[PATCH 02/10] docs: sphinxify coccinelle.txt and add it to dev-tools
From: Jonathan Corbet
Date: Mon Aug 08 2016 - 19:35:40 EST
No textual changes have been made, but the formatting has obviously been
tweaked.
Cc: Michal Marek <mmarek@xxxxxxxx>
Cc: Gilles Muller <Gilles.Muller@xxxxxxx>
Cc: Nicolas Palix <nicolas.palix@xxxxxxx>
Cc: Julia Lawall <julia.lawall@xxxxxxx>
Signed-off-by: Jonathan Corbet <corbet@xxxxxxx>
---
.../{coccinelle.txt => dev-tools/coccinelle.rst} | 359 +++++++++++----------
Documentation/dev-tools/tools.rst | 1 +
MAINTAINERS | 2 +-
3 files changed, 192 insertions(+), 170 deletions(-)
rename Documentation/{coccinelle.txt => dev-tools/coccinelle.rst} (56%)
diff --git a/Documentation/coccinelle.txt b/Documentation/dev-tools/coccinelle.rst
similarity index 56%
rename from Documentation/coccinelle.txt
rename to Documentation/dev-tools/coccinelle.rst
index 01fb1da..4a64b4c 100644
--- a/Documentation/coccinelle.txt
+++ b/Documentation/dev-tools/coccinelle.rst
@@ -1,10 +1,18 @@
-Copyright 2010 Nicolas Palix <npalix@xxxxxxx>
-Copyright 2010 Julia Lawall <julia@xxxxxxx>
-Copyright 2010 Gilles Muller <Gilles.Muller@xxxxxxx>
+.. Copyright 2010 Nicolas Palix <npalix@xxxxxxx>
+.. Copyright 2010 Julia Lawall <julia@xxxxxxx>
+.. Copyright 2010 Gilles Muller <Gilles.Muller@xxxxxxx>
+.. highlight:: none
- Getting Coccinelle
-~~~~~~~~~~~~~~~~~~~~
+Coccinelle
+==========
+
+Coccinelle is a tool for pattern matching and text transformation that has
+many uses in kernel development, including the application of complex,
+tree-wide patches and detection of problematic programming patterns.
+
+Getting Coccinelle
+-------------------
The semantic patches included in the kernel use features and options
which are provided by Coccinelle version 1.0.0-rc11 and above.
@@ -22,24 +30,23 @@ of many distributions, e.g. :
- NetBSD
- FreeBSD
-
You can get the latest version released from the Coccinelle homepage at
http://coccinelle.lip6.fr/
Information and tips about Coccinelle are also provided on the wiki
pages at http://cocci.ekstranet.diku.dk/wiki/doku.php
-Once you have it, run the following command:
+Once you have it, run the following command::
./configure
make
-as a regular user, and install it with
+as a regular user, and install it with::
sudo make install
- Supplemental documentation
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Supplemental documentation
+---------------------------
For supplemental documentation refer to the wiki:
@@ -47,49 +54,52 @@ https://bottest.wiki.kernel.org/coccicheck
The wiki documentation always refers to the linux-next version of the script.
- Using Coccinelle on the Linux kernel
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Using Coccinelle on the Linux kernel
+------------------------------------
A Coccinelle-specific target is defined in the top level
-Makefile. This target is named 'coccicheck' and calls the 'coccicheck'
-front-end in the 'scripts' directory.
+Makefile. This target is named ``coccicheck`` and calls the ``coccicheck``
+front-end in the ``scripts`` directory.
-Four basic modes are defined: patch, report, context, and org. The mode to
-use is specified by setting the MODE variable with 'MODE=<mode>'.
+Four basic modes are defined: ``patch``, ``report``, ``context``, and
+``org``. The mode to use is specified by setting the MODE variable with
+``MODE=<mode>``.
-'patch' proposes a fix, when possible.
+- ``patch`` proposes a fix, when possible.
