summaryrefslogtreecommitdiffstats
path: root/tools/perf/util/bpf_counter.c
Commit message (Collapse)AuthorAgeFilesLines
* tools: Replace btf__get_from_id() with btf__load_from_kernel_by_id()Quentin Monnet2021-07-291-2/+7
| | | | | | | | | | | | | Replace the calls to function btf__get_from_id(), which we plan to deprecate before the library reaches v1.0, with calls to btf__load_from_kernel_by_id() in tools/ (bpftool, perf, selftests). Update the surrounding code accordingly (instead of passing a pointer to the btf struct, get it as a return value from the function). Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20210729162028.29512-6-quentin@isovalent.com
* tools: Free BTF objects at various locationsQuentin Monnet2021-07-291-1/+2
| | | | | | | | | | | | | | | | | | Make sure to call btf__free() (and not simply free(), which does not free all pointers stored in the struct) on pointers to struct btf objects retrieved at various locations. These were found while updating the calls to btf__get_from_id(). Fixes: 999d82cbc044 ("tools/bpf: enhance test_btf file testing to test func info") Fixes: 254471e57a86 ("tools/bpf: bpftool: add support for func types") Fixes: 7b612e291a5a ("perf tools: Synthesize PERF_RECORD_* for loaded BPF programs") Fixes: d56354dc4909 ("perf tools: Save bpf_prog_info and BTF of new BPF programs") Fixes: 47c09d6a9f67 ("bpftool: Introduce "prog profile" command") Fixes: fa853c4b839e ("perf stat: Enable counting events for BPF programs") Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210729162028.29512-5-quentin@isovalent.com
* libperf: Move 'leader' from tools/perf to perf_evsel::leaderJiri Olsa2021-07-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move evsel::leader to perf_evsel::leader, so we can move the group interface to libperf. Also add several evsel helpers to ease up the transition: struct evsel *evsel__leader(struct evsel *evsel); - get leader evsel bool evsel__has_leader(struct evsel *evsel, struct evsel *leader); - true if evsel has leader as leader bool evsel__is_leader(struct evsel *evsel); - true if evsel is itw own leader void evsel__set_leader(struct evsel *evsel, struct evsel *leader); - set leader for evsel Committer notes: Fix this when building with 'make BUILD_BPF_SKEL=1' tools/perf/util/bpf_counter.c - if (evsel->leader->core.nr_members > 1) { + if (evsel->core.leader->nr_members > 1) { Signed-off-by: Jiri Olsa <jolsa@kernel.org> Requested-by: Shunsuke Nakamura <nakamura.shun@fujitsu.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Petlan <mpetlan@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lore.kernel.org/lkml/20210706151704.73662-4-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf stat: Enable BPF counter with --for-each-cgroupNamhyung Kim2021-07-051-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | Recently bperf was added to use BPF to count perf events for various purposes. This is an extension for the approach and targetting to cgroup usages. Unlike the other bperf, it doesn't share the events with other processes but it'd reduce unnecessary events (and the overhead of multiplexing) for each monitored cgroup within the perf session. When --for-each-cgroup is used with --bpf-counters, it will open cgroup-switches event per cpu internally and attach the new BPF program to read given perf_events and to aggregate the results for cgroups. It's only called when task is switched to a task in a different cgroup. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20210701211227.1403788-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf bpf_counter: Move common functions to bpf_counter.hNamhyung Kim2021-07-011-52/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some helper functions will be used for cgroup counting too. Move them to a header file for sharing. Committer notes: Fix the build on older systems with: - struct bpf_map_info map_info = {0}; + struct bpf_map_info map_info = { .id = 0, }; This wasn't breaking the build in such systems as bpf_counter.c isn't built due to: tools/perf/util/Build: perf-$(CONFIG_PERF_BPF_SKEL) += bpf_counter.o The bpf_counter.h file on the other hand is included from places that are built everywhere. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20210625071826.608504-4-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf stat: Fix error return code in bperf__load()Yu Kuai2021-06-011-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix to return a negative error code from the error handling case instead of 0, as done elsewhere in this function. Committer notes: Added the missing {} for the now multiline 'if' block, fixing this error: CC /tmp/build/perf/util/bpf_counter.o util/bpf_counter.c: In function ‘bperf__load’: util/bpf_counter.c:523:9: error: this ‘if’ clause does not guard... [-Werror=misleading-indentation] 523 | if (evsel->bperf_leader_link_fd < 0 && | ^~ util/bpf_counter.c:526:17: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the ‘if’ 526 | goto out; | ^~~~ cc1: all warnings being treated as errors Fixes: 7fac83aaf2eecc9e ("perf stat: Introduce 'bperf' to share hardware PMCs with BPF") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <songliubraving@fb.com> Cc: Yu Kuai <yukuai3@huawei.com> Cc: Zhang Yi <yi.zhang@huawei.com> Link: http://lore.kernel.org/lkml/20210517081254.1561564-1-yukuai3@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf stat: Fix error check for bpf_program__attachNamhyung Kim2021-05-271-2/+2
| | | | | | | | | | | | | | | | | It seems the bpf_program__attach() returns a negative error code instead of a NULL pointer in case of error. Fixes: 7fac83aaf2ee ("perf stat: Introduce 'bperf' to share hardware PMCs with BPF") Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <songliubraving@fb.com> Link: http://lore.kernel.org/lkml/20210527220052.1657578-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf stat: Introduce bpf_counter_ops->disable()Song Liu2021-04-291-0/+26
| | | | | | | | | | | | | | | | | | | | Introduce bpf_counter_ops->disable(), which is used stop counting the event. Committer notes: Added a dummy bpf_counter__disable() to the python binding to avoid having 'perf test python' failing. bpf_counter isn't supported in the python binding. Signed-off-by: Song Liu <song@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Song Liu <songliubraving@fb.com> Cc: kernel-team@fb.com Link: https://lore.kernel.org/r/20210425214333.1090950-6-song@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf stat: Introduce ':b' modifierSong Liu2021-04-291-1/+1
| | | | | | | | | | | | | | | | Introduce 'b' modifier to event parser, which means use BPF program to manage this event. This is the same as --bpf-counters option, but only applies to this event. For example, perf stat -e cycles:b,cs # use bpf for cycles, but not cs perf stat -e cycles,cs --bpf-counters # use bpf for both cycles and cs Suggested-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/r/20210425214333.1090950-5-song@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf stat: Introduce config stat.bpf-counter-eventsSong Liu2021-04-291-1/+2
| | | | | | | | | | | | | | | | | | | | | | Currently, to use BPF to aggregate perf event counters, the user uses --bpf-counters option. Enable "use bpf by default" events with a config option, stat.bpf-counter-events. Events with name in the option will use BPF. This also enables mixed BPF event and regular event in the same sesssion. For example: perf config stat.bpf-counter-events=instructions perf stat -e instructions,cs The second command will use BPF for "instructions" but not "cs". Signed-off-by: Song Liu <song@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/r/20210425214333.1090950-4-song@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf bpf: check perf_attr_map is compatible with the perf binarySong Liu2021-04-291-0/+19
| | | | | | | | | | | | | | perf_attr_map could be shared among different version of perf binary. Add bperf_attr_map_compatible() to check whether the existing attr_map is compatible with current perf binary. Signed-off-by: Song Liu <song@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Song Liu <songliubraving@fb.com> Cc: kernel-team@fb.com Link: https://lore.kernel.org/r/20210425214333.1090950-3-song@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf util: Move bpf_perf definitions to a libperf headerSong Liu2021-04-291-24/+3
| | | | | | | | | | | | | | By following the same protocol, other tools can share hardware PMCs with perf. Move perf_event_attr_map_entry and BPF_PERF_DEFAULT_ATTR_MAP_PATH to bpf_perf.h for other tools to use. Signed-off-by: Song Liu <song@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Song Liu <songliubraving@fb.com> Cc: kernel-team@fb.com Link: https://lore.kernel.org/r/20210425214333.1090950-2-song@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf stat: Introduce 'bperf' to share hardware PMCs with BPFSong Liu2021-03-231-5/+514
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The perf tool uses performance monitoring counters (PMCs) to monitor system performance. The PMCs are limited hardware resources. For example, Intel CPUs have 3x fixed PMCs and 4x programmable PMCs per cpu. Modern data center systems use these PMCs in many different ways: system level monitoring, (maybe nested) container level monitoring, per process monitoring, profiling (in sample mode), etc. In some cases, there are more active perf_events than available hardware PMCs. To allow all perf_events to have a chance to run, it is necessary to do expensive time multiplexing of events. On the other hand, many monitoring tools count the common metrics (cycles, instructions). It is a waste to have multiple tools create multiple perf_events of "cycles" and occupy multiple PMCs. bperf tries to reduce such wastes by allowing multiple perf_events of "cycles" or "instructions" (at different scopes) to share PMUs. Instead of having each perf-stat session to read its own perf_events, bperf uses BPF programs to read the perf_events and aggregate readings to BPF maps. Then, the perf-stat session(s) reads the values from these BPF maps. Please refer to the comment before the definition of bperf_ops for the description of bperf architecture. bperf is off by default. To enable it, pass --bpf-counters option to perf-stat. bperf uses a BPF hashmap to share information about BPF programs and maps used by bperf. This map is pinned to bpffs. The default path is /sys/fs/bpf/perf_attr_map. The user could change the path with option --bpf-attr-map. Committer testing: # dmesg|grep "Performance Events" -A5 [ 0.225277] Performance Events: Fam17h+ core perfctr, AMD PMU driver. [ 0.225280] ... version: 0 [ 0.225280] ... bit width: 48 [ 0.225281] ... generic registers: 6 [ 0.225281] ... value mask: 0000ffffffffffff [ 0.225281] ... max period: 00007fffffffffff # # for a in $(seq 6) ; do perf stat -a -e cycles,instructions sleep 100000 & done [1] 2436231 [2] 2436232 [3] 2436233 [4] 2436234 [5] 2436235 [6] 2436236 # perf stat -a -e cycles,instructions sleep 0.1 Performance counter stats for 'system wide': 310,326,987 cycles (41.87%) 236,143,290 instructions # 0.76 insn per cycle (41.87%) 0.100800885 seconds time elapsed # We can see that the counters were enabled for this workload 41.87% of the time. Now with --bpf-counters: # for a in $(seq 32) ; do perf stat --bpf-counters -a -e cycles,instructions sleep 100000 & done [1] 2436514 [2] 2436515 [3] 2436516 [4] 2436517 [5] 2436518 [6] 2436519 [7] 2436520 [8] 2436521 [9] 2436522 [10] 2436523 [11] 2436524 [12] 2436525 [13] 2436526 [14] 2436527 [15] 2436528 [16] 2436529 [17] 2436530 [18] 2436531 [19] 2436532 [20] 2436533 [21] 2436534 [22] 2436535 [23] 2436536 [24] 2436537 [25] 2436538 [26] 2436539 [27] 2436540 [28] 2436541 [29] 2436542 [30] 2436543 [31] 2436544 [32] 2436545 # # ls -la /sys/fs/bpf/perf_attr_map -rw-------. 