path: root/SubmittingPatches

How to Submit Patches for Open vSwitch
======================================

Send changes to Open vSwitch as patches to discuss@openvswitch.org.
One patch per email, please.  More details are included below.

If you are using Git, then "git format-patch" takes care of most of
the mechanics described below for you.

Before You Start
----------------

Before you send patches at all, make sure that each patch makes sense.
In particular:

        - A given patch should not break anything, even if later
          patches fix the problems that it causes.  The source tree
          should still build and work after each patch is applied.
          (This enables "git bisect" to work best.)

        - A patch should make one logical change.  Don't make
          multiple, logically unconnected changes to disparate
          subsystems in a single patch.

        - A patch that adds or removes user-visible features should
          also update the appropriate user documentation or manpages.

Testing is also important:

        - A patch that adds or deletes files should be tested with
          "make distcheck" before submission.

        - A patch that modifies Linux kernel code should be at least
          build-tested on various Linux kernel versions before
          submission.  I suggest versions 2.6.18, 2.6.27, and whatever
          the current latest release version is at the time.

        - A patch that modifies the ofproto or vswitchd code should be
          tested in at least simple cases before submission.

        - A patch that modifies xenserver code should be tested on
          XenServer before submission.

Email Subject
-------------

The subject line of your email should be in the following format:
[PATCH <n>/<m>] <area>: <summary>

        - [PATCH <n>/<m>] indicates that this is the nth of a series
          of m patches.  It helps reviewers to read patches in the
          correct order.  You may omit this prefix if you are sending
          only one patch.

        - <area>: indicates the area of the Open vSwitch to which the
          change applies (often the name of a source file or a
          directory).  You may omit it if the change crosses multiple
          distinct pieces of code.

        - <summary> briefly describes the change.

The subject, minus the [PATCH <n>/<m>] prefix, becomes the first line
of the commit's change log message.

Description
-----------

The body of the email should start with a more thorough description of
the change.  This becomes the body of the commit message, following
the subject.  There is no need to duplicate the summary given in the
subject.

Please limit lines in the description to 79 characters in width.

The description should include:

        - The rationale for the change.

        - Design description and rationale (but this might be better
          added as code comments).

        - Testing that you performed (or testing that should be done
          but you could not for whatever reason).

There is no need to describe what the patch actually changed, if the
reader can see it for himself.

If the patch refers to a commit already in the Open vSwitch
repository, please include both the commit number and the subject of
the patch, e.g. 'commit 632d136c "vswitch: Remove restriction on
datapath names."'.

If you, the person sending the patch, did not write the patch
yourself, then the very first line of the body should take the form
"From: <author name> <author email>", followed by a blank line.  This
will automatically cause the named author to be credited with
authorship in the repository.  If others contributed to the patch, but
are not the main authors, then please credit them as part of the
description (e.g. "Thanks to Bob J. User for reporting this bug.").

Comments
--------

If you want to include any comments in your email that should not be
part of the commit's change log message, put them after the
description, separated by a line that contains just "---".  It may be
helpful to include a diffstat here for changes that touch multiple
files.

Patch
-----

The patch should be in the body of the email following the descrition,
separated by a blank line.

Patches should be in "diff -up" format.  We recommend that you use Git
to produce your patches, in which case you should use the -M -C
options to "git diff" (or other Git tools) if your patch renames or
copies files.  Quilt (http://savannah.nongnu.org/projects/quilt) might
be useful if you do not want to use Git.

Patches should be inline in the email message.  Some email clients
corrupt white space or wrap lines in patches.  There are hints on how
to configure many email clients to avoid this problem at:
        http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blob_plain;f=Documentation/email-clients.txt
If you cannot convince your email client not to mangle patches, then
sending the patch as an attachment is a second choice.

Please follow the style used in the code that you are modifying.  The
CodingStyle file describes the coding style used in most of Open
vSwitch.  Use Linux kernel coding style for Linux kernel code.

