Disassembly reports generated by pprof -disasm will now include line number
information as generated by objdump. This will make the generated assembly more
readable.
As part of this I've introduced a new assemblyInstruction struct. Previously
the code was reusing the graph.Node to represent assembly instructions but it
seems better to have a dedicated type for this.
Do not hide allocation frames under call32/call64.
See https://github.com/google/pprof/issues/54. Frames under
call32/call64 may be user code frames so should be shown to avoid
confusing re-attribution of allocations to the calling system frames.
A previous commit tried to eliminate a panic when reading an empty
profile by stopping support for profiles with no samples. That is
unnecessary and it can obstruct some testing.
The panic was caused by the legacy parser returning a nil profile and
no error when processing an empty profile. Detect that situation and
generate a proper profile instead.
Tested by running 'pprof /dev/null'
Add testcase for profile parsing errors
Do not remove a residual edge between A and B if there isn't another path
going between A and B. We previously would remove it if A and B had a common
ancestor, but that caused some value duplication as A could become a leaf
but its value would still be accounted for in B.
Only create $HOME/pprof if a profile is stored remotely
and must be stored. Also, create non-profile temps on
os.TempDir() instead of $HOME/pprof or /tmp.
Ensure symbolz is called after local symbolization
Even after local symbolization completes successfully we should
call remote symbolization in case there are some mapping that couldn't
be symbolized otherwise.
Add some tests to ensure both local and symbolz symbolization are called.
Reset mapping file to empty string if it was patched to be the source URL.
When the source is remote and a mapping doesn't have either build ID or
file field set, the file field is set to the source URL so that the
proper source from the source mapping is used during symbolz processing.
Before this change, the file field would continue to point to the URL
producing the URL in pprof output which confuses users.
With the change it resets the file field back to the empty string. It
also now skips the URL-like paths during local symbolization as
reading at that path is not going to succeed.
We discussed switching to generating more unique IDs. On the second
thought, I propose leaving these to be URLs as that seems unique enough
and in case this field leaks into the tool or log output seeing the URL
seems still friendlier than some arbitrarily prefixed string.
The kernel mapping record has the offset of 0xc000000000000000 on
PowerPC64 along with the same value for the mapping start. Both values
come from arch/powerpc/Kconfig. This case is not handled by any of the
conditions in the current getBase() code, so update the existing code
handling the kernel case to handle the PowerPC64 case.
When -mean is selected, currently pprof divides the sample value
by value[0], which is expected to be the number of samples. This
is intended to produce mean value per sample. These means cannot
be added. Instead, we should add the value and the number of samples
independently and perform the division at the end.
To do this we will create a separate function to get the number of samples,
and accumulate it independently from the sample value (weigth) and apply
the division after the accumulation is completed.
Raul Silvera