-'report' generates a list in the following format:
+- ``report`` generates a list in the following format:
file:line:column-column: message
-'context' highlights lines of interest and their context in a
-diff-like style.Lines of interest are indicated with '-'.
+- ``context`` highlights lines of interest and their context in a
+ diff-like style.Lines of interest are indicated with ``-``.
-'org' generates a report in the Org mode format of Emacs.
+- ``org`` generates a report in the Org mode format of Emacs.
Note that not all semantic patches implement all modes. For easy use
of Coccinelle, the default mode is "report".
Two other modes provide some common combinations of these modes.
-'chain' tries the previous modes in the order above until one succeeds.
+- ``chain`` tries the previous modes in the order above until one succeeds.
+
+- ``rep+ctxt`` runs successively the report mode and the context mode.
+ It should be used with the C option (described later)
+ which checks the code on a file basis.
-'rep+ctxt' runs successively the report mode and the context mode.
- It should be used with the C option (described later)
- which checks the code on a file basis.
+Examples
+~~~~~~~~
-Examples:
- To make a report for every semantic patch, run the following command:
+To make a report for every semantic patch, run the following command::
make coccicheck MODE=report
- To produce patches, run:
+To produce patches, run::
make coccicheck MODE=patch
The coccicheck target applies every semantic patch available in the
-sub-directories of 'scripts/coccinelle' to the entire Linux kernel.
+sub-directories of ``scripts/coccinelle`` to the entire Linux kernel.
For each semantic patch, a commit message is proposed. It gives a
description of the problem being checked by the semantic patch, and
@@ -99,15 +109,15 @@ As any static code analyzer, Coccinelle produces false
positives. Thus, reports must be carefully checked, and patches
reviewed.
-To enable verbose messages set the V= variable, for example:
+To enable verbose messages set the V= variable, for example::
make coccicheck MODE=report V=1
- Coccinelle parallelization
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Coccinelle parallelization
+---------------------------
By default, coccicheck tries to run as parallel as possible. To change
-the parallelism, set the J= variable. For example, to run across 4 CPUs:
+the parallelism, set the J= variable. For example, to run across 4 CPUs::
make coccicheck MODE=report J=4
@@ -115,44 +125,47 @@ As of Coccinelle 1.0.2 Coccinelle uses Ocaml parmap for parallelization,
if support for this is detected you will benefit from parmap parallelization.
When parmap is enabled coccicheck will enable dynamic load balancing by using
-'--chunksize 1' argument, this ensures we keep feeding threads with work
+``--chunksize 1`` argument, this ensures we keep feeding threads with work
one by one, so that we avoid the situation where most work gets done by only
a few threads. With dynamic load balancing, if a thread finishes early we keep
feeding it more work.
When parmap is enabled, if an error occurs in Coccinelle, this error
-value is propagated back, the return value of the 'make coccicheck'
+value is propagated back, the return value of the ``make coccicheck``
captures this return value.
- Using Coccinelle with a single semantic patch
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Using Coccinelle with a single semantic patch
+---------------------------------------------
The optional make variable COCCI can be used to check a single
semantic patch. In that case, the variable must be initialized with
the name of the semantic patch to apply.
-For instance:
+For instance::
make coccicheck COCCI=<my_SP.cocci> MODE=patch
-or
+
+or::
+
make coccicheck COCCI=<my_SP.cocci> MODE=report
- Controlling Which Files are Processed by Coccinelle
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Controlling Which Files are Processed by Coccinelle
+---------------------------------------------------
+
By default the entire kernel source tree is checked.
-To apply Coccinelle to a specific directory, M= can be used.
-For example, to check drivers/net/wireless/ one may write:
+To apply Coccinelle to a specific directory, ``M=`` can be used.
+For example, to check drivers/net/wireless/ one may write::
make coccicheck M=drivers/net/wireless/
To apply Coccinelle on a file basis, instead of a directory basis, the
-following command may be used:
+following command may be used::
make C=1 CHECK="scripts/coccicheck"
-To check only newly edited code, use the value 2 for the C flag, i.e.
+To check only newly edited code, use the value 2 for the C flag, i.e.::
make C=2 CHECK="scripts/coccicheck"
@@ -166,8 +179,8 @@ semantic patch as shown in the previous section.
The "report" mode is the default. You can select another one with the
MODE variable explained above.
- Debugging Coccinelle SmPL patches
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Debugging Coccinelle SmPL patches
+---------------------------------
Using coccicheck is best as it provides in the spatch command line
include options matching the options used when we compile the kernel.
@@ -177,8 +190,8 @@ manually run Coccinelle with debug options added.
Alternatively you can debug running Coccinelle against SmPL patches
by asking for stderr to be redirected to stderr, by default stderr
is redirected to /dev/null, if you'd like to capture stderr you
-can specify the DEBUG_FILE="file.txt" option to coccicheck. For
-instance:
+can specify the ``DEBUG_FILE="file.txt"`` option to coccicheck. For
+instance::
rm -f cocci.err
make coccicheck COCCI=scripts/coccinelle/free/kfree.cocci MODE=report DEBUG_FILE=cocci.err
@@ -186,7 +199,7 @@ instance:
You can use SPFLAGS to add debugging flags, for instance you may want to
add both --profile --show-trying to SPFLAGS when debugging. For instance
-you may want to use:
+you may want to use::
rm -f err.log
export COCCI=scripts/coccinelle/misc/irqf_oneshot.cocci
@@ -198,24 +211,24 @@ work.
DEBUG_FILE support is only supported when using coccinelle >= 1.2.
- .cocciconfig support
-~~~~~~~~~~~~~~~~~~~~~~
+.cocciconfig support
+--------------------
Coccinelle supports reading .cocciconfig for default Coccinelle options that
should be used every time spatch is spawned, the order of precedence for
variables for .cocciconfig is as follows:
- o Your current user's home directory is processed first
- o Your directory from which spatch is called is processed next
- o The directory provided with the --dir option is processed last, if used
+- Your current user's home directory is processed first
+- Your directory from which spatch is called is processed next
+- The directory provided with the --dir option is processed last, if used
Since coccicheck runs through make, it naturally runs from the kernel
proper dir, as such the second rule above would be implied for picking up a
-.cocciconfig when using 'make coccicheck'.
+.cocciconfig when using ``make coccicheck``.
-'make coccicheck' also supports using M= targets.If you do not supply
+``make coccicheck`` also supports using M= targets.If you do not supply
any M= target, it is assumed you want to target the entire kernel.
-The kernel coccicheck script has:
+The kernel coccicheck script has::
if [ "$KBUILD_EXTMOD" = "" ] ; then
OPTIONS="--dir $srctree $COCCIINCLUDE"
@@ -235,12 +248,12 @@ override any of the kernel's .coccicheck's settings using SPFLAGS.
We help Coccinelle when used against Linux with a set of sensible defaults
options for Linux with our own Linux .cocciconfig. This hints to coccinelle
-git can be used for 'git grep' queries over coccigrep. A timeout of 200
+git can be used for ``git grep`` queries over coccigrep. A timeout of 200
seconds should suffice for now.
The options picked up by coccinelle when reading a .cocciconfig do not appear
as arguments to spatch processes running on your system, to confirm what
-options will be used by Coccinelle run:
+options will be used by Coccinelle run::
spatch --print-options-only
@@ -252,219 +265,227 @@ carries its own .cocciconfig, you will need to use SPFLAGS to use idutils if
desired. See below section "Additional flags" for more details on how to use
idutils.
- Additional flags
-~~~~~~~~~~~~~~~~~~
+Additional flags
+----------------
Additional flags can be passed to spatch through the SPFLAGS
variable. This works as Coccinelle respects the last flags
-given to it when options are in conflict.
+given to it when options are in conflict. ::
make SPFLAGS=--use-glimpse coccicheck
Coccinelle supports idutils as well but requires coccinelle >= 1.0.6.
