Re: arm64 kprobes/systemtap support progress

[William Cohen <wcohen at redhat dot com>]

After some some minor fixes (pr17622) the arm64 systemtap test results
are looking much better now:

		=== systemtap Summary ===

# of expected passes		3475
# of unexpected failures	112
# of unexpected successes	1
# of expected failures		312
# of unknown successes		2
# of known failures		59
# of untested testcases		408
# of unsupported tests		17
runtest completed at Wed Nov 19 12:59:55 2014

The summary has been upleaded to dejazilla: 

https://web.elastic.org/~dejazilla/viewsummary.php?summary=%3D%27%3C546CDB29.5020709%40redhat.com%3E%27

I did a quick look over of the current results and categorized most of
them below.

The following tests are failing because systemtap not recognizing the name in the SDT_V3 output:

FAIL: singleparam (3)
FAIL: return (0)
FAIL: multiparams (0)
FAIL: stacktrace (0)
FAIL: ./systemtap.base/sdt_varname.stp sdt_varname libsdt_varname.so -c ./sdt_varname


Unable to find target variable:

FAIL: at_var_tracepoint compilation
FAIL: at_var_void_stmt (0, 2)
FAIL: global_var_kernel compilation
FAIL: ./systemtap.examples/network/netdev build
FAIL: ./systemtap.examples/network/tcp_trace build
FAIL: buildok/networking-detailed.stp
FAIL: buildok/nfs-detailed.stp
FAIL: buildok/nfsd-detailed.stp
FAIL: buildok/nfsd-embedded.stp
FAIL: buildok/seventeen.stp
FAIL: buildok/tty-detailed.stp
FAIL: buildok/xtime.stp
FAIL: semok/seventeen.stp
FAIL: semok/thirtynine.stp
FAIL: semok/thirtysix.stp

Unable to find a probe point:

FAIL: debugpath-good (eof)
FAIL: warnings (0)
FAIL: ./systemtap.examples/process/procmod_watcher build
FAIL: buildok/nfs-all-probes.stp
FAIL: buildok/nfs_proc-detailed.stp
FAIL: buildok/vfs-all-probes.stp
FAIL: buildok/vfs-detailed.stp
FAIL: semok/doubleglob.stp

Uprobes support not available:

FAIL: bad-code
FAIL: callee (simple - probing .callee(foo))
FAIL: callee (multicalls - probing main .callees)
FAIL: callee (inlined - probing main .callees)
FAIL: callee (extern - probing main .callees)
FAIL: callee (reloc - probing shlib foo .callees)
FAIL: pr16719 (user - can't start stap)
FAIL: sdt_misc wildcard (0) V1_uprobe
FAIL: sdt_misc wildcard (0) V2_uprobe
FAIL: sdt_misc wildcard (0) V3_uprobe
FAIL: stmt_inlines (probing error, expected 4, got 0)
FAIL: stmt_rel (bio_init sanity check)
FAIL: 64_BIT_UTRACE_SYSCALL_ARGS shutdown (eof)
FAIL: ./systemtap.examples/general/py2example build
FAIL: ./systemtap.examples/memory/last_100_frees build

backtracing not working properly:

FAIL: caller shutdown (eof)
FAIL: early test shutdown (m2 eof)
FAIL: backtrace of yyy_func2 (0)
FAIL: print_syms of yyy_func2 (2)
FAIL: backtrace of yyy_func3 (0)
FAIL: print_syms of yyy_func3 (0)
FAIL: backtrace of yyy_func4 (0)
FAIL: print_syms of yyy_func4 (0)
FAIL: print_syms didn't find systemtap_test_module1 (0)
FAIL: print_syms didn't find [kernel] (0)
FAIL: backtrace.stp didn't call exit (0)

time issue:

FAIL: gtod (100ms interval) (19)

plt support not impletement:

FAIL: listing_mode (untested probe type: process(number).plt)
FAIL: listing_mode (untested probe type: process(number).plt.return)
FAIL: listing_mode (untested probe type: process(number).plt(string))
FAIL: listing_mode (untested probe type: process(number).plt(string).return)

problem with register access (sp (reg 31) not part of pt_reg array):

FAIL: rlimit unlimited
FAIL: rlimit AS increase (as root)
FAIL: rlimit AS realistic
FAIL: rlimit CPU increase (as root)
FAIL: rlimit CPU realistic
FAIL: rlimit NPROC increase (as root)
FAIL: rlimit NPROC realistic
FAIL: rlimit STACK increase (as root)
FAIL: rlimit STACK realistic
FAIL: rlimit FSIZE increase (as root)
FAIL: rlimit FSIZE realistic

Funky kernel name (has '+'):
FAIL: Valid Server Client Arguments: --client-options -r UNAME
FAIL: Valid Server Client Arguments: --client-options -a i386 -D X=Y -I foo -m test -r UNAME


depricated syscalls removed on arm64:

28 nd_syscall and syscall tests failed most of these appear to be
because of the depreciated syscalls not being implemented on arm64

-Will