Installing NDCTL and DAXCTL from Source on Linux

These instructions provide a step-by-step guide for installing the ndctl and daxctl utilities from the GitHub project master branch.

1. Install the Prerequisites

There are a number of packages required for the build steps that may not be installed by default. For information about the required packages, see the "BuildRequires:" lines in ndctl.spec.in.

https://github.com/pmem/ndctl/blob/master/ndctl.spec.in

To successfully compile ndctl and daxctl from source with documentation, the following packages are required

• autoconf

• automake

• asciidoc (asciidoctor)

• bash-completion

• doxygen

• gcc

• gcc-c++ (g++)

• git

• glib2

• glib2-devel

• graphviz

• json-c-devel

• keyutils-libs-devel (libkeyutils-dev)

• kmod

• kmod-devel

• libfabric

• libfabric-devel

• libtool

• libudev-devel

• libuuid-devel

• ncurses

• pandoc

• pkg-config

• rubygem-asciidoctor (asciidoctor)

• xmlto

To install these prerequisites, use:

Fedora

Fedora 21 or earlier

sudo yum install git gcc gcc-c++ autoconf automake asciidoc asciidoctor xmlto libtool pkg-config glib2 glib2-devel libfabric libfabric-devel doxygen graphviz pandoc ncurses kmod kmod-devel libudev-devel libuuid-devel json-c-devel keyutils-libs-devel

Fedora 22 or later

sudo dnf install git gcc gcc-c++ autoconf automake asciidoc asciidoctor xmlto libtool pkg-config glib2 glib2-devel libfabric libfabric-devel doxygen graphviz pandoc ncurses kmod kmod-devel libudev-devel libuuid-devel json-c-devel keyutils-libs-devel

RHEL & CentOS

Ubuntu & Debian

2. Clone the GitHub Repository

2.1) If you're behind a company proxy, configure git to work with your proxy server first. The following configures a HTTP and HTTPS proxy for all users. Refer to the git-config documentation for more options and information.

git config --global http.proxy http://proxyUsername:[email protected]:port
git config --global https.proxy https://proxyUsername:[email protected]:port

2.2) Create a working directory to clone the ndctl GitHub repository to, eg: 'downloads'

mkdir ~/downloads

2.3) Clone the repository:

cd ~/downloads
git clone https://github.com/pmem/ndctl
cd ndctl

3. Build

The following configures ndctl to be installed in to the /usr/local directory.

./autogen.sh
./configure CFLAGS='-g -O2' --prefix=/usr/local --sysconfdir=/etc --libdir=/usr/local/lib64
make

For a full list of configure options use:

./configure --help

Build using an alternative compiler

Note: If you want to compile with a different compiler other than gcc, you have to provide the CC and CXX environment variables. For example:

make CC=clang CXX=clang++

These variables are independent and setting CC=clang does not set CXX=clang++.

Build a Debug Version

To compile ndctl with debugging, use the --enable-debug option:

./autogen.sh
./configure CFLAGS='-g -O2' --enable-debug --prefix=/usr/local --sysconfdir=/etc --libdir=/usr/local/lib64
make

The ndctl code uses many statically defined functions which the compiler will optimize as inline assembly when referenced only once. This means the function name is removed from the ELF symbol table and tools such as gdb, ltrace, or bpftrace cannot show this information. It can make it more difficult to understand code flow or troubleshoot issues. Use the -fno-inline -g3 -O0 options to compile ndctl with no optimizations to make all symbols (functions) available for tracing, use:

./autogen.sh
./configure CFLAGS='-fno-inline -g3 -O0' --enable-debug --prefix=/usr/local --sysconfdir=/etc --libdir=/usr/local/lib64
make

4. Install

Once ndctl has successfully been compiled, it can be installed using the following:

sudo make install

5. Build and Run Unit Tests (Optional)

The unit tests run by make check require the nfit_test.ko module to be loaded. To build and install nfit_test.ko:

1. Obtain the kernel source. For example, git clone -b libnvdimm-for-next git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm.git

2. Skip to step 3 if the kernel version is >= v4.8. Otherwise, for kernel versions < v4.8, configure the kernel to make some memory available to CMA (contiguous memory allocator). This will be used to emulate DAX. CONFIG_DMA_CMA=y CONFIG_CMA_SIZE_MBYTES=200 or cma=200M on the kernel command line.

3. Compile the libnvdimm sub-system as a module, make sure "zone device" memory is enabled, and enable the btt, pfn, and dax features of the sub-system: CONFIG_X86_PMEM_LEGACY=m CONFIG_ZONE_DEVICE=y CONFIG_LIBNVDIMM=m CONFIG_BLK_DEV_PMEM=m CONFIG_ND_BLK=m CONFIG_BTT=y CONFIG_NVDIMM_PFN=y CONFIG_NVDIMM_DAX=y CONFIG_DEV_DAX_PMEM=m

4. Build and install the unit test enabled libnvdimm modules in the following order. The unit test modules need to be in place prior to the depmod that runs during the final modules_install make M=tools/testing/nvdimm sudo make M=tools/testing/nvdimm modules_install sudo make modules_install

5. Now run make check in the ndctl source directory, or ndctl test, if ndctl was built with --enable-test.

Troubleshooting

The unit tests will validate that the environment is set up correctly before they try to run. If the platform is misconfigured, i.e. the unit test modules are not available, or the test versions of the modules are superseded by the "in-tree/production" version of the modules make check will skip tests and report a message like the following in test/test-suite.log:

SKIP: libndctl
==============
test/init: nfit_test_init: nfit.ko: appears to be production version: /lib/modules/4.8.8-200.fc24.x86_64/kernel/drivers/acpi/nfit/nfit.ko.xz
__ndctl_test_skip: explicit skip test_libndctl:2684
nfit_test unavailable skipping tests

If the unit test modules are indeed available in the modules 'extra' directory the default depmod policy can be overridden by adding a file to /etc/depmod.d with the following contents:

override nfit * extra
override device_dax * extra
override dax_pmem * extra
override libnvdimm * extra
override nd_blk * extra
override nd_btt * extra
override nd_e820 * extra
override nd_pmem * extra

The nfit_test module emulates pmem with memory allocated via vmalloc(). One of the side effects is that this breaks 'physically contiguous' assumptions in the driver. Use the --align=4K option to ndctl create-namespace to avoid these corner case scenarios.