| Message ID | 1429657085-23379-1-git-send-email-sixiao@microsoft.com |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | David Miller |
| Headers | show |
From: sixiao@microsoft.com Date: Tue, 21 Apr 2015 15:58:05 -0700 > From: Simon Xiao <sixiao@microsoft.com> > > Signed-off-by: Simon Xiao <sixiao@microsoft.com> > Reviewed-by: K. Y. Srinivasan <kys@microsoft.com> > Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com> I just gave you feedback on this patch in response to your original submission, do not ignore it. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
> -----Original Message----- > From: David Miller [mailto:davem@davemloft.net] > Sent: Tuesday, April 21, 2015 2:49 PM > To: Simon Xiao > Cc: KY Srinivasan; Haiyang Zhang; devel@linuxdriverproject.org; > netdev@vger.kernel.org; linux-kernel@vger.kernel.org > Subject: Re: [PATCH net-next,1/1] hv_netvsc: call dump_rndis_message() only in > netvsc debug mode > > From: sixiao@microsoft.com > Date: Tue, 21 Apr 2015 15:58:05 -0700 > > > From: Simon Xiao <sixiao@microsoft.com> > > > > Signed-off-by: Simon Xiao <sixiao@microsoft.com> > > Reviewed-by: K. Y. Srinivasan <kys@microsoft.com> > > Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com> > > I just gave you feedback on this patch in response to your original submission, > do not ignore it. Thanks for your feedback, David. In current netvsc driver, for each packet received, it will call dump_rndis_message() to try to dump the rndis packet information by netdev_dbg(). In non-debug mode, dump_rndis_message() will not dump anything but it still initialize some local variables and process the switch logic in the function of dump_rndis_message(), which is unnecessary, especially in high network throughput situation. My change is to have a run-time config flag to control the execution of dump_rndis_message() and avoid above unnecessary cost in non-debug mode. In the default case, it will be non-debug mode, and rndis_filter_receive() will not call dump_rndis_message() which saves the above extra cost for each packet received. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Simon Xiao <sixiao@microsoft.com> Date: Tue, 21 Apr 2015 22:14:14 +0000 > In current netvsc driver, for each packet received, it will call > dump_rndis_message() to try to dump the rndis packet information by > netdev_dbg(). In non-debug mode, dump_rndis_message() will not dump > anything but it still initialize some local variables and process > the switch logic in the function of dump_rndis_message(), which is > unnecessary, especially in high network throughput situation. See NETIF_MSG_* and use it properly in your driver, read other drivers and learn how to properly use it for things like this. I'm not going to explain this a third time. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
sixiao@microsoft.com writes: > From: Simon Xiao <sixiao@microsoft.com> > > Signed-off-by: Simon Xiao <sixiao@microsoft.com> > Reviewed-by: K. Y. Srinivasan <kys@microsoft.com> > Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com> I don't quite understand what problem is being solved here (and empty commit message doesn't is not very helpful). netdev_dbg() is not being printed by default and in case if floods logs with too many messages you can change it to net_dbg_ratelimited(). We already have dynamic debug and adding another module parameter shouldn't be needed... > --- > drivers/net/hyperv/hyperv_net.h | 3 +++ > drivers/net/hyperv/netvsc_drv.c | 8 ++++++++ > drivers/net/hyperv/rndis_filter.c | 3 ++- > 3 files changed, 13 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h > index a10b316..c9be35e 100644 > --- a/drivers/net/hyperv/hyperv_net.h > +++ b/drivers/net/hyperv/hyperv_net.h > @@ -28,6 +28,9 @@ > #include <linux/hyperv.h> > #include <linux/rndis.h> > > +/* flag for netvsc debug mode */ > +extern int debug_mode; > + > /* RSS related */ > #define OID_GEN_RECEIVE_SCALE_CAPABILITIES 0x00010203 /* query only */ > #define OID_GEN_RECEIVE_SCALE_PARAMETERS 0x00010204 /* query and set */ > diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c > index a3a9d38..7c41864 100644 > --- a/drivers/net/hyperv/netvsc_drv.c > +++ b/drivers/net/hyperv/netvsc_drv.c > @@ -52,6 +52,10 @@ static int ring_size = 128; > module_param(ring_size, int, S_IRUGO); > MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)"); > > +int debug_mode = 0; > +module_param(debug_mode, int, S_IRUGO); > +MODULE_PARM_DESC(debug_mode, "debug mode: zero(0) for non-debug mode; non-zero for debug mode"); > + > static void do_set_multicast(struct work_struct *w) > { > struct net_device_context *ndevctx = > @@ -999,6 +1003,10 @@ static int __init netvsc_drv_init(void) > pr_info("Increased ring_size to %d (min allowed)\n", > ring_size); > } > + > + if (debug_mode != 0) > + pr_info("Run netvsc in debug mode"); > + > return vmbus_driver_register(&netvsc_drv); > } > > diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c > index 0d92efe..a3f43f6 100644 > --- a/drivers/net/hyperv/rndis_filter.c > +++ b/drivers/net/hyperv/rndis_filter.c > @@ -429,7 +429,8 @@ int rndis_filter_receive(struct hv_device *dev, > > rndis_msg = pkt->data; > > - dump_rndis_message(dev, rndis_msg); > + if (debug_mode != 0) > + dump_rndis_message(dev, rndis_msg); > > switch (rndis_msg->ndis_msg_type) { > case RNDIS_MSG_PACKET:
diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h index a10b316..c9be35e 100644 --- a/drivers/net/hyperv/hyperv_net.h +++ b/drivers/net/hyperv/hyperv_net.h @@ -28,6 +28,9 @@ #include <linux/hyperv.h> #include <linux/rndis.h> +/* flag for netvsc debug mode */ +extern int debug_mode; + /* RSS related */ #define OID_GEN_RECEIVE_SCALE_CAPABILITIES 0x00010203 /* query only */ #define OID_GEN_RECEIVE_SCALE_PARAMETERS 0x00010204 /* query and set */ diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index a3a9d38..7c41864 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -52,6 +52,10 @@ static int ring_size = 128; module_param(ring_size, int, S_IRUGO); MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)"); +int debug_mode = 0; +module_param(debug_mode, int, S_IRUGO); +MODULE_PARM_DESC(debug_mode, "debug mode: zero(0) for non-debug mode; non-zero for debug mode"); + static void do_set_multicast(struct work_struct *w) { struct net_device_context *ndevctx = @@ -999,6 +1003,10 @@ static int __init netvsc_drv_init(void) pr_info("Increased ring_size to %d (min allowed)\n", ring_size); } + + if (debug_mode != 0) + pr_info("Run netvsc in debug mode"); + return vmbus_driver_register(&netvsc_drv); } diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c index 0d92efe..a3f43f6 100644 --- a/drivers/net/hyperv/rndis_filter.c +++ b/drivers/net/hyperv/rndis_filter.c @@ -429,7 +429,8 @@ int rndis_filter_receive(struct hv_device *dev, rndis_msg = pkt->data; - dump_rndis_message(dev, rndis_msg); + if (debug_mode != 0) + dump_rndis_message(dev, rndis_msg); switch (rndis_msg->ndis_msg_type) { case RNDIS_MSG_PACKET: