weiping zhang
2017-Dec-26 13:35 UTC
[RFC PATCH] virtio: add space for device features show
make features string more readable, add space every 8bit. example: 00101010 01110000 00000000 00001100 Signed-off-by: weiping zhang <zhangweiping at didichuxing.com> --- drivers/virtio/virtio.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index 59e36ef..d7d2db1 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -50,9 +50,12 @@ static ssize_t features_show(struct device *_d, /* We actually represent this as a bitstring, as it could be * arbitrary length in future. */ - for (i = 0; i < sizeof(dev->features)*8; i++) - len += sprintf(buf+len, "%c", + for (i = 0; i < sizeof(dev->features) * 8; i++) { + len += sprintf(buf + len, "%c", __virtio_test_bit(dev, i) ? '1' : '0'); + if (i % 8 == 7) + len += sprintf(buf + len, " "); + } len += sprintf(buf+len, "\n"); return len; } -- 2.9.4
Cornelia Huck
2018-Jan-08 12:50 UTC
[RFC PATCH] virtio: add space for device features show
On Tue, 26 Dec 2017 21:35:44 +0800 weiping zhang <zhangweiping at didichuxing.com> wrote:> make features string more readable, add space every 8bit. > example: > 00101010 01110000 00000000 00001100 > > Signed-off-by: weiping zhang <zhangweiping at didichuxing.com> > --- > drivers/virtio/virtio.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c > index 59e36ef..d7d2db1 100644 > --- a/drivers/virtio/virtio.c > +++ b/drivers/virtio/virtio.c > @@ -50,9 +50,12 @@ static ssize_t features_show(struct device *_d, > > /* We actually represent this as a bitstring, as it could be > * arbitrary length in future. */ > - for (i = 0; i < sizeof(dev->features)*8; i++) > - len += sprintf(buf+len, "%c", > + for (i = 0; i < sizeof(dev->features) * 8; i++) { > + len += sprintf(buf + len, "%c", > __virtio_test_bit(dev, i) ? '1' : '0'); > + if (i % 8 == 7) > + len += sprintf(buf + len, " "); > + } > len += sprintf(buf+len, "\n"); > return len; > }This might break consumers of this attribute. I think the better approach is to write a userspace tool that can do additional helpful stuff (like decoding the feature bits).