kernel/tools/perf/builtin-record.c, branch linux-4.16.y

perf record: Fix crash in pipe mode

2018-03-05T14:52:41Z

Currently we can crash perf record when running in pipe mode, like: $ perf record ls | perf report # To display the perf.data header info, please use --header/--header-only options. # perf: Segmentation fault Error: The - file has no samples! The callstack of the crash is: 0x0000000000515242 in perf_event__synthesize_event_update_name 3513 ev = event_update_event__new(len + 1, PERF_EVENT_UPDATE__NAME, evsel->id[0]); (gdb) bt #0 0x0000000000515242 in perf_event__synthesize_event_update_name #1 0x00000000005158a4 in perf_event__synthesize_extra_attr #2 0x0000000000443347 in record__synthesize #3 0x00000000004438e3 in __cmd_record #4 0x000000000044514e in cmd_record #5 0x00000000004cbc95 in run_builtin #6 0x00000000004cbf02 in handle_internal_command #7 0x00000000004cc054 in run_argv #8 0x00000000004cc422 in main The reason of the crash is that the evsel does not have ids array allocated and the pipe's synthesize code tries to access it. We don't force evsel ids allocation when we have single event, because it's not needed. However we need it when we are in pipe mode even for single event as a key for evsel update event. Fixing this by forcing evsel ids allocation event for single event, when we are in pipe mode. Signed-off-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: David Ahern Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20180302161354.30192-1-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf record: Fix period option handling

2018-02-05T15:18:28Z

Stephan reported we don't unset PERIOD sample type when --no-period is specified. Adding the unset check and reset PERIOD if --no-period is specified. Committer notes: Check the sample_type, it shouldn't have PERF_SAMPLE_PERIOD there when --no-period is used. Before: # perf record --no-period sleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.018 MB perf.data (7 samples) ] # perf evlist -v cycles:ppp: size: 112, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|PERIOD, 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 # After: [root@jouet ~]# perf record --no-period sleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.019 MB perf.data (17 samples) ] [root@jouet ~]# perf evlist -v cycles:ppp: size: 112, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME, 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 [root@jouet ~]# Reported-by: Stephane Eranian Signed-off-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Tested-by: Stephane Eranian Cc: Alexander Shishkin Cc: Andi Kleen Cc: David Ahern Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20180201083812.11359-3-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf record: Record the first and last sample time in the header

2018-01-08T14:20:56Z

In the default 'perf record' configuration, all samples are processed, to create the HEADER_BUILD_ID table. So it's very easy to get the first/last samples and save the time to perf file header via the function write_sample_time(). Later, at post processing time, perf report/script will fetch the time from perf file header. Committer testing: # perf record -a sleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 2.099 MB perf.data (1101 samples) ] [root@jouet home]# perf report --header | grep "time of " # time of first sample : 22947.909226 # time of last sample : 22948.910704 # # perf report -D | grep PERF_RECORD_SAMPLE\( 0 22947909226101 0x20bb68 [0x30]: PERF_RECORD_SAMPLE(IP, 0x4001): 0/0: 0xffffffffa21b1af3 period: 1 addr: 0 0 22947909229928 0x20bb98 [0x30]: PERF_RECORD_SAMPLE(IP, 0x4001): 0/0: 0xffffffffa200d204 period: 1 addr: 0 3 22948910397351 0x219360 [0x30]: PERF_RECORD_SAMPLE(IP, 0x4001): 28251/28251: 0xffffffffa22071d8 period: 169518 addr: 0 0 22948910652380 0x20f120 [0x30]: PERF_RECORD_SAMPLE(IP, 0x4001): 0/0: 0xffffffffa2856816 period: 198807 addr: 0 2 22948910704034 0x2172d0 [0x30]: PERF_RECORD_SAMPLE(IP, 0x4001): 0/0: 0xffffffffa2856816 period: 88111 addr: 0 # Changelog: v7: Just update the patch description according to Arnaldo's suggestion. v6: Currently '--buildid-all' is not enabled at default. So the walking on all samples is the default operation. There is no big overhead to calculate the timestamp boundary in process_sample_event handler once we already go through all samples. So the timestamp boundary calculation is enabled by default when '--buildid-all' is not enabled. While if '--buildid-all' is enabled, we creates a new option "--timestamp-boundary" for user to decide if it enables the timestamp boundary calculation. v5: There is an issue that the sample walking can only work when '--buildid-all' is not enabled. So we need to let the walking be able to work even if '--buildid-all' is enabled and let the processing skips the dso hit marking for this case. At first, I want to provide a new option "--record-time-boundaries". While after consideration, I think a new option is not very necessary. v3: Remove the definitions of first_sample_time and last_sample_time from struct record and directly save them in perf_evlist. Signed-off-by: Jin Yao Acked-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Andi Kleen Cc: Kan Liang Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1512738826-2628-3-git-send-email-yao.jin@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf evsel: Enable ignore_missing_thread for pid option

