Everywhere: Replace a bundle of dbg with dbgln.

These changes are arbitrarily divided into multiple commits to make it
easier to find potentially introduced bugs with git bisect.

This commit touches some dbg() calls which are enclosed in macros. This
should be fine because with the new constexpr stuff, we ensure that the
stuff actually compiles.

AK/Debug.h

@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2020, the SerenityOS developers.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+// FIXME: We could generate this file with CMake and configure.
+
+#ifdef PROCESS_DEBUG
+constexpr bool debug_process = true;
+#else
+constexpr bool debug_process = false;
+#endif
+
+#ifdef SCHEDULER_DEBUG
+constexpr bool debug_scheduler = true;
+#else
+constexpr bool debug_scheduler = false;
+#endif
+
+#ifdef SCHEDULER_RUNNABLE_DEBUG
+constexpr bool debug_scheduler_runnable = true;
+#else
+constexpr bool debug_scheduler_runnable = false;
+#endif
+
+#ifdef SHARED_BUFFER_DEBUG
+constexpr bool debug_shared_buffer = true;
+#else
+constexpr bool debug_shared_buffer = false;
+#endif
+
+#ifdef THREAD_DEBUG
+constexpr bool debug_thread = true;
+#else
+constexpr bool debug_thread = false;
+#endif
+
+#ifdef LOCK_DEBUG
+constexpr bool debug_lock = true;
+#else
+constexpr bool debug_lock = false;
+#endif
+
+#ifdef SIGNAL_DEBUG
+constexpr bool debug_signal = true;
+#else
+constexpr bool debug_signal = false;
+#endif

Kernel/Process.cpp

@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/Debug.h>
 #include <AK/Demangle.h>
 #include <AK/QuickSort.h>
 #include <AK/StdLibExtras.h>
@@ -355,9 +356,7 @@ Process::Process(RefPtr<Thread>& first_thread, const String& name, uid_t uid, gi
     , m_ppid(ppid)
     , m_wait_block_condition(*this)
 {
-#ifdef PROCESS_DEBUG
-    dbg() << "Created new process " << m_name << "(" << m_pid.value() << ")";
-#endif
+    dbgln<debug_process>("Created new process {}({})", m_name, m_pid.value());
 
     m_page_directory = PageDirectory::create_for_userspace(*this, fork_parent ? &fork_parent->page_directory().range_allocator() : nullptr);
 
@@ -620,9 +619,8 @@ bool Process::dump_perfcore()
 void Process::finalize()
 {
     ASSERT(Thread::current() == g_finalizer);
-#ifdef PROCESS_DEBUG
-    dbg() << "Finalizing process " << *this;
-#endif
+
+    dbgln<debug_process>("Finalizing process {}", *this);
 
     if (is_dumpable()) {
         if (m_should_dump_core)

Kernel/Scheduler.cpp

@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/Debug.h>
 #include <AK/QuickSort.h>
 #include <AK/ScopeGuard.h>
 #include <AK/TemporaryChange.h>
@@ -131,28 +132,46 @@ bool Scheduler::pick_next()
         // no longer want to schedule this thread. We can't wait until
         // Scheduler::enter_current because we don't want to allow it to
         // transition back to user mode.
-#ifdef SCHEDULER_DEBUG
-        dbg() << "Scheduler[" << Processor::current().id() << "]: Thread " << *current_thread << " is dying";
-#endif
+
+        if constexpr (debug_scheduler)
+            dbgln("Scheduler[{}]: Thread {} is dying", Processor::current().id(), *current_thread);
+
         current_thread->set_state(Thread::Dying);
     }
 
