Kernel+Profiler: Improve profiling subsystem

This turns the perfcore format into more a log than it was before,
which lets us properly log process, thread and region
creation/destruction. This also makes it unnecessary to dump the
process' regions every time it is scheduled like we did before.

Incidentally this also fixes 'profile -c' because we previously ended
up incorrectly dumping the parent's region map into the profile data.

Log-based mmap support enables profiling shared libraries which
are loaded at runtime, e.g. via dlopen().

This enables profiling both the parent and child process for
programs which use execve(). Previously we'd discard the profiling
data for the old process.

The Profiler tool has been updated to not treat thread IDs as
process IDs anymore. This enables support for processes with more
than one thread. Also, there's a new widget to filter which
process should be displayed.

1 files changed, 8 insertions, 4 deletions

diff --git a/Userland/DevTools/Profiler/SamplesModel.cpp b/Userland/DevTools/Profiler/SamplesModel.cpp
index b916061a1b..e46866e956 100644
--- a/Userland/DevTools/Profiler/SamplesModel.cpp
+++ b/Userland/DevTools/Profiler/SamplesModel.cpp
@@ -22,7 +22,7 @@ SamplesModel::~SamplesModel()
 
 int SamplesModel::row_count(const GUI::ModelIndex&) const
 {
-    return m_profile.filtered_event_count();
+    return m_profile.filtered_event_indices().size();
 }
 
 int SamplesModel::column_count(const GUI::ModelIndex&) const
@@ -37,6 +37,8 @@ String SamplesModel::column_name(int column) const
         return "#";
     case Column::Timestamp:
         return "Timestamp";
+    case Column::ProcessID:
+        return "PID";
     case Column::ThreadID:
         return "TID";
     case Column::ExecutableName:
@@ -50,7 +52,7 @@ String SamplesModel::column_name(int column) const
 
 GUI::Variant SamplesModel::data(const GUI::ModelIndex& index, GUI::ModelRole role) const
 {
-    u32 event_index = m_profile.first_filtered_event_index() + index.row();
+    u32 event_index = m_profile.filtered_event_indices()[index.row()];
     auto& event = m_profile.events().at(event_index);
 
     if (role == GUI::ModelRole::Custom) {
@@ -61,12 +63,14 @@ GUI::Variant SamplesModel::data(const GUI::ModelIndex& index, GUI::ModelRole rol
         if (index.column() == Column::SampleIndex)
             return event_index;
 
+        if (index.column() == Column::ProcessID)
+            return event.pid;
+
         if (index.column() == Column::ThreadID)
             return event.tid;
 
         if (index.column() == Column::ExecutableName) {
-            // FIXME: More abuse of the PID/TID relationship:
-            if (auto* process = m_profile.find_process(event.tid))
+            if (auto* process = m_profile.find_process(event.pid, event.timestamp))
                 return process->executable;
             return "";
         }