This adds a new view mode to profiler which displays source lines and
samples that occured at those lines. This view can be opened via the
menu or by pressing CTRL-S.
It does this by mapping file names from DWARF to "/usr/src/serenity/..."
i.e. source code should be copied to /usr/src/serenity/Userland and
/usr/src/serenity/Kernel to be visible in this mode.
Currently *all* files contributing to the selected function are loaded
completely which could be a lot of data when dealing with lots of
inlined code.
This removes all the hard-coded kernel base addresses from userspace
tools.
One downside for this is that e.g. Profiler no longer uses a different
color for kernel symbols when run as a non-root user.
The architecture here is a little bit convoluted. I ended up making a
new container widget (TimelineContainer) that works similarly to
GUI::ScrollableContainerWidget but has two subwidgets (a fixed header
that only scrolls vertically, and the timeline view that scrolls on
both axes.)
It would be nice to generalize this mechanism eventually and move it
back into LibGUI, but for now let's go with a special widget for
Profiler so we can continue iterating on the GUI. :^)
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.
You can now view the individual samples in a profile one by one with
the new "Samples" view. The "old" main view moves into a "Call Tree"
tab (but it remains the default view.)
When you select a sample in the samples view, we show you the full
symbolicated backtrace in a separate view on the right hand side. :^)
