kernel.git/tools/perf/builtin-record.c, branch linux-5.10.y

perf record: Fix incorrect --user-regs comments

2025-06-27T10:04:06Z

[ Upstream commit a4a859eb6704a8aa46aa1cec5396c8d41383a26b ] The comment of "--user-regs" option is not correct, fix it. "on interrupt," -> "in user space," Fixes: 84c417422798c897 ("perf record: Support direct --user-regs arguments") Reviewed-by: Ian Rogers Signed-off-by: Dapeng Mi Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Ingo Molnar Cc: Kan Liang Cc: Namhyung Kim Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20250403060810.196028-1-dapeng1.mi@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf record: Fix possible incorrect free in record__switch_output()

2024-03-26T22:21:55Z

[ Upstream commit aff10a165201f6f60cff225083ce301ad3f5d8f1 ] perf_data__switch() may not assign a legal value to 'new_filename'. In this case, 'new_filename' uses the on-stack value, which may cause a incorrect free and unexpected result. Fixes: 03724b2e9c45 ("perf record: Allow to limit number of reported perf.data files") Signed-off-by: Yang Jihong Acked-by: Namhyung Kim Link: https://lore.kernel.org/r/20240119040304.3708522-2-yangjihong1@huawei.com Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin

perf record: Fix continue profiling after draining the buffer

2021-03-04T10:38:09Z

[ Upstream commit e16c2ce7c5ed5de881066c1fd10ba5c09af69559 ] Commit da231338ec9c0987 ("perf record: Use an eventfd to wakeup when done") uses eventfd() to solve a rare race where the setting and checking of 'done' which add done_fd to pollfd. When draining buffer, revents of done_fd is 0 and evlist__filter_pollfd function returns a non-zero value. As a result, perf record does not stop profiling. The following simple scenarios can trigger this condition: # sleep 10 & # perf record -p $! After the sleep process exits, perf record should stop profiling and exit. However, perf record keeps running. If pollfd revents contains only POLLERR or POLLHUP, perf record indicates that buffer is draining and need to stop profiling. Use fdarray_flag__nonfilterable() to set done eventfd to nonfilterable objects, so that evlist__filter_pollfd() does not filter and check done eventfd. Fixes: da231338ec9c0987 ("perf record: Use an eventfd to wakeup when done") Signed-off-by: Yang Jihong Tested-by: Arnaldo Carvalho de Melo Tested-by: Jiri Olsa Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexey Budankov Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: zhangjinhao2@huawei.com Link: http://lore.kernel.org/lkml/20210205065001.23252-1-yangjihong1@huawei.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf tools: Consolidate close_control_option()'s into one function

2020-09-04T19:11:16Z

Consolidate control option fifo closing into one function. Signed-off-by: Adrian Hunter Suggested-by: Alexey Budankov Cc: Andi Kleen Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lore.kernel.org/lkml/20200903122937.25691-1-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf record: Add 'snapshot' control command

2020-09-04T17:38:15Z

Add 'snapshot' control command to create an AUX area tracing snapshot the same as if sending SIGUSR2. The advantage of the FIFO is that access is governed by access to the FIFO. Example: $ mkfifo perf.control $ mkfifo perf.ack $ cat perf.ack & [1] 15235 $ sudo ~/bin/perf record --control fifo:perf.control,perf.ack -S -e intel_pt//u -- sleep 60 & [2] 15243 $ ps -e | grep perf 15244 pts/1 00:00:00 perf $ kill -USR2 15244 bash: kill: (15244) - Operation not permitted $ echo snapshot > perf.control ack $ Signed-off-by: Adrian Hunter Acked-by: Alexey Budankov Acked-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Cc: Andi Kleen Cc: Namhyung Kim Link: http://lore.kernel.org/lkml/20200901093758.32293-6-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add FIFO file names as alternative options to --control

2020-09-04T17:38:15Z

Enable the --control option to accept file names as an alternative to file descriptors. Example: $ mkfifo perf.control $ mkfifo perf.ack $ cat perf.ack & [1] 6808 $ perf record --control fifo:perf.control,perf.ack -- sleep 300 & [2] 6810 $ echo disable > perf.control $ Events disabled ack $ echo enable > perf.control $ Events enabled ack $ echo disable > perf.control $ Events disabled ack $ kill %2 [ perf record: Woken up 4 times to write data ] $ [ perf record: Captured and wrote 0.018 MB perf.data (7 samples) ] [1]- Done cat perf.ack [2]+ Terminated perf record --control fifo:perf.control,perf.ack -- sleep 300 $ Signed-off-by: Adrian Hunter Acked-by: Alexey Budankov Acked-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Cc: Andi Kleen Cc: Namhyung Kim Link: http://lore.kernel.org/lkml/20200902105707.11491-1-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Consolidate --control option parsing into one function

