This is an (incomplete) list of some of the stuff we want to look at doing.
If you're interested in hacking on any of these, please contact the list first
for some pointers and/or read HACKING and doc/CodingStyle.
1.0 release
-----------
(this is a minimal selection of stuff I think we need)
o amd64 32 bit build needs a sys32_lookup_dcookie() translator in the
kernel
o decide on -m tgid semantics for anon regions
o if ev67 is not fixed, back it out
o lapic : module should says "didn't find apic" if needed, FAQ and doc should
speak a bit about lapic kernel option on x86 and recent kernel
o see the big comment in db_insert.c, it's possible to allow unlimited
amount of samples with a very minor change in libdb.
o if oprofilee doesn't recognize the processor selected by the kernel
opcontrol could setup the module in timer mode (remove/reload prolly), and
warn the user it must upgrade oprofile to get all the feature from its
hardware.
Later
-----
o remove 2.95/2.2 support so we can use boost multi index container in
symbol/sample container
o consider if we can improve anon mapping growing support
<movement> [moz@lambent pp]$ ./opreport -lf lib-image:/lib/tls/libc-2.3.2.so /bin/bash | grep vfprintf
<movement> 14 0.1301 6 0.0102 /lib/tls/libc-2.3.2.so vfprintf
<movement> [moz@lambent pp]$ ./opreport -lf lib-image:/lib/tls/libc-2.3.2.so /usr/bin/vim | grep vfprintf
<movement> 176 2.0927 349 1.2552 /lib/tls/libc-2.3.2.so vfprintf
<movement> [moz@lambent pp]$ ./opreport -lf lib-image:/lib/tls/libc-2.3.2.so { image:/bin/bash } { image:/usr/bin/vim } | grep vfprintf
<movement> 176 10.9657 +++ 349 7.8888 +++ vfprintf
<movement> 14 --- --- 6 --- --- vfprintf
<movement> it seems them as two separate symbols
<movement> but can we remove the app_name from rough_less and still be able to walk the two lists?
<movement> even if we could, it would still go wrong when we're profiling multiple apps
o Java stuff??
o with opreport -c I can get "warning: /no-vmlinux could not be found.".
Should be smarter ?
o opreport -c gives weird output for an image with no symbols:
samples % symbol name
15965 100.000 (no symbols)
253 100.000 (no symbols)
15965 98.4400 (no symbols)
253 1.5600 (no symbols) [self]
o consider tagging opreport -c entries with a number like gprof
o --details for opreport -c, or diff??
o should [self] entries be ommitted if 0 ??
o stress test opreport -c: compile a Big Application w/o frame pointer and look
how driver and opreport -c react.
o oparchive could fix up {kern} paths with -p (what about diff between
archive and current though?)
o can say more in opcontrol --status
o consider a sort option for diff %
o opannotate is silent about symbols missing debug info
o opcontrol --reset should avoid to reload the module if it's unloaded
o oprofiled.log now contains various statistics about lost sample etc. from
the driver. Post profile tools must parse that and warn eventually, warning
must include a proposed work around. User need this: if nothing seems wrong
people are unlikely to get a look in oprofiled.log (I ran oprofile on 2.6.1
2 weeks before noticing at 30000 I lost a lot of samples, the profile seemed
ok du to the randomization of lost samples). As developper we need that too,
actually we have no clear idea of the behavior on different arch, NUMA etc.
Not perfect because if the profiler is running the oprofiled.log will show
those warning only after the first alarm signal, I think we must dump the
statistics information after each opcontrol --dump to avoid that.
o odb_insert() can fail on ftruncate or mremap() in db_manage.c but we don't
try to recover gracefully.
o output column shortname headers for opreport -l
o is relative_to_absolute_path guaranteeing a trailing '/' documented ?
o move oprofiled.log to OP_SAMPLE_DIR/current ?
o pp tools must handle samples count overflow (marked as (unsigned)-1)
o the way we show kernel modules in 2.5 is not very obvious - "/oprofile"
o oparchive will be more usefull with a --root= options to allow profiling
on a small box, nfs mount / to another box and transfer sample file and
binary on a bigger box for analysis. There is also a problem in oparchive
you can use session: to get the right path to samples files but oprofiled.log
and abi files path are hardcoded to /var/lib/oprofile.
