On Mon, Mar 09, 2020 at 06:24:22PM +0000, Song Liu wrote: > > > > On Mar 9, 2020, at 11:04 AM, Quentin Monnet <quentin@xxxxxxxxxxxxx> wrote: > > > > 2020-03-04 21:39 UTC+0000 ~ Song Liu <songliubraving@xxxxxx> > >> > >> > >>> On Mar 4, 2020, at 1:29 PM, Jiri Olsa <jolsa@xxxxxxxxxx> wrote: > >>> > >>> On Wed, Mar 04, 2020 at 09:16:29PM +0000, Song Liu wrote: > >>>> > >>>> > >>>>> On Mar 4, 2020, at 12:41 PM, Jiri Olsa <jolsa@xxxxxxxxxx> wrote: > >>>>> > >>>>> On Wed, Mar 04, 2020 at 08:08:07PM +0100, Jiri Olsa wrote: > >>>>>> On Wed, Mar 04, 2020 at 10:07:06AM -0800, Song Liu wrote: > >>>>>>> This set introduces bpftool prog profile command, which uses hardware > >>>>>>> counters to profile BPF programs. > >>>>>>> > >>>>>>> This command attaches fentry/fexit programs to a target program. These two > >>>>>>> programs read hardware counters before and after the target program and > >>>>>>> calculate the difference. > >>>>>>> > >>>>>>> Changes v3 => v4: > >>>>>>> 1. Simplify err handling in profile_open_perf_events() (Quentin); > >>>>>>> 2. Remove redundant p_err() (Quentin); > >>>>>>> 3. Replace tab with space in bash-completion; (Quentin); > >>>>>>> 4. Fix typo _bpftool_get_map_names => _bpftool_get_prog_names (Quentin). > >>>>>> > >>>>>> hum, I'm getting: > >>>>>> > >>>>>> [jolsa@dell-r440-01 bpftool]$ pwd > >>>>>> /home/jolsa/linux-perf/tools/bpf/bpftool > >>>>>> [jolsa@dell-r440-01 bpftool]$ make > >>>>>> ... > >>>>>> make[1]: Leaving directory '/home/jolsa/linux-perf/tools/lib/bpf' > >>>>>> LINK _bpftool > >>>>>> make: *** No rule to make target 'skeleton/profiler.bpf.c', needed by 'skeleton/profiler.bpf.o'. Stop. > >>>>> > >>>>> ok, I had to apply your patches by hand, because 'git am' refused to > >>>>> due to fuzz.. so some of you new files did not make it to my tree ;-) > >>>>> > >>>>> anyway I hit another error now: > >>>>> > >>>>> CC prog.o > >>>>> In file included from prog.c:1553: > >>>>> profiler.skel.h: In function ‘profiler_bpf__create_skeleton’: > >>>>> profiler.skel.h:136:35: error: ‘struct profiler_bpf’ has no member named ‘rodata’ > >>>>> 136 | s->maps[4].mmaped = (void **)&obj->rodata; > >>>>> | ^~ > >>>>> prog.c: In function ‘profile_read_values’: > >>>>> prog.c:1650:29: error: ‘struct profiler_bpf’ has no member named ‘rodata’ > >>>>> 1650 | __u32 m, cpu, num_cpu = obj->rodata->num_cpu; > >>>>> > >>>>> I'll try to figure it out.. might be error on my end > >>>>> > >>>>> do you have git repo with these changes? > >>>> > >>>> I pushed it to > >>>> > >>>> https://git.kernel.org/pub/scm/linux/kernel/git/song/linux.git/tree/?h=bpf-per-prog-stats > >>> > >>> still the same: > >>> > >>> [jolsa@dell-r440-01 bpftool]$ git show --oneline HEAD | head -1 > >>> 7bbda5cca00a bpftool: fix typo in bash-completion > >>> [jolsa@dell-r440-01 bpftool]$ make > >>> make[1]: Entering directory '/home/jolsa/linux-perf/tools/lib/bpf' > >>> make[1]: Leaving directory '/home/jolsa/linux-perf/tools/lib/bpf' > >>> CC prog.o > >>> In file included from prog.c:1553: > >>> profiler.skel.h: In function ‘profiler_bpf__create_skeleton’: > >>> profiler.skel.h:136:35: error: ‘struct profiler_bpf’ has no member named ‘rodata’ > >>> 136 | s->maps[4].mmaped = (void **)&obj->rodata; > >>> | ^~ > >>> prog.c: In function ‘profile_read_values’: > >>> prog.c:1650:29: error: ‘struct profiler_bpf’ has no member named ‘rodata’ > >>> 1650 | __u32 m, cpu, num_cpu = obj->rodata->num_cpu; > >>> | ^~ > >>> prog.c: In function ‘profile_open_perf_events’: > >>> prog.c:1810:19: error: ‘struct profiler_bpf’ has no member named ‘rodata’ > >>> 1810 | sizeof(int), obj->rodata->num_cpu * obj->rodata->num_metric); > >>> | ^~ > >>> prog.c:1810:42: error: ‘struct profiler_bpf’ has no member named ‘rodata’ > >>> 1810 | sizeof(int), obj->rodata->num_cpu * obj->rodata->num_metric); > >>> | ^~ > >>> prog.c:1825:26: error: ‘struct profiler_bpf’ has no member named ‘rodata’ > >>> 1825 | for (cpu = 0; cpu < obj->rodata->num_cpu; cpu++) { > >>> | ^~ > >>> prog.c: In function ‘do_profile’: > >>> prog.c:1904:13: error: ‘struct profiler_bpf’ has no member named ‘rodata’ > >>> 1904 | profile_obj->rodata->num_cpu = num_cpu; > >>> | ^~ > >>> prog.c:1905:13: error: ‘struct profiler_bpf’ has no member named ‘rodata’ > >>> 1905 | profile_obj->rodata->num_metric = num_metric; > >>> | ^~ > >>> make: *** [Makefile:129: prog.o] Error 1 > >> > >> I guess you need a newer version of clang that supports global data in BPF programs. > >> > >> Thanks, > >> Song > >> > > > > Thinking about this requirement again... Do you think it would be worth > > adding (as a follow-up) a feature check on the availability of clang > > with global data support to bpftool's Makefile? So that we could compile > > out program profiling if clang is not present or does not support it. > > Just like libbfd support is optional already. > > > > I'm asking mostly because a number of distributions now package bpftool, > > and e.g. Ubuntu builds it from kernel source when creating its > > linux-images and linux-tools-* packages. And I am pretty sure the build > > environment does not have latest clang/LLVM, but it would be great to > > remain able to build bpftool. > > Yeah, I think it is a good idea. Some more Makefile fun. ;) I think it's good idea, also bpftool is already using feature detection from tools/build/features.. you can check commits like: fb982666e380 tools/bpftool: fix bpftool build with bintutils >= 2.9 for adding new feature detection jirka
