kernel/linux.git/tools/perf/util/event.c, branch v5.16

perf tools: Add support for PERF_RECORD_AUX_OUTPUT_HW_ID

2021-10-20T14:22:27+00:00

The PERF_RECORD_AUX_OUTPUT_HW_ID event provides a way to match AUX output data like Intel PT PEBS-via-PT back to the event that it came from, by providing a hardware ID that is present in the AUX output. Reviewed-by: Alexander Shishkin Reviewed-by: Andi Kleen Signed-off-by: Adrian Hunter Cc: Jiri Olsa Cc: Kan Liang Cc: Leo Yan Cc: Mark Rutland Cc: Peter Zijlstra Cc: x86@kernel.org Link: http://lore.kernel.org/lkml/20210907163903.11820-3-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf script: Support filtering by hex address

2021-02-08T20:09:11+00:00

'perf script' supports '-S' or '--symbol' options to only list the records for these symbols. A symbol is typically a name or hex address. If it's hex address, it is the start address of one symbol. While it would be useful if we can filter trace records by any hex address (not only the start address of symbol). So now we support filtering trace records by more conditions, such as: - symbol name - start address of symbol - any hexadecimal address - address range The comparison order is defined as: 1. symbol name comparison 2. symbol start address comparison. 3. any hexadecimal address comparison. 4. address range comparison. The idea is if we can get a valid address from -S list, we add the address to addr_list for address comparison otherwise we still leave it to sym_list for symbol comparison. Some examples: root@kbl-ppc:~# ./perf script -S ffffffff9a477308 perf 8562 [000] 347303.578858: 1 cycles: ffffffff9a477308 native_write_msr+0x8 ([kernel.kallsyms]) perf 8562 [000] 347303.578860: 1 cycles: ffffffff9a477308 native_write_msr+0x8 ([kernel.kallsyms]) perf 8562 [000] 347303.578861: 11 cycles: ffffffff9a477308 native_write_msr+0x8 ([kernel.kallsyms]) perf 8562 [001] 347303.578903: 1 cycles: ffffffff9a477308 native_write_msr+0x8 ([kernel.kallsyms]) perf 8562 [001] 347303.578905: 1 cycles: ffffffff9a477308 native_write_msr+0x8 ([kernel.kallsyms]) perf 8562 [001] 347303.578906: 15 cycles: ffffffff9a477308 native_write_msr+0x8 ([kernel.kallsyms]) perf 8562 [002] 347303.578952: 1 cycles: ffffffff9a477308 native_write_msr+0x8 ([kernel.kallsyms]) perf 8562 [002] 347303.578953: 1 cycles: ffffffff9a477308 native_write_msr+0x8 ([kernel.kallsyms]) Filter the traced records by hex address ffffffff9a477308. root@kbl-ppc:~# ./perf script -S ffffffff9a4dd4ce,ffffffff9a4d2de9,ffffffff9a6bf9f4 perf 8562 [001] 347303.578911: 311706 cycles: ffffffff9a6bf9f4 __kmalloc_node+0x204 ([kernel.kallsyms]) perf 8562 [002] 347303.578960: 354477 cycles: ffffffff9a4d2de9 sched_setaffinity+0x49 ([kernel.kallsyms]) perf 8562 [003] 347303.579015: 450958 cycles: ffffffff9a4dd4ce dequeue_task_fair+0x1ae ([kernel.kallsyms]) Filter the traced records by hex address ffffffff9a4dd4ce, ffffffff9a4d2de9, ffffffff9a6bf9f4. root@kbl-ppc:~# ./perf script -S ffffffff9a477309 --addr-range 16 perf 8562 [000] 347303.578863: 291 cycles: ffffffff9a47730a native_write_msr+0xa ([kernel.kallsyms]) perf 8562 [001] 347303.578907: 411 cycles: ffffffff9a47730a native_write_msr+0xa ([kernel.kallsyms]) perf 8562 [002] 347303.578956: 462 cycles: ffffffff9a47730f native_write_msr+0xf ([kernel.kallsyms]) perf 8562 [003] 347303.579010: 497 cycles: ffffffff9a47730f native_write_msr+0xf ([kernel.kallsyms]) perf 8562 [004] 347303.579059: 429 cycles: ffffffff9a47730f native_write_msr+0xf ([kernel.kallsyms]) perf 8562 [005] 347303.579109: 408 cycles: ffffffff9a47730a native_write_msr+0xa ([kernel.kallsyms]) perf 8562 [006] 347303.579159: 460 cycles: ffffffff9a47730f native_write_msr+0xf ([kernel.kallsyms]) perf 8562 [007] 347303.579213: 436 cycles: ffffffff9a47730f native_write_msr+0xf ([kernel.kallsyms]) Filter the traced records from address range [ffffffff9a477309, ffffffff9a477309 + 15]. root@kbl-ppc:~# ./perf script -S "ffffffff9b163046,rcu_nmi_exit" perf 8562 [004] 347303.579060: 12013 cycles: ffffffff9b163046 exc_nmi+0x166 ([kernel.kallsyms]) perf 8562 [007] 347303.579214: 12138 cycles: ffffffff9b165944 rcu_nmi_exit+0x34 ([kernel.kallsyms]) Filter by address + symbol Signed-off-by: Jin Yao Tested-by: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Andi Kleen Cc: Jin Yao Cc: Jiri Olsa Cc: Kan Liang Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20210207080935.31784-2-yao.jin@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Fix DSO filtering when not finding a map for a sampled address

