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/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/porting/guidelines.mdwn | 8 | ||||
| -rw-r--r-- | hurd/translator.mdwn | 1 | ||||
| -rw-r--r-- | hurd/translator/hello.mdwn | 14 |
9 files changed, 171 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/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/porting/guidelines.mdwn b/hurd/porting/guidelines.mdwn index efc8982a..03ce9e19 100644 --- a/hurd/porting/guidelines.mdwn +++ b/hurd/porting/guidelines.mdwn @@ -306,6 +306,14 @@ Not implemented, not POSIX. Try to disable the feature in the package. There is no programming interface for the parallel port on GNU/Hurd yet. +## <a name="cdrom"> <linux/cdrom.h> </a> + +Use <sys/cdrom.h> instead. + +## <a name="baud"> CBAUD </a> + +This is not actually standard; cfsetspeed, cfsetispeed, or cfsetospeed should be used instead. + ## <a name="errno"> `errno` values </a> When dealing with `errno`, you should always use the predefined error codes defined with the `E*` constants, instead of manually comparing/assigning/etc with their values. 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. |