kernel/tools/perf/util/evsel.c, branch linux-5.1.y

perf evsel: Make perf_evsel__name() accept a NULL argument

2019-07-26T07:12:36Z

[ Upstream commit fdbdd7e8580eac9bdafa532746c865644d125e34 ] In which case it simply returns "unknown", like when it can't figure out the evsel->name value. This makes this code more robust and fixes a problem in 'perf trace' where a NULL evsel was being passed to a routine that only used the evsel for printing its name when a invalid syscall id was passed. Reported-by: Leo Yan Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-f30ztaasku3z935cn3ak3h53@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf evsel: Use hweight64() instead of hweight_long(attr.sample_regs_user)

2019-04-16T14:27:53Z

On 32-bits platform with more than 32 registers, the 64 bits mask is truncate to the lower 32 bits and the return value of hweight_long will always smaller than 32. When kernel outputs more than 32 registers, but the user perf program only counts 32, there will be a data mismatch result to overflow check fail. Signed-off-by: Mao Han Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Fixes: 6a21c0b5c2ab ("perf tools: Add core support for sampling intr machine state regs") Fixes: d03f2170546d ("perf tools: Expand perf_event__synthesize_sample()") Fixes: 0f6a30150ca2 ("perf tools: Support user regs and stack in sample parsing") Link: http://lkml.kernel.org/r/29ad7947dc8fd1ff0abd2093a72cc27a2446be9f.1554883878.git.han_mao@c-sky.com Signed-off-by: Arnaldo Carvalho de Melo

perf evsel: Fix max perf_event_attr.precise_ip detection

2019-03-28T17:31:56Z

After a discussion with Andi, move the perf_event_attr.precise_ip detection for maximum precise config (via :P modifier or for default cycles event) to perf_evsel__open(). The current detection in perf_event_attr__set_max_precise_ip() is tricky, because precise_ip config is specific for given event and it currently checks only hw cycles. We now check for valid precise_ip value right after failing sys_perf_event_open() for specific event, before any of the perf_event_attr fallback code gets executed. This way we get the proper config in perf_event_attr together with allowed precise_ip settings. We can see that code activity with -vv, like: $ perf record -vv ls ... ------------------------------------------------------------ perf_event_attr: size 112 { sample_period, sample_freq } 4000 ... precise_ip 3 sample_id_all 1 exclude_guest 1 mmap2 1 comm_exec 1 ksymbol 1 ------------------------------------------------------------ sys_perf_event_open: pid 9926 cpu 0 group_fd -1 flags 0x8 sys_perf_event_open failed, error -95 decreasing precise_ip by one (2) ------------------------------------------------------------ perf_event_attr: size 112 { sample_period, sample_freq } 4000 ... precise_ip 2 sample_id_all 1 exclude_guest 1 mmap2 1 comm_exec 1 ksymbol 1 ------------------------------------------------------------ sys_perf_event_open: pid 9926 cpu 0 group_fd -1 flags 0x8 = 4 ... Suggested-by: Andi Kleen Signed-off-by: Jiri Olsa Link: http://lkml.kernel.org/n/tip-dkvxxbeg7lu74155d4jhlmc9@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf record: Replace option --bpf-event with --no-bpf-event

2019-03-19T19:52:06Z

Currently, monitoring of BPF programs through bpf_event is off by default for 'perf record'. To turn it on, the user need to use option "--bpf-event". As BPF gets wider adoption in different subsystems, this option becomes inconvenient. This patch makes bpf_event on by default, and adds option "--no-bpf-event" to turn it off. Since option --bpf-event is not released yet, it is safe to remove it. Signed-off-by: Song Liu Reviewed-by: Jiri Olsa Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: kernel-team@fb.com Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stanislav Fomichev Link: http://lkml.kernel.org/r/20190312053051.2690567-2-songliubraving@fb.com Signed-off-by: Arnaldo Carvalho de Melo

perf evsel: Free evsel->counts in perf_evsel__exit()

2019-03-19T19:52:05Z

Using gcc's ASan, Changbin reports: ================================================================= ==7494==ERROR: LeakSanitizer: detected memory leaks Direct leak of 48 byte(s) in 1 object(s) allocated from: #0 0x7f0333a89138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138) #1 0x5625e5330a5e in zalloc util/util.h:23 #2 0x5625e5330a9b in perf_counts__new util/counts.c:10 #3 0x5625e5330ca0 in perf_evsel__alloc_counts util/counts.c:47 #4 0x5625e520d8e5 in __perf_evsel__read_on_cpu util/evsel.c:1505 #5 0x5625e517a985 in perf_evsel__read_on_cpu /home/work/linux/tools/perf/util/evsel.h:347 #6 0x5625e517ad1a in test__openat_syscall_event tests/openat-syscall.c:47 #7 0x5625e51528e6 in run_test tests/builtin-test.c:358 #8 0x5625e5152baf in test_and_print tests/builtin-test.c:388 #9 0x5625e51543fe in __cmd_test tests/builtin-test.c:583 #10 0x5625e515572f in cmd_test tests/builtin-test.c:722 #11 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302 #12 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354 #13 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398 #14 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520 #15 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a) Indirect leak of 72 byte(s) in 1 object(s) allocated from: #0 0x7f0333a89138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138) #1 0x5625e532560d in zalloc util/util.h:23 #2 0x5625e532566b in xyarray__new util/xyarray.c:10 #3 0x5625e5330aba in perf_counts__new util/counts.c:15 #4 0x5625e5330ca0 in perf_evsel__alloc_counts util/counts.c:47 #5 0x5625e520d8e5 in __perf_evsel__read_on_cpu util/evsel.c:1505 #6 0x5625e517a985 in perf_evsel__read_on_cpu /home/work/linux/tools/perf/util/evsel.h:347 #7 0x5625e517ad1a in test__openat_syscall_event tests/openat-syscall.c:47 #8 0x5625e51528e6 in run_test tests/builtin-test.c:358 #9 0x5625e5152baf in test_and_print tests/builtin-test.c:388 #10 0x5625e51543fe in __cmd_test tests/builtin-test.c:583 #11 0x5625e515572f in cmd_test tests/builtin-test.c:722 #12 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302 #13 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354 #14 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398 #15 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520 #16 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a) His patch took care of evsel->prev_raw_counts, but the above backtraces are about evsel->counts, so fix that instead. Reported-by: Changbin Du Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Steven Rostedt (VMware) Link: https://lkml.kernel.org/n/tip-hd1x13g59f0nuhe4anxhsmfp@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Improve scaling

2019-03-19T19:52:03Z

The multiplexing scaling in perf stat mysteriously adds 0.5 to the value. This dates back to the original perf tool. Other scaling code doesn't use that strange convention. Remove the extra 0.5. Before: $ perf stat -e 'cycles,cycles,cycles,cycles,cycles,cycles' grep -rq foo Performance counter stats for 'grep -rq foo': 6,403,580 cycles (81.62%) 6,404,341 cycles (81.64%) 6,402,983 cycles (81.62%) 6,399,941 cycles (81.63%) 6,399,451 cycles (81.62%) 6,436,105 cycles (91.87%) 0.005843799 seconds time elapsed 0.002905000 seconds user 0.002902000 seconds sys After: $ perf stat -e 'cycles,cycles,cycles,cycles,cycles,cycles' grep -rq foo Performance counter stats for 'grep -rq foo': 6,422,704 cycles (81.68%) 6,401,842 cycles (81.68%) 6,398,432 cycles (81.68%) 6,397,098 cycles (81.68%) 6,396,074 cycles (81.67%) 6,434,980 cycles (91.62%) 0.005884437 seconds time elapsed 0.003580000 seconds user 0.002356000 seconds sys Signed-off-by: Andi Kleen Acked-by: Jiri Olsa LPU-Reference: 20190314225002.30108-10-andi@firstfloor.org Tested-by: Arnaldo Carvalho de Melo Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Fix --no-scale

2019-03-19T19:52:03Z

The -c option to enable multiplex scaling has been useless for quite some time because scaling is default. It's only useful as --no-scale to disable scaling. But the non scaling code path has bitrotted and doesn't print anything because perf output code relies on value run/ena information. Also even when we don't want to scale a value it's still useful to show its multiplex percentage. This patch: - Fixes help and documentation to show --no-scale instead of -c - Removes -c, only keeps the long option because -c doesn't support negatives. - Enables running/enabled even with --no-scale - And fixes some other problems in the no-scale output. Before: $ perf stat --no-scale -e cycles true Performance counter stats for 'true': cycles 0.000984154 seconds time elapsed After: $ ./perf stat --no-scale -e cycles true Performance counter stats for 'true': 706,070 cycles 0.001219821 seconds time elapsed Signed-off-by: Andi Kleen Acked-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo LPU-Reference: 20190314225002.30108-9-andi@firstfloor.org Link: https://lkml.kernel.org/n/tip-xggjvwcdaj2aqy8ib3i4b1g6@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf evsel: Probe for precise_ip with simple attr

2019-03-06T21:19:45Z

Currently we probe for precise_ip with user specified perf_event_attr, which might fail because of unsupported kernel features, which would get disabled during the open time anyway. Switching the probe to take place on simple hw cycles, so the following record sets proper precise_ip: # perf record -e cycles:P ls # perf evlist -v cycles:P: size: 112, ... precise_ip: 3, ... Signed-off-by: Jiri Olsa Cc: Alexander Shishkin Cc: Andi Kleen Cc: Jonas Rabenstein Cc: Nageswara R Sastry Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Ravi Bangoria Link: http://lkml.kernel.org/r/20190305152536.21035-7-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf evsel: Force sample_type for slave events

2019-02-20T19:08:59Z

Force sample_type setup for slave events in group leader sessions. We don't get sample for slave events, we make them when delivering group leader sample. Set the slave event to follow the master sample_type to ease up report. Signed-off-by: Jiri Olsa Cc: Alexander Shishkin Cc: Andi Kleen Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20190220122800.864-3-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Handle PERF_RECORD_BPF_EVENT

2019-01-21T20:00:57Z

This patch adds basic handling of PERF_RECORD_BPF_EVENT. Tracking of PERF_RECORD_BPF_EVENT is OFF by default. Option --bpf-event is added to turn it on. Committer notes: Add dummy machine__process_bpf_event() variant that returns zero for systems without HAVE_LIBBPF_SUPPORT, such as Alpine Linux, unbreaking the build in such systems. Remove the needless include from bpf->event.h, provide just forward declarations for the structs and unions in the parameters, to reduce compilation time and needless rebuilds when machine.h gets changed. Committer testing: When running with: # perf record --bpf-event On an older kernel where PERF_RECORD_BPF_EVENT and PERF_RECORD_KSYMBOL is not present, we fallback to removing those two bits from perf_event_attr, making the tool to continue to work on older kernels: perf_event_attr: size 112 { sample_period, sample_freq } 4000 sample_type IP|TID|TIME|PERIOD read_format ID disabled 1 inherit 1 mmap 1 comm 1 freq 1 enable_on_exec 1 task 1 precise_ip 3 sample_id_all 1 exclude_guest 1 mmap2 1 comm_exec 1 ksymbol 1 bpf_event 1 ------------------------------------------------------------ sys_perf_event_open: pid 5779 cpu 0 group_fd -1 flags 0x8 sys_perf_event_open failed, error -22 switching off bpf_event ------------------------------------------------------------ perf_event_attr: size 112 { sample_period, sample_freq } 4000 sample_type IP|TID|TIME|PERIOD read_format ID disabled 1 inherit 1 mmap 1 comm 1 freq 1 enable_on_exec 1 task 1 precise_ip 3 sample_id_all 1 exclude_guest 1 mmap2 1 comm_exec 1 ksymbol 1 ------------------------------------------------------------ sys_perf_event_open: pid 5779 cpu 0 group_fd -1 flags 0x8 sys_perf_event_open failed, error -22 switching off ksymbol ------------------------------------------------------------ perf_event_attr: size 112 { sample_period, sample_freq } 4000 sample_type IP|TID|TIME|PERIOD read_format ID disabled 1 inherit 1 mmap 1 comm 1 freq 1 enable_on_exec 1 task 1 precise_ip 3 sample_id_all 1 exclude_guest 1 mmap2 1 comm_exec 1 ------------------------------------------------------------ And then proceeds to work without those two features. As passing --bpf-event is an explicit action performed by the user, perhaps we should emit a warning telling that the kernel has no such feature, but this can be done on top of this patch. Now with a kernel that supports these events, start the 'record --bpf-event -a' and then run 'perf trace sleep 10000' that will use the BPF augmented_raw_syscalls.o prebuilt (for another kernel version even) and thus should generate PERF_RECORD_BPF_EVENT events: [root@quaco ~]# perf record -e dummy -a --bpf-event ^C[ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.713 MB perf.data ] [root@quaco ~]# bpftool prog 13: cgroup_skb tag 7be49e3934a125ba gpl loaded_at 2019-01-19T09:09:43-0300 uid 0 xlated 296B jited 229B memlock 4096B map_ids 13,14 14: cgroup_skb tag 2a142ef67aaad174 gpl loaded_at 2019-01-19T09:09:43-0300 uid 0 xlated 296B jited 229B memlock 4096B map_ids 13,14 15: cgroup_skb tag 7be49e3934a125ba gpl loaded_at 2019-01-19T09:09:43-0300 uid 0 xlated 296B jited 229B memlock 4096B map_ids 15,16 16: cgroup_skb tag 2a142ef67aaad174 gpl loaded_at 2019-01-19T09:09:43-0300 uid 0 xlated 296B jited 229B memlock 4096B map_ids 15,16 17: cgroup_skb tag 7be49e3934a125ba gpl loaded_at 2019-01-19T09:09:44-0300 uid 0 xlated 296B jited 229B memlock 4096B map_ids 17,18 18: cgroup_skb tag 2a142ef67aaad174 gpl loaded_at 2019-01-19T09:09:44-0300 uid 0 xlated 296B jited 229B memlock 4096B map_ids 17,18 21: cgroup_skb tag 7be49e3934a125ba gpl loaded_at 2019-01-19T09:09:45-0300 uid 0 xlated 296B jited 229B memlock 4096B map_ids 21,22 22: cgroup_skb tag 2a142ef67aaad174 gpl loaded_at 2019-01-19T09:09:45-0300 uid 0 xlated 296B jited 229B memlock 4096B map_ids 21,22 31: tracepoint name sys_enter tag 12504ba9402f952f gpl loaded_at 2019-01-19T09:19:56-0300 uid 0 xlated 512B jited 374B memlock 4096B map_ids 30,29,28 32: tracepoint name sys_exit tag c1bd85c092d6e4aa gpl loaded_at 2019-01-19T09:19:56-0300 uid 0 xlated 256B jited 191B memlock 4096B map_ids 30,29 # perf report -D | grep PERF_RECORD_BPF_EVENT | nl 1 0 55834574849 0x4fc8 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 13 2 0 60129542145 0x5118 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 14 3 0 64424509441 0x5268 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 15 4 0 68719476737 0x53b8 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 16 5 0 73014444033 0x5508 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 17 6 0 77309411329 0x5658 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 18 7 0 90194313217 0x57a8 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 21 8 0 94489280513 0x58f8 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 22 9 7 620922484360 0xb6390 [0x30]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 29 10 7 620922486018 0xb6410 [0x30]: PERF_RECORD_BPF_EVENT bpf event with type 2, flags 0, id 29 11 7 620922579199 0xb6490 [0x30]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 30 12 7 620922580240 0xb6510 [0x30]: PERF_RECORD_BPF_EVENT bpf event with type 2, flags 0, id 30 13 7 620922765207 0xb6598 [0x30]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 31 14 7 620922874543 0xb6620 [0x30]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 32 # There, the 31 and 32 tracepoint BPF programs put in place by 'perf trace'. Signed-off-by: Song Liu Reviewed-by: Arnaldo Carvalho de Melo Tested-by: Arnaldo Carvalho de Melo Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: Peter Zijlstra Cc: kernel-team@fb.com Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/20190117161521.1341602-7-songliubraving@fb.com Signed-off-by: Arnaldo Carvalho de Melo