2021-02-03T16:10:43+00:00

When we lookup an address and don't find a map we should filter that sample if the user specified a list of --dso entries to filter on, fix it. Before: $ perf script sleep 274800 2843.556162: 1 cycles:u: ffffffffbb26bff4 [unknown] ([unknown]) sleep 274800 2843.556168: 1 cycles:u: ffffffffbb2b047d [unknown] ([unknown]) sleep 274800 2843.556171: 1 cycles:u: ffffffffbb2706b2 [unknown] ([unknown]) sleep 274800 2843.556174: 6 cycles:u: ffffffffbb2b0267 [unknown] ([unknown]) sleep 274800 2843.556176: 59 cycles:u: ffffffffbb2b03b1 [unknown] ([unknown]) sleep 274800 2843.556180: 691 cycles:u: ffffffffbb26bff4 [unknown] ([unknown]) sleep 274800 2843.556189: 9160 cycles:u: 7fa9550eeaa3 __GI___tunables_init+0xf3 (/usr/lib64/ld-2.32.so) sleep 274800 2843.556312: 86937 cycles:u: 7fa9550e157b _dl_lookup_symbol_x+0x4b (/usr/lib64/ld-2.32.so) $ So we have some samples we somehow didn't find in a map for, if we now do: $ perf report --stdio --dso /usr/lib64/ld-2.32.so # dso: /usr/lib64/ld-2.32.so # # Total Lost Samples: 0 # # Samples: 8 of event 'cycles:u' # Event count (approx.): 96856 # # Overhead Command Symbol # ........ ....... ........................ # 89.76% sleep [.] _dl_lookup_symbol_x 9.46% sleep [.] __GI___tunables_init 0.71% sleep [k] 0xffffffffbb26bff4 0.06% sleep [k] 0xffffffffbb2b03b1 0.01% sleep [k] 0xffffffffbb2b0267 0.00% sleep [k] 0xffffffffbb2706b2 0.00% sleep [k] 0xffffffffbb2b047d $ After this patch we get the right output with just entries for the DSOs specified in --dso: $ perf report --stdio --dso /usr/lib64/ld-2.32.so # dso: /usr/lib64/ld-2.32.so # # Total Lost Samples: 0 # # Samples: 8 of event 'cycles:u' # Event count (approx.): 96856 # # Overhead Command Symbol # ........ ....... ........................ # 89.76% sleep [.] _dl_lookup_symbol_x 9.46% sleep [.] __GI___tunables_init $ # Fixes: 96415e4d3f5fdf9c ("perf symbols: Avoid unnecessary symbol loading when dso list is specified") Cc: Alexander Shishkin Cc: Andi Kleen Cc: Ingo Molnar Cc: Jin Yao Cc: Jiri Olsa Cc: Kan Liang Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20210128131209.GD775562@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add support to display build ids when available in PERF_RECORD_MMAP2 events

2020-12-28T14:36:52+00:00

Add support to display the build id in PERF_RECORD_MMAP2 events, when available: $ perf script --show-mmap-events | head -4 swapper ... @ 0xffffffff81000000 ]: ---p [kernel.kallsyms]_text swapper ... @ 0 <5f62adb730272c9417883ae8b8a8ec224df8cddd>]: ---p /lib/modules/5.9.0-rc5buildid+/kernel/drivers/firmware/qemu_fw_cfg.ko swapper ... @ 0 ]: ---p /lib/modules/5.9.0-rc5buildid+/kernel/drivers/char/virtio_console.ko swapper ... @ 0 <86441a4c5b2c2ff5b440682f4c612bd4b426eb5c>]: ---p /lib/modules/5.9.0-rc5buildid+/kernel/lib/libcrc32c.ko $ perf report -D | grep MMAP2 | head -4 0 0 ... @ 0xffffffff81000000 ]: ---p [kernel.kallsyms]_text 0 0 ... @ 0 <5f62adb730272c9417883ae8b8a8ec224df8cddd>]: ---p /lib/modules/5.9.0-rc5buildid+/kernel/drivers/firmware/qemu_fw_cfg.ko 0 0 ... @ 0 ]: ---p /lib/modules/5.9.0-rc5buildid+/kernel/drivers/char/virtio_console.ko 0 0 ... @ 0 <86441a4c5b2c2ff5b440682f4c612bd4b426eb5c>]: ---p /lib/modules/5.9.0-rc5buildid+/kernel/lib/libcrc32c.ko Adding build id data into <> brackets. Committer testing: $ perf record -vv --buildid-mmap sleep 1 |& grep -m1 build Enabling build id in mmap2 events. $ perf evlist -v cycles:u: size: 120, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|PERIOD, read_format: ID, disabled: 1, inherit: 1, exclude_kernel: 1, mmap: 1, comm: 1, freq: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, bpf_event: 1, build_id: 1 $ $ perf script --show-mmap-events | head -4 sleep 274800 2843.556112: PERF_RECORD_MMAP2 274800/274800: [0x564e2fd32000(0x3000) @ 0x2000 ]: r-xp /usr/bin/sleep sleep 274800 2843.556129: PERF_RECORD_MMAP2 274800/274800: [0x7fa9550d7000(0x21000) @ 0x1000 ]: r-xp /usr/lib64/ld-2.32.so sleep 274800 2843.556140: PERF_RECORD_MMAP2 274800/274800: [0x7ffd8fa96000(0x2000) @ 0 00:00 0 0]: r-xp [vdso] sleep 274800 2843.556162: 1 cycles:u: ffffffffbb26bff4 [unknown] ([unknown]) $ $ perf buildid-list -i /usr/bin/sleep c37cb90b77c79fc719798b066d78ef121285843e $ perf buildid-list -i /usr/lib64/ld-2.32.so fc190f17c4f4dc4a8a26df18eaeed41ecdb2c61b And now on a system wide session to check the build ids synthesized for the kernel and some kernel modules: # perf record -a --buildid-mmap sleep 2s [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.717 MB perf.data ] # perf script --show-mmap-events | head -4 swapper 0 [000] 0.000000: PERF_RECORD_MMAP2 -1/0: [0xffffffffbb000000(0xe02557) @ 0xffffffffbb000000 ]: ---p [kernel.kallsyms]_text swapper 0 [000] 0.000000: PERF_RECORD_MMAP2 -1/0: [0xffffffffc01dc000(0x6000) @ 0 <36d21515c0b22eb2859b6419a6cdf87ef4cd01c8>]: ---p /lib/modules/5.11.0-rc1+/kernel/drivers/i2c/i2c-dev.ko swapper 0 [000] 0.000000: PERF_RECORD_MMAP2 -1/0: [0xffffffffc01eb000(0x24000) @ 0 ]: ---p /lib/modules/5.11.0-rc1+/kernel/fs/fuse/fuse.ko swapper 0 [000] 0.000000: PERF_RECORD_MMAP2 -1/0: [0xffffffffc0210000(0x7000) @ 0 ]: ---p /lib/modules/5.11.0-rc1+/kernel/drivers/block/zram/zram.ko # perf buildid-list -h kernel Usage: perf buildid-list [] -k, --kernel Show current kernel build id # perf buildid-list --kernel e71ac4b0b0631c27181dab25d63be18dad02feb8 # file /lib/modules/5.11.0-rc1+/kernel/drivers/i2c/i2c-dev.ko /lib/modules/5.11.0-rc1+/kernel/drivers/i2c/i2c-dev.ko: ELF 64-bit LSB relocatable, x86-64, version 1 (SYSV), BuildID[sha1]=36d21515c0b22eb2859b6419a6cdf87ef4cd01c8, with debug_info, not stripped # perf buildid-list -i /lib/modules/5.11.0-rc1+/kernel/drivers/i2c/i2c-dev.ko 36d21515c0b22eb2859b6419a6cdf87ef4cd01c8 # perf buildid-list -i /lib/modules/5.11.0-rc1+/kernel/fs/fuse/fuse.ko c4fbfea32d0518b3e7879de8deca40ea142bb782 # perf buildid-list -i /lib/modules/5.11.0-rc1+/kernel/drivers/block/zram/zram.ko dd6cfb10ae66aa7b1e7b37000a004004be8092e0 # Signed-off-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Acked-by: Ian Rogers Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexei Budankov Cc: Andi Kleen Cc: Mark Rutland Cc: Michael Petlan Cc: Peter Zijlstra Cc: Song Liu Cc: Stephane Eranian Link: http://lore.kernel.org/lkml/20201214105457.543111-12-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf script: Display negative tid in non-sample events

2020-09-17T19:06:22+00:00

The kernel can release tasks while they are still running. This can result in a task having no tid, in which case perf records a tid of -1. Improve the perf script output in that case. Example: Before: # cat ./autoreap.c #include #include #include #include struct sigaction act = { .sa_handler = SIG_IGN, }; int main() { pid_t child; int status = 0; sigaction(SIGCHLD, &act, NULL); child = fork(); if (child == 0) return 123; wait(&status); return 0; } # gcc -o autoreap autoreap.c # ./perf record -a -e dummy --switch-events ./autoreap [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.948 MB perf.data ] # ./perf script --show-task-events --show-switch-events | grep -C2 'autoreap\|4294967295\|-1' swapper 0 [004] 18462.673613: PERF_RECORD_SWITCH_CPU_WIDE OUT preempt next pid/tid: 25189/25189 perf 25189 [004] 18462.673614: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 0/0 autoreap 25189 [004] 18462.673800: PERF_RECORD_COMM exec: autoreap:25189/25189 autoreap 25189 [004] 18462.674042: PERF_RECORD_FORK(25191:25191):(25189:25189) autoreap 25189 [004] 18462.674050: PERF_RECORD_SWITCH_CPU_WIDE OUT next pid/tid: 0/0 swapper 0 [004] 18462.674051: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 25189/25189 swapper 0 [005] 18462.674083: PERF_RECORD_SWITCH_CPU_WIDE OUT preempt next pid/tid: 25191/25191 autoreap 25191 [005] 18462.674084: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 0/0 swapper 0 [003] 18462.674121: PERF_RECORD_SWITCH_CPU_WIDE OUT preempt next pid/tid: 11/11 rcu_preempt 11 [003] 18462.674121: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 0/0 rcu_preempt 11 [003] 18462.674124: PERF_RECORD_SWITCH_CPU_WIDE OUT next pid/tid: 0/0 swapper 0 [003] 18462.674124: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 11/11 autoreap 25191 [005] 18462.674138: PERF_RECORD_EXIT(25191:25191):(25189:25189) PERF_RECORD_SWITCH_CPU_WIDE OUT next pid/tid: 0/0 swapper 0 [005] 18462.674149: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 4294967295/4294967295 swapper 0 [004] 18462.674182: PERF_RECORD_SWITCH_CPU_WIDE OUT preempt next pid/tid: 25189/25189 autoreap 25189 [004] 18462.674183: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 0/0 autoreap 25189 [004] 18462.674218: PERF_RECORD_EXIT(25189:25189):(25188:25188) autoreap 25189 [004] 18462.674225: PERF_RECORD_SWITCH_CPU_WIDE OUT next pid/tid: 0/0 swapper 0 [004] 18462.674226: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 25189/25189 swapper 0 [007] 18462.674257: PERF_RECORD_SWITCH_CPU_WIDE OUT preempt next pid/tid: 25188/25188 After: # ./perf script --show-task-events --show-switch-events | grep -C2 'autoreap\|4294967295\|-1' swapper 0 [004] 18462.673613: PERF_RECORD_SWITCH_CPU_WIDE OUT preempt next pid/tid: 25189/25189 perf 25189 [004] 18462.673614: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 0/0 autoreap 25189 [004] 18462.673800: PERF_RECORD_COMM exec: autoreap:25189/25189 autoreap 25189 [004] 18462.674042: PERF_RECORD_FORK(25191:25191):(25189:25189) autoreap 25189 [004] 18462.674050: PERF_RECORD_SWITCH_CPU_WIDE OUT next pid/tid: 0/0 swapper 0 [004] 18462.674051: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 25189/25189 swapper 0 [005] 18462.674083: PERF_RECORD_SWITCH_CPU_WIDE OUT preempt next pid/tid: 25191/25191 autoreap 25191 [005] 18462.674084: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 0/0 swapper 0 [003] 18462.674121: PERF_RECORD_SWITCH_CPU_WIDE OUT preempt next pid/tid: 11/11 rcu_preempt 11 [003] 18462.674121: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 0/0 rcu_preempt 11 [003] 18462.674124: PERF_RECORD_SWITCH_CPU_WIDE OUT next pid/tid: 0/0 swapper 0 [003] 18462.674124: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 11/11 autoreap 25191 [005] 18462.674138: PERF_RECORD_EXIT(25191:25191):(25189:25189) :-1 -1 [005] 18462.674149: PERF_RECORD_SWITCH_CPU_WIDE OUT next pid/tid: 0/0 swapper 0 [005] 18462.674149: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: -1/-1 swapper 0 [004] 18462.674182: PERF_RECORD_SWITCH_CPU_WIDE OUT preempt next pid/tid: 25189/25189 autoreap 25189 [004] 18462.674183: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 0/0 autoreap 25189 [004] 18462.674218: PERF_RECORD_EXIT(25189:25189):(25188:25188) autoreap 25189 [004] 18462.674225: PERF_RECORD_SWITCH_CPU_WIDE OUT next pid/tid: 0/0 swapper 0 [004] 18462.674226: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 25189/25189 swapper 0 [007] 18462.674257: PERF_RECORD_SWITCH_CPU_WIDE OUT preempt next pid/tid: 25188/25188 Signed-off-by: Adrian Hunter Tested-by: Arnaldo Carvalho de Melo Cc: Andi Kleen Cc: Jiri Olsa Cc: Yu-cheng Yu Link: http://lore.kernel.org/lkml/20200909084923.9096-2-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf script: Show text poke address symbol

