mirror of
https://github.com/matrix-construct/construct
synced 2024-11-26 00:32:35 +01:00
1452 lines
30 KiB
C++
1452 lines
30 KiB
C++
// Matrix Construct
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//
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// Copyright (C) Matrix Construct Developers, Authors & Contributors
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// Copyright (C) 2016-2018 Jason Volk <jason@zemos.net>
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//
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// Permission to use, copy, modify, and/or distribute this software for any
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// purpose with or without fee is hereby granted, provided that the above
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// copyright notice and this permission notice is present in all copies. The
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// full license for this software is available in the LICENSE file.
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#include <RB_INC_X86INTRIN_H
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#include <cxxabi.h>
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#include <ircd/asio.h>
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/// Internal context implementation
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///
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struct ircd::ctx::ctx
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:instance_list<ctx>
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{
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using error_code = boost::system::error_code;
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static uint64_t id_ctr; // monotonic
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uint64_t id; // Unique runtime ID
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const char *name; // User given name (optional)
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context::flags flags; // User given flags
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boost::asio::io_service::strand strand; // mutex/serializer
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boost::asio::steady_timer alarm; // acting semaphore (64B)
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boost::asio::yield_context *yc; // boost interface
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uintptr_t stack_base; // assigned when spawned
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size_t stack_max; // User given stack size
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int64_t notes; // norm: 0 = asleep; 1 = awake; inc by others; dec by self
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continuation *cont; // valid when asleep; invalid when awake
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ctx *adjoindre; // context waiting for this to join()
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microseconds awake; // monotonic counter
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list::node node; // node for ctx::list
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bool started() const { return stack_base != 0; }
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bool finished() const { return started() && yc == nullptr; }
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bool interruption_point(std::nothrow_t); // Check for interrupt (and clear flag)
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void interruption_point(); // throws interrupted
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bool wait(); // yield context to ios queue (returns on this resume)
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void jump(); // jump to context directly (returns on your resume)
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void wake(); // jump to context by queueing with ios (use note())
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bool note(); // properly request wake()
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void operator()(boost::asio::yield_context, const std::function<void ()>) noexcept;
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ctx(const char *const &name = "<noname>",
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const size_t &stack_max = DEFAULT_STACK_SIZE,
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const context::flags &flags = (context::flags)0,
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boost::asio::io_service *const &ios = ircd::ios);
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ctx(ctx &&) = delete;
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ctx(const ctx &) = delete;
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ctx &operator=(ctx &&) = delete;
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ctx &operator=(const ctx &) = delete;
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};
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/// Instance list linkage for the list of all ctx instances.
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template<>
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decltype(ircd::util::instance_list<ircd::ctx::ctx>::list)
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ircd::util::instance_list<ircd::ctx::ctx>::list
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{};
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/// Public interface linkage for the list of all ctx instances
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decltype(ircd::ctx::ctxs)
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ircd::ctx::ctxs
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{
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ctx::ctx::list
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};
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/// Monotonic ctx id counter state. This counter is incremented for each
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/// newly created context.
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decltype(ircd::ctx::ctx::id_ctr)
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ircd::ctx::ctx::id_ctr
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{
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0
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};
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ircd::ctx::ctx::ctx(const char *const &name,
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const size_t &stack_max,
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const context::flags &flags,
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boost::asio::io_service *const &ios)
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:id{++id_ctr}
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,name{name}
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,flags{flags}
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,strand{*ios}
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,alarm{*ios}
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,yc{nullptr}
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,stack_base{0}
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,stack_max{stack_max}
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,notes{1}
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,cont{nullptr}
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,adjoindre{nullptr}
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,awake{0us}
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{
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}
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/// Base frame for a context.
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///
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/// This function is the first thing executed on the new context's stack
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/// and calls the user's function.
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void
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ircd::ctx::ctx::operator()(boost::asio::yield_context yc,
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const std::function<void ()> func)
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noexcept try
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{
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this->yc = &yc;
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notes = 1;
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stack_base = uintptr_t(__builtin_frame_address(0));
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ircd::ctx::current = this;
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mark(prof::event::CUR_ENTER);
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const unwind atexit([this]
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{
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mark(prof::event::CUR_LEAVE);
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if(adjoindre)
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notify(*adjoindre);
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ircd::ctx::current = nullptr;
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this->yc = nullptr;
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if(flags & context::DETACH)
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delete this;
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});
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// Check for a precocious interrupt
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if(unlikely(flags & context::INTERRUPTED))
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return;
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if(likely(bool(func)))
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func();
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}
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catch(const std::exception &e)
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{
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log::critical
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{
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"ctx(%p '%s' #%u): unhandled: %s",
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current,
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name,
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id,
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e.what()
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};
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// Preserving the stacktrace from the throw point here is hopeless.
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// We can terminate for developer nuisance but we will never know
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// where this exception came from and where it is going. Bottom line
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// is that #ifdef'ing away this handler or rethrowing isn't as useful as
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// handling the exception here with a log message and calling it a day.
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return;
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}
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/// Direct context switch to this context.
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///
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/// This currently doesn't work yet because the suspension state of this
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/// context has to be ready to be jumped to and that isn't implemented yet.
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void
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ircd::ctx::ctx::jump()
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{
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assert(this->yc);
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assert(current != this); // can't jump to self
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auto &yc(*this->yc);
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auto &target(*yc.coro_.lock());
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// Jump from the currently running context (source) to *this (target)
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// with continuation of source after target
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{
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current->notes = 0; // Unconditionally cleared here
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const continuation continuation{current};
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target();
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}
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assert(current != this);
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assert(current->notes == 1); // notes = 1; set by continuation dtor on wakeup
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interruption_point();
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}
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/// Yield (suspend) this context until notified.
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///
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/// This context must be currently running otherwise bad things. Returns false
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/// if the context was notified before actually suspending; the note is then
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/// considered handled an another attempt to `wait()` can be made. Returns true
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/// if the context suspended and was notified. When a context wakes up the
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/// note counter is reset.
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bool
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ircd::ctx::ctx::wait()
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{
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namespace errc = boost::system::errc;
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assert(this->yc);
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assert(current == this);
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if(--notes > 0)
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return false;
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const auto interruption{[this]
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(ctx *const &interruptor) noexcept
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{
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wake();
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}};
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boost::system::error_code ec;
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alarm.async_wait(boost::asio::yield_context{to_asio{interruption}}[ec]);
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assert(ec == errc::operation_canceled || ec == errc::success);
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assert(current == this);
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assert(notes == 1); // notes = 1; set by continuation dtor on wakeup
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interruption_point();
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return true;
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}
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/// Notifies this context to resume (wake up from waiting).
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///
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/// Returns true if this note was the first note received by this context
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/// while it's been suspended or false if it's already been notified.
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bool
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ircd::ctx::ctx::note()
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{
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if(notes++ > 0)
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return false;
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wake();
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return true;
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}
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/// Wakes a context without a note (internal)
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void
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ircd::ctx::ctx::wake()
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try
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{
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alarm.cancel();
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}
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catch(const boost::system::system_error &e)
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{
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log::error
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{
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"ctx::wake(%p): %s", this, e.what()
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};
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}
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/// Throws if this context has been flagged for interruption and clears
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/// the flag.
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void
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ircd::ctx::ctx::interruption_point()
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{
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if(unlikely(interruption_point(std::nothrow)))
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throw interrupted("ctx(%p) '%s'", (const void *)this, name);
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}
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/// Returns true if this context has been flagged for interruption and
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/// clears the flag.
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bool
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ircd::ctx::ctx::interruption_point(std::nothrow_t)
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{
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// Interruption shouldn't be used for normal operation,
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// so please eat this branch misprediction.
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if(unlikely(flags & context::INTERRUPTED))
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{
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mark(prof::event::CUR_INTERRUPT);
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flags &= ~context::INTERRUPTED;
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return true;
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}
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else return false;
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}
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///////////////////////////////////////////////////////////////////////////////
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//
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// ctx/ctx.h
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//
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/// Yield to context `ctx`.
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///
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///
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void
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ircd::ctx::yield(ctx &ctx)
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{
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assert(current);
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//ctx.jump();
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// !!! TODO !!!
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// XXX: We can't jump directly to a context if it's waiting on its alarm, and
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// we don't know whether it's waiting on its alarm. We can add another flag to
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// inform us of that, but most contexts are usually waiting on their alarm anyway.
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//
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// Perhaps a better way to do this would be to centralize the alarms into a single
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// context with the sole job of waiting on a single alarm. Then it can schedule
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// things allowing for more direct jumps until all work is complete.
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// !!! TODO !!!
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notify(ctx);
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}
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/// Notifies `ctx` to wake up from another std::thread
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void
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ircd::ctx::notify(ctx &ctx,
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threadsafe_t)
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{
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signal(ctx, [&ctx]
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{
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notify(ctx);
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});
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}
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/// Notifies `ctx` to wake up. This will enqueue the resumption, not jump
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/// directly to `ctx`.
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bool
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ircd::ctx::notify(ctx &ctx)
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{
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return ctx.note();
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}
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/// Executes `func` sometime between executions of `ctx` with thread-safety
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/// so `func` and `ctx` are never executed concurrently no matter how many
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/// threads the io_service has available to execute events on.
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void
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ircd::ctx::signal(ctx &ctx,
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std::function<void ()> func)
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{
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ctx.strand.post(std::move(func));
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}
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/// Marks `ctx` for interruption and enqueues it for resumption to receive the
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/// interrupt which will be an exception coming out of the point where the
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/// `ctx` was yielding.
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void
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ircd::ctx::interrupt(ctx &ctx)
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{
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if(finished(ctx))
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return;
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if(interruption(ctx))
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return;
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ctx.flags |= context::INTERRUPTED;
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if(likely(&ctx != current && ctx.cont != nullptr))
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ctx.cont->interrupted(current);
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}
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/// started() && !finished() && !running
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bool
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ircd::ctx::waiting(const ctx &ctx)
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{
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return started(ctx) && !finished(ctx) && !running(ctx);
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}
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/// Indicates if `ctx` is the current ctx
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bool
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ircd::ctx::running(const ctx &ctx)
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{
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return &ctx == current;
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}
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/// Indicates if `ctx` was ever jumped to
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bool
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ircd::ctx::started(const ctx &ctx)
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{
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return ctx.started();
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}
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/// Indicates if the base frame for `ctx` returned
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bool
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ircd::ctx::finished(const ctx &ctx)
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{
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return ctx.finished();
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}
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/// Indicates if `ctx` was interrupted; does not clear the flag
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bool
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ircd::ctx::interruption(const ctx &c)
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{
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return c.flags & context::INTERRUPTED;
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}
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/// Returns the notification count for `ctx
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const int64_t &
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ircd::ctx::notes(const ctx &ctx)
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{
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return ctx.notes;
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}
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/// Returns the notification count for `ctx
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const size_t &
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ircd::ctx::stack_max(const ctx &ctx)
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{
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return ctx.stack_max;
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}
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/// Returns the developer's optional name literal for `ctx`
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ircd::string_view
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ircd::ctx::name(const ctx &ctx)
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{
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return ctx.name;
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}
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/// Returns a reference to unique ID for `ctx` (which will go away with `ctx`)
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const uint64_t &
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ircd::ctx::id(const ctx &ctx)
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{
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return ctx.id;
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}
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///////////////////////////////////////////////////////////////////////////////
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//
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// ctx/this_ctx.h
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//
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// set by the continuation object and the base frame.
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__thread ircd::ctx::ctx *
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ircd::ctx::current;
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/// Yield the currently running context until `time_point` ignoring notes
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void
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ircd::ctx::this_ctx::sleep_until(const std::chrono::steady_clock::time_point &tp)
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{
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while(!wait_until(tp, std::nothrow));
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}
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/// Yield the currently running context until notified or `time_point`.
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///
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/// Returns true if this function returned because `time_point` was hit or
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/// false because this context was notified.
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bool
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ircd::ctx::this_ctx::wait_until(const std::chrono::steady_clock::time_point &tp,
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const std::nothrow_t &)
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{
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auto &c(cur());
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c.alarm.expires_at(tp);
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c.wait(); // now you're yielding with portals
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return std::chrono::steady_clock::now() >= tp;
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}
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/// Yield the currently running context for `duration` or until notified.
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///
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/// Returns the duration remaining if notified, or <= 0 if suspended for
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/// the full duration, or unchanged if no suspend ever took place.
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std::chrono::microseconds
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ircd::ctx::this_ctx::wait(const std::chrono::microseconds &duration,
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const std::nothrow_t &)
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{
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auto &c(cur());
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c.alarm.expires_from_now(duration);
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c.wait(); // now you're yielding with portals
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const auto ret(c.alarm.expires_from_now());
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// return remaining duration.
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// this is > 0 if notified
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// this is unchanged if a note prevented any wait at all
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return std::chrono::duration_cast<std::chrono::microseconds>(ret);
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}
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/// Yield the currently running context until notified.
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void
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ircd::ctx::this_ctx::wait()
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{
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auto &c(cur());
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c.alarm.expires_at(std::chrono::steady_clock::time_point::max());
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c.wait(); // now you're yielding with portals
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}
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/// Post the currently running context to the event queue and then suspend to
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/// allow other contexts in the queue to run.
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///
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/// Until we have our own queue the ios queue makes no guarantees if the queue
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/// is FIFO or LIFO etc :-/ It is generally bad practice to use this function,
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/// as one should make the effort to devise a specific cooperative strategy for
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/// how context switching occurs rather than this coarse/brute technique.
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void
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ircd::ctx::this_ctx::yield()
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{
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bool done(false);
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const auto restore([&done, &me(cur())]
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{
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done = true;
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notify(me);
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});
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// All spurious notifications are ignored until `done`
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ios->post(restore); do
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{
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wait();
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}
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while(!done);
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}
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/// Throws interrupted if the currently running context was interrupted
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/// and clears the interrupt flag.
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void
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ircd::ctx::this_ctx::interruption_point()
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{
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return cur().interruption_point();
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}
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/// Returns true if the currently running context was interrupted and clears
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/// the interrupt flag.
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bool
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ircd::ctx::this_ctx::interruption_requested()
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{
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return interruption(cur());
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}
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/// Returns unique ID of currently running context
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const uint64_t &
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ircd::ctx::this_ctx::id()
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{
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static const uint64_t zero{0};
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return current? id(cur()) : zero;
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}
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/// Returns optional developer-given name for currently running context
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ircd::string_view
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ircd::ctx::this_ctx::name()
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{
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static const string_view nada{"*"};
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return current? name(cur()) : nada;
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}
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//
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// exception_handler
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//
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ircd::ctx::this_ctx::exception_handler::exception_handler()
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noexcept
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:std::exception_ptr{std::current_exception()}
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{
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assert(bool(*this));
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//assert(!std::uncaught_exceptions());
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__cxa_end_catch();
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// We don't yet support more levels of exceptions; after ending this
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// catch we can't still be in another one. This doesn't apply if we're
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// not on any ctx currently.
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assert(!current || !std::current_exception());
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}
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//
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// critical_assertion
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//
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namespace ircd::ctx
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{
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bool critical_asserted;
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}
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ircd::ctx::this_ctx::critical_assertion::critical_assertion()
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:theirs{critical_asserted}
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{
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critical_asserted = true;
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}
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ircd::ctx::this_ctx::critical_assertion::~critical_assertion()
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noexcept
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{
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assert(critical_asserted);
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critical_asserted = theirs;
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}
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///////////////////////////////////////////////////////////////////////////////
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//
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// ctx/continuation.h
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//
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//
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// continuation
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//
|
|
|
|
ircd::ctx::continuation::continuation(ctx *const &self)
|
|
:self{self}
|
|
{
|
|
mark(prof::event::CUR_YIELD);
|
|
assert(!critical_asserted);
|
|
assert(self != nullptr);
|
|
assert(self->notes <= 1);
|
|
|
|
// Note: Construct an instance of ctx::exception_handler to enable yielding
|
|
// in your catch block.
|
|
//
|
|
// GNU cxxabi uses a singly-linked forward list (aka the 'exception
|
|
// stack') for pending exception activities. Due to this limitation we
|
|
// cannot interleave _cxa_begin_catch() and __cxa_end_catch() by yielding
|
|
// the ircd::ctx in an exception handler.
|
|
assert(!std::current_exception());
|
|
//assert(!std::uncaught_exceptions());
|
|
|
|
self->cont = this;
|
|
ircd::ctx::current = nullptr;
|
|
}
|
|
|
|
ircd::ctx::continuation::~continuation()
|
|
noexcept
|
|
{
|
|
ircd::ctx::current = self;
|
|
self->notes = 1;
|
|
mark(prof::event::CUR_CONTINUE);
|
|
|
|
// self->continuation is not null'ed here; it remains an invalid
|
|
// pointer while the context is awake.
|
|
}
|
|
|
|
void
|
|
ircd::ctx::continuation::interrupted(ctx *const &interruptor)
|
|
noexcept
|
|
{
|
|
}
|
|
|
|
ircd::ctx::continuation::operator boost::asio::yield_context &()
|
|
{
|
|
return *self->yc;
|
|
}
|
|
|
|
ircd::ctx::continuation::operator const boost::asio::yield_context &()
|
|
const
|
|
{
|
|
return *self->yc;
|
|
}
|
|
|
|
//
|
|
// to_asio
|
|
//
|
|
|
|
void
|
|
ircd::ctx::to_asio::interrupted(ctx *const &interruptor)
|
|
noexcept
|
|
{
|
|
if(handler)
|
|
handler(interruptor);
|
|
}
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// ctx/context.h
|
|
//
|
|
|
|
namespace ircd::ctx
|
|
{
|
|
static void spawn(ctx *const c, context::function func);
|
|
}
|
|
|
|
void
|
|
ircd::ctx::spawn(ctx *const c,
|
|
context::function func)
|
|
{
|
|
const boost::coroutines::attributes attrs
|
|
{
|
|
c->stack_max,
|
|
boost::coroutines::stack_unwind
|
|
};
|
|
|
|
auto bound
|
|
{
|
|
std::bind(&ctx::operator(), c, ph::_1, std::move(func))
|
|
};
|
|
|
|
boost::asio::spawn(c->strand, std::move(bound), attrs);
|
|
}
|
|
|
|
ircd::ctx::context::context(const char *const &name,
|
|
const size_t &stack_sz,
|
|
const flags &flags,
|
|
function func)
|
|
:c{std::make_unique<ctx>(name, stack_sz, flags, ircd::ios)}
|
|
{
|
|
auto spawn
|
|
{
|
|
std::bind(&ircd::ctx::spawn, c.get(), std::move(func))
|
|
};
|
|
|
|
// The profiler is told about the spawn request here, not inside the closure
|
|
// which is probably the same event-slice as event::CUR_ENTER and not as useful.
|
|
mark(prof::event::SPAWN);
|
|
|
|
// When the user passes the DETACH flag we want to release the unique_ptr
|
|
// of the ctx if and only if that ctx is committed to freeing itself. Our
|
|
// commitment ends at the 180 of this function. If no exception was thrown
|
|
// we expect the context to be committed to entry. If the POST flag is
|
|
// supplied and it gets lost in the asio queue it will not be entered, and
|
|
// will not be able to free itself; that will leak.
|
|
const unwind::nominal release
|
|
{
|
|
[this, &flags]
|
|
{
|
|
if(flags & context::DETACH)
|
|
this->detach();
|
|
}
|
|
};
|
|
|
|
if(flags & POST)
|
|
{
|
|
ios->post(std::move(spawn));
|
|
return;
|
|
}
|
|
|
|
// The current context must be reasserted if spawn returns here
|
|
auto *const theirs(ircd::ctx::current);
|
|
const unwind recurrent([&theirs]
|
|
{
|
|
ircd::ctx::current = theirs;
|
|
});
|
|
|
|
if(flags & DISPATCH)
|
|
ios->dispatch(std::move(spawn));
|
|
else
|
|
spawn();
|
|
}
|
|
|
|
ircd::ctx::context::context(const char *const &name,
|
|
const size_t &stack_size,
|
|
function func,
|
|
const flags &flags)
|
|
:context
|
|
{
|
|
name, stack_size, flags, std::move(func)
|
|
}
|
|
{
|
|
}
|
|
|
|
ircd::ctx::context::context(const char *const &name,
|
|
const flags &flags,
|
|
function func)
|
|
:context
|
|
{
|
|
name, DEFAULT_STACK_SIZE, flags, std::move(func)
|
|
}
|
|
{
|
|
}
|
|
|
|
ircd::ctx::context::context(const char *const &name,
|
|
function func,
|
|
const flags &flags)
|
|
:context
|
|
{
|
|
name, DEFAULT_STACK_SIZE, flags, std::move(func)
|
|
}
|
|
{
|
|
}
|
|
|
|
ircd::ctx::context::context(function func,
|
|
const flags &flags)
|
|
:context
|
|
{
|
|
"<noname>", DEFAULT_STACK_SIZE, flags, std::move(func)
|
|
}
|
|
{
|
|
}
|
|
|
|
ircd::ctx::context::~context()
|
|
noexcept
|
|
{
|
|
if(!c)
|
|
return;
|
|
|
|
// Can't join to bare metal, only from within another context.
|
|
if(current)
|
|
{
|
|
interrupt();
|
|
join();
|
|
}
|
|
|
|
// because *this uses unique_ptr's, if we dtor the ircd::ctx from
|
|
// right here and ircd::ctx hasn't been entered yet because the user
|
|
// passed the POST flag, the ctx::spawn() is still sitting in the ios
|
|
// queue.
|
|
if(c && !started(*c))
|
|
{
|
|
c->flags |= context::DETACH;
|
|
c.release();
|
|
}
|
|
}
|
|
|
|
void
|
|
ircd::ctx::context::join()
|
|
{
|
|
if(joined())
|
|
return;
|
|
|
|
mark(prof::event::JOIN);
|
|
assert(bool(c));
|
|
assert(!c->adjoindre);
|
|
c->adjoindre = &cur(); // Set the target context to notify this context when it finishes
|
|
wait();
|
|
mark(prof::event::JOINED);
|
|
}
|
|
|
|
ircd::ctx::ctx *
|
|
ircd::ctx::context::detach()
|
|
{
|
|
assert(bool(c));
|
|
c->flags |= DETACH;
|
|
return c.release();
|
|
}
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// ctx_pool.h
|
|
//
|
|
|
|
ircd::ctx::pool::pool(const char *const &name,
|
|
const size_t &stack_size,
|
|
const size_t &size)
|
|
:name{name}
|
|
,stack_size{stack_size}
|
|
,running{0}
|
|
,working{0}
|
|
{
|
|
add(size);
|
|
}
|
|
|
|
ircd::ctx::pool::~pool()
|
|
noexcept
|
|
{
|
|
del(size());
|
|
}
|
|
|
|
void
|
|
ircd::ctx::pool::operator()(closure closure)
|
|
{
|
|
queue.push_back(std::move(closure));
|
|
dock.notify();
|
|
}
|
|
|
|
void
|
|
ircd::ctx::pool::del(const size_t &num)
|
|
{
|
|
const ssize_t requested(size() - num);
|
|
const size_t target(std::max(requested, ssize_t(0)));
|
|
while(ctxs.size() > target)
|
|
ctxs.pop_back();
|
|
}
|
|
|
|
void
|
|
ircd::ctx::pool::add(const size_t &num)
|
|
{
|
|
for(size_t i(0); i < num; ++i)
|
|
ctxs.emplace_back(name, stack_size, context::POST, std::bind(&pool::main, this));
|
|
}
|
|
|
|
void
|
|
ircd::ctx::pool::join()
|
|
{
|
|
del(size());
|
|
}
|
|
|
|
void
|
|
ircd::ctx::pool::interrupt()
|
|
{
|
|
for(auto &context : ctxs)
|
|
context.interrupt();
|
|
}
|
|
|
|
void
|
|
ircd::ctx::pool::main()
|
|
noexcept try
|
|
{
|
|
++running;
|
|
const unwind avail([this]
|
|
{
|
|
--running;
|
|
});
|
|
|
|
while(1)
|
|
next();
|
|
}
|
|
catch(const interrupted &e)
|
|
{
|
|
/*
|
|
log::debug
|
|
{
|
|
"pool(%p) ctx(%p): %s", this, &cur(), e.what()
|
|
};
|
|
*/
|
|
}
|
|
|
|
void
|
|
ircd::ctx::pool::next()
|
|
try
|
|
{
|
|
dock.wait([this]
|
|
{
|
|
return !queue.empty();
|
|
});
|
|
|
|
++working;
|
|
const unwind avail([this]
|
|
{
|
|
--working;
|
|
});
|
|
|
|
const auto func(std::move(queue.front()));
|
|
queue.pop_front();
|
|
func();
|
|
}
|
|
catch(const interrupted &e)
|
|
{
|
|
throw;
|
|
}
|
|
catch(const std::exception &e)
|
|
{
|
|
log::critical
|
|
{
|
|
"pool(%p) ctx(%p '%s' #%u): unhandled: %s",
|
|
this,
|
|
current,
|
|
ircd::ctx::name(cur()),
|
|
ircd::ctx::id(cur()),
|
|
e.what()
|
|
};
|
|
}
|
|
|
|
void
|
|
ircd::ctx::debug_stats(const pool &pool)
|
|
{
|
|
log::debug
|
|
{
|
|
"pool '%s' (stack size: %zu) total: %zu avail: %zu queued: %zu active: %zu pending: %zu",
|
|
pool.name,
|
|
pool.stack_size,
|
|
pool.size(),
|
|
pool.avail(),
|
|
pool.queued(),
|
|
pool.active(),
|
|
pool.pending()
|
|
};
|
|
}
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// ctx_prof.h
|
|
//
|
|
|
|
namespace ircd::ctx::prof
|
|
{
|
|
time_point cur_slice_start; // Time slice state
|
|
uint64_t cur_slice_rdtsc; // Time slice state
|
|
|
|
void check_stack();
|
|
void check_slice();
|
|
void slice_start();
|
|
|
|
void handle_cur_continue();
|
|
void handle_cur_yield();
|
|
void handle_cur_leave();
|
|
void handle_cur_enter();
|
|
}
|
|
|
|
struct ircd::ctx::prof::settings ircd::ctx::prof::settings
|
|
{
|
|
0.33, // stack_usage_warning at 1/3 engineering tolerance
|
|
0.50, // stack_usage_assertion at 1/2 engineering tolerance
|
|
|
|
50ms, // slice_warning at 1/20 slices per second
|
|
0us, // slice_interrupt unused until project more mature...
|
|
0us, // slice_assertion unused; warning sufficient for now...
|
|
};
|
|
|
|
#ifdef RB_DEBUG
|
|
void
|
|
ircd::ctx::prof::mark(const event &e)
|
|
{
|
|
switch(e)
|
|
{
|
|
case event::CUR_ENTER: handle_cur_enter(); break;
|
|
case event::CUR_LEAVE: handle_cur_leave(); break;
|
|
case event::CUR_YIELD: handle_cur_yield(); break;
|
|
case event::CUR_CONTINUE: handle_cur_continue(); break;
|
|
default: break;
|
|
}
|
|
}
|
|
#else
|
|
void
|
|
ircd::ctx::prof::mark(const event &e)
|
|
{
|
|
}
|
|
#endif
|
|
|
|
void
|
|
ircd::ctx::prof::handle_cur_enter()
|
|
{
|
|
slice_start();
|
|
}
|
|
|
|
void
|
|
ircd::ctx::prof::handle_cur_leave()
|
|
{
|
|
check_slice();
|
|
}
|
|
|
|
void
|
|
ircd::ctx::prof::handle_cur_yield()
|
|
{
|
|
check_stack();
|
|
check_slice();
|
|
}
|
|
|
|
void
|
|
ircd::ctx::prof::handle_cur_continue()
|
|
{
|
|
slice_start();
|
|
}
|
|
|
|
void
|
|
ircd::ctx::prof::slice_start()
|
|
{
|
|
cur_slice_rdtsc = __rdtsc();
|
|
cur_slice_start = steady_clock::now();
|
|
}
|
|
|
|
void
|
|
ircd::ctx::prof::check_slice()
|
|
{
|
|
const uint64_t now_rdtsc(__rdtsc());
|
|
const uint64_t rdtsc_usage(now_rdtsc - cur_slice_rdtsc);
|
|
|
|
const auto now_sc(steady_clock::now());
|
|
const auto time_usage(now_sc - cur_slice_start);
|
|
|
|
auto &c(cur());
|
|
c.awake += duration_cast<microseconds>(time_usage);
|
|
|
|
if(unlikely(settings.slice_warning > 0us && time_usage >= settings.slice_warning))
|
|
{
|
|
log::dwarning
|
|
{
|
|
"context timeslice exceeded '%s' #%lu total: %06ld$us last: %lu$ns %lu$tsc",
|
|
name(c),
|
|
id(c),
|
|
c.awake.count(),
|
|
duration_cast<nanoseconds>(time_usage).count(),
|
|
rdtsc_usage
|
|
};
|
|
|
|
assert(settings.slice_assertion == 0us || time_usage < settings.slice_assertion);
|
|
}
|
|
|
|
if(unlikely(settings.slice_interrupt > 0us && time_usage >= settings.slice_interrupt))
|
|
throw interrupted
|
|
{
|
|
"Time slice exceeded '%s' #%lu (last: %06ld microseconds)",
|
|
name(c),
|
|
id(c),
|
|
duration_cast<microseconds>(time_usage).count()
|
|
};
|
|
}
|
|
|
|
void
|
|
ircd::ctx::prof::check_stack()
|
|
{
|
|
auto &c(cur());
|
|
const double &stack_max(c.stack_max);
|
|
const auto stack_usage(stack_usage_here(c));
|
|
|
|
if(unlikely(stack_usage > stack_max * settings.stack_usage_warning))
|
|
{
|
|
log::dwarning
|
|
{
|
|
"context stack usage ctx '%s' #%lu used %zu of %zu bytes",
|
|
name(c),
|
|
id(c),
|
|
stack_usage,
|
|
c.stack_max
|
|
};
|
|
|
|
assert(stack_usage < c.stack_max * settings.stack_usage_assertion);
|
|
}
|
|
}
|
|
|
|
size_t
|
|
ircd::ctx::stack_usage_here()
|
|
{
|
|
assert(current);
|
|
return stack_usage_here(*current);
|
|
}
|
|
|
|
size_t
|
|
ircd::ctx::stack_usage_here(const ctx &ctx)
|
|
{
|
|
return ctx.stack_base - uintptr_t(__builtin_frame_address(0));
|
|
}
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// ctx_ole.h
|
|
//
|
|
|
|
namespace ircd::ctx::ole
|
|
{
|
|
using closure = std::function<void () noexcept>;
|
|
|
|
std::mutex mutex;
|
|
std::condition_variable cond;
|
|
std::deque<closure> queue;
|
|
bool interruption;
|
|
std::thread *thread;
|
|
|
|
closure pop();
|
|
void worker() noexcept;
|
|
void push(closure &&);
|
|
}
|
|
|
|
ircd::ctx::ole::init::init()
|
|
{
|
|
assert(!thread);
|
|
interruption = false;
|
|
}
|
|
|
|
ircd::ctx::ole::init::~init()
|
|
noexcept
|
|
{
|
|
if(!thread)
|
|
return;
|
|
|
|
mutex.lock();
|
|
interruption = true;
|
|
cond.notify_one();
|
|
mutex.unlock();
|
|
thread->join();
|
|
delete thread;
|
|
thread = nullptr;
|
|
}
|
|
|
|
void
|
|
ircd::ctx::ole::offload(const std::function<void ()> &func)
|
|
{
|
|
bool done(false);
|
|
auto *const context(current);
|
|
const auto kick([&context, &done]
|
|
{
|
|
done = true;
|
|
notify(*context);
|
|
});
|
|
|
|
std::exception_ptr eptr;
|
|
auto closure([&func, &eptr, &context, &kick]
|
|
() noexcept
|
|
{
|
|
try
|
|
{
|
|
func();
|
|
}
|
|
catch(...)
|
|
{
|
|
eptr = std::current_exception();
|
|
}
|
|
|
|
// To wake the context on the IRCd thread we give it the kick
|
|
signal(*context, kick);
|
|
});
|
|
|
|
push(std::move(closure)); do
|
|
{
|
|
wait();
|
|
}
|
|
while(!done);
|
|
|
|
if(eptr)
|
|
std::rethrow_exception(eptr);
|
|
}
|
|
|
|
void
|
|
ircd::ctx::ole::push(closure &&func)
|
|
{
|
|
if(unlikely(!thread))
|
|
thread = new std::thread(&worker);
|
|
|
|
const std::lock_guard<decltype(mutex)> lock(mutex);
|
|
queue.emplace_back(std::move(func));
|
|
cond.notify_one();
|
|
}
|
|
|
|
void
|
|
ircd::ctx::ole::worker()
|
|
noexcept try
|
|
{
|
|
while(1)
|
|
{
|
|
const auto func(pop());
|
|
func();
|
|
}
|
|
}
|
|
catch(const interrupted &)
|
|
{
|
|
return;
|
|
}
|
|
|
|
ircd::ctx::ole::closure
|
|
ircd::ctx::ole::pop()
|
|
{
|
|
std::unique_lock<decltype(mutex)> lock(mutex);
|
|
cond.wait(lock, []
|
|
{
|
|
if(!queue.empty())
|
|
return true;
|
|
|
|
if(unlikely(interruption))
|
|
throw interrupted();
|
|
|
|
return false;
|
|
});
|
|
|
|
auto c(std::move(queue.front()));
|
|
queue.pop_front();
|
|
return std::move(c);
|
|
}
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// ctx_list.h
|
|
//
|
|
|
|
void
|
|
ircd::ctx::list::remove(ctx *const &c)
|
|
{
|
|
assert(c);
|
|
|
|
if(c == head)
|
|
{
|
|
pop_front();
|
|
return;
|
|
}
|
|
|
|
if(c == tail)
|
|
{
|
|
pop_back();
|
|
return;
|
|
}
|
|
|
|
assert(next(c) && prev(c));
|
|
prev(next(c)) = prev(c);
|
|
next(prev(c)) = next(c);
|
|
next(c) = nullptr;
|
|
prev(c) = nullptr;
|
|
}
|
|
|
|
ircd::ctx::ctx *
|
|
ircd::ctx::list::pop_back()
|
|
{
|
|
const auto tail
|
|
{
|
|
this->tail
|
|
};
|
|
|
|
if(!tail)
|
|
return tail;
|
|
|
|
assert(!next(tail));
|
|
if(!prev(tail))
|
|
{
|
|
this->head = nullptr;
|
|
this->tail = nullptr;
|
|
} else {
|
|
assert(next(prev(tail)) == tail);
|
|
next(prev(tail)) = nullptr;
|
|
this->tail = prev(tail);
|
|
}
|
|
|
|
prev(tail) = nullptr;
|
|
next(tail) = nullptr;
|
|
return tail;
|
|
}
|
|
|
|
ircd::ctx::ctx *
|
|
ircd::ctx::list::pop_front()
|
|
{
|
|
const auto head
|
|
{
|
|
this->head
|
|
};
|
|
|
|
if(!head)
|
|
return head;
|
|
|
|
assert(!prev(head));
|
|
if(!next(head))
|
|
{
|
|
this->head = nullptr;
|
|
this->tail = nullptr;
|
|
} else {
|
|
assert(prev(next(head)) == head);
|
|
prev(next(head)) = nullptr;
|
|
this->head = next(head);
|
|
}
|
|
|
|
prev(head) = nullptr;
|
|
next(head) = nullptr;
|
|
return head;
|
|
}
|
|
|
|
void
|
|
ircd::ctx::list::push_front(ctx *const &c)
|
|
{
|
|
assert(next(c) == nullptr);
|
|
assert(prev(c) == nullptr);
|
|
|
|
if(!head)
|
|
{
|
|
head = c;
|
|
tail = c;
|
|
return;
|
|
}
|
|
|
|
assert(prev(head) == nullptr);
|
|
prev(head) = c;
|
|
next(c) = head;
|
|
head = c;
|
|
}
|
|
|
|
void
|
|
ircd::ctx::list::push_back(ctx *const &c)
|
|
{
|
|
assert(next(c) == nullptr);
|
|
assert(prev(c) == nullptr);
|
|
|
|
if(!tail)
|
|
{
|
|
assert(!head);
|
|
head = c;
|
|
tail = c;
|
|
return;
|
|
}
|
|
|
|
assert(next(tail) == nullptr);
|
|
next(tail) = c;
|
|
prev(c) = tail;
|
|
tail = c;
|
|
}
|
|
|
|
void
|
|
ircd::ctx::list::rfor_each(const std::function<void (ctx &)> &closure)
|
|
{
|
|
for(ctx *tail{this->tail}; tail; tail = prev(tail))
|
|
closure(*tail);
|
|
}
|
|
|
|
void
|
|
ircd::ctx::list::rfor_each(const std::function<void (const ctx &)> &closure)
|
|
const
|
|
{
|
|
for(const ctx *tail{this->tail}; tail; tail = prev(tail))
|
|
closure(*tail);
|
|
}
|
|
|
|
bool
|
|
ircd::ctx::list::rfor_each(const std::function<bool (ctx &)> &closure)
|
|
{
|
|
for(ctx *tail{this->tail}; tail; tail = prev(tail))
|
|
if(!closure(*tail))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
bool
|
|
ircd::ctx::list::rfor_each(const std::function<bool (const ctx &)> &closure)
|
|
const
|
|
{
|
|
for(const ctx *tail{this->tail}; tail; tail = prev(tail))
|
|
if(!closure(*tail))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
void
|
|
ircd::ctx::list::for_each(const std::function<void (ctx &)> &closure)
|
|
{
|
|
for(ctx *head{this->head}; head; head = next(head))
|
|
closure(*head);
|
|
}
|
|
|
|
void
|
|
ircd::ctx::list::for_each(const std::function<void (const ctx &)> &closure)
|
|
const
|
|
{
|
|
for(const ctx *head{this->head}; head; head = next(head))
|
|
closure(*head);
|
|
}
|
|
|
|
bool
|
|
ircd::ctx::list::for_each(const std::function<bool (ctx &)> &closure)
|
|
{
|
|
for(ctx *head{this->head}; head; head = next(head))
|
|
if(!closure(*head))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
bool
|
|
ircd::ctx::list::for_each(const std::function<bool (const ctx &)> &closure)
|
|
const
|
|
{
|
|
for(const ctx *head{this->head}; head; head = next(head))
|
|
if(!closure(*head))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
ircd::ctx::ctx *&
|
|
ircd::ctx::list::prev(ctx *const &c)
|
|
{
|
|
assert(c);
|
|
return c->node.prev;
|
|
}
|
|
|
|
ircd::ctx::ctx *&
|
|
ircd::ctx::list::next(ctx *const &c)
|
|
{
|
|
assert(c);
|
|
return c->node.next;
|
|
}
|
|
|
|
const ircd::ctx::ctx *const &
|
|
ircd::ctx::list::prev(const ctx *const &c)
|
|
{
|
|
assert(c);
|
|
const auto &node(c->node);
|
|
const ctx *const &ptr(node.prev);
|
|
return ptr;
|
|
}
|
|
|
|
const ircd::ctx::ctx *const &
|
|
ircd::ctx::list::next(const ctx *const &c)
|
|
{
|
|
assert(c);
|
|
const auto &node(c->node);
|
|
const ctx *const &ptr(node.next);
|
|
return ptr;
|
|
}
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// ircd/ios.h
|
|
//
|
|
|
|
void
|
|
ircd::post(std::function<void ()> function)
|
|
{
|
|
ircd::ios->post(std::move(function));
|
|
}
|
|
|
|
void
|
|
ircd::dispatch(std::function<void ()> function)
|
|
{
|
|
ircd::ios->dispatch(std::move(function));
|
|
}
|