When no ID file is specified coccinelle assumes your ID database file
is in the file .id-utils.index on the top level of the kernel, coccinelle
-carries a script scripts/idutils_index.sh which creates the database with
+carries a script scripts/idutils_index.sh which creates the database with::
mkid -i C --output .id-utils.index
If you have another database filename you can also just symlink with this
-name.
+name. ::
make SPFLAGS=--use-idutils coccicheck
Alternatively you can specify the database filename explicitly, for
-instance:
+instance::
make SPFLAGS="--use-idutils /full-path/to/ID" coccicheck
-See spatch --help to learn more about spatch options.
+See ``spatch --help`` to learn more about spatch options.
-Note that the '--use-glimpse' and '--use-idutils' options
+Note that the ``--use-glimpse`` and ``--use-idutils`` options
require external tools for indexing the code. None of them is
thus active by default. However, by indexing the code with
one of these tools, and according to the cocci file used,
spatch could proceed the entire code base more quickly.
- SmPL patch specific options
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+SmPL patch specific options
+---------------------------
SmPL patches can have their own requirements for options passed
to Coccinelle. SmPL patch specific options can be provided by
-providing them at the top of the SmPL patch, for instance:
+providing them at the top of the SmPL patch, for instance::
-// Options: --no-includes --include-headers
+ // Options: --no-includes --include-headers
- SmPL patch Coccinelle requirements
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+SmPL patch Coccinelle requirements
+----------------------------------
As Coccinelle features get added some more advanced SmPL patches
may require newer versions of Coccinelle. If an SmPL patch requires
at least a version of Coccinelle, this can be specified as follows,
-as an example if requiring at least Coccinelle >= 1.0.5:
+as an example if requiring at least Coccinelle >= 1.0.5::
-// Requires: 1.0.5
+ // Requires: 1.0.5
- Proposing new semantic patches
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Proposing new semantic patches
+-------------------------------
New semantic patches can be proposed and submitted by kernel
developers. For sake of clarity, they should be organized in the
-sub-directories of 'scripts/coccinelle/'.
+sub-directories of ``scripts/coccinelle/``.
- Detailed description of the 'report' mode
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Detailed description of the ``report`` mode
+-------------------------------------------
+
+``report`` generates a list in the following format::
-'report' generates a list in the following format:
file:line:column-column: message
-Example:
+Example
+~~~~~~~
-Running
+Running::
make coccicheck MODE=report COCCI=scripts/coccinelle/api/err_cast.cocci
-will execute the following part of the SmPL script.
+will execute the following part of the SmPL script::
-<smpl>
-@r depends on !context && !patch && (org || report)@
-expression x;
-position p;
-@@
+ <smpl>
+ @r depends on !context && !patch && (org || report)@
+ expression x;
+ position p;
+ @@
- ERR_PTR@p(PTR_ERR(x))
+ ERR_PTR@p(PTR_ERR(x))
-@script:python depends on report@
-p << r.p;
-x << r.x;
-@@
+ @script:python depends on report@
+ p << r.p;
+ x << r.x;
+ @@
-msg="ERR_CAST can be used with %s" % (x)
-coccilib.report.print_report(p[0], msg)
-</smpl>
+ msg="ERR_CAST can be used with %s" % (x)
+ coccilib.report.print_report(p[0], msg)
+ </smpl>
This SmPL excerpt generates entries on the standard output, as
-illustrated below:
+illustrated below::
-/home/user/linux/crypto/ctr.c:188:9-16: ERR_CAST can be used with alg
-/home/user/linux/crypto/authenc.c:619:9-16: ERR_CAST can be used with auth
-/home/user/linux/crypto/xts.c:227:9-16: ERR_CAST can be used with alg
+ /home/user/linux/crypto/ctr.c:188:9-16: ERR_CAST can be used with alg
+ /home/user/linux/crypto/authenc.c:619:9-16: ERR_CAST can be used with auth
+ /home/user/linux/crypto/xts.c:227:9-16: ERR_CAST can be used with alg
- Detailed description of the 'patch' mode
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Detailed description of the ``patch`` mode
+------------------------------------------
-When the 'patch' mode is available, it proposes a fix for each problem
+When the ``patch`` mode is available, it proposes a fix for each problem
identified.
