kuznetsov
2015-11-23 16:45 ` [PATCH 1/3] Drivers: hv: ring_buffer.c: fix comment style Vitaly Kuznetsov
2015-11-23 16:45 ` [PATCH 2/3] Drivers: hv: ring_buffer: remove stray smp_read_barrier_depends() Vitaly Kuznetsov
@ 2015-11-23 16:45 ` Vitaly Kuznetsov
2 siblings, 0 replies; 4+ messages in thread
From: Vitaly Kuznetsov @ 2015-11-23 16:45 UTC (permalink / raw)
To: devel; +Cc: K. Y. Srinivasan, Haiyang Zhang, linux-kernel
hv_ringbuffer_peek() does the same as hv_ringbuffer_read() without
advancing the read index. The only functional change this patch brings
is moving hv_need_to_signal_on_read() call under the ring_lock but this
function is just a couple of comparisons.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
drivers/hv/ring_buffer.c | 68 ++++++++++++++++++------------------------------
1 file changed, 25 insertions(+), 43 deletions(-)
diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
index 7bca513..07f9408 100644
--- a/drivers/hv/ring_buffer.c
+++ b/drivers/hv/ring_buffer.c
@@ -380,47 +380,9 @@ int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info,
return 0;
}
-
-/* Read without advancing the read index. */
-int hv_ringbuffer_peek(struct hv_ring_buffer_info *Inring_info,
- void *Buffer, u32 buflen)
-{
- u32 bytes_avail_towrite;
- u32 bytes_avail_toread;
- u32 next_read_location = 0;
- unsigned long flags;
-
- spin_lock_irqsave(&Inring_info->ring_lock, flags);
-
- hv_get_ringbuffer_availbytes(Inring_info,
- &bytes_avail_toread,
- &bytes_avail_towrite);
-
- /* Make sure there is something to read */
- if (bytes_avail_toread < buflen) {
-
- spin_unlock_irqrestore(&Inring_info->ring_lock, flags);
-
- return -EAGAIN;
- }
-
- /* Convert to byte offset */
- next_read_location = hv_get_next_read_location(Inring_info);
-
- next_read_location = hv_copyfrom_ringbuffer(Inring_info,
- Buffer,
- buflen,
- next_read_location);
-
- spin_unlock_irqrestore(&Inring_info->ring_lock, flags);
-
- return 0;
-}
-
-
-/* Read and advance the read index. */
-int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info, void *buffer,
- u32 buflen, u32 offset, bool *signal)
+static inline int __hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info,
+ void *buffer, u32 buflen, u32 offset,
+ bool *signal, bool advance)
{
u32 bytes_avail_towrite;
u32 bytes_avail_toread;
@@ -452,6 +414,9 @@ int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info, void *buffer,
buflen,
next_read_location);
+ if (!advance)
+ goto out_unlock;
+
next_read_location = hv_copyfrom_ringbuffer(inring_info,
&prev_indices,
sizeof(u64),
@@ -467,9 +432,26 @@ int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info, void *buffer,
/* Update the read index */
hv_set_next_read_location(inring_info, next_read_location);
- spin_unlock_irqrestore(&inring_info->ring_lock, flags);
-
*signal = hv_need_to_signal_on_read(bytes_avail_towrite, inring_info);
+out_unlock:
+ spin_unlock_irqrestore(&inring_info->ring_lock, flags);
return 0;
}
+
+/* Read from ring buffer without advancing the read index. */
+int hv_ringbuffer_peek(struct hv_ring_buffer_info *inring_info,
+ void *buffer, u32 buflen)
+{
+ return __hv_ringbuffer_read(inring_info, buffer, buflen,
+ 0, NULL, false);
+}
+
+/* Read from ring buffer and advance the read index. */
+int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info,
+ void *buffer, u32 buflen, u32 offset,
+ bool *signal)
+{
+ return __hv_ringbuffer_read(inring_info, buffer, buflen,
+ offset, signal, true);
+}
--
2.4.3
^ permalink raw reply [flat|nested] 4+ messages in thread