2020-09-04T17:38:15Z

Consolidate --control option parsing into one function, in preparation for adding FIFO file name options. Signed-off-by: Adrian Hunter Acked-by: Alexey Budankov Acked-by: Jiri Olsa Cc: Andi Kleen Cc: Namhyung Kim Link: http://lore.kernel.org/lkml/20200901093758.32293-2-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf record: Correct the help info of option "--no-bpf-event"

2020-09-01T15:15:51Z

The help info of option "--no-bpf-event" is wrongly described as "record bpf events", correct it. Committer testing: $ perf record -h bpf Usage: perf record [] [] or: perf record [] -- [] --clang-opt options passed to clang when compiling BPF scriptlets --clang-path clang binary to use for compiling BPF scriptlets --no-bpf-event do not record bpf events $ Fixes: 71184c6ab7e6 ("perf record: Replace option --bpf-event with --no-bpf-event") Signed-off-by: Wei Li Acked-by: Song Liu Tested-by: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Hanjun Guo Cc: Jiri Olsa Cc: Li Bin Cc: Mark Rutland Cc: Namhyung Kim Link: http://lore.kernel.org/lkml/20200819031947.12115-1-liwei391@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf record: Skip side-band event setup if HAVE_LIBBPF_SUPPORT is not set

2020-08-07T12:27:03Z

We received an error report that perf-record caused 'Segmentation fault' on a newly system (e.g. on the new installed ubuntu). (gdb) backtrace #0 __read_once_size (size=4, res=, p=0x14) at /root/0-jinyao/acme/tools/include/linux/compiler.h:139 #1 atomic_read (v=0x14) at /root/0-jinyao/acme/tools/include/asm/../../arch/x86/include/asm/atomic.h:28 #2 refcount_read (r=0x14) at /root/0-jinyao/acme/tools/include/linux/refcount.h:65 #3 perf_mmap__read_init (map=map@entry=0x0) at mmap.c:177 #4 0x0000561ce5c0de39 in perf_evlist__poll_thread (arg=0x561ce68584d0) at util/sideband_evlist.c:62 #5 0x00007fad78491609 in start_thread (arg=) at pthread_create.c:477 #6 0x00007fad7823c103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95 The root cause is, evlist__add_bpf_sb_event() just returns 0 if HAVE_LIBBPF_SUPPORT is not defined (inline function path). So it will not create a valid evsel for side-band event. But perf-record still creates BPF side band thread to process the side-band event, then the error happpens. We can reproduce this issue by removing the libelf-dev. e.g. 1. apt-get remove libelf-dev 2. perf record -a -- sleep 1 root@test:~# ./perf record -a -- sleep 1 perf: Segmentation fault Obtained 6 stack frames. ./perf(+0x28eee8) [0x5562d6ef6ee8] /lib/x86_64-linux-gnu/libc.so.6(+0x46210) [0x7fbfdc65f210] ./perf(+0x342e74) [0x5562d6faae74] ./perf(+0x257e39) [0x5562d6ebfe39] /lib/x86_64-linux-gnu/libpthread.so.0(+0x9609) [0x7fbfdc990609] /lib/x86_64-linux-gnu/libc.so.6(clone+0x43) [0x7fbfdc73b103] Segmentation fault (core dumped) To fix this issue, 1. We either install the missing libraries to let HAVE_LIBBPF_SUPPORT be defined. e.g. apt-get install libelf-dev and install other related libraries. 2. Use this patch to skip the side-band event setup if HAVE_LIBBPF_SUPPORT is not set. Committer notes: The side band thread is not used just with BPF, it is also used with --switch-output-event, so narrow the ifdef to the BPF specific part. Fixes: 23cbb41c939a ("perf record: Move side band evlist setup to separate routine") Signed-off-by: Jin Yao Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: Andi Kleen Cc: Jin Yao Cc: Kan Liang Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20200805022937.29184-1-yao.jin@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Move clockid_res_ns under clock struct

2020-08-06T12:42:20Z

Move the clockid_res_ns struct member to the clock struct, so we have the clock related stuff in one place. Signed-off-by: Jiri Olsa Cc: Alexander Shishkin Cc: Andi Kleen Cc: David Ahern Cc: Geneviève Bastien Cc: Ian Rogers Cc: Jeremie Galarneau Cc: Michael Petlan Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Wang Nan Link: http://lore.kernel.org/lkml/20200805093444.314999-5-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo