mirror of
https://github.com/genodelabs/genode.git
synced 2024-12-22 15:02:25 +00:00
b3727a9b46
Issue #3159
356 lines
9.6 KiB
C++
356 lines
9.6 KiB
C++
/*
|
|
* \brief Child handling
|
|
* \author Norman Feske
|
|
* \date 2013-10-05
|
|
*/
|
|
|
|
/*
|
|
* Copyright (C) 2013-2017 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 _INCLUDE__CLI_MONITOR__CHILD_H_
|
|
#define _INCLUDE__CLI_MONITOR__CHILD_H_
|
|
|
|
/* Genode includes */
|
|
#include <util/list.h>
|
|
#include <base/registry.h>
|
|
#include <base/child.h>
|
|
#include <init/child_policy.h>
|
|
#include <os/child_policy_dynamic_rom.h>
|
|
#include <cpu_session/connection.h>
|
|
#include <pd_session/connection.h>
|
|
#include <base/session_label.h>
|
|
|
|
/* CLI-monitor includes */
|
|
#include <cli_monitor/ram.h>
|
|
|
|
namespace Cli_monitor { class Child_base; }
|
|
|
|
|
|
class Cli_monitor::Child_base : public Genode::Child_policy
|
|
{
|
|
public:
|
|
|
|
/*
|
|
* XXX derive donated quota from information to be provided by
|
|
* the used 'Connection' interfaces
|
|
*/
|
|
enum { DONATED_RAM_QUOTA = 128*1024 };
|
|
|
|
class Quota_exceeded : public Genode::Exception { };
|
|
|
|
typedef Genode::size_t size_t;
|
|
typedef Genode::Cap_quota Cap_quota;
|
|
|
|
typedef Genode::Registered<Genode::Parent_service> Parent_service;
|
|
|
|
private:
|
|
|
|
Genode::Env &_env;
|
|
|
|
Ram &_ram;
|
|
|
|
Genode::Allocator &_alloc;
|
|
|
|
Genode::Session_label const _label;
|
|
Binary_name const _binary_name;
|
|
|
|
Genode::Pd_session_capability _ref_pd_cap;
|
|
Genode::Pd_session &_ref_pd;
|
|
|
|
Cap_quota _cap_quota;
|
|
|
|
size_t _ram_quota;
|
|
size_t _ram_limit;
|
|
|
|
struct Parent_services : Genode::Registry<Parent_service>
|
|
{
|
|
Genode::Allocator &_alloc;
|
|
Parent_services(Genode::Allocator &alloc) : _alloc(alloc) { }
|
|
~Parent_services()
|
|
{
|
|
for_each([&] (Parent_service &s) { Genode::destroy(_alloc, &s); });
|
|
}
|
|
} _parent_services { _alloc };
|
|
|
|
enum { ENTRYPOINT_STACK_SIZE = 12*1024 };
|
|
Genode::Rpc_entrypoint _entrypoint;
|
|
|
|
Genode::Child_policy_dynamic_rom_file _config_policy;
|
|
|
|
/**
|
|
* If set to true, immediately withdraw resources yielded by the child
|
|
*/
|
|
bool _withdraw_on_yield_response = false;
|
|
|
|
/**
|
|
* Arguments of current resource request from the child
|
|
*/
|
|
Genode::Parent::Resource_args _resource_args { };
|
|
|
|
Genode::Signal_context_capability _yield_response_sigh_cap;
|
|
|
|
Genode::Signal_context_capability _exit_sig_cap;
|
|
|
|
/* true if child is scheduled for destruction */
|
|
bool _exited = false;
|
|
|
|
Genode::Child _child;
|
|
|
|
Genode::Service &_matching_service(Genode::Service::Name const &name,
|
|
Genode::Session_label const &label)
|
|
{
|
|
Genode::Service *service = nullptr;
|
|
|
|
/* check for config file request */
|
|
if ((service = _config_policy.resolve_session_request(name, label)))
|
|
return *service;
|
|
|
|
/* populate session-local parent service registry on demand */
|
|
_parent_services.for_each([&] (Parent_service &s) {
|
|
if (s.name() == name)
|
|
service = &s; });
|
|
|
|
if (service)
|
|
return *service;
|
|
|
|
return *new (_alloc) Parent_service(_parent_services, _env, name);
|
|
}
|
|
|
|
public:
|
|
|
|
/**
|
|
* Constructor
|
|
*
|
|
* \param ref_ram used as reference account for the child'd RAM
|
|
* session and for allocating the backing store
|
|
* for the child's configuration
|
|
* \param alloc allocator used to fill parent-service registry
|
|
* on demand
|
|
*/
|
|
Child_base(Genode::Env &env,
|
|
Ram &ram,
|
|
Genode::Allocator &alloc,
|
|
Name const &label,
|
|
Binary_name const &binary_name,
|
|
Genode::Pd_session &ref_pd,
|
|
Genode::Pd_session_capability ref_pd_cap,
|
|
Genode::Region_map &local_rm,
|
|
Cap_quota cap_quota,
|
|
Genode::size_t ram_quota,
|
|
Genode::size_t ram_limit,
|
|
Genode::Signal_context_capability yield_response_sig_cap,
|
|
Genode::Signal_context_capability exit_sig_cap)
|
|
:
|
|
_env(env), _ram(ram), _alloc(alloc),
|
|
_label(label), _binary_name(binary_name),
|
|
_ref_pd_cap (ref_pd_cap), _ref_pd (ref_pd),
|
|
_cap_quota(cap_quota), _ram_quota(ram_quota), _ram_limit(ram_limit),
|
|
_entrypoint(&ref_pd, ENTRYPOINT_STACK_SIZE, _label.string(), false),
|
|
_config_policy(local_rm, "config", _entrypoint, &_env.ram()),
|
|
_yield_response_sigh_cap(yield_response_sig_cap),
|
|
_exit_sig_cap(exit_sig_cap),
|
|
_child(local_rm, _entrypoint, *this)
|
|
{ }
|
|
|
|
Genode::Session_label label() const { return _label; }
|
|
|
|
void configure(char const *config, size_t config_len)
|
|
{
|
|
_config_policy.load(config, config_len);
|
|
}
|
|
|
|
void start()
|
|
{
|
|
_entrypoint.activate();
|
|
}
|
|
|
|
/**
|
|
* Issue yield request to the child
|
|
*/
|
|
void yield(size_t amount, bool greedy)
|
|
{
|
|
if (requested_ram_quota())
|
|
return; /* resource request in flight */
|
|
|
|
char buf[128];
|
|
Genode::snprintf(buf, sizeof(buf), "ram_quota=%ld", amount);
|
|
_withdraw_on_yield_response = greedy;
|
|
_child.yield(buf);
|
|
}
|
|
|
|
/**
|
|
* Return amount of RAM currently requested by the child
|
|
*/
|
|
size_t requested_ram_quota() const
|
|
{
|
|
return Genode::Arg_string::find_arg(_resource_args.string(), "ram_quota").ulong_value(0);
|
|
}
|
|
|
|
/**
|
|
* Withdraw quota from the child
|
|
*
|
|
* \throw Ram::Transfer_quota_failed
|
|
*/
|
|
void withdraw_ram_quota(size_t amount)
|
|
{
|
|
if (!amount)
|
|
return;
|
|
|
|
_ram.withdraw_from(_child.pd_session_cap(), amount);
|
|
_ram_quota -= amount;
|
|
}
|
|
|
|
/**
|
|
* Upgrade quota of child
|
|
*
|
|
* \throw Ram::Transfer_quota_failed
|
|
*/
|
|
void upgrade_ram_quota(size_t amount)
|
|
{
|
|
_ram.transfer_to(_child.pd_session_cap(), amount);
|
|
_ram_quota += amount;
|
|
|
|
/* wake up child if resource request is in flight */
|
|
size_t const req = requested_ram_quota();
|
|
if (req && _child.pd().avail_ram().value >= req) {
|
|
_child.notify_resource_avail();
|
|
|
|
/* clear request state */
|
|
_resource_args = Genode::Parent::Resource_args("");
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Try to respond to a current resource request issued by the child
|
|
*
|
|
* This method evaluates the conditions, under which a resource
|
|
* request can be answered: There must be enough room between the
|
|
* current quota and the configured limit, and there must be enough
|
|
* slack memory available. If both conditions are met, the quota
|
|
* of the child gets upgraded.
