diff options
Diffstat (limited to 'hurd')
| -rw-r--r-- | hurd/console.mdwn | 85 | ||||
| -rw-r--r-- | hurd/dde/guide.mdwn | 2 | ||||
| -rw-r--r-- | hurd/debugging/rpctrace.mdwn | 37 | ||||
| -rw-r--r-- | hurd/io_path.mdwn | 6 | ||||
| -rw-r--r-- | hurd/libpager.mdwn | 16 | ||||
| -rw-r--r-- | hurd/libports.mdwn | 19 | ||||
| -rw-r--r-- | hurd/libthreads.mdwn | 28 | ||||
| -rw-r--r-- | hurd/running/gnu/universal_package_manager.mdwn | 1 | ||||
| -rw-r--r-- | hurd/translator.mdwn | 1 | ||||
| -rw-r--r-- | hurd/translator/hello.mdwn | 14 | ||||
| -rw-r--r-- | hurd/translator/tmpfs/tmpfs_vs_defpager.mdwn | 37 | ||||
| -rw-r--r-- | hurd/virtual_file_system/discussion.mdwn | 39 |
12 files changed, 277 insertions, 8 deletions
diff --git a/hurd/console.mdwn b/hurd/console.mdwn index 4f976efd..f7230011 100644 --- a/hurd/console.mdwn +++ b/hurd/console.mdwn @@ -1,3 +1,88 @@ +[[!meta copyright="Copyright © 2002, 2003, 2004, 2005, 2006, 2007, 2009, 2011 +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]]."]]"""]] + +The Hurd console's implementation is broken into two pieces each running on +it's own process, the console client and server. + +The console client is also split into modules (input driver, display driver, +speaker, ...) but they all run in the same process. + +The console server puts itself as a translator on top of `/dev/vcs` folder +presenting the following hierarchy: + + + /dev/vcs + \ + +- 1 + \ + +- console + +- input + +- display + +- .. + +- n + +where the numbered nodes represent virtual consoles and their contents are all +alike. + +As the following graph shows, the console, input and display nodes are the +interfaces used by the terminal server, input driver and display drivers +respectively. + + +------------------+ +-----------------+ + | Input driver | | Terminal Server | + | | | | + | pc-kbd | | | + +------------------+ +-----------------+ + | _cons_vcons_input | + | writes to reads | + | vcs/i/input vcs/i/console | + | +-----------------+ | + | | Console Server | | + | | /hurd/console | | + | input_enqueue | --------------- | input_dequeue | + +--------------->| Input Queue |>---------------+ + | --------------- | + +--------------->| Output Buffer |>---------------+ + | +-----------------+ | + | | + | writes reads | + | vcs/i/console vcs/i/display | + | | + +----------------+ +-----------------+ + | Teminal Server | | Display driver | + | | | | + | /hurd/term | | vga | + +----------------+ +-----------------+ + +The input driver takes scancodes from the in-kernel kbd queue, translates them +into characters and writes them to the input node. Then the terminal server +reads the console node taking the characters out of the console server. + +Each of theese actions is actually an RPC handled by the translator on +`/dev/vcs`. Writes to input nodes are handled by calling `input_enqueue` to +put the character into a queue. And reads from console nodes are handled by +calling `input_dequeue` which takes out charecters from the queue and gives +them to the reader. + +It's important to note here that both `input_enqueue` and `input_dequeue` are +blocking operations and a blocked `input_dequeue` necessarily needs an +`input_enqueue` call to continue. + +[[RPC]]s are handled by the console server with the help of [[hurd/libports]]' +`ports_manage_multithreaded` API. + + +--- + +/!