We have a new, improved string type coming up in AK (OOM aware, no null
state), and while it's going to use UTF-8, the name UTF8String is a
mouthful - so let's free up the String name by renaming the existing
class.
Making the old one have an annoying name will hopefully also help with
quick adoption :^)
This changes browsing through disassembled functions in Profiler from a
painfully sluggish experience into quite a swift one. It's especially
true for profiling the kernel, as it has more than 10 megabytes of DWARF
data to churn through.
Previously, we assumed that the `.text` segment was loaded at vaddr 0 in
shared object, which is not the case with `-z separate-code` enabled.
Because we didn't do the right calculations to translate an address from
a performance event into its value within the ELF file, Profiler would
try to disassemble out-of-bounds memory locations, leading to a crash.
This commit also changes `LibraryMetadata` to apply to a loaded library
as a whole, not just to one of its segments (like .text or .data). This
lets us simplify the interface, as we no longer have to worry about
`text_base`.
Fixes#10628
Previously Profiler was using timestamps to distinguish processes.
However it is possible that separate processes with the same PID exist
at the exact same timestamp (e.g. for execve). This changes Profiler
to use unique serial numbers for each event instead.
This patch adds an additional level of hierarchy to the call tree:
Every process gets its own top-level node. :^)
Before this, selecting multiple processes would get quite confusing
as all the call stacks from different processes were combined together
into one big tree.
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.