|
|
*/
|
|
void try_response_to_resource_request()
|
|
{
|
|
size_t const req = requested_ram_quota();
|
|
|
|
if (!req)
|
|
return; /* no resource request in flight */
|
|
|
|
/*
|
|
* Respond to the current request if the requested quota fits
|
|
* within the limit and if there is enough free quota available.
|
|
*/
|
|
if (req <= _ram.status().avail && req + _ram_quota <= _ram_limit) {
|
|
try { upgrade_ram_quota(req); }
|
|
catch (Ram::Transfer_quota_failed) { }
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Set limit for on-demand RAM quota expansion
|
|
*/
|
|
void ram_limit(size_t limit)
|
|
{
|
|
_ram_limit = limit;
|
|
try_response_to_resource_request();
|
|
}
|
|
|
|
struct Ram_status
|
|
{
|
|
size_t quota = 0, limit = 0, xfer = 0, used = 0, avail = 0, req = 0;
|
|
|
|
Ram_status() { }
|
|
Ram_status(size_t quota, size_t limit, size_t xfer, size_t used,
|
|
size_t avail, size_t req)
|
|
:
|
|
quota(quota), limit(limit), xfer(xfer), used(used),
|
|
avail(avail), req(req)
|
|
{ }
|
|
};
|
|
|
|
/**
|
|
* Return RAM quota status of the child
|
|
*
|
|
* XXX should be a const method, but the 'Pd_session' accessors
|
|
* are not const
|
|
*/
|
|
Ram_status ram_status()
|
|
{
|
|
return Ram_status(_ram_quota,
|
|
_ram_limit,
|
|
_ram_quota - _child.pd().ram_quota().value,
|
|
_child.pd().used_ram().value,
|
|
_child.pd().avail_ram().value,
|
|
requested_ram_quota());
|
|
}
|
|
|
|
/**
|
|
* Return true if child exited and should be destructed
|
|
*/
|
|
bool exited() const { return _exited; }
|
|
|
|
|
|
/****************************
|
|
** Child_policy interface **
|
|
****************************/
|
|
|
|
Name name() const override { return _label; }
|
|
Binary_name binary_name() const override { return _binary_name; }
|
|
|
|
Genode::Pd_session_capability ref_pd_cap() const override { return _ref_pd_cap; }
|
|
Genode::Pd_session &ref_pd() override { return _ref_pd; }
|
|
|
|
void init(Genode::Pd_session &session, Genode::Pd_session_capability cap) override
|
|
{
|
|
session.ref_account(_ref_pd_cap);
|
|
_ref_pd.transfer_quota(cap, _cap_quota);
|
|
_ref_pd.transfer_quota(cap, Genode::Ram_quota{_ram_quota});
|
|
}
|
|
|
|
Route resolve_session_request(Genode::Service::Name const &name,
|
|
Genode::Session_label const &label) override
|
|
{
|
|
return Route { .service = _matching_service(name, label),
|
|
.label = label,
|
|
.diag = Genode::Session::Diag() };
|
|
}
|
|
|
|
void yield_response() override
|
|
{
|
|
if (_withdraw_on_yield_response) {
|
|
enum { RESERVE = 4*1024*1024 };
|
|
|
|
size_t amount = _child.pd().avail_ram().value < RESERVE
|
|
? 0 : _child.pd().avail_ram().value - RESERVE;
|
|
|
|
/* try to immediately withdraw freed-up resources */
|
|
try { withdraw_ram_quota(amount); }
|
|
catch (Ram::Transfer_quota_failed) { }
|
|
}
|
|
|
|
/* propagate yield-response signal */
|
|
Genode::Signal_transmitter(_yield_response_sigh_cap).submit();
|
|
}
|
|
|
|
void resource_request(Genode::Parent::Resource_args const &args) override
|
|
{
|
|
_resource_args = args;
|
|
try_response_to_resource_request();
|
|
}
|
|
|
|
void exit(int exit_value) override
|
|
{
|
|
Genode::log("subsystem \"", name(), "\" exited with value ", exit_value);
|
|
_exited = true;
|
|
|
|
/* trigger destruction of the child */
|
|
Genode::Signal_transmitter(_exit_sig_cap).submit();
|
|
}
|
|
};
|
|
|
|
#endif /* _INCLUDE__CLI_MONITOR__CHILD_H_ */
|