From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- Documentation/infiniband/ipoib.txt | 56 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) create mode 100644 Documentation/infiniband/ipoib.txt (limited to 'Documentation/infiniband/ipoib.txt') diff --git a/Documentation/infiniband/ipoib.txt b/Documentation/infiniband/ipoib.txt new file mode 100644 index 00000000000..18e184b5604 --- /dev/null +++ b/Documentation/infiniband/ipoib.txt @@ -0,0 +1,56 @@ +IP OVER INFINIBAND + + The ib_ipoib driver is an implementation of the IP over InfiniBand + protocol as specified by the latest Internet-Drafts issued by the + IETF ipoib working group. It is a "native" implementation in the + sense of setting the interface type to ARPHRD_INFINIBAND and the + hardware address length to 20 (earlier proprietary implementations + masqueraded to the kernel as ethernet interfaces). + +Partitions and P_Keys + + When the IPoIB driver is loaded, it creates one interface for each + port using the P_Key at index 0. To create an interface with a + different P_Key, write the desired P_Key into the main interface's + /sys/class/net//create_child file. For example: + + echo 0x8001 > /sys/class/net/ib0/create_child + + This will create an interface named ib0.8001 with P_Key 0x8001. To + remove a subinterface, use the "delete_child" file: + + echo 0x8001 > /sys/class/net/ib0/delete_child + + The P_Key for any interface is given by the "pkey" file, and the + main interface for a subinterface is in "parent." + +Debugging Information + + By compiling the IPoIB driver with CONFIG_INFINIBAND_IPOIB_DEBUG set + to 'y', tracing messages are compiled into the driver. They are + turned on by setting the module parameters debug_level and + mcast_debug_level to 1. These parameters can be controlled at + runtime through files in /sys/module/ib_ipoib/. + + CONFIG_INFINIBAND_IPOIB_DEBUG also enables the "ipoib_debugfs" + virtual filesystem. By mounting this filesystem, for example with + + mkdir -p /ipoib_debugfs + mount -t ipoib_debugfs none /ipoib_debufs + + it is possible to get statistics about multicast groups from the + files /ipoib_debugfs/ib0_mcg and so on. + + The performance impact of this option is negligible, so it + is safe to enable this option with debug_level set to 0 for normal + operation. + + CONFIG_INFINIBAND_IPOIB_DEBUG_DATA enables even more debug output in + the data path when data_debug_level is set to 1. However, even with + the output disabled, enabling this configuration option will affect + performance, because it adds tests to the fast path. + +References + + IETF IP over InfiniBand (ipoib) Working Group + http://ietf.org/html.charters/ipoib-charter.html -- cgit v1.2.3