Linux port of DTrace Feb 2013 Paul D. Fox paul.d.fox@gmail.com http://www.twitter.com/crispeditor http://www.crisp.demon.co.uk Blog - latest news and stuff about the dtrace project: http://crtags.blogspot.com/ http://www.crisp.demon.co.uk/blog/ Download dtrace tarballs for linux here: https://github.com/dtrace4linux/linux ftp://crisp.dynalias.com/pub/release/website/dtrace My public dropbox, likely out of date: http://dl.dropbox.com/u/45405441/dtrace-latest.tar.gz Introduction ============ This is a port of the Sun DTrace user and kernel code to Linux. No linux kernel code is touched in this build, but what is produced is a dynamically loadable kernel module. This avoids licensing issues and allows people to load and update dtrace as they desire. The goal of this project is to make available DTrace for the Linux platforms. By making it available for everyone, they can use it to optimise their systems and tools, and in return, I get to benefit from their work. PayPal ====== If you want to make a donation for this software, feel free to do so. Nothing is asked of you - it is genuinely free software, but it can help guage interest and appreciation if you do. You can pay by visiting the link below and clicking on "Donate", or use this reference for donations: foxpaypal@crisp.demon.co.uk Licensing ========= The original DTrace is licensed under Sun's (now Oracle) CDDL license. Original copyrights are left intact. No GPL code is incorporated into the release, to avoid legal conflicts. Any mistakes or omissions in copyright attribution will be my mistake, so please let me know if there are such cases. The linux kernel was referred to in order to engineer the glue for dtrace behavior, and there is no intention of making this code fall under anything other than CDDL. (If Oracle migrate to a GPL friendly license, then this port of dtrace can follow). I do not own the license or assert any rights on the licensing other than that expected of me as a consumer/supplier. I have no political affiliation or preference for a licensing scheme, simply that Sun/Oracle has gracefully donated to the community a large body of work. I reserve the right to change the licensing model for my own code at a later date, when and if someone puts forward a case as to the correct license agreement. If the code is useful to you - great. Spread it around and get people to use, debug and enhance it. GIT Repository ============== https://github.com/dtrace4linux/linux (Theres an older and orphaned github repository under Peter McCormicks name, please ignore this as it has not been updated in a long while and is no longer active). Installation ============ You may need to grab some extra packages for building DTrace. Use either of the following to download extra packages. This list may be incomplete depending on the version of your kernel/distro. $ tools/get-deps.pl # if using Ubuntu $ tools/get-deps-fedora.sh # RedHat/Fedora $ make all $ make install $ make load (need to be root or have sudo access) More details ============ Building is done in a build/ directory. The makefiles allow you to compile for alternate kernel releases in the same tree, which is useful for cross-version checking. The result is: build/dtrace User land executable build/drti.o Object file for USDT apps build/driver/dtracedrv.ko Kernel loadable module Installing will copy them to Solaris compliant locations: /usr/sbin/dtrace /usr/lib/dtrace/64/drti.o You dont need to 'install' to run dtrace, but you will need to load the driver. Kernel versioning ================= dtrace relies on a kernel module and so a binary is needed per system you deploy to, or kernel version. dtrace is sensitive to the kernel - and attempts to cater for that, but very old, or very new kernels may not have been validated. Please feed back if that is the case. No Linux Kernel source modifications required ============================================= This is important for a number of reasons -- unless dtrace is accepted into the kernel, it has to live with changes to header files and data structures. Also, from a licensing perspective it is not valid for dtrace to touch your sources. It is also much easier to not even require kernel sources - so long as a kernel build environment is available. INSTALLATION ============ Run 'make' with no arguments to see the current options. make all to compile the drivers and user space commands. Check the file Packages, for hints on what you need (not much, but libelf, kernel source, flex/yacc -- bison will do). make install Copy dtrace binary and driver to correct install location. make load To load the drivers, and then you can play with cmd/dtrace/dtrace. make unl to unload the drivers. make test To run the userland cmd/dtrace regression test For AS4/Centos ============== yum install elfutils-libelf-devel