12f85fa320
Keeping a global discovery log page was meant to be a time saving
mechanism, but in the current implementation, it doesn't work properly,
and can cause undesirable behavior and potential crashes. There are two
main problems with keeping a global log page.
1. Admin qpairs can be assigned to any SPDK thread. This means that when
multiple initiators connect to the host and request the discovery log,
they can both be running through the spdk_nvmf_ctrlr_get_log_page
function at the same time. In the event that the discovery generation
counter is incremented while these accesses are occurring, it can cause
one or both of the threads to update the log at the same time. This
results in both logs trying to free the old log page (double free) and
set their log as the new one (possible memory leak).
2. The second problem is that each host is supposed to get a unique
discovery log based on the subsystems to which they have access.
Currently the code relies on whether the discovery log page offset in
the request is equal to 0 to determine if it should load a new discovery
log page or use the cached one. This is inherently faulty because it
relies on initiator provided value to determine what information to
provide from the log page. An initiator could easily send a discovery
request with an offset greater than 0 on purpose to procure most of a
log page provided to another host.
Overall, I think it's safest to not cache the log page at all anymore
and rely on a thread local fresh log page each time.
Reported-by: Curt Bruns <curt.e.bruns@intel.com>
Signed-off-by: Seth Howell <seth.howell@intel.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/466839 (master)
(cherry picked from commit
|
||
|---|---|---|
| .githooks | ||
| app | ||
| build/lib | ||
| doc | ||
| dpdk@6ed84b28a0 | ||
| dpdkbuild | ||
| etc/spdk | ||
| examples | ||
| go | ||
| include | ||
| intel-ipsec-mb@489ec6082a | ||
| ipsecbuild | ||
| isa-l@09e787231b | ||
| isalbuild | ||
| lib | ||
| mk | ||
| module | ||
| ocf@515137f25e | ||
| pkg | ||
| scripts | ||
| shared_lib | ||
| test | ||
| .astylerc | ||
| .gitignore | ||
| .gitmodules | ||
| autobuild.sh | ||
| autopackage.sh | ||
| autorun_post.py | ||
| autorun.sh | ||
| autotest.sh | ||
| CHANGELOG.md | ||
| CONFIG | ||
| configure | ||
| CONTRIBUTING.md | ||
| ISSUE_TEMPLATE.md | ||
| LICENSE | ||
| Makefile | ||
| README.md | ||
Storage Performance Development Kit
The Storage Performance Development Kit (SPDK) provides a set of tools and libraries for writing high performance, scalable, user-mode storage applications. It achieves high performance by moving all of the necessary drivers into userspace and operating in a polled mode instead of relying on interrupts, which avoids kernel context switches and eliminates interrupt handling overhead.
The development kit currently includes:
- NVMe driver
- I/OAT (DMA engine) driver
- NVMe over Fabrics target
- iSCSI target
- vhost target
- Virtio-SCSI driver
In this readme:
- Documentation
- Prerequisites
- Source Code
- Build
- Unit Tests
- Vagrant
- Advanced Build Options
- Shared libraries
- Hugepages and Device Binding
- Example Code
- Contributing
Documentation
Doxygen API documentation is available, as well as a Porting Guide for porting SPDK to different frameworks and operating systems.
Source Code
git clone https://github.com/spdk/spdk
cd spdk
git submodule update --init
Prerequisites
The dependencies can be installed automatically by scripts/pkgdep.sh.
./scripts/pkgdep.sh
Build
Linux:
./configure
make
FreeBSD: Note: Make sure you have the matching kernel source in /usr/src/ and also note that CONFIG_COVERAGE option is not available right now for FreeBSD builds.
./configure
gmake
Unit Tests
./test/unit/unittest.sh
You will see several error messages when running the unit tests, but they are part of the test suite. The final message at the end of the script indicates success or failure.
Vagrant
A Vagrant setup is also provided to create a Linux VM with a virtual NVMe controller to get up and running quickly. Currently this has only been tested on MacOS and Ubuntu 16.04.2 LTS with the VirtualBox provider. The VirtualBox Extension Pack must also be installed in order to get the required NVMe support.
Details on the Vagrant setup can be found in the SPDK Vagrant documentation.
Advanced Build Options
Optional components and other build-time configuration are controlled by
settings in the Makefile configuration file in the root of the repository. CONFIG
contains the base settings for the configure script. This script generates a new
file, mk/config.mk, that contains final build settings. For advanced configuration,
there are a number of additional options to configure that may be used, or
mk/config.mk can simply be created and edited by hand. A description of all
possible options is located in CONFIG.
Boolean (on/off) options are configured with a 'y' (yes) or 'n' (no). For
example, this line of CONFIG controls whether the optional RDMA (libibverbs)
support is enabled:
CONFIG_RDMA?=n
To enable RDMA, this line may be added to mk/config.mk with a 'y' instead of
'n'. For the majority of options this can be done using the configure script.
For example:
./configure --with-rdma
Additionally, CONFIG options may also be overridden on the make command
line:
make CONFIG_RDMA=y
Users may wish to use a version of DPDK different from the submodule included in the SPDK repository. Note, this includes the ability to build not only from DPDK sources, but also just with the includes and libraries installed via the dpdk and dpdk-devel packages. To specify an alternate DPDK installation, run configure with the --with-dpdk option. For example:
Linux:
./configure --with-dpdk=/path/to/dpdk/x86_64-native-linuxapp-gcc
make
FreeBSD:
./configure --with-dpdk=/path/to/dpdk/x86_64-native-bsdapp-clang
gmake
The options specified on the make command line take precedence over the
values in mk/config.mk. This can be useful if you, for example, generate
a mk/config.mk using the configure script and then have one or two
options (i.e. debug builds) that you wish to turn on and off frequently.
Shared libraries
By default, the build of the SPDK yields static libraries against which
the SPDK applications and examples are linked.
Configure option --with-shared provides the ability to produce SPDK shared
libraries, in addition to the default static ones. Use of this flag also
results in the SPDK executables linked to the shared versions of libraries.
SPDK shared libraries by default, are located in ./build/lib. This includes
the single SPDK shared lib encompassing all of the SPDK static libs
(libspdk.so) as well as individual SPDK shared libs corresponding to each
of the SPDK static ones.
In order to start a SPDK app linked with SPDK shared libraries, make sure to do the following steps:
- run ldconfig specifying the directory containing SPDK shared libraries
- provide proper
LD_LIBRARY_PATH
Linux:
./configure --with-shared
make
ldconfig -v -n ./build/lib
LD_LIBRARY_PATH=./build/lib/ ./app/spdk_tgt/spdk_tgt
Hugepages and Device Binding
Before running an SPDK application, some hugepages must be allocated and any NVMe and I/OAT devices must be unbound from the native kernel drivers. SPDK includes a script to automate this process on both Linux and FreeBSD. This script should be run as root.
sudo scripts/setup.sh
Users may wish to configure a specific memory size. Below is an example of configuring 8192MB memory.
sudo HUGEMEM=8192 scripts/setup.sh
Example Code
Example code is located in the examples directory. The examples are compiled automatically as part of the build process. Simply call any of the examples with no arguments to see the help output. You'll likely need to run the examples as a privileged user (root) unless you've done additional configuration to grant your user permission to allocate huge pages and map devices through vfio.
Contributing
For additional details on how to get more involved in the community, including contributing code and participating in discussions and other activities, please refer to spdk.io