genode/repos/libports
Norman Feske 1f4f119b1e Capability quota accounting and trading
This patch mirrors the accounting and trading scheme that Genode employs
for physical memory to the accounting of capability allocations.

Capability quotas must now be explicitly assigned to subsystems by
specifying a 'caps=<amount>' attribute to init's start nodes.
Analogously to RAM quotas, cap quotas can be traded between clients and
servers as part of the session protocol. The capability budget of each
component is maintained by the component's corresponding PD session at
core.

At the current stage, the accounting is applied to RPC capabilities,
signal-context capabilities, and dataspace capabilities. Capabilities
that are dynamically allocated via core's CPU and TRACE service are not
yet covered. Also, the capabilities allocated by resource multiplexers
outside of core (like nitpicker) must be accounted by the respective
servers, which is not covered yet.

If a component runs out of capabilities, core's PD service prints a
warning to the log. To observe the consumption of capabilities per
component in detail, the PD service is equipped with a diagnostic
mode, which can be enabled via the 'diag' attribute in the target
node of init's routing rules. E.g., the following route enables the
diagnostic mode for the PD session of the "timer" component:

  <default-route>
    <service name="PD" unscoped_label="timer">
      <parent diag="yes"/>
    </service>
    ...
  </default-route>

For subsystems based on a sub-init instance, init can be configured
to report the capability-quota information of its subsystems by
adding the attribute 'child_caps="yes"' to init's '<report>'
config node. Init's own capability quota can be reported by adding
the attribute 'init_caps="yes"'.

Fixes #2398
2017-05-31 13:16:06 +02:00
..
doc tool: remove deprecated 'make prepare' mechanism 2016-03-17 17:02:04 +01:00
include stdcxx: update to version 6.3.0 2017-05-31 13:15:50 +02:00
lib Turn posix lib into shared library 2017-05-31 13:16:02 +02:00
ports qt5: fix build errors with GCC 6 2017-05-31 13:15:51 +02:00
recipes Depot-archive recipes 2017-05-31 13:15:56 +02:00
run Capability quota accounting and trading 2017-05-31 13:16:06 +02:00
src Assign cap quotas in run scripts and recipes 2017-05-31 13:16:06 +02:00
README README update 2016-08-30 17:24:00 +02:00

This directory contains ports of popular 3rd-party software to Genode.


Usage
-----

The tool './tool/ports/prepare_port' in the toplevel directory automates the
task of downloading and preparing the library source codes. You can select
individual packages that have to be prepared by specifying their base names
(without the version number) as command-line argument. For example, the
following command prepares both the C library and the Freetype library:
! ./tool/ports/prepare_port libc freetype

To compile and link against 3rd-party libraries of the 'libports' repository,
you have to include the repository into the build process by appending it to the
'REPOSITORIES' declaration of your '<build-dir>/etc/build.conf' file.


Under the hood
--------------

For each library, there is a file contained in the 'libports/ports/'
subdirectory. The file is named after the library and contains the
library-specific rules for downloading the source code and installing header
files.


How does 'libports' relate to the other repositories?
-----------------------------------------------------

Most libraries hosted in the 'libports' repository expect a complete C library,
which is provided with the 'libc' package. Please do not forget to prepare the
libc package when using any of the other libports packages. The libc, in turn,
depends on the 'os' repository for its back end. Because the 'os' repository is
the home of the dynamic linker, libraries contained in 'libports' are safe to
assume the presence of the dynamic linker and, thus, should be built as shared
libraries.