Re: [PATCH v2 2/2] perf test: Add support for setting objdump binary via perf config

From: Arnaldo Carvalho de Melo
Date: Wed Nov 08 2023 - 16:10:47 EST


Em Wed, Nov 08, 2023 at 05:53:34PM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Mon, Nov 06, 2023 at 03:10:49PM +0000, James Clark escreveu:
> > Add a perf config variable that does the same thing as "perf test
> > --objdump <x>".
> >
> > Also update the man page.
>
> That is ok, if one wants to change objdump just for testing, as a
> followup improvement it may be interesting to allow that for the other
> tools that have --objdump as well as to add this as a global option,
> that affects all tools, no?
>
> Anyway, applied both patches.

And added this to the last one:

Committer testing:

# perf config test.objdump
# perf test "object code reading"
26: Object code reading : Ok
# perf config test.objdump=blah
# perf config test.objdump
test.objdump=blah
# perf test "object code reading"
26: Object code reading : FAILED!
# perf test -v "object code reading"
26: Object code reading :
--- start ---
test child forked, pid 600599
Looking at the vmlinux_path (8 entries long)
Using /proc/kcore for kernel data
Using /proc/kallsyms for symbols
Parsing event 'cycles'
Using CPUID AuthenticAMD-25-21-0
mmap size 528384B
Reading object code for memory address: 0x4d9a02
File is: /home/acme/bin/perf
On file address is: 0xd9a02
Objdump command is: blah -z -d --start-address=0x4d9a02 --stop-address=0x4d9a82 /home/acme/bin/perf
objdump read too few bytes: 128
Bytes read differ from those read by objdump
buf1 (dso):
0x48 0x85 0xff 0x74 0x29 0xe8 0x94 0xdf 0x07 0x00 0x8b 0x73 0x1c 0x48 0x8b 0x43
0x08 0xeb 0xa5 0x0f 0x1f 0x00 0x48 0x8b 0x45 0xe8 0x64 0x48 0x2b 0x04 0x25 0x28
0x00 0x00 0x00 0x75 0x0f 0x48 0x8b 0x5d 0xf8 0xc9 0xc3 0x0f 0x1f 0x00 0x48 0x8b
0x43 0x08 0xeb 0x84 0xe8 0xc5 0x3e 0xf3 0xff 0x0f 0x1f 0x44 0x00 0x00 0x55 0x48
0x89 0xe5 0x41 0x56 0x41 0x55 0x49 0x89 0xd5 0x41 0x54 0x49 0x89 0xfc 0x53 0x48
0x89 0xf3 0x48 0x83 0xec 0x30 0x48 0x8b 0x7e 0x20 0x64 0x48 0x8b 0x04 0x25 0x28
0x00 0x00 0x00 0x48 0x89 0x45 0xd8 0x31 0xc0 0x48 0x89 0x75 0xb0 0x48 0xc7 0x45
0xb8 0x00 0x00 0x00 0x00 0x48 0xc7 0x45 0xc0 0x00 0x00 0x00 0x00 0xe8 0xad 0xfa

buf2 (objdump):
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00

test child finished with -1
---- end ----
Object code reading: FAILED!
# perf config test.objdump=/usr/bin/objdump
# perf config test.objdump
test.objdump=/usr/bin/objdump
# perf test "object code reading"
26: Object code reading : Ok
#

Signed-off-by: James Clark <james.clark@xxxxxxx>
Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>