summaryrefslogtreecommitdiff
path: root/microkernel/viengoos/projects
diff options
context:
space:
mode:
authorThomas Schwinge <thomas@codesourcery.com>2012-05-24 23:08:09 +0200
committerThomas Schwinge <thomas@codesourcery.com>2012-05-24 23:08:09 +0200
commit2910b7c5b1d55bc304344b584a25ea571a9075fb (patch)
treebfbfbc98d4c0e205d2726fa44170a16e8421855e /microkernel/viengoos/projects
parent35b719f54c96778f571984065579625bc9f15bf5 (diff)
Prepare toolchain/logs/master branch.
Diffstat (limited to 'microkernel/viengoos/projects')
-rw-r--r--microkernel/viengoos/projects/address_space_management.mdwn40
-rw-r--r--microkernel/viengoos/projects/capability-aware_compiler.mdwn16
-rw-r--r--microkernel/viengoos/projects/new_hash_function.mdwn22
3 files changed, 0 insertions, 78 deletions
diff --git a/microkernel/viengoos/projects/address_space_management.mdwn b/microkernel/viengoos/projects/address_space_management.mdwn
deleted file mode 100644
index 2d00e4f4..00000000
--- a/microkernel/viengoos/projects/address_space_management.mdwn
+++ /dev/null
@@ -1,40 +0,0 @@
-[[!meta copyright="Copyright © 2008, 2009 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_viengoos]]
-
-In Viengoos, a process's address space is managed entirely in user
-space by the process itself. This creates two interesting problems:
-dealing with circular dependencies resulting from having to manage the
-address space data structures and accessing and manipulating the
-address space data structures.
-
-First, managing the address space requires resources, which in turn
-may require address space (e.g., data structures require memory which
-require address space, etc.). We currently break this circular
-dependency by trying to keep enough resources in reserve that
-allocating resources for managing the address space never requires
-more resources than are minimally in the reserve. The reserve is
-currently chosen in an ad-hoc fashion. It would be nice to determine
-it more systematically. Moreover, it would be nice to reduce the
-cases in which a reserve is required. This may be possible by
-restructuring some of the code.
-
-Second, the address space data structures are protected using a single
-lock. This not only means that only a single thread can be updating
-the address space at a time, but that if a thread faults and the
-address space is locked, then the process dead locks! It should be
-possible to at least walk the address space using lock-free
-techniques. This requires updating the address space construction
-code such that all addresses remain valid during any given
-manipulation. Second, to avoid the mentioned dead-lock problem, we
-try to ensure that accessing the data structures will never result in
-a fault. This means protecting the stack. An alternative approach is
-to use undo buffers.
diff --git a/microkernel/viengoos/projects/capability-aware_compiler.mdwn b/microkernel/viengoos/projects/capability-aware_compiler.mdwn
deleted file mode 100644
index b4e465d9..00000000
--- a/microkernel/viengoos/projects/capability-aware_compiler.mdwn
+++ /dev/null
@@ -1,16 +0,0 @@
-[[!meta copyright="Copyright © 2008, 2009 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_viengoos]]
-
-Modify, e.g., gcc to understand capability semantics and teach gcc how
-to optimize it, e.g., how to batch and combine calls.
-
-This project is deemed suitable for a thesis.
diff --git a/microkernel/viengoos/projects/new_hash_function.mdwn b/microkernel/viengoos/projects/new_hash_function.mdwn
deleted file mode 100644
index d0374720..00000000
--- a/microkernel/viengoos/projects/new_hash_function.mdwn
+++ /dev/null
@@ -1,22 +0,0 @@
-[[!meta copyright="Copyright © 2008, 2009, 2010 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_viengoos]]
-
-The current hash function in libhurd-ihash results in a lot of
-collisions when the hash table is 80% full. To overcome this, we keep
-hash tables at most 30% full. This represents a fair amount of
-overhead. Find a better algorithm. There can either be one that is
-appropriate in the general case or one that works well in a relevant,
-specific case, e.g., viengoos/object.c uses a hash to find the object
-corresponding to a frame, which is keyed on its physical address.
-
-Note that this applies to the Hurd's [[hurd/libihash]], too.