o callgraph patch: better way to skip ignored backtrace ?
o lib-image: and image: behavior depend on --separate=, if --separate=library
opreport "lib-image:*libc*" --merge=lib works but not
opreport "image:*libc*" --merge=lib whilst the behavior is reversed if
--separate==none. Must we take care ?
o dependencies between profile_container.h symbol_container.h and
sample_container.h become more and more ugly, I needed to include them
in a specific order in some source (still true??)
o add event aliases for common things like icache misses, we must start to
think about metrics including simple like event alias mapped to two or more
events and intepreted specially by user space tools like using the ratio
of samples; more tricky will be to select an event used as call count (no
cg on it) and used to emulate the call count field in gprof. I think this is
a after 1.0 thing but event aliases must be specified in a way allowing such
extension
o do we need an opreport like opreport -c (showing caller/callee at binary
boundary not symbols) ?
o we should notice an opcontrol config change (--separate etc.) and
auto-restart the daemon if necessary (Run)
o we can add lots more unit tests yet
o Itanium event constraints are not implemented
o GUI still has a physical-counter interface, should have a general one
like opcontrol --event
o I think we should have the ability to have *fixed* width headers, e.g. :
vma samples cum. samples % cum. % symbol name image name app name
0804c350 64582 64582 35.0757 35.0757 odb_insert /usr/loc...in/oprofiled /usr/local/oprofile-pp/bin/oprofiled
Note the ellipsis
o should we make the sighup handler re-read counter config and re-start profiling too ?
o improve --smart-demangle
o allow user to add it's own pattern in user.pat, document it.
o hard code ${typename} regular definition to remove all current limitations (difficult, perhaps after 1.0 ?).
o oprof_start dialog size is too small initially
o i18n. We need a good formatter, and also remember format_percent()
o opannotate --source --output-dir=~moz/op/ /usr/bin/oprofiled
will fail because the ~ is not expanded (no space around it) (popt bug I say)
o cpu names instead of numbers in 2.4 module/ ?
o remove 1 and 2 magic numbers for oprof_ready
o adapt Anton's patch for handling non-symbolled libraries ? (nowaday C++
anon namespace symbol are static, 3.4 iirc, so with recent distro we are
more likely to get problems with a "fallback to dynamic symbols" approch)
o use standard C integer type <stdint.h> int32_t int16_t etc.
o event multiplexing for real
o randomizing of reset value
o XML output
o profile the NMI handler code
o opannotate : I added this to the doc about difference between nr samples
credited to a source function and total number of samples for this function:
"The missing samples are not lost, they will be credited to another source
location where the inlined function is defined. The inlined function will
be credited from multiple call site and merged in one place in the
annotated source file so there is no way to see from what call site are
coming the samples for an inlined function."
I think we can work around this: output multiple instances of inlined
function like :
inline foo() { foo: total 1500 30.00 ...
... annotated source from all call site
inline foo() { foo (call site bar()): total 500 10.00
.. annotated source from call site bar() etc.
what about template..., can we do/must we do something like that
template <class T> eat_cpu() and do a similar things, merging and annotating
all instantation then annotating for each distinct instantation, this will
break our "keep the source line number in annotated source file identical to
the original source"
Documentation
-------------
o the docs should mention the default event for each arch somewhere
o more discussion of problematic code needs to go in the "interpreting" section.
o document gcc 2.95 and linenr info problems especially for inline functions
o finish the internals manual
General checks to make
----------------------
o rgrep FIXME
o valgrind (--show-reachable=yes --leak-check=yes)
o audit to track unnecessary include <>
o gcc 3.0/3.x compile
o Qt2/3 check, no Qt check
o verify builds (modversions, kernel versions, athlon etc.). I have the
necessary stuff to check kernel versions/configurations on PIII core (Phil)
o use nm and a little script to track unused function
o test it to hell and back
o compile all C++ programs with STL_port and test them (gcc 3.4 contain a
debug mode too but std::string iterator are not checked)
o There is probably place of post profile tools where looking at errno will give better error messages.