-Example:
+Example
+~~~~~~~
+
+Running::
-Running
make coccicheck MODE=patch COCCI=scripts/coccinelle/api/err_cast.cocci
-will execute the following part of the SmPL script.
+will execute the following part of the SmPL script::
-<smpl>
-@ depends on !context && patch && !org && !report @
-expression x;
-@@
+ <smpl>
+ @ depends on !context && patch && !org && !report @
+ expression x;
+ @@
-- ERR_PTR(PTR_ERR(x))
-+ ERR_CAST(x)
-</smpl>
+ - ERR_PTR(PTR_ERR(x))
+ + ERR_CAST(x)
+ </smpl>
This SmPL excerpt generates patch hunks on the standard output, as
-illustrated below:
+illustrated below::
-diff -u -p a/crypto/ctr.c b/crypto/ctr.c
---- a/crypto/ctr.c 2010-05-26 10:49:38.000000000 +0200
-+++ b/crypto/ctr.c 2010-06-03 23:44:49.000000000 +0200
-@@ -185,7 +185,7 @@ static struct crypto_instance *crypto_ct
+ diff -u -p a/crypto/ctr.c b/crypto/ctr.c
+ --- a/crypto/ctr.c 2010-05-26 10:49:38.000000000 +0200
+ +++ b/crypto/ctr.c 2010-06-03 23:44:49.000000000 +0200
+ @@ -185,7 +185,7 @@ static struct crypto_instance *crypto_ct
alg = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_CIPHER,
CRYPTO_ALG_TYPE_MASK);
if (IS_ERR(alg))
-- return ERR_PTR(PTR_ERR(alg));
-+ return ERR_CAST(alg);
-
+ - return ERR_PTR(PTR_ERR(alg));
+ + return ERR_CAST(alg);
+
/* Block size must be >= 4 bytes. */
err = -EINVAL;
- Detailed description of the 'context' mode
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Detailed description of the ``context`` mode
+--------------------------------------------
-'context' highlights lines of interest and their context
+``context`` highlights lines of interest and their context
in a diff-like style.
-NOTE: The diff-like output generated is NOT an applicable patch. The
- intent of the 'context' mode is to highlight the important lines
- (annotated with minus, '-') and gives some surrounding context
+ **NOTE**: The diff-like output generated is NOT an applicable patch. The
+ intent of the ``context`` mode is to highlight the important lines
+ (annotated with minus, ``-``) and gives some surrounding context
lines around. This output can be used with the diff mode of
Emacs to review the code.
-Example:
+Example
+~~~~~~~
+
+Running::
-Running
make coccicheck MODE=context COCCI=scripts/coccinelle/api/err_cast.cocci
-will execute the following part of the SmPL script.
+will execute the following part of the SmPL script::
-<smpl>
-@ depends on context && !patch && !org && !report@
-expression x;
-@@
+ <smpl>
+ @ depends on context && !patch && !org && !report@
+ expression x;
+ @@
-* ERR_PTR(PTR_ERR(x))
-</smpl>
+ * ERR_PTR(PTR_ERR(x))
+ </smpl>
This SmPL excerpt generates diff hunks on the standard output, as
-illustrated below:
+illustrated below::
-diff -u -p /home/user/linux/crypto/ctr.c /tmp/nothing
---- /home/user/linux/crypto/ctr.c 2010-05-26 10:49:38.000000000 +0200
-+++ /tmp/nothing
-@@ -185,7 +185,6 @@ static struct crypto_instance *crypto_ct
+ diff -u -p /home/user/linux/crypto/ctr.c /tmp/nothing
+ --- /home/user/linux/crypto/ctr.c 2010-05-26 10:49:38.000000000 +0200
+ +++ /tmp/nothing
+ @@ -185,7 +185,6 @@ static struct crypto_instance *crypto_ct
alg = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_CIPHER,
CRYPTO_ALG_TYPE_MASK);
if (IS_ERR(alg))
-- return ERR_PTR(PTR_ERR(alg));
-
+ - return ERR_PTR(PTR_ERR(alg));
+
/* Block size must be >= 4 bytes. */
err = -EINVAL;
- Detailed description of the 'org' mode
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Detailed description of the ``org`` mode
+----------------------------------------
+
+``org`` generates a report in the Org mode format of Emacs.
-'org' generates a report in the Org mode format of Emacs.
+Example
+~~~~~~~
-Example:
+Running::
-Running
make coccicheck MODE=org COCCI=scripts/coccinelle/api/err_cast.cocci
-will execute the following part of the SmPL script.
+will execute the following part of the SmPL script::
-<smpl>
-@r depends on !context && !patch && (org || report)@
-expression x;
-position p;
-@@
+ <smpl>
+ @r depends on !context && !patch && (org || report)@
+ expression x;
+ position p;
+ @@
- ERR_PTR@p(PTR_ERR(x))
+ ERR_PTR@p(PTR_ERR(x))
-@script:python depends on org@
-p << r.p;
-x << r.x;
-@@
+ @script:python depends on org@
+ p << r.p;
+ x << r.x;
+ @@
-msg="ERR_CAST can be used with %s" % (x)
-msg_safe=msg.replace("[","@(").replace("]",")")
-coccilib.org.print_todo(p[0], msg_safe)
-</smpl>
+ msg="ERR_CAST can be used with %s" % (x)
+ msg_safe=msg.replace("[","@(").replace("]",")")
+ coccilib.org.print_todo(p[0], msg_safe)
+ </smpl>
This SmPL excerpt generates Org entries on the standard output, as
-illustrated below:
+illustrated below::
-* TODO [[view:/home/user/linux/crypto/ctr.c::face=ovl-face1::linb=188::colb=9::cole=16][ERR_CAST can be used with alg]]
-* TODO [[view:/home/user/linux/crypto/authenc.c::face=ovl-face1::linb=619::colb=9::cole=16][ERR_CAST can be used with auth]]
-* TODO [[view:/home/user/linux/crypto/xts.c::face=ovl-face1::linb=227::colb=9::cole=16][ERR_CAST can be used with alg]]
+ * TODO [[view:/home/user/linux/crypto/ctr.c::face=ovl-face1::linb=188::colb=9::cole=16][ERR_CAST can be used with alg]]
+ * TODO [[view:/home/user/linux/crypto/authenc.c::face=ovl-face1::linb=619::colb=9::cole=16][ERR_CAST can be used with auth]]
+ * TODO [[view:/home/user/linux/crypto/xts.c::face=ovl-face1::linb=227::colb=9::cole=16][ERR_CAST can be used with alg]]
diff --git a/Documentation/dev-tools/tools.rst b/Documentation/dev-tools/tools.rst
index 60ddb9e..ae0c58c 100644
--- a/Documentation/dev-tools/tools.rst
+++ b/Documentation/dev-tools/tools.rst
@@ -14,3 +14,4 @@ whole; patches welcome!
.. toctree::
:maxdepth: 2
+ coccinelle
diff --git a/MAINTAINERS b/MAINTAINERS
index 20bb1d0..1e5460c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3124,7 +3124,7 @@ L: cocci@xxxxxxxxxxxxxxx (moderated for non-subscribers)
T: git git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild.git misc
W: http://coccinelle.lip6.fr/
S: Supported
-F: Documentation/coccinelle.txt
+F: Documentation/dev-tools/coccinelle.rst
F: scripts/coccinelle/
F: scripts/coccicheck
--
2.9.2