mirror of
https://github.com/genodelabs/genode.git
synced 2024-12-28 09:38:53 +00:00
735abca1b6
The link dissolve timeout is updated for every packet, which leads to trigger_once() RPCs that only marginally change the scheduled timeout but significantly slow down the packet throughput. genodelabs/genode#4555
346 lines
10 KiB
C++
346 lines
10 KiB
C++
/*
|
|
* \brief Connection to timer service and timeout scheduler
|
|
* \author Norman Feske
|
|
* \date 2008-08-22
|
|
*/
|
|
|
|
/*
|
|
* Copyright (C) 2008-2017 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__TIMER_SESSION__CONNECTION_H_
|
|
#define _INCLUDE__TIMER_SESSION__CONNECTION_H_
|
|
|
|
/* Genode includes */
|
|
#include <timer_session/client.h>
|
|
#include <base/connection.h>
|
|
#include <util/reconstructible.h>
|
|
#include <base/entrypoint.h>
|
|
#include <timer/timeout.h>
|
|
#include <trace/timestamp.h>
|
|
|
|
namespace Timer
|
|
{
|
|
class Connection;
|
|
template <typename> class Periodic_timeout;
|
|
template <typename> class One_shot_timeout;
|
|
}
|
|
|
|
|
|
/**
|
|
* Periodic timeout that is linked to a custom handler, scheduled when constructed
|
|
*/
|
|
template <typename HANDLER>
|
|
struct Timer::Periodic_timeout : private Genode::Noncopyable,
|
|
private Genode::Timeout_handler
|
|
{
|
|
private:
|
|
|
|
using Duration = Genode::Duration;
|
|
using Timeout = Genode::Timeout;
|
|
using Microseconds = Genode::Microseconds;
|
|
|
|
typedef void (HANDLER::*Handler_method)(Duration);
|
|
|
|
Timeout _timeout;
|
|
HANDLER &_object;
|
|
Handler_method const _method;
|
|
|
|
|
|
/*********************
|
|
** Timeout_handler **
|
|
*********************/
|
|
|
|
void handle_timeout(Duration curr_time) override {
|
|
(_object.*_method)(curr_time); }
|
|
|
|
public:
|
|
|
|
Periodic_timeout(Connection &timer,
|
|
HANDLER &object,
|
|
Handler_method method,
|
|
Microseconds duration)
|
|
:
|
|
_timeout { timer },
|
|
_object { object },
|
|
_method { method }
|
|
{
|
|
_timeout.schedule_periodic(duration, *this);
|
|
}
|
|
};
|
|
|
|
|
|
/**
|
|
* One-shot timeout that is linked to a custom handler, scheduled manually
|
|
*/
|
|
template <typename HANDLER>
|
|
class Timer::One_shot_timeout : private Genode::Noncopyable,
|
|
private Genode::Timeout_handler
|
|
{
|
|
private:
|
|
|
|
using Duration = Genode::Duration;
|
|
using Timeout = Genode::Timeout;
|
|
using Microseconds = Genode::Microseconds;
|
|
|
|
typedef void (HANDLER::*Handler_method)(Duration);
|
|
|
|
Timeout _timeout;
|
|
HANDLER &_object;
|
|
Handler_method const _method;
|
|
|
|
|
|
/*********************
|
|
** Timeout_handler **
|
|
*********************/
|
|
|
|
void handle_timeout(Duration curr_time) override {
|
|
(_object.*_method)(curr_time); }
|
|
|
|
public:
|
|
|
|
One_shot_timeout(Connection &timer,
|
|
HANDLER &object,
|
|
Handler_method method)
|
|
:
|
|
_timeout { timer },
|
|
_object { object },
|
|
_method { method }
|
|
{ }
|
|
|
|
void schedule(Microseconds duration) {
|
|
_timeout.schedule_one_shot(duration, *this); }
|
|
|
|
void discard() { _timeout.discard(); }
|
|
|
|
bool scheduled() { return _timeout.scheduled(); }
|
|
|
|
Microseconds deadline() const { return _timeout.deadline(); }
|
|
};
|
|
|
|
|
|
/**
|
|
* Connection to timer service and timeout scheduler
|
|
*
|
|
* Multiplexes a timer session amongst different timeouts.
|
|
*/
|
|
class Timer::Connection : public Genode::Connection<Session>,
|
|
public Session_client,
|
|
private Genode::Time_source
|
|
{
|
|
friend class Genode::Timeout;
|
|
|
|
private:
|
|
|
|
using Timeout = Genode::Timeout;
|
|
using Timeout_handler = Genode::Timeout_handler;
|
|
using Timestamp = Genode::Trace::Timestamp;
|
|
using Duration = Genode::Duration;
|
|
using Mutex = Genode::Mutex;
|
|
using Microseconds = Genode::Microseconds;
|
|
using Milliseconds = Genode::Milliseconds;
|
|
using Entrypoint = Genode::Entrypoint;
|
|
using Io_signal_handler = Genode::Io_signal_handler<Connection>;
|
|
|
|
/*
|
|
* Noncopyable
|
|
*/
|
|
Connection(Connection const &);
|
|
Connection &operator = (Connection const &);
|
|
|
|
/*
|
|
* The mode determines which interface of the timer connection is
|
|
* enabled. Initially, a timer connection is in TIMER_SESSION mode.
|
|
* In this mode, the user can operate directly on the connection using
|
|
* the methods of the timer-session interface. As soon as the
|
|
* connection is handed over as argument to the constructor of a
|
|
* Periodic_timeout or a One_shot_timeout, it switches to
|
|
* TIMEOUT_FRAMEWORK mode. From this point on, the only method that
|
|
* the user can use directly on the connection is 'curr_time'. For
|
|
* the rest of the functionality he rather uses the interfaces of
|
|
* timeout objects that reference the connection.
|
|
*
|
|
* These are the characteristics of the two modes:
|
|
*
|
|
* TIMER_SESSION:
|
|
*
|
|
* * Allows for both blocking and non-blocking timeout semantics.
|
|
* * Missing local interpolation leads to less precise curr_time
|
|
* results.
|
|
* * Only one timeout at a time per connection.
|
|
*
|
|
* TIMEOUT FRAMEWORK:
|
|
*
|
|
* * Supports only non-blocking timeout semantics.
|
|
* * More precise curr_time results through local interpolation.
|
|
* * Multiplexing of multiple timeouts at the same connection
|
|
*/
|
|
enum Mode { TIMER_SESSION, TIMEOUT_FRAMEWORK };
|
|
|
|
Mode _mode { TIMER_SESSION };
|
|
Mutex _mutex { };
|
|
Genode::Signal_receiver _sig_rec { };
|
|
Genode::Signal_context _default_sigh_ctx { };
|
|
|
|
Genode::Signal_context_capability
|
|
_default_sigh_cap = _sig_rec.manage(&_default_sigh_ctx);
|
|
|
|
Genode::Signal_context_capability _custom_sigh_cap { };
|
|
|
|
void _sigh(Signal_context_capability sigh)
|
|
{
|
|
Session_client::sigh(sigh);
|
|
}
|
|
|
|
/****************************************************
|
|
** Members for interaction with Timeout framework **
|
|
****************************************************/
|
|
|
|
enum { MIN_TIMEOUT_US = 5000 };
|
|
enum { REAL_TIME_UPDATE_PERIOD_US = 500000 };
|
|
enum { MAX_INTERPOLATION_QUALITY = 3 };
|
|
enum { MAX_REMOTE_TIME_LATENCY_US = 500 };
|
|
enum { MAX_REMOTE_TIME_TRIALS = 5 };
|
|
enum { NR_OF_INITIAL_CALIBRATIONS = 3 * MAX_INTERPOLATION_QUALITY };
|
|
enum { MIN_FACTOR_LOG2 = 8 };
|
|
|
|
Io_signal_handler _signal_handler;
|
|
Timeout_handler *_handler { nullptr };
|
|
Mutex _real_time_mutex { };
|
|
uint64_t _us { elapsed_us() };
|
|
Timestamp _ts { _timestamp() };
|
|
Duration _real_time { Microseconds { _us } };
|
|
Duration _interpolated_time { _real_time };
|
|
unsigned _interpolation_quality { 0 };
|
|
uint64_t _us_to_ts_factor { 1 };
|
|
unsigned _us_to_ts_factor_shift { 0 };
|
|
Genode::Timeout_scheduler _timeout_scheduler { *this, Microseconds { 1 } };
|
|
|
|
Genode::Timeout_scheduler &_switch_to_timeout_framework_mode();
|
|
|
|
Timestamp _timestamp();
|
|
|
|
void _update_interpolation_quality(uint64_t min_factor,
|
|
uint64_t max_factor);
|
|
|
|
uint64_t _ts_to_us_ratio(Timestamp ts,
|
|
uint64_t us,
|
|
unsigned shift);
|
|
|
|
void _update_real_time();
|
|
|
|
Duration _update_interpolated_time(Duration &interpolated_time);
|
|
|
|
void _handle_timeout();
|
|
|
|
|
|
/*****************
|
|
** Time_source **
|
|
*****************/
|
|
|
|
void set_timeout(Microseconds duration, Timeout_handler &handler) override;
|
|
Microseconds max_timeout() const override { return Microseconds(REAL_TIME_UPDATE_PERIOD_US); }
|
|
|
|
public:
|
|
|
|
struct Method_cannot_be_used_in_timeout_framework_mode : Genode::Exception { };
|
|
|
|
/**
|
|
* Constructor
|
|
*
|
|
* \param env environment used for construction (e.g. quota trading)
|
|
* \param ep entrypoint used as timeout handler execution context
|
|
* \param label optional label used in session routing
|
|
*/
|
|
Connection(Genode::Env &env,
|
|
Genode::Entrypoint & ep,
|
|
char const *label = "");
|
|
|
|
/**
|
|
* Convenience constructor wrapper using the environment's entrypoint as
|
|
* timeout handler execution context
|
|
*/
|
|
Connection(Genode::Env &env, char const *label = "");
|
|
|
|
~Connection() { _sig_rec.dissolve(&_default_sigh_ctx); }
|
|
|
|
/*
|
|
* Intercept 'sigh' to keep track of customized signal handlers
|
|
*
|
|
* \noapi
|
|
* \deprecated Use One_shot_timeout (or Periodic_timeout) instead
|
|
*/
|
|
void sigh(Signal_context_capability sigh) override
|
|
{
|
|
if (_mode == TIMEOUT_FRAMEWORK) {
|
|
throw Method_cannot_be_used_in_timeout_framework_mode();
|
|
}
|
|
_custom_sigh_cap = sigh;
|
|
Session_client::sigh(_custom_sigh_cap);
|
|
}
|
|
|
|
/*
|
|
* Block for a time span of 'us' microseconds
|
|
*
|
|
* \noapi
|
|
* \deprecated Use One_shot_timeout (or Periodic_timeout) instead
|
|
*/
|
|
void usleep(uint64_t us) override
|
|
{
|
|
if (_mode == TIMEOUT_FRAMEWORK) {
|
|
throw Method_cannot_be_used_in_timeout_framework_mode();
|
|
}
|
|
/*
|
|
* Omit the interaction with the timer driver for the corner case
|
|
* of not sleeping at all. This corner case may be triggered when
|
|
* polling is combined with sleeping (as some device drivers do).
|
|
* If we passed the sleep operation to the timer driver, the
|
|
* timer would apply its policy about a minimum sleep time to
|
|
* the sleep operation, which is not desired when polling.
|
|
*/
|
|
if (us == 0)
|
|
return;
|
|
|
|
/* serialize sleep calls issued by different threads */
|
|
Mutex::Guard guard(_mutex);
|
|
|
|
/* temporarily install to the default signal handler */
|
|
if (_custom_sigh_cap.valid())
|
|
Session_client::sigh(_default_sigh_cap);
|
|
|
|
/* trigger timeout at default signal handler */
|
|
trigger_once(us);
|
|
_sig_rec.wait_for_signal();
|
|
|
|
/* revert custom signal handler if registered */
|
|
if (_custom_sigh_cap.valid())
|
|
Session_client::sigh(_custom_sigh_cap);
|
|
}
|
|
|
|
/*
|
|
* Block for a time span of 'ms' milliseconds
|
|
*
|
|
* \noapi
|
|
* \deprecated Use One_shot_timeout (or Periodic_timeout) instead
|
|
*/
|
|
void msleep(uint64_t ms) override
|
|
{
|
|
if (_mode == TIMEOUT_FRAMEWORK) {
|
|
throw Method_cannot_be_used_in_timeout_framework_mode();
|
|
}
|
|
usleep(1000*ms);
|
|
}
|
|
|
|
|
|
/*****************
|
|
** Time_source **
|
|
*****************/
|
|
|
|
Duration curr_time() override;
|
|
};
|
|
|
|
#endif /* _INCLUDE__TIMER_SESSION__CONNECTION_H_ */
|