Example
-------

From 632d136c7b108cd3d39a2e64fe6230e23977caf8 Mon Sep 17 00:00:00 2001
From: Ben Pfaff <blp@nicira.com>
Date: Mon, 6 Jul 2009 10:17:54 -0700
Subject: [PATCH] vswitch: Remove restriction on datapath names.

Commit f4b96c92c "vswitch: Disallow bridges named "dpN" or "nl:N"" disabled
naming bridges "dpN" because the vswitchd code made the bad assumption that
the bridge's local port has the same name as the bridge, which was not
true (at the time) for bridges named dpN.  Now that assumption has been
eliminated, so this commit eliminates the restriction too.

This change is also a cleanup in that it eliminates one form of the
vswitch's dependence on specifics of the dpif implementation.
---
 vswitchd/bridge.c               |   23 +++++------------------
 vswitchd/ovs-vswitchd.conf.5.in |    3 +--
 2 files changed, 6 insertions(+), 20 deletions(-)

diff --git a/vswitchd/bridge.c b/vswitchd/bridge.c
index 32647ea..00cffbc 100644
--- a/vswitchd/bridge.c
+++ b/vswitchd/bridge.c
@@ -351,32 +351,19 @@ bridge_configure_ssl(void)
 void
 bridge_reconfigure(void)
 {
-    struct svec old_br, new_br, raw_new_br;
+    struct svec old_br, new_br;
     struct bridge *br, *next;
     size_t i, j;
 
     COVERAGE_INC(bridge_reconfigure);
 
-    /* Collect old bridges. */
+    /* Collect old and new bridges. */
     svec_init(&old_br);
+    svec_init(&new_br);
     LIST_FOR_EACH (br, struct bridge, node, &all_bridges) {
         svec_add(&old_br, br->name);
     }
-
-    /* Collect new bridges. */
-    svec_init(&raw_new_br);
-    cfg_get_subsections(&raw_new_br, "bridge");
-    svec_init(&new_br);
-    for (i = 0; i < raw_new_br.n; i++) {
-        const char *name = raw_new_br.names[i];
-        if (!strncmp(name, "dp", 2) && isdigit((unsigned char)name[2])) {
-            VLOG_ERR("%s is not a valid bridge name (bridges may not be "
-                     "named \"dp\" followed by a digit)", name);
-        } else {
-            svec_add(&new_br, name);
-        }
-    }
-    svec_destroy(&raw_new_br);
+    cfg_get_subsections(&new_br, "bridge");
 
     /* Get rid of deleted bridges and add new bridges. */
     svec_sort(&old_br);
@@ -793,7 +780,7 @@ bridge_create(const char *name)
     br = xzalloc(sizeof *br);
 
     error = dpif_create(name, &br->dpif);
-    if (error == EEXIST) {
+    if (error == EEXIST || error == EBUSY) {
         error = dpif_open(name, &br->dpif);
         if (error) {
             VLOG_ERR("datapath %s already exists but cannot be opened: %s",
diff --git a/vswitchd/ovs-vswitchd.conf.5.in b/vswitchd/ovs-vswitchd.conf.5.in
index 5483ad5..d82a08a 100644
--- a/vswitchd/ovs-vswitchd.conf.5.in
+++ b/vswitchd/ovs-vswitchd.conf.5.in
@@ -50,8 +50,7 @@ configure \fBovs\-vswitchd\fR.
 .SS "Bridge Configuration"
 A bridge (switch) with a given \fIname\fR is configured by specifying
 the names of its network devices as values for key
-\fBbridge.\fIname\fB.port\fR.  (The specified \fIname\fR may not begin
-with \fBdp\fR followed by a digit.)
+\fBbridge.\fIname\fB.port\fR.
 .PP
 The names given on \fBbridge.\fIname\fB.port\fR must be the names of
 existing network devices, except for ``internal ports.''  An internal
-- 
1.6.3.3