2020-07-10T11:39:14+00:00

It is generally more useful to show the symbol with an address. In this case, the print function requires the 'machine' which means changing callers to provide it as a parameter. It is optional because most events do not need it and the callers that matter can provide it. Committer notes: Made 'union perf_event' continue to be the first parameter to the perf_event__fprintf() and perf_event__fprintf_text_poke() events. Signed-off-by: Adrian Hunter Cc: Alexander Shishkin Cc: Borislav Petkov Cc: H. Peter Anvin Cc: Jiri Olsa Cc: Leo Yan Cc: Mark Rutland Cc: Masami Hiramatsu Cc: Mathieu Poirier Cc: Peter Zijlstra Cc: Steven Rostedt (VMware) Cc: x86@kernel.org Link: http://lore.kernel.org/lkml/20200512121922.8997-16-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add support for PERF_RECORD_TEXT_POKE

2020-07-10T11:20:01+00:00

Add processing for PERF_RECORD_TEXT_POKE events. When a text poke event is processed, then the kernel dso data cache is updated with the poked bytes. Signed-off-by: Adrian Hunter Cc: Alexander Shishkin Cc: Borislav Petkov Cc: H. Peter Anvin Cc: Jiri Olsa Cc: Leo Yan Cc: Mark Rutland Cc: Masami Hiramatsu Cc: Mathieu Poirier Cc: Peter Zijlstra Cc: Steven Rostedt (VMware) Cc: x86@kernel.org Link: http://lore.kernel.org/lkml/20200512121922.8997-12-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf script: Avoid NULL dereference on symbol

2020-04-22T13:59:02+00:00

al->sym may be NULL given current if conditions and may cause a segv. Fixes: d2bedb7863e9 ("perf script: Allow --symbol to accept hexadecimal addresses") Signed-off-by: Ian Rogers Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lore.kernel.org/lkml/20200421004329.43109-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf script: Allow --symbol to accept hexadecimal addresses

2020-04-03T12:37:56+00:00

This patch extends the perf script --symbols option to filter on hexadecimal addresses in addition to symbol names. This makes it easier to handle cases where symbols are aliased. With this patch, it is possible to mix and match symbols and hexadecimal addresses using the --symbols option. $ perf script --symbols=noploop,0x4007a0 Signed-off-by: Stephane Eranian Reviewed-by: Ian Rogers Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20200325220802.15039-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Basic support for CGROUP event

2020-04-03T12:37:55+00:00

Implement basic functionality to support cgroup tracking. Each cgroup can be identified by inode number which can be read from userspace too. The actual cgroup processing will come in the later patch. Reported-by: kernel test robot Signed-off-by: Namhyung Kim Cc: Adrian Hunter [ fix perf test failure on sampling parsing ] Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Mark Rutland Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20200325124536.2800725-4-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo