[[meta copyright="Copyright © 2008 Free Software Foundation, Inc."]] [[meta license="""[[toggle id="license" text="GFDL 1.2+"]][[toggleable id="license" text="Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled [[GNU_Free_Documentation_License|/fdl]]."]]"""]] [[!meta title="GNU/Linux compatible procfs"]] [[!toc ]] ---- Project Name ---- GNU/Linux compatible procfs pseudo-filesystem ------ Project Description ---- I wish to provide a sophisticated procfs pseudo-filesystem to “the Hurd”. An implementation of /proc pseudo-filesystem already exists in hurdextras repository. After skimming through the code it is clear that it needs a lot of rework and tuning. Experiences from GNU/Linux have proven procfs to be a very useful facility in implementing many of the process management tools. So the goal of this project is to rework on the existing procfs on “the Hurd” so that its not only reliable and robust but also more importantly it is fully compatible with the GNU/Linux procfs. The project thus aims at making the GNU/Linux process management tools like top, sysctl, kill, skill, nice, snice, pgrep, free, tload, uptime, fuser, killall, pidof, pstree, etc., to run out of the box. ------ Mentor ---- Olaf Buddenhagen ------ Project Schedule ---- #####     1. Initial preparation and migration (Community Bonding Period: has already started – May 25th) This phase involves improving my translator programming skills by gaining hands-on experience in it and becoming well versed in it. I will also go through the Hurd code to understand its architecture in depth and will read documentations related to obtaining process related information in Hurd. This phase also involves the migration of existing procfs to use libnetfs. #####     2. Analysis and Design (May 26th – June 11th ) This phase involves the analysis of previous migration. Also involves interacting with the mentor, the Hurd community and other people involved in development of ps. tools to draw the exact design of the proposed procfs including the algorithms required for coding. #####     3.  Coding Stage I (June 12th – June 22nd ) Finishing up the migration to libnetfs based on the finalized design and making necessary changes to the existing procfs. Coding up to /proc//exe in the features list. #####     4. Coding Stage II (June 23rd – July 13th) Involves coding of the features from /proc//environ, up to /proc//maps. These contain most of the information required for ps. tools and hence form the heart of the project. Will be completed by mid-term evaluation deadline. #####     5.  Coding Stage III (July 14th – July 26th ) Coding the rest of the features in the list including any necessary features that may be added in the analysis phase. #####     6.  Final Testing and evaluation (July 27th – August 8th ) Closely interacting with the community and requesting them to help me in overall testing and reviewing and making changes as per their suggestions. Also involves testing with the ps. tools and consolidating the documentation. #####     7.  Packaging and Wrap-up (August 9th - August 18th ) Final phase of testing and fixing remaining bugs. Working with the community to merge the project with the CVS HEAD of Hurd. Documentation reviews, making necessary changes as per the suggestions and wrapping up the documentation. ------ Deliverables ---- 1. /proc filesystem that uses libnetfs. Using this library makes it easier for implementing a large set of functionalities and hence makes the implementation robust. 2. The core GNU/Linux compatible /proc filesystem with functionalities to support and provide information for ps. tools like procps, psmisc etc. Non-code deliverables include an exhaustive Documentation. This documents the code of the Hurd's procfs which explains in detail the implementation of each of the functionalities of procfs implemented during the course of this project. ------ Code Repository ---- [http://github.com/madhusudancs/procfs/tree/master](http://github.com/madhusudancs/procfs/tree/master) Clone URL: [git://github.com/madhusudancs/procfs.git](git://github.com/madhusudancs/procfs.git) ------ Progress ---- 1. Packages Ported: [http://www.madhusudancs.info/parted-hurdi386 parted-1.7.1] 2. Packages Porting in progress: autogen_1:5.9.4-1. Error installing texlive-bin. Error tracked to some post installation scripts of texlive-bin. Problem seems to be in fmutil. Trying to debug. 3. Have to start coding libnetfs skeleton for procfs translator. **Target for next week** Task To be completed by Status Now 1. Finish Defining the necessary netfs call backs                                 25-05-2008            Completed 2. Create Directories for each process with pid directory name         27-05-2008            Completed 3. Create stat file for each process within this directory and
