genode/repos/os/src/init/service.h

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/*
* \brief Services as targeted by session routes
* \author Norman Feske
* \date 2017-03-03
*/
/*
* Copyright (C) 2017 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU Affero General Public License version 3.
*/
#ifndef _SRC__INIT__SERVICE_H_
#define _SRC__INIT__SERVICE_H_
/* Genode includes */
#include <base/service.h>
#include <base/child.h>
namespace Init {
class Abandonable;
class Parent_service;
class Routed_service;
class Forwarded_service;
}
Follow practices suggested by "Effective C++" The patch adjust the code of the base, base-<kernel>, and os repository. To adapt existing components to fix violations of the best practices suggested by "Effective C++" as reported by the -Weffc++ compiler argument. The changes follow the patterns outlined below: * A class with virtual functions can no longer publicly inherit base classed without a vtable. The inherited object may either be moved to a member variable, or inherited privately. The latter would be used for classes that inherit 'List::Element' or 'Avl_node'. In order to enable the 'List' and 'Avl_tree' to access the meta data, the 'List' must become a friend. * Instead of adding a virtual destructor to abstract base classes, we inherit the new 'Interface' class, which contains a virtual destructor. This way, single-line abstract base classes can stay as compact as they are now. The 'Interface' utility resides in base/include/util/interface.h. * With the new warnings enabled, all member variables must be explicitly initialized. Basic types may be initialized with '='. All other types are initialized with braces '{ ... }' or as class initializers. If basic types and non-basic types appear in a row, it is nice to only use the brace syntax (also for basic types) and align the braces. * If a class contains pointers as members, it must now also provide a copy constructor and assignment operator. In the most cases, one would make them private, effectively disallowing the objects to be copied. Unfortunately, this warning cannot be fixed be inheriting our existing 'Noncopyable' class (the compiler fails to detect that the inheriting class cannot be copied and still gives the error). For now, we have to manually add declarations for both the copy constructor and assignment operator as private class members. Those declarations should be prepended with a comment like this: /* * Noncopyable */ Thread(Thread const &); Thread &operator = (Thread const &); In the future, we should revisit these places and try to replace the pointers with references. In the presence of at least one reference member, the compiler would no longer implicitly generate a copy constructor. So we could remove the manual declaration. Issue #465
2017-12-21 15:42:15 +01:00
class Init::Abandonable : Interface
{
private:
bool _abandoned = false;
public:
void abandon() { _abandoned = true; }
bool abandoned() const { return _abandoned; }
};
class Init::Parent_service : public Genode::Parent_service, public Abandonable
{
private:
Registry<Parent_service>::Element _reg_elem;
public:
Parent_service(Registry<Parent_service> &registry, Env &env,
Service::Name const &name)
:
Genode::Parent_service(env, name), _reg_elem(registry, *this)
{ }
};
/**
* Init-specific representation of a child service
*/
class Init::Routed_service : public Async_service, public Abandonable
{
public:
typedef Child_policy::Name Child_name;
Follow practices suggested by "Effective C++" The patch adjust the code of the base, base-<kernel>, and os repository. To adapt existing components to fix violations of the best practices suggested by "Effective C++" as reported by the -Weffc++ compiler argument. The changes follow the patterns outlined below: * A class with virtual functions can no longer publicly inherit base classed without a vtable. The inherited object may either be moved to a member variable, or inherited privately. The latter would be used for classes that inherit 'List::Element' or 'Avl_node'. In order to enable the 'List' and 'Avl_tree' to access the meta data, the 'List' must become a friend. * Instead of adding a virtual destructor to abstract base classes, we inherit the new 'Interface' class, which contains a virtual destructor. This way, single-line abstract base classes can stay as compact as they are now. The 'Interface' utility resides in base/include/util/interface.h. * With the new warnings enabled, all member variables must be explicitly initialized. Basic types may be initialized with '='. All other types are initialized with braces '{ ... }' or as class initializers. If basic types and non-basic types appear in a row, it is nice to only use the brace syntax (also for basic types) and align the braces. * If a class contains pointers as members, it must now also provide a copy constructor and assignment operator. In the most cases, one would make them private, effectively disallowing the objects to be copied. Unfortunately, this warning cannot be fixed be inheriting our existing 'Noncopyable' class (the compiler fails to detect that the inheriting class cannot be copied and still gives the error). For now, we have to manually add declarations for both the copy constructor and assignment operator as private class members. Those declarations should be prepended with a comment like this: /* * Noncopyable */ Thread(Thread const &); Thread &operator = (Thread const &); In the future, we should revisit these places and try to replace the pointers with references. In the presence of at least one reference member, the compiler would no longer implicitly generate a copy constructor. So we could remove the manual declaration. Issue #465
2017-12-21 15:42:15 +01:00
struct Pd_accessor : Interface
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
2017-05-08 21:35:43 +02:00
{
virtual Pd_session &pd() = 0;
virtual Pd_session_capability pd_cap() const = 0;
};
struct Ram_accessor : Interface
{
virtual Pd_session &ram() = 0;
virtual Pd_session_capability ram_cap() const = 0;
};
private:
Child_name _child_name;
Pd_accessor &_pd_accessor;
Session_state::Factory &_factory;
Registry<Routed_service>::Element _registry_element;
public:
/**
* Constructor
*
* \param services registry of all services provides by children
* \param child_name child name of server, used for session routing
*
* The other arguments correspond to the arguments of 'Async_service'.
*/
Routed_service(Registry<Routed_service> &services,
Child_name const &child_name,
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
2017-05-08 21:35:43 +02:00
Pd_accessor &pd_accessor,
Ram_accessor &,
Id_space<Parent::Server> &server_id_space,
Session_state::Factory &factory,
Service::Name const &name,
Wakeup &wakeup)
:
Async_service(name, server_id_space, factory, wakeup),
_child_name(child_name), _pd_accessor(pd_accessor),
_factory(factory), _registry_element(services, *this)
{ }
Child_name const &child_name() const { return _child_name; }
Session_state::Factory &factory() { return _factory; }
/**
* Ram_transfer::Account interface
*/
void transfer(Pd_session_capability to, Ram_quota amount) override
{
if (to.valid()) _pd_accessor.pd().transfer_quota(to, amount);
}
/**
* Ram_transfer::Account interface
*/
Pd_session_capability cap(Ram_quota) const override
{
return _pd_accessor.pd_cap();
}
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
2017-05-08 21:35:43 +02:00
/**
* Cap_transfer::Account interface
*/
void transfer(Pd_session_capability to, Cap_quota amount) override
{
if (to.valid()) _pd_accessor.pd().transfer_quota(to, amount);
}
/**
* Cap_transfer::Account interface
*/
Pd_session_capability cap(Cap_quota) const override
{
return _pd_accessor.pd_cap();
}
};
#endif /* _SRC__INIT__SERVICE_H_ */