> -----Original Message----- > From: Greg KH [mailto:gregkh@xxxxxxxxxxxxxxxxxxx] > Sent: Tuesday, November 28, 2017 7:35 AM > To: KY Srinivasan <kys@xxxxxxxxxxxxx> > Cc: linux-kernel@xxxxxxxxxxxxxxx; devel@xxxxxxxxxxxxxxxxxxxxxx; > olaf@xxxxxxxxx; apw@xxxxxxxxxxxxx; vkuznets@xxxxxxxxxx; > jasowang@xxxxxxxxxx; leann.ogasawara@xxxxxxxxxxxxx; > marcelo.cerri@xxxxxxxxxxxxx; Stephen Hemminger > <sthemmin@xxxxxxxxxxxxx>; Stephen Hemminger > <stephen@xxxxxxxxxxxxxxxxxx> > Subject: Re: [PATCH 2/2] vmbus: make hv_get_ringbuffer_availbytes local > > On Tue, Nov 14, 2017 at 10:52:08AM -0700, kys@xxxxxxxxxxxxxxxxxxxxxx > wrote: > > From: Stephen Hemminger <stephen@xxxxxxxxxxxxxxxxxx> > > > > hv_get_ringbuffer_availbytes is only used by the debug info > > routine so make it static. Also, add READ_ONCE() to avoid any > > possible issues with potentially volatile index values. > > > > Signed-off-by: Stephen Hemminger <sthemmin@xxxxxxxxxxxxx> > > Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> > > --- > > drivers/hv/ring_buffer.c | 23 +++++++++++++++++++++++ > > include/linux/hyperv.h | 22 ---------------------- > > 2 files changed, 23 insertions(+), 22 deletions(-) > > > > diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c > > index 12eb8ca..50e0714 100644 > > --- a/drivers/hv/ring_buffer.c > > +++ b/drivers/hv/ring_buffer.c > > @@ -140,6 +140,29 @@ static u32 hv_copyto_ringbuffer( > > return start_write_offset; > > } > > > > +/* > > + * > > + * hv_get_ringbuffer_availbytes() > > + * > > + * Get number of bytes available to read and to write to > > + * for the specified ring buffer > > + */ > > +static void > > +hv_get_ringbuffer_availbytes(const struct hv_ring_buffer_info *rbi, > > + u32 *read, u32 *write) > > +{ > > + u32 read_loc, write_loc, dsize; > > + > > + /* Capture the read/write indices before they changed */ > > + read_loc = READ_ONCE(rbi->ring_buffer->read_index); > > + write_loc = READ_ONCE(rbi->ring_buffer->write_index); > > + dsize = rbi->ring_datasize; > > + > > + *write = write_loc >= read_loc ? dsize - (write_loc - read_loc) : > > + read_loc - write_loc; > > + *read = dsize - *write; > > +} > > + > > /* Get various debug metrics for the specified ring buffer. */ > > void hv_ringbuffer_get_debuginfo(const struct hv_ring_buffer_info > *ring_info, > > struct hv_ring_buffer_debug_info > *debug_info) > > diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h > > index 6c93366..93bd6fc 100644 > > --- a/include/linux/hyperv.h > > +++ b/include/linux/hyperv.h > > @@ -127,28 +127,6 @@ struct hv_ring_buffer_info { > > u32 priv_read_index; > > }; > > > > -/* > > - * > > - * hv_get_ringbuffer_availbytes() > > - * > > - * Get number of bytes available to read and to write to > > - * for the specified ring buffer > > - */ > > -static inline void > > -hv_get_ringbuffer_availbytes(const struct hv_ring_buffer_info *rbi, > > - u32 *read, u32 *write) > > -{ > > - u32 read_loc, write_loc, dsize; > > - > > - /* Capture the read/write indices before they changed */ > > - read_loc = rbi->ring_buffer->read_index; > > - write_loc = rbi->ring_buffer->write_index; > > - dsize = rbi->ring_datasize; > > - > > - *write = write_loc >= read_loc ? dsize - (write_loc - read_loc) : > > - read_loc - write_loc; > > - *read = dsize - *write; > > -} > > > > static inline u32 hv_get_bytes_to_read(const struct hv_ring_buffer_info > *rbi) > > { > > -- > > 1.7.1 > > This breaks the build. > > Please be more careful... Sorry about that. I did not have a build issue on the tree I tested. I will rebase and send. K. Y > > greg k-h _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