put atleast 1 information into it                                                          31-05-2008            In Progress **Documentations Read/Reading** 1. [Hurd Hacking Guide](http://www.gnu.org/software/hurd/hacking-guide/hhg.html) (Have Concentrated mainly on Translator part) 2. [Linux Kernel Implementation of procfs](http://users.sosdg.org/~qiyong/lxr/source/Documentation/filesystems/proc.txt) **Code Being Read** 1. libps 2. libnetfs 3. [procfs implementation in Linux kernel](http://users.sosdg.org/~qiyong/lxr/source/fs/proc/) 4. ftpfs (In Hurd main) 5. cvsfs (In Hurd extras) 6. xmlfs (In Hurd extras) 7. httpfs (In Hurd extras) 8. gopherfs (In Hurd extras) 9. libfuse (In Hurd extras) 10. procfs (libtrivfs based, In Hurd extras) ------ Post Mid-Term Road Map ---- Legend *** - I know where the information is available roughly, but need to look in detail to extract the exact information. **** - The information may be available, but needs to be searched to know where it will be. ***** - I fear information may not be available. ~~~~~ - Need not be implemented. ####Already Implemented #####File - /proc/<PID>/stat * pid * comm * state * ppid * pgrp * session * tty_nr * tpgid * minflt The number of minor faults the process has made which have not required loading a memory page from disk. * majflt The number of major faults the process has made which have required loading a memory page from disk. * utime The number of jiffies that this process has been scheduled in user mode. * stime The number of jiffies that this process has been scheduled in kernel mode. ####I already know the where the information is exactly available. * *** cminflt The number of minor faults that the process’s waited-for children have made. * *** cmajflt The number of major faults that the process’s waited-for children have made. * ** cutime The number of jiffies that this process’s waited-for children have been scheduled in user mode. * ** cstime The number of jiffies that this process’s waited-for children have been scheduled in kernel mode. * ** priority The standard nice value, plus fifteen. The value is never negative in the kernel. * *** nice The nice value ranges from 19 to -19. * ** num_threads Number of threads in this process. * *** starttime The time in jiffies the process started after system boot. * **** vsize Virtual memory size in bytes. * ** rss Resident Set Size: number of pages the process has in real memory, minus 3 for administrative purposes. This is just the pages which count towards text, data, or stack space. This does not include pages which have not been demand-loaded in, or which are swapped out. * *** signal The bitmap of pending signals. * *** blocked The bitmap of blocked signals. * *** sigignore The bitmap of ignored signals. * *** sigcatch The bitmap of caught signals. * ** policy Scheduling policy (see sched_setscheduler(2)). File /proc//statm * ** resident resident set size * *** size total program size * *** text text (code) Other Per-PID Files * ** /proc//cwd * ** /proc//exe * ** /proc//environ Non Per-PID Files * ** /proc/version File /proc//stat * **** rlim Current limit in bytes on the rss of the process (usually 4294967295 on i386). * **** startcode The address above which program text can run. * **** endcode The address below which program text can run. * **** startstack The address of the start of the stack. * **** kstkesp The current value of esp (stack pointer), as found in the kernel stack page for the process. * **** kstkeip The current EIP (instruction pointer). * **** exit_signal Signal to be sent to parent when we die. File /proc//statm * **** share shared pages * **** data data/stack Other Per-PID File * **** /proc//root Non Per-PID Files * **** /proc/stat * **** /proc/meminfo File /proc//stat * ***** wchan This is the "channel" in which the process is waiting. It is the address of a system call, and can be looked up in a namelist if you need a textual name. (If you have an up-to-date /etc/psdatabase, * ***** processor CPU number last executed on. * ***** rt_priority Real-time scheduling priority * ***** delayacct_blkio_ticks Aggregated block I/O delays, measured in clock ticks (centiseconds). * ***** flags PF_* fields defined in * ~~~~~ itrealvalue The time in jiffies before the next SIGALRM is sent to the process due to an interval timer. * ~~~~~ nswap Number of pages swapped (not maintained). * ~~~~~ cnswap Cumulative nswap for child processes (not maintained). File /proc//statm * ~~~~~ lib library (not required) * ~~~~~ dt dirty pages (not required) ------ Code Updates ---- 1. May, 14, 2008 2. May, 18, 2008 3. May, 28, 2008 4. June, 1, 2008 5. June, 2, 2008 6. June, 4, 2008 7. June, 5, 2008 (3 commits, 00:30 HRS, 02:30 HRS, 11:15HRS, all in IST) 8. June, 9, 2008 9. June, 19, 2008 (Targets 1 and 2 successfully accomplished. Duration between the commits became inevitably longer because of the large amount of time spent on debugging the code.) ------ Contact Details ---- Name : Madhusudan.C.S Email : [madhusudancs@gmail.com](mailto:madhusudancs@gmail.com) Blog : [http://www.madhusudancs.info](http://www.madhusudancs.info/) Detailed proposal: [http://www.madhusudancs.info/gnu-hurd-procfs-proposal](http://www.madhusudancs.info/gnu-hurd-procfs-proposal) Google Summer of Code Site Link: [Abstract](http://code.google.com/soc/2008/hurd/appinfo.html?csaid=D2E9266819D2EEF9)