Re: Recent aarch64 kprobes and uprobes patch systemtap testing

[William Cohen <wcohen@redhat.com>]

On 12/16/2015 12:22 AM, Pratyush Anand wrote:
> On 11/12/2015:12:02:21 PM, William Cohen wrote:
>>
>> The "FAIL: pthread_stacks -Gsize (0 0)" looks like it could be an issue with uprobes affecting the running of the program.  Pratyush are you able to run this systemtap test locally?
> 
> Even when I run this test locally it does not work, but it fails very early in
> my case. May be because of different libpthread.so
> 
> [root@amd-seattle-01 testsuite]# /root/bin/systemtap/bin/stap -gp4 ./systemtap.examples/process/threadstacks.stp -Gsize=65536 -d /root/systemtap/testsuite/pthread_stacks.x
> semantic error: while resolving probe point: identifier 'process' at ./systemtap.examples/process/threadstacks.stp:17:7
>         source: probe process("/lib*/libpthread.so.*").function("allocate_stack") {
>                       ^
> 
> semantic error: no match

You might need to install glibc-debuginfo.  Below is some information from the machine I have setup showing that the probe point is available and what glibc stuff is installed on the machine:

[root@apm-mustang-ev3-01 systemtap]# ../install/bin/stap -L 'process("/lib*/libpthread.so.*").function("allocate_stack")'
process("/usr/lib64/libpthread-2.17.so").function("allocate_stack@/usr/src/debug/glibc-2.17-c758a686/nptl/allocatestack.c:344") $stack:void** $pdp:struct pthread** $attr:struct pthread_attr const*
[root@apm-mustang-ev3-01 systemtap]# rpm -qf /usr/lib64/libpthread-2.17.so 
glibc-2.17-105.el7.aarch64
[root@apm-mustang-ev3-01 systemtap]# rpm -qa|grep glibc
glibc-common-2.17-105.el7.aarch64
glibc-devel-2.17-105.el7.aarch64
glibc-debuginfo-2.17-105.el7.aarch64
glibc-headers-2.17-105.el7.aarch64
glibc-2.17-105.el7.aarch64

-Will

> 
> Pass 2: analysis failed.  [man error::pass2]
> [root@amd-seattle-01 testsuite]# ls /lib*/libpthread.so.*
> /lib64/libpthread.so.0
> [root@amd-seattle-01 testsuite]# ll /lib64/libpthread.so.0
> lrwxrwxrwx. 1 root root 18 Dec 13 23:42 /lib64/libpthread.so.0 -> libpthread-2.17.so
> [root@amd-seattle-01 testsuite]# objdump -d /lib64/libpthread.so.0 | grep allocate_stack
> 0000000000006a50 <__deallocate_stack>:
>     6a7c:       54000061        b.ne    6a88 <__deallocate_stack+0x38>
>     6a84:       35ffff83        cbnz    w3, 6a74 <__deallocate_stack+0x24>
>     6a88:       540005e1        b.ne    6b44 <__deallocate_stack+0xf4>
>     6a90:       350005e0        cbnz    w0, 6b4c <__deallocate_stack+0xfc>
>     6ac4:       350005e2        cbnz    w2, 6b80 <__deallocate_stack+0x130>
>     6b14:       54000328        b.hi    6b78 <__deallocate_stack+0x128>
>     6b2c:       35ffffc2        cbnz    w2, 6b24 <__deallocate_stack+0xd4>
>     6b34:       5400014c        b.gt    6b5c <__deallocate_stack+0x10c>
>     6b48:       17ffffd1        b       6a8c <__deallocate_stack+0x3c>
>     6b58:       17ffffcf        b       6a94 <__deallocate_stack+0x44>
>     6b74:       17fffff1        b       6b38 <__deallocate_stack+0xe8>
>     6b7c:       17ffffe7        b       6b18 <__deallocate_stack+0xc8>
>     6b8c:       17ffffe3        b       6b18 <__deallocate_stack+0xc8>
>     6c3c:       97ffff85        bl      6a50 <__deallocate_stack>
>     7ce4:       97fffb5b        bl      6a50 <__deallocate_stack>
>     7f04:       97fffad3        bl      6a50 <__deallocate_stack>
>     894c:       97fff841        bl      6a50 <__deallocate_stack>
> [root@amd-seattle-01 testsuite]#
> 
> ~Pratyush
>