\ old content; [[!taglink open_issue_documentation]]: cleanup needed. + The below is a reworked version of Marcus Brinkmann's [letter to the debian-hurd list](http://lists.debian.org/debian-hurd/2002/debian-hurd-200209/msg00054.html). It describes how to setup the new console server for the Hurd. I am testing this right now, so this document is a work in progress. -- [[Main/JoachimNilsson]] - 21 Jan 2003 diff --git a/hurd/dde/guide.mdwn b/hurd/dde/guide.mdwn index a3c08754..6a83519c 100644 --- a/hurd/dde/guide.mdwn +++ b/hurd/dde/guide.mdwn @@ -1,4 +1,4 @@ -[[!meta copyright="Copyright © 2010,2011 Free Software Foundation, Inc."]] +[[!meta copyright="Copyright © 2010, 2011 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 diff --git a/hurd/debugging/rpctrace.mdwn b/hurd/debugging/rpctrace.mdwn index f7136056..fd24f081 100644 --- a/hurd/debugging/rpctrace.mdwn +++ b/hurd/debugging/rpctrace.mdwn @@ -52,6 +52,43 @@ See `rpctrace --help` about how to use it. <antrik> note that there is a number of known bugs in rpctrace, for which zhengda has sent patches... though I haven't reviewed all of them I think <antrik> there are some nasty Mach operations that are really hard to proxy -- but I don't think the auth mechanism needs any of these... +* IRC, freenode, #hurd, 2011-11-04 + + [[!taglink open_issue_documentation]] + + <mcsim> hello. Are there any documentation about understanding output + of rpctrace? + <braunr> no + <braunr> you should read the source code, best doc available + <braunr> if you have too many numbers and almost no symbolc names, + you're lacking rpc definition lists + <braunr> check that the gnumach-common package is installed, as it + provides the gnumach definitions + <braunr> (the glibc ones are almost always available) + <braunr> with those two, you should be fine for the beginning + <mcsim> gnumach-common is installed. And what is the name for glibc + package for gnumach definitions. + <mcsim> Also I'm using libraries specified by LD_LIBRARY_PATH. Does it + make influence on absence of symbolic names? + <braunr> no + <braunr> rpctrace --help + <braunr> see the --rpc-list=FILE option + <braunr> the default lists are in /usr/share/msgids/, with the .msgids + extension + <braunr> $ dpkg -S msgids + <braunr> gnumach-common: /usr/share/msgids/gnumach.msgids + <braunr> hurd: /usr/share/msgids/hurd.msgids + <braunr> ok, glibc has none, it's the hurd + <braunr> for more details about the output, read the source code + <braunr> it shouldn't be that hard to grasp + <mcsim> -I /usr/share/msgids helped + <mcsim> thank you + <braunr> it shouldn't have, it's the default path + <mcsim> but symbolic names appeared + <braunr> well, that's weird :) + <pinotree> braunr: the output of rpctrace --help should tell the + default dir for msgids + # See Also diff --git a/hurd/io_path.mdwn b/hurd/io_path.mdwn index 492edffe..c47b5dca 100644 --- a/hurd/io_path.mdwn +++ b/hurd/io_path.mdwn @@ -46,9 +46,9 @@ Back in `_Xio_read`. If the 2048 byte buffer is not decided to be used (out-of-line case or bigger than 2048 bytes case; server decides to instead provide a new memory region), -the [[`dealloc`|microkernel/mach/mig/dealloc]] flag is being set, which causes -Mach to unmap that memory region from the server's address space, i.e., doing a -memory *move* from the server to the client. +the [[`dealloc`|microkernel/mach/mig/documentation/dealloc]] flag is being set, +which causes Mach to unmap that memory region from the server's address space, +i.e., doing a memory *move* from the server to the client. Leave server-side RPC stub `_Xio_read`. diff --git a/hurd/libpager.mdwn b/hurd/libpager.mdwn index 99f28f2a..d844743d 100644 --- a/hurd/libpager.mdwn +++ b/hurd/libpager.mdwn @@ -1,4 +1,4 @@ -[[!meta copyright="Copyright © 2007, 2008, 2010 Free Software Foundation, +[[!meta copyright="Copyright © 2007, 2008, 2010, 2011 Free Software Foundation, Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable @@ -6,8 +6,8 @@ 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]]."]]"""]] +is included in the section entitled [[GNU Free Documentation +License|/fdl]]."]]"""]] Mach's [[microkernel/mach/external_pager_mechanism]]. @@ -16,6 +16,16 @@ Mach [[microkernel/mach/IPC]]'s [[microkernel/mach/ipc/sequence_numbering]]. [GNU Hurd Reference Manual: 4.2 Pager Library](http://www.gnu.org/software/hurd/doc/hurd_5.html#SEC32). + +# Writeback: Writing Out Dirty Pages + + +## Related + + * LWN, Jonathan Corbet, [*No-I/O dirty + throttling*](http://lwn.net/Articles/456904/), 2011-08-31. + + # Open Issues * [[open_issues/linux_vmsig]] diff --git a/hurd/libports.mdwn b/hurd/libports.mdwn index 28274338..6f2cd46d 100644 --- a/hurd/libports.mdwn +++ b/hurd/libports.mdwn @@ -1,4 +1,4 @@ -[[!meta copyright="Copyright © 2010 Free Software Foundation, Inc."]] +[[!meta copyright="Copyright © 2010, 2011 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 @@ -18,3 +18,20 @@ provide an interface independently of the underlying [[microkernel]]. *libports* does not itself depend on *[[libthreads]]*, but the appropriate threading hooks are used if present, that is if *[[libthreads]]* is used by another component. + + +# Message Processing + +## `ports_manage_multithreaded` + +When a message is recieved, the thread acting as receiver checks if any other +thread is also waiting for requests. If there is none, a new thread is +spawned. Thus, the current thread continues processing the message while the +newly created thread starts listening for new ones. ([[!taglink +open_issue_hurd]]: [[open_issues/multithreading]].) + +Also, there are configurable timeouts for [[translator]]s who want to go away +when they are not used. ([[!taglink open_issue_hurd]]: there used to be bugs +in this area, [[!message-id "87hev152we.fsf@becket.becket.net"]], but it may be +fixed as of [[!message-id "20111030210045.GA4983@myhost"]], +[[!GNU_Savannah_Git_hurd_hurd 9b5429e834cde56f73b8ff605e36afc7d9bb6e1b]].) diff --git a/hurd/libthreads.mdwn b/hurd/libthreads.mdwn new file mode 100644 index 00000000..8b1a97e6 --- /dev/null +++ b/hurd/libthreads.mdwn @@ -0,0 +1,28 @@ +[[!meta copyright="Copyright © 2011 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]]."]]"""]] + +`libthreads` a.k.a. C threads. + + +# Internals + + +## Threads' Death + +C threads death doesn't actually free the thread's stack (and maybe not the +associated Mach ports either). That's because there's no way to free the stack +after the thread dies (because the thread of control is gone); the stack needs +to be freed by something else, and there's nothing convenient to do it. There +are many ways to make it work. + +However, it isn't really a leak, because the unfreed resources do get used for +the next thread. So the issue is that the shrinkage of resource consumption +never happens, but it doesn't grow without bounds; it just stays at the maximum +even if the current number of threads is lower. diff --git a/hurd/running/gnu/universal_package_manager.mdwn b/hurd/running/gnu/universal_package_manager.mdwn index 58841b02..bf1b92e0 100644 --- a/hurd/running/gnu/universal_package_manager.mdwn +++ b/hurd/running/gnu/universal_package_manager.mdwn @@ -155,3 +155,4 @@ To join the project just list your name below. 8. Abhradip Mukherjee 9. Ermenegildo Fiorito 10. Oltion Doda + 11. Russell James diff --git a/hurd/translator.mdwn b/hurd/translator.mdwn index bf7af3ce..3527267f 100644 --- a/hurd/translator.mdwn +++ b/hurd/translator.mdwn @@ -80,6 +80,7 @@ The [[concept|concepts]] of translators creates its own problems, too: # Existing Translators +* [[hello]] * [[auth]] * [[exec]] * [[pfinet]] diff --git a/hurd/translator/hello.mdwn b/hurd/translator/hello.mdwn new file mode 100644 index 00000000..bd56cd76 --- /dev/null +++ b/hurd/translator/hello.mdwn @@ -0,0 +1,14 @@ +[[!meta copyright="Copyright © 2011 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]]."]]"""]] + +The *hello* translator is an example of a simple [[libtrivfs]]-based one-node +[[translator]]. It is shipped as part of the [[Hurd source code +repository|source_repositories]], and exists in a single-threaded and a +multi-threaded variant. diff --git a/hurd/translator/tmpfs/tmpfs_vs_defpager.mdwn b/hurd/translator/tmpfs/tmpfs_vs_defpager.mdwn index a9317c21..5228515f 100644 --- a/hurd/translator/tmpfs/tmpfs_vs_defpager.mdwn +++ b/hurd/translator/tmpfs/tmpfs_vs_defpager.mdwn @@ -233,3 +233,40 @@ See also: [[open_issues/resource_management_problems/pagers]]. I have never looked at it. [[open_issues/mach-defpager_vs_defpager]]. + + +# IRC, freenode, #hurd, 2011-11-08 + + <mcsim> who else uses defpager besides tmpfs and kernel? + <braunr> normally, nothing directly + <mcsim> than why tmpfs should use defpager? + <braunr> it's its backend + <braunr> backign store rather + <braunr> the backing store of most file systems are partitions + <braunr> tmpfs has none, it uses the swap space + <mcsim> if we allocate memory for tmpfs using vm_allocate, will it be able + to use swap partition? + <braunr> it should + <braunr> vm_allocate just maps anonymous memory + <braunr> anonymous memory uses swap space as its backing store too + <braunr> but be aware that this part of the vm system is known to have + deficiencies + <braunr> which is why all mach based implementations have rewritten their + default pager + <mcsim> what kind of deficiencies? + <braunr> bugs + <braunr> and design issues, making anonymous memory fragmentation horrible + <antrik> mcsim: vm_allocate doesn't return a memory object; so it can't be + passed to clients for mmap() + <mcsim> antrik: I use vm_allocate in pager_read_page + <antrik> mcsim: well, that means that you have to actually implement a + pager yourself + <antrik> also, when the kernel asks the pager to write back some pages, it + expects the memory to become free. if you are "paging" to ordinary + anonymous memory, this doesn't happen; so I expect it to have a very bad + effect on system performance + <antrik> both can be avoided by just passing a real anonymous memory + object, i.e. one provided by the defpager + <antrik> only problem is that the current defpager implementation can't + really handle that... + <antrik> at least that's my understanding of the situation diff --git a/hurd/virtual_file_system/discussion.mdwn b/hurd/virtual_file_system/discussion.mdwn new file mode 100644 index 00000000..9e12d01e --- /dev/null +++ b/hurd/virtual_file_system/discussion.mdwn @@ -0,0 +1,39 @@ +[[!meta copyright="Copyright © 2011 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]]."]]"""]] + +[[!tag open_issue_documentation]] + +IRC, freenode, #hurd, 2011-11-12: + + <sea4ever> So hurd implements a 'transparent translator' somewhere which + just passes all IO calls to the posix IO I'm used to? (i.e. read, write, + open, close, etc.?) + <youpi> it's the normal way of operation + <youpi> glibc's read() doesn't do a system call, it always does an RPC to + the underlying translator + <youpi> be it ext2fs for /, or your foobarfs for your node + <sea4ever> Ok that makes sense. How does one program know which translator + it should refer to though? + <sea4ever> the read() call magically knows which process to invoke? + <youpi> the / translator is always known + <youpi> and then you ask /'s translator about /home, then /home/you, then + /home/you/foobar + <youpi> it tells you which other translator tyou have to contact + <youpi> that's on open + <sea4ever> It's a tree! Ok. + <youpi> the notion of fd is then simply knowing the translator + <sea4ever> Right. 'file descriptor' is now 'translator address descriptor' + maybe. + <youpi> it's glibc which knows about FDs, nothing else knows + <youpi> yes + <youpi> actually an RPC port, simply + <sea4ever> I want to try out the new RPC mechanism that mach implements + <youpi> err, which "new" RPC ? + <youpi> mach's RPCs are very old actually :) |