svn commit: r276236 - head/share/man/man4

[Joel Dahl]

Author: joel (doc committer)
Date: Fri Dec 26 09:35:23 2014
New Revision: 276236
URL: https://svnweb.freebsd.org/changeset/base/276236

Log:
  Minor mdoc fixes.

Modified:
  head/share/man/man4/netmap.4

Modified: head/share/man/man4/netmap.4
==============================================================================
--- head/share/man/man4/netmap.4	Fri Dec 26 09:18:33 2014	(r276235)
+++ head/share/man/man4/netmap.4	Fri Dec 26 09:35:23 2014	(r276236)
@@ -243,7 +243,6 @@ contains the index of the first of these
 which are connected in a list (the first uint32_t of each
 buffer being the index of the next buffer in the list).
 A 0 indicates the end of the list.
-.Pp
 .It Dv struct netmap_ring (one per ring)
 .Bd -literal
 struct netmap_ring {
@@ -266,7 +265,6 @@ Implements transmit and receive rings, w
 pointers, metadata and and an array of
 .Pa slots
 describing the buffers.
-.Pp
 .It Dv struct netmap_slot (one per buffer)
 .Bd -literal
 struct netmap_slot {
@@ -367,7 +365,6 @@ are pushed to the port, and
 .Va tail
 may advance if further slots have become available.
 Below is an example of the evolution of a TX ring:
-.Pp
 .Bd -literal
     after the syscall, slots between cur and tail are (a)vailable
               head=cur   tail
@@ -455,7 +452,6 @@ it MUST be used when the buf_idx in the 
 This can be used to implement
 zero-copy forwarding, see
 .Sx ZERO-COPY FORWARDING .
-.Pp
 .It NS_REPORT
 reports when this buffer has been transmitted.
 Normally,
@@ -533,7 +529,6 @@ A file descriptor obtained through
 .Pa /dev/netmap
 also supports the ioctl supported by network devices, see
 .Xr netintro 4 .
-.Pp
 .Bl -tag -width XXXX
 .It Dv NIOCGINFO
 returns EINVAL if the named port does not support netmap.
@@ -541,7 +536,6 @@ Otherwise, it returns 0 and (advisory) i
 about the port.
 Note that all the information below can change before the
 interface is actually put in netmap mode.
-.Pp
 .Bl -tag -width XX
 .It Pa nr_memsize
 indicates the size of the
@@ -603,7 +597,6 @@ that application libraries (such as the
 .Nm nm_open
 indicated below) can use to indicate the specific set of rings.
 In the example below, "netmap:foo" is any valid netmap port name.
-.Pp
 .Bl -tag -width XXXXX
 .It NR_REG_ALL_NIC                         "netmap:foo"
 (default) all hardware ring pairs
@@ -784,7 +777,6 @@ are controlled through sysctl variables 
 .Em ( dev.netmap.* )
 and module parameters on Linux
 .Em ( /sys/module/netmap_lin/parameters/* ) :
-.Pp
 .Bl -tag -width indent
 .It Va dev.netmap.admode: 0
 Controls the use of native or emulated adapter mode.
@@ -852,42 +844,6 @@ OS primitives, see
 In particular,
 .Xr pthread_setaffinity_np 3
 may be of use.
-.Sh CAVEATS
-No matter how fast the CPU and OS are,
-achieving line rate on 10G and faster interfaces
-requires hardware with sufficient performance.
-Several NICs are unable to sustain line rate with
-small packet sizes. Insufficient PCIe or memory bandwidth
-can also cause reduced performance.
-.Pp
-Another frequent reason for low performance is the use
-of flow control on the link: a slow receiver can limit
-the transmit speed.
-Be sure to disable flow control when running high
-speed experiments.
-.Pp
-.Ss SPECIAL NIC FEATURES
-.Nm
-is orthogonal to some NIC features such as
-multiqueue, schedulers, packet filters.
-.Pp
-Multiple transmit and receive rings are supported natively
-and can be configured with ordinary OS tools,
-such as
-.Xr ethtool
-or
-device-specific sysctl variables.
-The same goes for Receive Packet Steering (RPS)
-and filtering of incoming traffic.
-.Pp
-.Nm
-.Em does not use
-features such as
-.Em checksum offloading , TCP segmentation offloading ,
-.Em encryption , VLAN encapsulation/decapsulation ,
-etc. .
-When using netmap to exchange packets with the host stack,
-make sure to disable these features.
 .Sh EXAMPLES
 .Ss TEST PROGRAMS
 .Nm
@@ -1065,3 +1021,39 @@ and
 .Nm VALE
 have been funded by the European Commission within FP7 Projects
 CHANGE (257422) and OPENLAB (287581).
+.Sh CAVEATS
+No matter how fast the CPU and OS are,
+achieving line rate on 10G and faster interfaces
+requires hardware with sufficient performance.
+Several NICs are unable to sustain line rate with
+small packet sizes. Insufficient PCIe or memory bandwidth
+can also cause reduced performance.
+.Pp
+Another frequent reason for low performance is the use
+of flow control on the link: a slow receiver can limit
+the transmit speed.
+Be sure to disable flow control when running high
+speed experiments.
+.Pp
+.Ss SPECIAL NIC FEATURES
+.Nm
+is orthogonal to some NIC features such as
+multiqueue, schedulers, packet filters.
+.Pp
+Multiple transmit and receive rings are supported natively
+and can be configured with ordinary OS tools,
+such as
+.Xr ethtool
+or
+device-specific sysctl variables.
+The same goes for Receive Packet Steering (RPS)
+and filtering of incoming traffic.
+.Pp
+.Nm
+.Em does not use
+features such as
+.Em checksum offloading , TCP segmentation offloading ,
+.Em encryption , VLAN encapsulation/decapsulation ,
+etc. .
+When using netmap to exchange packets with the host stack,
+make sure to disable these features.