-#ifdef SCHEDULER_RUNNABLE_DEBUG
-    dbg() << "Scheduler[" << Processor::current().id() << "]: Non-runnables:";
-    Scheduler::for_each_nonrunnable([&](Thread& thread) -> IterationDecision {
-        if (thread.state() == Thread::Dying)
-            dbg() << "  " << String::format("%-12s", thread.state_string()) << " " << thread << " @ " << String::formatted("{:04x}:{:08x}", thread.tss().cs, thread.tss().eip) << " Finalizable: " << thread.is_finalizable();
-        else
-            dbg() << "  " << String::format("%-12s", thread.state_string()) << " " << thread << " @ " << String::formatted("{:04x}:{:08x}", thread.tss().cs, thread.tss().eip);
-        return IterationDecision::Continue;
-    });
+    if constexpr (debug_scheduler_runnable) {
+        dbgln("Scheduler[{}j]: Non-runnables:", Processor::current().id());
+        Scheduler::for_each_nonrunnable([&](Thread& thread) -> IterationDecision {
+            if (thread.state() == Thread::Dying) {
+                dbgln("  {:12} {} @ {:04x}:{:08x} Finalizable: {}",
+                    thread.state_string(),
+                    thread,
+                    thread.tss().cs,
+                    thread.tss().eip,
+                    thread.is_finalizable());
+            } else {
+                dbgln("  {:12} {} @ {:04x}:{:08x}",
+                    thread.state_string(),
+                    thread,
+                    thread.tss().cs,
+                    thread.tss().eip);
+            }
 
-    dbg() << "Scheduler[" << Processor::current().id() << "]: Runnables:";
-    Scheduler::for_each_runnable([](Thread& thread) -> IterationDecision {
-        dbg() << "  " << String::format("%3u", thread.effective_priority()) << "/" << String::format("%2u", thread.priority()) << " " << String::format("%-12s", thread.state_string()) << " " << thread << " @ " << String::formatted("{:04x}:{:08x}", thread.tss().cs, thread.tss().eip);
-        return IterationDecision::Continue;
-    });
-#endif
+            return IterationDecision::Continue;
+        });
+
+        dbgln("Scheduler[{}j]: Runnables:", Processor::current().id());
+        Scheduler::for_each_runnable([](Thread& thread) -> IterationDecision {
+            dbgln("  {:3}/{:2} {:12} @ {:04x}:{:08x}",
+                thread.effective_priority(),
+                thread.priority(),
+                thread.state_string(),
+                thread.tss().cs,
+                thread.tss().eip);
+
+            return IterationDecision::Continue;
+        });
+    }
 
     Thread* thread_to_schedule = nullptr;
 
@@ -181,9 +200,7 @@ bool Scheduler::pick_next()
         // but since we're still holding the scheduler lock we're still in a critical section
         critical.leave();
 
-#ifdef SCHEDULER_DEBUG
-        dbg() << "Processing pending donate to " << *thread_to_schedule << " reason=" << reason;
-#endif
+        dbgln<debug_scheduler>("Processing pending donate to {} reason={}", *thread_to_schedule, reason);
         return donate_to_and_switch(thread_to_schedule, reason);
     }
 
@@ -211,9 +228,12 @@ bool Scheduler::pick_next()
     if (!thread_to_schedule)
         thread_to_schedule = Processor::current().idle_thread();
 
-#ifdef SCHEDULER_DEBUG
-    dbg() << "Scheduler[" << Processor::current().id() << "]: Switch to " << *thread_to_schedule << " @ " << String::format("%04x:%08x", thread_to_schedule->tss().cs, thread_to_schedule->tss().eip);
-#endif
+    if constexpr (debug_scheduler) {
+        dbgln("Scheduler[{}]: Switch to {} @ {:04x}:{:08x}",
+            Processor::current().id(),
+            *thread_to_schedule,
+            thread_to_schedule->tss().cs, thread_to_schedule->tss().eip);
+    }
 
     // We need to leave our first critical section before switching context,
     // but since we're still holding the scheduler lock we're still in a critical section
@@ -234,9 +254,7 @@ bool Scheduler::yield()
     scheduler_data.m_pending_donate_reason = nullptr;
 
     auto current_thread = Thread::current();
-#ifdef SCHEDULER_DEBUG
-    dbg() << "Scheduler[" << proc.id() << "]: yielding thread " << *current_thread << " in_irq: " << proc.in_irq();
-#endif
+    dbgln<debug_scheduler>("Scheduler[{}]: yielding thread {} in_irq={}", proc.id(), *current_thread, proc.in_irq());
     ASSERT(current_thread != nullptr);
     if (proc.in_irq() || proc.in_critical()) {
         // If we're handling an IRQ we can't switch context, or we're in
@@ -248,9 +266,9 @@ bool Scheduler::yield()
 
     if (!Scheduler::pick_next())
         return false;
-#ifdef SCHEDULER_DEBUG
-    dbg() << "Scheduler[" << Processor::current().id() << "]: yield returns to thread " << *current_thread << " in_irq: " << Processor::current().in_irq();
-#endif
+
+    if constexpr (debug_scheduler)
+        dbgln("Scheduler[{}]: yield returns to thread {} in_irq={}", Processor::current().id(), *current_thread, Processor::current().in_irq());
     return true;
 }
 
@@ -266,9 +284,7 @@ bool Scheduler::donate_to_and_switch(Thread* beneficiary, [[maybe_unused]] const
         return Scheduler::yield();
 
     unsigned ticks_to_donate = min(ticks_left - 1, time_slice_for(*beneficiary));
-#ifdef SCHEDULER_DEBUG
-    dbg() << "Scheduler[" << proc.id() << "]: Donating " << ticks_to_donate << " ticks to " << *beneficiary << ", reason=" << reason;
-#endif
+    dbgln<debug_scheduler>("Scheduler[{}]: Donating {} ticks to {}, reason={}", proc.id(), ticks_to_donate, *beneficiary, reason);
     beneficiary->set_ticks_left(ticks_to_donate);
 
     return Scheduler::context_switch(beneficiary);

Kernel/SharedBuffer.cpp

@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/Debug.h>
 #include <AK/Singleton.h>
 #include <Kernel/Process.h>
 #include <Kernel/SharedBuffer.h>
@@ -155,13 +156,9 @@ void SharedBuffer::deref_for_process(Process& process)
             ASSERT(m_total_refs > 0);
             m_total_refs--;
             if (ref.count == 0) {
-#ifdef SHARED_BUFFER_DEBUG
-                dbg() << "Releasing shared buffer reference on " << m_shbuf_id << " of size " << size() << " by PID " << process.pid().value();
-#endif
+                dbgln<debug_shared_buffer>("Releasing shared buffer reference on {} of size {} by PID {}", m_shbuf_id, size(), process.pid().value());
                 process.deallocate_region(*ref.region.unsafe_ptr()); // TODO: Region needs to be RefCounted!
-#ifdef SHARED_BUFFER_DEBUG
-                dbg() << "Released shared buffer reference on " << m_shbuf_id << " of size " << size() << " by PID " << process.pid().value();
-#endif
+                dbgln<debug_shared_buffer>("Released shared buffer reference on {} of size {} by PID {}", m_shbuf_id, size(), process.pid().value());
                 sanity_check("deref_for_process");
                 destroy_if_unused();
                 return;
@@ -179,15 +176,11 @@ bool SharedBuffer::disown(ProcessID pid)
     for (size_t i = 0; i < m_refs.size(); ++i) {
         auto& ref = m_refs[i];
         if (ref.pid == pid) {
-#ifdef SHARED_BUFFER_DEBUG
-            dbg() << "Disowning shared buffer " << m_shbuf_id << " of size " << size() << " by PID " << pid.value();
-#endif
+            dbgln<debug_shared_buffer>("Disowning shared buffer {} of size {} by PID {}", m_shbuf_id, size(), pid.value());
             ASSERT(m_total_refs >= ref.count);
             m_total_refs -= ref.count;
             m_refs.unstable_take(i);
-#ifdef SHARED_BUFFER_DEBUG
-            dbg() << "Disowned shared buffer " << m_shbuf_id << " of size " << size() << " by PID " << pid.value();
-#endif
+            dbgln<debug_shared_buffer>("Disowned shared buffer {} of size {} by PID {}", m_shbuf_id, size(), pid.value());
             destroy_if_unused();
             break;
         }
@@ -201,9 +194,7 @@ void SharedBuffer::destroy_if_unused()
     LOCKER(shared_buffers().lock());
     sanity_check("destroy_if_unused");
     if (m_total_refs == 0) {
-#ifdef SHARED_BUFFER_DEBUG
-        dbg() << "Destroying unused SharedBuffer{" << this << "} id: " << m_shbuf_id;
-#endif
+        dbgln<debug_shared_buffer>("Destroying unused SharedBuffer({}) id={}", this, m_shbuf_id);
         auto count_before = shared_buffers().resource().size();
         shared_buffers().resource().remove(m_shbuf_id);
         ASSERT(count_before != shared_buffers().resource().size());

Kernel/SharedBuffer.h

@@ -26,6 +26,7 @@
 
 #pragma once
 
+#include <AK/Debug.h>
 #include <AK/OwnPtr.h>
 #include <AK/WeakPtr.h>
 #include <Kernel/VM/AnonymousVMObject.h>
@@ -52,16 +53,12 @@ public:
         : m_shbuf_id(id)
         , m_vmobject(move(vmobject))
     {
-#ifdef SHARED_BUFFER_DEBUG
-        dbg() << "Created shared buffer " << m_shbuf_id << " of size " << m_vmobject->size();
-#endif
+        dbgln<debug_shared_buffer>("Created shared buffer {} of size {}", m_shbuf_id, size());
     }
 
     ~SharedBuffer()
     {
-#ifdef SHARED_BUFFER_DEBUG
-        dbg() << "Destroyed shared buffer " << m_shbuf_id << " of size " << size();
-#endif
+        dbgln<debug_shared_buffer>("Destroyed shared buffer {} of size {}", m_shbuf_id, size());
     }
 
     void sanity_check(const char* what);

Kernel/Thread.cpp

@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/Debug.h>
 #include <AK/Demangle.h>
 #include <AK/ScopeGuard.h>
 #include <AK/StringBuilder.h>
@@ -61,9 +62,8 @@ Thread::Thread(NonnullRefPtr<Process> process)
     } else {
         m_tid = Process::allocate_pid().value();
     }
-#ifdef THREAD_DEBUG
-    dbg() << "Created new thread " << m_process->name() << "(" << m_process->pid().value() << ":" << m_tid.value() << ")";
-#endif
+    if constexpr (debug_thread)
+        dbgln("Created new thread {}({}:{})", m_process->name(), m_process->pid().value(), m_tid.value());
     set_default_signal_dispositions();
     m_fpu_state = (FPUState*)kmalloc_aligned<16>(sizeof(FPUState));
     reset_fpu_state();
@@ -182,9 +182,7 @@ void Thread::unblock(u8 signal)
 void Thread::set_should_die()
 {
     if (m_should_die) {
-#ifdef THREAD_DEBUG
-        dbg() << *this << " Should already die";
-#endif
+        dbgln("{} Should already die", *this);
         return;
     }
     ScopedCritical critical;
@@ -369,9 +367,7 @@ void Thread::finalize()
 
     {
         ScopedSpinLock lock(g_scheduler_lock);
-#ifdef THREAD_DEBUG
-        dbg() << "Finalizing thread " << *this;
-#endif
+        dbgln<debug_thread>("Finalizing thread {}", *this);
         set_state(Thread::State::Dead);
         m_join_condition.thread_finalizing();
     }
@@ -475,18 +471,16 @@ void Thread::send_signal(u8 signal, [[maybe_unused]] Process* sender)
 
     // FIXME: Figure out what to do for masked signals. Should we also ignore them here?
     if (should_ignore_signal(signal)) {
-#ifdef SIGNAL_DEBUG
-        dbg() << "Signal " << signal << " was ignored by " << process();
-#endif
+        dbgln<debug_signal>("Signal {} was ignored by {}", signal, process());
         return;
     }
 
-#ifdef SIGNAL_DEBUG
-    if (sender)
-        dbg() << "Signal: " << *sender << " sent " << signal << " to " << process();
-    else
-        dbg() << "Signal: Kernel sent " << signal << " to " << process();
-#endif
+    if constexpr (debug_signal) {
+        if (sender)
+            dbgln("Signal: {} sent {} to {}", *sender, signal, process());
+        else
+            dbgln("Signal: Kernel send {} to {}", signal, process());
+    }
 
     m_pending_signals |= 1 << (signal - 1);
     m_have_any_unmasked_pending_signals.store(pending_signals_for_state() & ~m_signal_mask, AK::memory_order_release);
@@ -494,16 +488,12 @@ void Thread::send_signal(u8 signal, [[maybe_unused]] Process* sender)
     if (m_state == Stopped) {
         ScopedSpinLock lock(m_lock);
         if (pending_signals_for_state()) {
-#ifdef SIGNAL_DEBUG
-            dbg() << "Signal: Resuming stopped " << *this << " to deliver signal " << signal;
-#endif
+            dbgln<debug_signal>("Signal: Resuming stopped {} to deliver signal {}", *this, signal);
             resume_from_stopped();
         }
     } else {
         ScopedSpinLock block_lock(m_block_lock);
-#ifdef SIGNAL_DEBUG
-        dbg() << "Signal: Unblocking " << *this << " to deliver signal " << signal;
-#endif
+        dbgln<debug_signal>("Signal: Unblocking {} to deliver signal {}", *this, signal);
         unblock(signal);
     }
 }
@@ -728,26 +718,20 @@ DispatchSignalResult Thread::dispatch_signal(u8 signal)
     auto& process = this->process();
     auto tracer = process.tracer();
     if (signal == SIGSTOP || (tracer && default_signal_action(signal) == DefaultSignalAction::DumpCore)) {
-#ifdef SIGNAL_DEBUG
-        dbg() << "signal: signal " << signal << " stopping thread " << *this;
-#endif
+        dbgln<debug_signal>("signal: signal {} sopping thread {}", signal, *this);
         set_state(State::Stopped, signal);
         return DispatchSignalResult::Yield;
     }
 
     if (signal == SIGCONT) {
-#ifdef SIGNAL_DEBUG
-        dbg() << "signal: SIGCONT resuming " << *this;
-#endif
+        dbgln("signal: SIGCONT resuming {}", *this);
     } else {
         if (tracer) {
             // when a thread is traced, it should be stopped whenever it receives a signal
             // the tracer is notified of this by using waitpid()
             // only "pending signals" from the tracer are sent to the tracee
             if (!tracer->has_pending_signal(signal)) {
-#ifdef SIGNAL_DEBUG
-                dbg() << "signal: " << signal << " stopping " << *this << " for tracer";
-#endif
+                dbgln("signal: {} stopping {} for tracer", signal, *this);
                 set_state(Stopped, signal);
                 return DispatchSignalResult::Yield;
             }
@@ -897,15 +881,13 @@ void Thread::set_state(State new_state, u8 stop_signal)
         if (previous_state == Invalid) {
             // If we were *just* created, we may have already pending signals
             if (has_unmasked_pending_signals()) {
-                dbgln("Dispatch pending signals to new thread {}", *this);
+                dbgln<debug_thread>("Dispatch pending signals to new thread {}", *this);
                 dispatch_one_pending_signal();
             }
         }
 
         m_state = new_state;
-#ifdef THREAD_DEBUG
-        dbg() << "Set Thread " << *this << " state to " << state_string();
-#endif
+        dbgln<debug_thread>("Set thread {} state to {}", *this, state_string());
     }
 
     if (m_process->pid() != 0) {
@@ -920,9 +902,7 @@ void Thread::set_state(State new_state, u8 stop_signal)
             process.for_each_thread([&](auto& thread) {
                 if (&thread == this || !thread.is_stopped())
                     return IterationDecision::Continue;
-#ifdef THREAD_DEBUG
-                dbg() << "Resuming peer thread " << thread;
-#endif
+                dbgln<debug_thread>("Resuming peer thread {}", thread);
                 thread.resume_from_stopped();
                 return IterationDecision::Continue;
             });
@@ -938,9 +918,7 @@ void Thread::set_state(State new_state, u8 stop_signal)
             process.for_each_thread([&](auto& thread) {
                 if (&thread == this || thread.is_stopped())
                     return IterationDecision::Continue;
-#ifdef THREAD_DEBUG
-                dbg() << "Stopping peer thread " << thread;
-#endif
+                dbgln<debug_thread>("Stopping peer thread {}", thread);
                 thread.set_state(Stopped, stop_signal);
                 return IterationDecision::Continue;
             });