1 root root 0 Mar 23 14:53 /sys/fs/bpf/perf_attr_map # bpftool map | grep bperf | wc -l 64 # # bpftool map | tail 1265: percpu_array name accum_readings flags 0x0 key 4B value 24B max_entries 1 memlock 4096B 1266: hash name filter flags 0x0 key 4B value 4B max_entries 1 memlock 4096B 1267: array name bperf_fo.bss flags 0x400 key 4B value 8B max_entries 1 memlock 4096B btf_id 996 pids perf(2436545) 1268: percpu_array name accum_readings flags 0x0 key 4B value 24B max_entries 1 memlock 4096B 1269: hash name filter flags 0x0 key 4B value 4B max_entries 1 memlock 4096B 1270: array name bperf_fo.bss flags 0x400 key 4B value 8B max_entries 1 memlock 4096B btf_id 997 pids perf(2436541) 1285: array name pid_iter.rodata flags 0x480 key 4B value 4B max_entries 1 memlock 4096B btf_id 1017 frozen pids bpftool(2437504) 1286: array flags 0x0 key 4B value 32B max_entries 1 memlock 4096B # # bpftool map dump id 1268 | tail value (CPU 21): 8f f3 bc ca 00 00 00 00 80 fd 2a d1 4d 00 00 00 80 fd 2a d1 4d 00 00 00 value (CPU 22): 7e d5 64 4d 00 00 00 00 a4 8a 2e ee 4d 00 00 00 a4 8a 2e ee 4d 00 00 00 value (CPU 23): a7 78 3e 06 01 00 00 00 b2 34 94 f6 4d 00 00 00 b2 34 94 f6 4d 00 00 00 Found 1 element # bpftool map dump id 1268 | tail value (CPU 21): c6 8b d9 ca 00 00 00 00 20 c6 fc 83 4e 00 00 00 20 c6 fc 83 4e 00 00 00 value (CPU 22): 9c b4 d2 4d 00 00 00 00 3e 0c df 89 4e 00 00 00 3e 0c df 89 4e 00 00 00 value (CPU 23): 18 43 66 06 01 00 00 00 5b 69 ed 83 4e 00 00 00 5b 69 ed 83 4e 00 00 00 Found 1 element # bpftool map dump id 1268 | tail value (CPU 21): f2 6e db ca 00 00 00 00 92 67 4c ba 4e 00 00 00 92 67 4c ba 4e 00 00 00 value (CPU 22): dc 8e e1 4d 00 00 00 00 d9 32 7a c5 4e 00 00 00 d9 32 7a c5 4e 00 00 00 value (CPU 23): bd 2b 73 06 01 00 00 00 7c 73 87 bf 4e 00 00 00 7c 73 87 bf 4e 00 00 00 Found 1 element # # perf stat --bpf-counters -a -e cycles,instructions sleep 0.1 Performance counter stats for 'system wide': 119,410,122 cycles 152,105,479 instructions # 1.27 insn per cycle 0.101395093 seconds time elapsed # See? We had the counters enabled all the time. Signed-off-by: Song Liu <songliubraving@fb.com> Reviewed-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: kernel-team@fb.com Link: http://lore.kernel.org/lkml/20210316211837.910506-2-songliubraving@fb.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf stat: Enable counting events for BPF programsSong Liu2021-01-201-0/+314
Introduce 'perf stat -b' option, which counts events for BPF programs, like: [root@localhost ~]# ~/perf stat -e ref-cycles,cycles -b 254 -I 1000 1.487903822 115,200 ref-cycles 1.487903822 86,012 cycles 2.489147029 80,560 ref-cycles 2.489147029 73,784 cycles 3.490341825 60,720 ref-cycles 3.490341825 37,797 cycles 4.491540887 37,120 ref-cycles 4.491540887 31,963 cycles The example above counts 'cycles' and 'ref-cycles' of BPF program of id 254. This is similar to bpftool-prog-profile command, but more flexible. 'perf stat -b' creates per-cpu perf_event and loads fentry/fexit BPF programs (monitor-progs) to the target BPF program (target-prog). The monitor-progs read perf_event before and after the target-prog, and aggregate the difference in a BPF map. Then the user space reads data from these maps. A new 'struct bpf_counter' is introduced to provide a common interface that uses BPF programs/maps to count perf events. Committer notes: Removed all but bpf_counter.h includes from evsel.h, not needed at all. Also BPF map lookups for PERCPU_ARRAYs need to have as its value receive buffer passed to the kernel libbpf_num_possible_cpus() entries, not evsel__nr_cpus(evsel), as the former uses /sys/devices/system/cpu/possible while the later uses /sys/devices/system/cpu/online, which may be less than the 'possible' number making the bpf map lookup overwrite memory and cause hard to debug memory corruption. We need to continue using evsel__nr_cpus(evsel) when accessing the perf_counts array tho, not to overwrite another are of memory :-) Signed-off-by: Song Liu <songliubraving@fb.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Link: https://lore.kernel.org/lkml/20210120163031.GU12699@kernel.org/ Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: kernel-team@fb.com Link: http://lore.kernel.org/lkml/20201229214214.3413833-4-songliubraving@fb.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>