On Wed, Mar 21, 2018 at 10:11:10AM +0800, Jin, Yao wrote: > Hi Jiri, > > I'm still thinking it's worth displaying the warning when perf missing some > libraries. > > Somebody just told me that perf didn't work well. While after some > investigations, I found it's just missing some libraries when building the > perf. > > But I have spent some time on getting the root cause. If with this patch, it > should be very easily to know that.
true.. Arnaldo, any feedback on this one? > > I just think it'd better provide some hints to user. For example, > > "symbol is disabled and you need to install libelf/xxx", say something > > like that. > > > > But it looks the column can't contain too much information (i.e. no more > > space to contain the entire hints). > > > > Any idea? Or just add this warning in verbose mode? > > > > > also your change does not affect tui mode > > > > > > annotation for some reason does not start at all.. could be > > > little more verbose ;-) > > > > > > jirka > > > > > > > Yes, it doesn't affect tui mode. > > > > Or we just add this warning in verbose mode? > > > > e.g. perf report -v? how about displaying libraries separately with -vv output, that would mimic the build message, like: $ ./perf -vv perf version 4.16.rc6.g18fd48 dwarf: [ on ] dwarf_getlocations: [ on ] glibc: [ on ] gtk2: [ on ] libaudit: [ on ] libbfd: [ on ] libelf: [ on ] libnuma: [ on ] numa_num_possible_cpus: [ on ] libperl: [ on ] libpython: [ on ] libslang: [ on ] libcrypto: [ on ] libunwind: [ on ] libdw-dwarf-unwind: [ on ] zlib: [ on ] lzma: [ on ] get_cpuid: [ on ] bpf: [ on ] and perf -vvv could display the 'make VF=1' info jirka