2017-12-27T15:15:58Z

While monitoring a multithread process with pid option, perf sometimes may return sys_perf_event_open failure with 3(No such process) if any of the process's threads die before we open the event. However, we want perf continue monitoring the remaining threads and do not exit with error. Here, the patch enables perf_evsel::ignore_missing_thread for -p option to ignore complete failure if any of threads die before we open the event. But it may still return sys_perf_event_open failure with 22(Invalid) if we monitors several event groups. sys_perf_event_open: pid 28960 cpu 40 group_fd 118202 flags 0x8 sys_perf_event_open: pid 28961 cpu 40 group_fd 118203 flags 0x8 WARNING: Ignored open failure for pid 28962 sys_perf_event_open: pid 28962 cpu 40 group_fd [118203] flags 0x8 sys_perf_event_open failed, error -22 That is because when we ignore a missing thread, we change the thread_idx without dealing with its fds, FD(evsel, cpu, thread). Then get_group_fd() may return a wrong group_fd for the next thread and sys_perf_event_open() return with 22. sys_perf_event_open(){ ... if (group_fd != -1) perf_fget_light()//to get corresponding group_leader by group_fd ... if (group_leader) if (group_leader->ctx->task != ctx->task)//should on the same task goto err_context ... } This patch also fixes this bug by introducing perf_evsel__remove_fd() and update_fds to allow removing fds for the missing thread. Changes since v1: - Change group_fd__remove() into a more genetic way without changing code logic - Remove redundant condition Changes since v2: - Use a proper function name and add some comment. - Multiline comment style fixes. Committer testing: Before this patch the recently added 'perf stat --per-thread' for system wide counting would race while enumerating all threads using /proc: [root@jouet ~]# perf stat --per-thread failed to parse CPUs map: No such file or directory Usage: perf stat [] [] -C, --cpu list of cpus to monitor in system-wide -a, --all-cpus system-wide collection from all CPUs [root@jouet ~]# perf stat --per-thread failed to parse CPUs map: No such file or directory Usage: perf stat [] [] -C, --cpu list of cpus to monitor in system-wide -a, --all-cpus system-wide collection from all CPUs [root@jouet ~]# When, say, the kernel was being built, so lots of shortlived threads, after this patch this doesn't happen. Signed-off-by: Mengting Zhang Tested-by: Arnaldo Carvalho de Melo Acked-by: Jiri Olsa Cc: Cheng Jian Cc: Li Bin Cc: Wang Nan Link: http://lkml.kernel.org/r/1513148513-6974-1-git-send-email-zhangmengting@huawei.com [ Remove one use 'evlist' alias variable ] Signed-off-by: Arnaldo Carvalho de Melo

perf perf: Remove duplicate includes

2017-12-27T15:15:49Z

These duplicate includes have been found with scripts/checkincludes.pl but they have been removed manually to avoid removing false positives. Signed-off-by: Pravin Shedge Cc: David S. Miller Cc: Greg Kroah-Hartman Cc: Jiri Olsa Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1512582204-6493-1-git-send-email-pravin.shedge4linux@gmail.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Rename 'backward' to 'overwrite' in evlist, mmap and record

2017-12-05T19:02:39Z

Remove the backward/forward concept to make it uniform with user interface (the '--overwrite' option). Signed-off-by: Wang Nan Acked-by: Namhyung Kim Cc: Jiri Olsa Cc: Kan Liang Cc: Mengting Zhang Link: http://lkml.kernel.org/r/20171204165107.95327-4-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf mmap: Remove overwrite from arguments list of perf_mmap__push

2017-12-05T18:43:54Z

'overwrite' argument is always 'false'. Remove it from arguments list of perf_mmap__push(). Signed-off-by: Wang Nan Acked-by: Namhyung Kim Cc: Jiri Olsa Cc: Kan Liang Link: http://lkml.kernel.org/r/20171203020044.81680-5-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Remove evlist->overwrite

2017-12-05T18:43:54Z

evlist->overwrite is set to false in all users. It can be removed. Signed-off-by: Wang Nan Acked-by: Namhyung Kim Cc: Jiri Olsa Cc: Kan Liang Link: http://lkml.kernel.org/r/20171203020044.81680-4-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Remove 'overwrite' parameter from perf_evlist__mmap_ex

2017-12-05T18:43:53Z

All users of perf_evlist__mmap_ex set !overwrite. Remove it from its arguments list. Signed-off-by: Wang Nan Acked-by: Namhyung Kim Cc: Jiri Olsa Cc: Kan Liang Link: http://lkml.kernel.org/r/20171203020044.81680-3-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf record: Synthesize thread map and cpu map

2017-11-29T21:18:00Z

Synthesize the per attr thread maps and cpu maps in 'perf record'. This allows code from 'perf stat' called from 'perf script' to access this information. Committer testing: Please see the PERF_RECORD_THREAD_MAP and PERF_RECORD_CPU_MAP records, added by this patch: $ perf record sleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.001 MB perf.data (8 samples) ] $ perf report -D | grep PERF_RECORD_ | head 0xe8 [0x20]: PERF_RECORD_TIME_CONV: unhandled! 0x108 [0x28]: PERF_RECORD_THREAD_MAP nr: 1 thread: 23568 0x130 [0x18]: PERF_RECORD_CPU_MAP: 0-3 0 0x148 [0x28]: PERF_RECORD_COMM: perf:23568/23568 0x570 [0x8]: PERF_RECORD_FINISHED_ROUND 445342677837144 0x170 [0x28]: PERF_RECORD_COMM exec: sleep:23568/23568 445342677847339 0x198 [0x68]: PERF_RECORD_MMAP2 23568/23568: [0x564c943a4000(0x208000) @ 0 fd:00 3147174 2566255743]: r-xp /usr/bin/sleep 445342677862450 0x200 [0x70]: PERF_RECORD_MMAP2 23568/23568: [0x7f25968a8000(0x229000) @ 0 fd:00 3151761 2566238119]: r-xp /usr/lib64/ld-2.25.so 445342677873174 0x270 [0x60]: PERF_RECORD_MMAP2 23568/23568: [0x7ffc98176000(0x2000) @ 0 00:00 0 0]: r-xp [vdso] 445342677891928 0x2d0 [0x28]: PERF_RECORD_SAMPLE(IP, 0x4002): 23568/23568: 0xffffffff8f84c7e7 period: 1 addr: 0 $ Signed-off-by: Andi Kleen Acked-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Link: http://lkml.kernel.org/r/20171117214300.32746-3-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo