A new 'perf bench epoll' will use this, and to disable it for older
systems, add a feature test for this API.

This is just a simple program that if successfully compiled, means that
the feature is present, at least at the library level, in a build that
sets the output directory to /tmp/build/perf (using O=/tmp/build/perf),
we end up with:

  $ ls -la /tmp/build/perf/feature/test-eventfd*
  -rwxrwxr-x. 1 acme acme 8176 Nov 21 15:58 /tmp/build/perf/feature/test-eventfd.bin
  -rw-rw-r--. 1 acme acme  588 Nov 21 15:58 /tmp/build/perf/feature/test-eventfd.d
  -rw-rw-r--. 1 acme acme    0 Nov 21 15:58 /tmp/build/perf/feature/test-eventfd.make.output
  $ ldd /tmp/build/perf/feature/test-eventfd.bin
	  linux-vdso.so.1 (0x00007fff3bf3f000)
	  libc.so.6 => /lib64/libc.so.6 (0x00007fa984061000)
	  /lib64/ld-linux-x86-64.so.2 (0x00007fa984417000)
  $ grep eventfd -A 2 -B 2 /tmp/build/perf/FEATURE-DUMP
  feature-dwarf=1
  feature-dwarf_getlocations=1
  feature-eventfd=1
  feature-fortify-source=1
  feature-sync-compare-and-swap=1
  $

The main thing here is that in the end we'll have -DHAVE_EVENTFD in
CFLAGS, and then the 'perf bench' entry needing that API can be
selectively pruned.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-wkeldwob7dpx6jvtuzl8164k@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Both futex and epoll need this call, and can cause build failure on
systems that don't have it pthread_attr_setaffinity_np().
Signed-off-by: NDavidlohr Bueso <dbueso@suse.de>
Reported-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Jason Baron <jbaron@akamai.com>
Link: http://lkml.kernel.org/r/20181109210719.pr7ohayuwqmfp2wl@linux-r8p5Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The iregs output was missing the newline at end as well as the leading
ABI output. This made it hard to compare the iregs and uregs values.
Instead, use a single function to output the register values and use it
for both, iregs and uregs, to ensure the output is consistent.

Before:

  perf  7049 [-01]  1343.354347:          1 cycles:ppp:
        ffffffffa7bc21ce perf_event_exec+0x18e (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7ead3 setup_new_exec+0xf3 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7cd7be5 load_elf_binary+0x395 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7e540 search_binary_handler+0x80 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7f1aa __do_execve_file.isra.13+0x58a (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7f561 do_execve+0x21 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7f596 __x64_sys_execve+0x26 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7a041cb do_syscall_64+0x5b (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa840008c entry_SYSCALL_64+0x7c (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
    AX:0x80000000    BX:0x0    CX:0x0    DX:0x7    SI:0xf    DI:0x286    BP:0xffff95bc8213a460    SP:0xffffacbf0ba97d18    IP:0xffffffffa7bc21cd FLAGS:0x28e    CS:0x10    SS:0x18    R8:0x2    R9:0x21440   R10:0x33816fb3b8c   R11:0x1   R12:0xffff95bc8213a460   R13:0xffff95bc8213a400   R14:0xffff95bc8213a400   R15:0x1  ABI:2    AX:0xffffffffffffffda    BX:0xffffffffffffffff    CX:0x7f84ad85798b    DX:0x560209699d50    SI:0x7ffe2c7a6820    DI:0x7ffe2c7a8c9b    BP:0x7ffe2c7a20d0    SP:0x7ffe2c7a2058    IP:0x7f84ad85798b FLAGS:0x206    CS:0x33    SS:0x2b    R8:0x7ffe2c7a2030    R9:0x7f84ae55f010   R10:0x8   R11:0x206   R12:0xffffffffffffffff   R13:0xffffffffffffffff   R14:0xffffffffffffffff   R15:0xffffffffffffffff

  perf  7049 [-01]  1343.354363:          1 cycles:ppp:
        ...

After:

  perf  7049 [-01]  1343.354347:          1 cycles:ppp:
        ffffffffa7bc21ce perf_event_exec+0x18e (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7ead3 setup_new_exec+0xf3 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7cd7be5 load_elf_binary+0x395 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7e540 search_binary_handler+0x80 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7f1aa __do_execve_file.isra.13+0x58a (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7f561 do_execve+0x21 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7c7f596 __x64_sys_execve+0x26 (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa7a041cb do_syscall_64+0x5b (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
        ffffffffa840008c entry_SYSCALL_64+0x7c (/lib/modules/4.20.0-rc1perf-devel-05115-gc0bc98f76e39-dirty/build/vmlinux)
    ABI:2    AX:0x80000000    BX:0x0    CX:0x0    DX:0x7    SI:0xf    DI:0x286    BP:0xffff95bc8213a460    SP:0xffffacbf0ba97d18    IP:0xffffffffa7bc21cd FLAGS:0x28e    CS:0x10    SS:0x18    R8:0x2    R9:0x21440   R10:0x33816fb3b8c   R11:0x1   R12:0xffff95bc8213a460   R13:0xffff95bc8213a400   R14:0xffff95bc8213a400   R15:0x1
    ABI:2    AX:0xffffffffffffffda    BX:0xffffffffffffffff    CX:0x7f84ad85798b    DX:0x560209699d50    SI:0x7ffe2c7a6820    DI:0x7ffe2c7a8c9b    BP:0x7ffe2c7a20d0    SP:0x7ffe2c7a2058    IP:0x7f84ad85798b FLAGS:0x206    CS:0x33    SS:0x2b    R8:0x7ffe2c7a2030    R9:0x7f84ae55f010   R10:0x8   R11:0x206   R12:0xffffffffffffffff   R13:0xffffffffffffffff   R14:0xffffffffffffffff   R15:0xffffffffffffffff

  perf  7049 [-01]  1343.354363:          1 cycles:ppp:
        ...
Signed-off-by: NMilian Wolff <milian.wolff@kdab.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20181107223437.9071-1-milian.wolff@kdab.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

While working on augmented syscalls I got into this error:

  # trace -vv --filter-pids 2469,1663 -e tools/perf/examples/bpf/augmented_raw_syscalls.c sleep 1
  <SNIP>
  libbpf: map 0 is "__augmented_syscalls__"
  libbpf: map 1 is "__bpf_stdout__"
  libbpf: map 2 is "pids_filtered"
  libbpf: map 3 is "syscalls"
  libbpf: collecting relocating info for: '.text'
  libbpf: relo for 13 value 84 name 133
  libbpf: relocation: insn_idx=3
  libbpf: relocation: find map 3 (pids_filtered) for insn 3
  libbpf: collecting relocating info for: 'raw_syscalls:sys_enter'
  libbpf: relo for 8 value 0 name 0
  libbpf: relocation: insn_idx=1
  libbpf: relo for 8 value 0 name 0
  libbpf: relocation: insn_idx=3
  libbpf: relo for 9 value 28 name 178
  libbpf: relocation: insn_idx=36
  libbpf: relocation: find map 1 (__augmented_syscalls__) for insn 36
  libbpf: collecting relocating info for: 'raw_syscalls:sys_exit'
  libbpf: relo for 8 value 0 name 0
  libbpf: relocation: insn_idx=0
  libbpf: relo for 8 value 0 name 0
  libbpf: relocation: insn_idx=2
  bpf: config program 'raw_syscalls:sys_enter'
  bpf: config program 'raw_syscalls:sys_exit'
  libbpf: create map __bpf_stdout__: fd=3
  libbpf: create map __augmented_syscalls__: fd=4
  libbpf: create map syscalls: fd=5
  libbpf: create map pids_filtered: fd=6
  libbpf: added 13 insn from .text to prog raw_syscalls:sys_enter
  libbpf: added 13 insn from .text to prog raw_syscalls:sys_exit
  libbpf: load bpf program failed: Operation not permitted
  libbpf: failed to load program 'raw_syscalls:sys_exit'
  libbpf: failed to load object 'tools/perf/examples/bpf/augmented_raw_syscalls.c'
  bpf: load objects failed: err=-4009: (Incorrect kernel version)
  event syntax error: 'tools/perf/examples/bpf/augmented_raw_syscalls.c'
                       \___ Failed to load program for unknown reason

  (add -v to see detail)
  Run 'perf list' for a list of valid events

   Usage: perf trace [<options>] [<command>]
      or: perf trace [<options>] -- <command> [<options>]
      or: perf trace record [<options>] [<command>]
      or: perf trace record [<options>] -- <command> [<options>]

      -e, --event <event>   event/syscall selector. use 'perf list' to list available events

If I then try to use strace (perf trace'ing 'perf trace' needs some more work
before its possible) to get a bit more info I get:

  # strace -e bpf trace --filter-pids 2469,1663 -e tools/perf/examples/bpf/augmented_raw_syscalls.c sleep 1
  bpf(BPF_MAP_CREATE, {map_type=BPF_MAP_TYPE_PERF_EVENT_ARRAY, key_size=4, value_size=4, max_entries=4, map_flags=0, inner_map_fd=0, map_name="__bpf_stdout__", map_ifindex=0}, 72) = 3
  bpf(BPF_MAP_CREATE, {map_type=BPF_MAP_TYPE_PERF_EVENT_ARRAY, key_size=4, value_size=4, max_entries=4, map_flags=0, inner_map_fd=0, map_name="__augmented_sys", map_ifindex=0}, 72) = 4
  bpf(BPF_MAP_CREATE, {map_type=BPF_MAP_TYPE_ARRAY, key_size=4, value_size=1, max_entries=500, map_flags=0, inner_map_fd=0, map_name="syscalls", map_ifindex=0}, 72) = 5
  bpf(BPF_MAP_CREATE, {map_type=BPF_MAP_TYPE_HASH, key_size=4, value_size=1, max_entries=512, map_flags=0, inner_map_fd=0, map_name="pids_filtered", map_ifindex=0}, 72) = 6
  bpf(BPF_PROG_LOAD, {prog_type=BPF_PROG_TYPE_TRACEPOINT, insn_cnt=57, insns=0x1223f50, license="GPL", log_level=0, log_size=0, log_buf=NULL, kern_version=KERNEL_VERSION(4, 18, 10), prog_flags=0, prog_name="sys_enter", prog_ifindex=0, expected_attach_type=BPF_CGROUP_INET_INGRESS}, 72) = 7
  bpf(BPF_PROG_LOAD, {prog_type=BPF_PROG_TYPE_TRACEPOINT, insn_cnt=18, insns=0x1224120, license="GPL", log_level=0, log_size=0, log_buf=NULL, kern_version=KERNEL_VERSION(4, 18, 10), prog_flags=0, prog_name="sys_exit", prog_ifindex=0, expected_attach_type=BPF_CGROUP_INET_INGRESS}, 72) = -1 EPERM (Operation not permitted)
  bpf(BPF_PROG_LOAD, {prog_type=BPF_PROG_TYPE_TRACEPOINT, insn_cnt=18, insns=0x1224120, license="GPL", log_level=1, log_size=262144, log_buf="", kern_version=KERNEL_VERSION(4, 18, 10), prog_flags=0, prog_name="sys_exit", prog_ifindex=0, expected_attach_type=BPF_CGROUP_INET_INGRESS}, 72) = -1 EPERM (Operation not permitted)
  bpf(BPF_PROG_LOAD, {prog_type=BPF_PROG_TYPE_KPROBE, insn_cnt=18, insns=0x1224120, license="GPL", log_level=0, log_size=0, log_buf=NULL, kern_version=KERNEL_VERSION(4, 18, 10), prog_flags=0, prog_name="sys_exit", prog_ifindex=0, expected_attach_type=BPF_CGROUP_INET_INGRESS}, 72) = -1 EPERM (Operation not permitted)
  event syntax error: 'tools/perf/examples/bpf/augmented_raw_syscalls.c'
                       \___ Failed to load program for unknown reason
  <SNIP similar output as without 'strace'>
  #

I managed to create the maps, etc, but then installing the "sys_exit" hook into
the "raw_syscalls:sys_exit" tracepoint somehow gets -EPERMed...

I then go and try reducing the size of this new table:

  +++ b/tools/perf/examples/bpf/augmented_raw_syscalls.c
  @@ -47,6 +47,17 @@ struct augmented_filename {
   #define SYS_OPEN 2
   #define SYS_OPENAT 257

  +struct syscall {
  +       bool    filtered;
  +};
  +
  +struct bpf_map SEC("maps") syscalls = {
  +       .type        = BPF_MAP_TYPE_ARRAY,
  +       .key_size    = sizeof(int),
  +       .value_size  = sizeof(struct syscall),
  +       .max_entries = 500,
  +};

And after reducing that .max_entries a tad, it works. So yeah, the "unknown
reason" should be related to the number of bytes all this is taking, reduce the
default for pid_map()s so that we can have a "syscalls" map with enough slots
for all syscalls in most arches. And take notes about this error message,
improve it :-)

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: Edward Cree <ecree@solarflare.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lkml.kernel.org/n/tip-yjzhak8asumz9e9hts2dgplp@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This change makes it much easier to easily distinguish between
consecutive samples by keeping the empty line between them, like we see
when we do not enable uregs output.

Before:

  cpp-inlining 28298 [-01] 54837.342780:    3068085 cycles:pp:
              7ffff7c96709 __hypot_finite+0xa9 (/usr/lib/libm-2.28.so)
              ...
   ABI:2    AX:0x0    BX:0x40f56cf6    CX:0x294a3ae7    ...
  cpp-inlining 28298 [-01] 54837.344493:    2881929 cycles:pp:
              7ffff7c96696 __hypot_finite+0x36 (/usr/lib/libm-2.28.so)
              ...
   ABI:2    AX:0x40d440c7    BX:0x40d440c7    CX:0x4d45e5da    ...

After:

  cpp-inlining 28298 [-01] 54837.342780:    3068085 cycles:pp:
              7ffff7c96709 __hypot_finite+0xa9 (/usr/lib/libm-2.28.so)
              ...
   ABI:2    AX:0x0    BX:0x40f56cf6    CX:0x294a3ae7    ...

  cpp-inlining 28298 [-01] 54837.344493:    2881929 cycles:pp:
              7ffff7c96696 __hypot_finite+0x36 (/usr/lib/libm-2.28.so)
              ...
   ABI:2    AX:0x40d440c7    BX:0x40d440c7    CX:0x4d45e5da    ...
Signed-off-by: NMilian Wolff <milian.wolff@kdab.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20181107093705.16346-1-milian.wolff@kdab.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Now that we have the "filtered_pids" logic in place, no need to do this
rough filter to avoid the feedback loop from 'perf trace's own syscalls,
revert it.

This reverts commit 7ed71f124284359676b6496ae7db724fee9da753.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-88vh02cnkam0vv5f9vp02o3h@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Now that 'perf trace' fills in that "filtered_pids" BPF map, remove the
set of filtered pids used as an example to test that feature.

That feature works like this:

Starting a system wide 'strace' like 'perf trace' augmented session we
noticed that lots of events take place for a pid, which ends up being
the feedback loop of perf trace's syscalls being processed by the
'gnome-terminal' process:

  # perf trace -e tools/perf/examples/bpf/augmented_raw_syscalls.c
     0.391 ( 0.002 ms): gnome-terminal/2469 read(fd: 17</dev/ptmx>, buf: 0x564b79f750bc, count: 8176) = 453
     0.394 ( 0.001 ms): gnome-terminal/2469 read(fd: 17</dev/ptmx>, buf: 0x564b79f75280, count: 7724) = -1 EAGAIN Resource temporarily unavailable
     0.438 ( 0.001 ms): gnome-terminal/2469 read(fd: 4<anon_inode:[eventfd]>, buf: 0x7fffc696aeb0, count: 16) = 8
     0.519 ( 0.001 ms): gnome-terminal/2469 read(fd: 17</dev/ptmx>, buf: 0x564b79f75280, count: 7724) = 114
     0.522 ( 0.001 ms): gnome-terminal/2469 read(fd: 17</dev/ptmx>, buf: 0x564b79f752f1, count: 7611) = -1 EAGAIN Resource temporarily unavailable
  ^C

So we can use --filter-pids to get rid of that one, and in this case what is
being used to implement that functionality is that "filtered_pids" BPF map that
the tools/perf/examples/bpf/augmented_raw_syscalls.c created and that 'perf trace'
bpf loader noticed and created a "struct bpf_map" associated that then got populated
by 'perf trace':

  # perf trace --filter-pids 2469 -e tools/perf/examples/bpf/augmented_raw_syscalls.c
     0.020 ( 0.002 ms): gnome-shell/1663 epoll_pwait(epfd: 12<anon_inode:[eventpoll]>, events: 0x7ffd8f3ef960, maxevents: 32, sigsetsize: 8) = 1
     0.025 ( 0.002 ms): gnome-shell/1663 read(fd: 24</dev/input/event4>, buf: 0x560c01bb8240, count: 8112) = 48
     0.029 ( 0.001 ms): gnome-shell/1663 read(fd: 24</dev/input/event4>, buf: 0x560c01bb8258, count: 8088) = -1 EAGAIN Resource temporarily unavailable
     0.032 ( 0.001 ms): gnome-shell/1663 read(fd: 24</dev/input/event4>, buf: 0x560c01bb8240, count: 8112) = -1 EAGAIN Resource temporarily unavailable
     0.040 ( 0.003 ms): gnome-shell/1663 recvmsg(fd: 46<socket:[35893]>, msg: 0x7ffd8f3ef950) = -1 EAGAIN Resource temporarily unavailable
    21.529 ( 0.002 ms): gnome-shell/1663 epoll_pwait(epfd: 5<anon_inode:[eventpoll]>, events: 0x7ffd8f3ef960, maxevents: 32, sigsetsize: 8) = 1
    21.533 ( 0.004 ms): gnome-shell/1663 recvmsg(fd: 82<socket:[42826]>, msg: 0x7ffd8f3ef7b0, flags: DONTWAIT|CMSG_CLOEXEC) = 236
    21.581 ( 0.006 ms): gnome-shell/1663 ioctl(fd: 8</dev/dri/card0>, cmd: DRM_I915_GEM_BUSY, arg: 0x7ffd8f3ef060) = 0
    21.605 ( 0.020 ms): gnome-shell/1663 ioctl(fd: 8</dev/dri/card0>, cmd: DRM_I915_GEM_CREATE, arg: 0x7ffd8f3eeea0) = 0
    21.626 ( 0.119 ms): gnome-shell/1663 ioctl(fd: 8</dev/dri/card0>, cmd: DRM_I915_GEM_SET_DOMAIN, arg: 0x7ffd8f3eee94) = 0
    21.746 ( 0.081 ms): gnome-shell/1663 ioctl(fd: 8</dev/dri/card0>, cmd: DRM_I915_GEM_PWRITE, arg: 0x7ffd8f3eeea0) = 0
  ^C

Oops, yet another gnome process that is involved with the output that
'perf trace' generates, lets filter that out too:

  # perf trace --filter-pids 2469,1663 -e tools/perf/examples/bpf/augmented_raw_syscalls.c
         ? (         ): wpa_supplicant/1366  ... [continued]: select()) = 0 Timeout
     0.006 ( 0.002 ms): wpa_supplicant/1366 clock_gettime(which_clock: BOOTTIME, tp: 0x7fffe5b1e430) = 0
     0.011 ( 0.001 ms): wpa_supplicant/1366 clock_gettime(which_clock: BOOTTIME, tp: 0x7fffe5b1e3e0) = 0
     0.014 ( 0.001 ms): wpa_supplicant/1366 clock_gettime(which_clock: BOOTTIME, tp: 0x7fffe5b1e430) = 0
         ? (         ): gmain/1791  ... [continued]: poll()) = 0 Timeout
     0.017 (         ): wpa_supplicant/1366 select(n: 6, inp: 0x55646fed3ad0, outp: 0x55646fed3b60, exp: 0x55646fed3bf0, tvp: 0x7fffe5b1e4a0) ...
   157.879 ( 0.019 ms): gmain/1791 inotify_add_watch(fd: 8<anon_inode:inotify>, pathname: , mask: 16789454) = -1 ENOENT No such file or directory
         ? (         ): cupsd/1001  ... [continued]: epoll_pwait()) = 0
         ? (         ): gsd-color/1908  ... [continued]: poll()) = 0 Timeout
   499.615 (         ): cupsd/1001 epoll_pwait(epfd: 4<anon_inode:[eventpoll]>, events: 0x557a21166500, maxevents: 4096, timeout: 1000, sigsetsize: 8) ...
   586.593 ( 0.004 ms): gsd-color/1908 recvmsg(fd: 3<socket:[38074]>, msg: 0x7ffdef34e800) = -1 EAGAIN Resource temporarily unavailable
         ? (         ): fwupd/2230  ... [continued]: poll()) = 0 Timeout
         ? (         ): rtkit-daemon/906  ... [continued]: poll()) = 0 Timeout
         ? (         ): rtkit-daemon/907  ... [continued]: poll()) = 1
   724.603 ( 0.007 ms): rtkit-daemon/907 read(fd: 6<anon_inode:[eventfd]>, buf: 0x7f05ff768d08, count: 8) = 8
         ? (         ): ssh/5461  ... [continued]: select()) = 1
   810.431 ( 0.002 ms): ssh/5461 clock_gettime(which_clock: BOOTTIME, tp: 0x7ffd7f39f870) = 0
   ^C

Several syscall exit events for syscalls in flight when 'perf trace' started, etc. Saner :-)

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-c3tu5yg204p5mvr9kvwew07n@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This makes the augmented_syscalls support the --filter-pids and
auto-filtered feedback loop pids just like when working without BPF,
i.e. with just raw_syscalls:sys_{enter,exit} and tracepoint filters.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-zc5n453sxxm0tz1zfwwelyti@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Lookup for the first map named "filtered_pids" and, if augmenting
syscalls, i.e. if a BPF event is present and the
"__augmented_syscalls__" is present, then fill in that map with the pids
to filter, be it feedback loop ones (perf trace's pid, its father if it
is "sshd", more auto-filtered in the future) or the ones explicitely
stated in the tool command line via --filter-pids.

The code to actually fill in the map comes next.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-rhzytmw7qpe6lqyjxi1ded9t@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

As we'll need that name for a new function to set filters for both
tracepoints and BPF maps for filtering pids.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-mdkck6hf3fnd21rz2766280q@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To better reflect that this is a tracepoint filter, as opposed, for
instance to map based BPF filters.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-9138svli6ddcphrr3ymy9oy3@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Just to test filtering a bunch of pids, now its time to go and get that
hooked up in 'perf trace', right after we load the bpf program, if we
find a "pids_filtered" map defined, we'll populate it with the filtered
pids.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-1i9s27wqqdhafk3fappow84x@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When testing system wide tracing without filtering the syscalls called
by 'perf trace' itself we get into a feedback loop, drop for now those
two syscalls, that are the ones that 'perf trace' does in its loop for
writing the syscalls it intercepts, to help with testing till we get
that filtering in place.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-rkbu536af66dbsfx51sr8yof@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Will be used in the augmented_raw_syscalls.c to implement 'perf trace
--filter-pids'.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-9sybmz4vchlbpqwx2am13h9e@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Starting with a helper for a basic pid_map(), a hash using a pid as a
key.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-gdwvq53wltvq6b3g5tdmh0cw@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Leftover from when we started augmented_raw_syscalls.c from
tools/perf/examples/bpf/augmented_syscalls.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: e58a0322dbac ("perf examples bpf: Start augmenting raw_syscalls:sys_{start,exit}")
Link: https://lkml.kernel.org/n/tip-pmts9ls2skh8n3zisb4txudd@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Just to show where we'll hook pid based filters, and what we use to
obtain the current pid, using a BPF getpid() equivalent.

Now we need to remove that hardcoded PID with a BPF hash map, so that we
start by filtering 'perf trace's own PID, implement the --filter-pid
functionality, etc.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-oshrcgcekiyhd0whwisxfvtv@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Start with a getpid() function wrapping BPF_FUNC_get_current_pid_tgid,
idea is to mimic the system headers.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-zo8hv22onidep7tm785dzxfk@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Introduced in:

  ad8c0eaa ("tty/serial_core: add ISO7816 infrastructure")

Now 'perf trace' will be able to pretty-print the 'cmd' ioctl arg when
used in capable systems with software emitting those commands.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-7bds48dhckfnleie08mit314@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To pick up the changes in:

  ad8c0eaa ("tty/serial_core: add ISO7816 infrastructure")

That is a change that imply a change to be made in tools/perf/trace/beauty/ioctl.c to
make 'perf trace' ioctl syscall argument beautifier to support these new
commands:  TIOCGISO7816 and TIOCSISO7816.

This is not yet done automatically by a script like is done for some
other headers, for instance:

  $ tools/perf/trace/beauty/drm_ioctl.sh | head
  #ifndef DRM_COMMAND_BASE
  #define DRM_COMMAND_BASE                0x40
  #endif
  static const char *drm_ioctl_cmds[] = {
	[0x00] = "VERSION",
	[0x01] = "GET_UNIQUE",
	[0x02] = "GET_MAGIC",
	[0x03] = "IRQ_BUSID",
	[0x04] = "GET_MAP",
	[0x05] = "GET_CLIENT",
  $

So we will need to change tools/perf/trace/beauty/ioctl.c in a follow up
patch until we switch to a generator script.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-zin76fe6iykqsilvo6u47f9o@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To get the changes in the following csets:

  ace6485a ("x86/cpufeatures: Enumerate MOVDIR64B instruction")
  33823f4d ("x86/cpufeatures: Enumerate MOVDIRI instruction")

No tools were affected, copy it to silence this perf tool build warning:

  Warning: Kernel ABI header at 'tools/arch/x86/include/asm/cpufeatures.h' differs from latest version at 'arch/x86/include/asm/cpufeatures.h'
  diff -u tools/arch/x86/include/asm/cpufeatures.h arch/x86/include/asm/cpufeatures.h

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Link: https://lkml.kernel.org/n/tip-83kcyqa1qkxkhm1s7q3hbpel@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To pick up the changes in:

  900ccf30 ("drm/i915: Only force GGTT coherency w/a on required chipsets")

No changes are required in tools/ nor does anything gets automatically
generated to be used in the 'perf trace' syscall arg beautifiers.

This silences this perf build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/drm/i915_drm.h' differs from latest version at 'include/uapi/drm/i915_drm.h'
  diff -u tools/include/uapi/drm/i915_drm.h include/uapi/drm/i915_drm.h

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-t2vor2wegv41gt5n49095kly@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When reporting on 'record' server we try to retrieve/use the mnt
namespace of the profiled tasks. We use following API with cookie to
hold the return namespace, roughly:

  nsinfo__mountns_enter(struct nsinfo *nsi, struct nscookie *nc)
    setns(newns, 0);
  ...
  new ns related open..
  ...
  nsinfo__mountns_exit(struct nscookie *nc)
    setns(nc->oldns)

Once finished we setns to old namespace, which also sets the current
working directory (cwd) to "/", trashing the cwd we had.

This is mostly fine, because we use absolute paths almost everywhere,
but it screws up 'perf diff':

  # perf diff
  failed to open perf.data: No such file or directory  (try 'perf record' first)
  ...

Adding the current working directory to be part of the cookie and
restoring it in the nsinfo__mountns_exit call.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: 843ff37b ("perf symbols: Find symbols in different mount namespace")
Link: http://lkml.kernel.org/r/20181101170001.30019-1-jolsa@kernel.org
[ No need to check for NULL args for free(), use zfree() for struct members ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

As the namespace support code will use this, which is not available in
some non _GNU_SOURCE libraries such as Android's bionic used in my
container build tests (r12b and r15c at the moment).

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-x56ypm940pwclwu45d7jfj47@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Currently the selftest wild_bctr can fail to build when an old gcc is
used, notably on gcc using a binutils version <= 2.27, because the
assembler does not support the integer suffix UL.

This patch adjusts the wild_bctr test so the REG_POISON value is still
treated as an unsigned long for the shifts on compilation but the UL
suffix is absent on the stringification, so the inline asm code
generated has no UL suffixes.
Signed-off-by: NGustavo Romero <gromero@linux.vnet.ibm.com>
[mpe: Wrap long line]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Adam reported a record command crash for simple session like:

  $ perf record -e cpu-clock ls

with following backtrace:

  Program received signal SIGSEGV, Segmentation fault.
  3543            ev = event_update_event__new(size + 1, PERF_EVENT_UPDATE__UNIT, evsel->id[0]);
  (gdb) bt
  #0  perf_event__synthesize_event_update_unit
  #1  0x000000000051e469 in perf_event__synthesize_extra_attr
  #2  0x00000000004445cb in record__synthesize
  #3  0x0000000000444bc5 in __cmd_record
  ...

We synthesize an update event that needs to touch the evsel id array,
which is not defined at that time. Fix this by forcing the id allocation
for events with their unit defined.

Reflecting possible read_format ID bit in the attr tests.
Reported-by: NYongxin Liu <yongxin.liu@outlook.com>
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Cc: Adam Lee <leeadamrobert@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=201477
Fixes: bfd8f72c ("perf record: Synthesize unit/scale/... in event update")
Link: http://lkml.kernel.org/r/20181112130012.5424-1-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The selftest I recently added to test branching to an out-of-bounds
NIP doesn't work on 64-bit big endian. It does fail but not in the
right way. That is it SEGVs trying to load from the opd at BAD_NIP,
but it never gets as far as branching to BAD_NIP.

To fix it we need to create an opd which is reachable but which holds
the bad address.

Fixes: b7683fc6 ("selftests/powerpc: Add a test of wild bctr")
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Andi reported following malfunction:

  # perf record -e '{ref-cycles,cycles}:S' -a sleep 1
  # perf script
  non matching sample_id_all

That's because we disable sample_id_all bit for non-sampling group
members. We can't do that, because it needs to be the same over the
whole event list. This patch keeps it untouched again.
Reported-by: NAndi Kleen <andi@firstfloor.org>
Tested-by: NAndi Kleen <andi@firstfloor.org>
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180923150420.27327-1-jolsa@kernel.org
Fixes: e9add8ba ("perf evsel: Disable write_backward for leader sampling group events")
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

KASAN reports following global out of bounds access while
nfit_test is being loaded. The out of bound access happens
the following reference to dimm_fail_cmd_flags[dimm]. 'dimm' is
over than the index value, NUM_DCR (==5).

  static int override_return_code(int dimm, unsigned int func, int rc)
  {
          if ((1 << func) & dimm_fail_cmd_flags[dimm]) {

dimm_fail_cmd_flags[] definition:
  static unsigned long dimm_fail_cmd_flags[NUM_DCR];

'dimm' is the return value of get_dimm(), and get_dimm() returns
the index of handle[] array. The handle[] has 7 index. Let's use
ARRAY_SIZE(handle) as the array size.

KASAN report:

==================================================================
BUG: KASAN: global-out-of-bounds in nfit_test_ctl+0x47bb/0x55b0 [nfit_test]
Read of size 8 at addr ffffffffc10cbbe8 by task kworker/u41:0/8
...
Call Trace:
 dump_stack+0xea/0x1b0
 ? dump_stack_print_info.cold.0+0x1b/0x1b
 ? kmsg_dump_rewind_nolock+0xd9/0xd9
 print_address_description+0x65/0x22e
 ? nfit_test_ctl+0x47bb/0x55b0 [nfit_test]
 kasan_report.cold.6+0x92/0x1a6
 nfit_test_ctl+0x47bb/0x55b0 [nfit_test]
...
The buggy address belongs to the variable:
 dimm_fail_cmd_flags+0x28/0xffffffffffffa440 [nfit_test]
==================================================================

Fixes: 39611e83 ("tools/testing/nvdimm: Make DSM failure code injection...")
Signed-off-by: NMasayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Currently jvmti agent can not be used because function scnprintf is not
present in the agent libperf-jvmti.so. As a result the JVM when using
such agent to record JITed code profiling information will fail on
looking up scnprintf:

  java: symbol lookup error: lib/libperf-jvmti.so: undefined symbol: scnprintf

This commit fixes that by reverting to the use of snprintf, that can be
looked up, instead of scnprintf, adding a proper check for the returned
value in order to print a better error message when the jitdump file
pathname is too long. Checking the returned value also helps to comply
with some recent gcc versions, like gcc8, which will fail due to
truncated writing checks related to the -Werror=format-truncation= flag.
Signed-off-by: NGustavo Romero <gromero@linux.vnet.ibm.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
LPU-Reference: 1541117601-18937-2-git-send-email-gromero@linux.vnet.ibm.com
Link: https://lkml.kernel.org/n/tip-mvpxxxy7wnzaj74cq75muw3f@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Guenter reported that using ARCH=x86_64 to build perf has regressed:

  $ make -C tools/perf O=/tmp/build/perf ARCH=x86_64
  make: Entering directory '/home/acme/git/perf/tools/perf'
    BUILD:   Doing 'make -j4' parallel build
    HOSTCC   /tmp/build/perf/fixdep.o
    HOSTLD   /tmp/build/perf/fixdep-in.o
    LINK     /tmp/build/perf/fixdep

  Auto-detecting system features:
  ...                         dwarf: [ on  ]
  <SNIP>
  ...                           bpf: [ on  ]

    GEN      /tmp/build/perf/common-cmds.h
  make[2]: *** No rule to make target '/home/acme/git/perf/tools/arch/x86_64/include/uapi/asm//mman.h', needed by '/tmp/build/perf/trace/beauty/generated/mmap_flags_array.c'.  Stop.
  make[2]: *** Waiting for unfinished jobs....
    PERF_VERSION = 4.19.gf6c23e3b
  make[1]: *** [Makefile.perf:207: sub-make] Error 2
  make: *** [Makefile:70: all] Error 2
  make: Leaving directory '/home/acme/git/perf/tools/perf'
  $

This is because we must use $(SRCARCH) where we were using $(ARCH), so
that, just like the top level Makefile, we get this done:

  # Additional ARCH settings for x86
  ifeq ($(ARCH),i386)
          SRCARCH := x86
  endif
  ifeq ($(ARCH),x86_64)
          SRCARCH := x86
  endif

Which is done in tools/scripts/Makefile.arch, so switch to use
$(SRCARCH).
Reported-by: NGuenter Roeck <linux@roeck-us.net>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Clark Williams <williams@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: fbd7458d ("perf beauty: Wire up the mmap flags table generator to the Makefile")
Link: https://lkml.kernel.org/r/20181105184612.GD7077@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

One cause of decoding errors is un-synchronized side-band data.
Timestamps are needed to debug such cases. TSC packet timestamps are
logged. Log also MTC and CYC timestamps.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Link: http://lkml.kernel.org/r/20181105073505.8129-3-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

More event information is useful for debugging, especially MMAP events.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Link: http://lkml.kernel.org/r/20181105073505.8129-2-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Table rows can be re-ordered by selecting a column to sort by. After
re-ordering, the "find" operation was highlighting the wrong row, fix
it.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20181104151238.15947-5-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add a window to display help. It is also possible to display the help
only, by using the option "--help-only" instead of a database name.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20181104151238.15947-4-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Fetching data from the database can be slow. Add a report that provides
the ability to select a subset of branches.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20181104151238.15947-3-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Fall back to /usr/local/lib/libxed.so to cater for distributions that do
not have /usr/local/lib in the library path by default.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20181104151238.15947-2-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

'perf report' has supported the displaying of LBR stats (such as cycles,
predicted%) in callchain entry.

For example:

  $ perf report --branch-history --stdio

  --1.01%--intel_idle mwait.h:29
            intel_idle cpufeature.h:164 (cycles:5)
            intel_idle cpufeature.h:164 (predicted:76.4%)
            intel_idle mwait.h:102 (cycles:41)
            intel_idle current.h:15

While 'perf top' doesn't support that.

For example:

  $ perf top -a -b --call-graph branch

  -   13.86%     0.23%  [kernel]		[k] __x86_indirect_thunk_rax
     - 13.65% __x86_indirect_thunk_rax
        + 1.69% do_syscall_64
        + 1.68% do_select
        + 1.41% ktime_get
        + 0.70% __schedule
        + 0.62% do_sys_poll
          0.58% __x86_indirect_thunk_rax

Actually it's very easy to enable this feature in 'perf top'.

With this patch, the result is:

  $ perf top -a -b --call-graph branch

  $ -   13.58%     0.00%  [kernel]		[k] __x86_indirect_thunk_rax
     $ - 13.57% __x86_indirect_thunk_rax (predicted:93.9%)
        $ + 1.78% do_select (cycles:2)
        $ + 1.68% perf_pmu_disable.part.99 (cycles:1)
        $ + 1.45% ___sys_recvmsg (cycles:25)
        $ + 0.81% unix_stream_sendmsg (cycles:18)
        $ + 0.80% ktime_get (cycles:400)
          $ 0.58% pick_next_task_fair (cycles:47)
        $ + 0.56% i915_request_retire (cycles:2)
        $ + 0.52% do_sys_poll (cycles:4)
Signed-off-by: NJin Yao <yao.jin@linux.intel.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1540983995-20462-1-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

On s390 the CPU Measurement Facility for counters now supports
2 PMUs named cpum_cf (CPU Measurement Facility for counters) and
cpum_cf_diag (CPU Measurement Facility for diagnostic counters)
for one and the same CPU.

Running command

 [root@s35lp76 perf]# ./perf stat -e tx_c_tend \
	 -- ~/mytests/cf-tx-events 1

 Measuring transactions
 TX_C_TABORT_NO_SPECIAL: 0 expected:0
 TX_C_TABORT_SPECIAL: 0 expected:0
 TX_C_TEND: 1 expected:1
 TX_NC_TABORT: 11 expected:11
 TX_NC_TEND: 1 expected:1

 Performance counter stats for '/root/mytests/cf-tx-events 1':

  2      tx_c_tend

      0.002120091 seconds time elapsed

      0.000121000 seconds user
      0.002127000 seconds sys

 [root@s35lp76 perf]#

displays output which is unexpected (and wrong):

  2      tx_c_tend

The test program definitely triggers only one transaction, as shown
in line 'TX_C_TEND: 1 expected:1'.

This is caused by the following call sequence:

pmu_lookup() scans and installs a PMU.
+--> pmu_aliases() parses all aliases in directory
		.../<pmu-name>/events/* which are file names.
     +--> pmu_aliases_parse() Read each file in directory and create
                      an new alias entry. This is done with
          +--> perf_pmu__new_alias() and
	       +--> __perf_pmu__new_alias() which also check for
	                   identical alias names.

After pmu_aliases() returns, a complete list of event names
for this pmu has been created. Now function

pmu_add_cpu_aliases()   is called to add the events listed in the json
|                       files to the alias list of the cpu.
+--> perf_pmu__find_map()  Returns a pointer to the json events.

Now function pmu_add_cpu_aliases() scans through all events listed
in the JSON files for this CPU.
Each json event pmu name is compared with the current PMU being
built up and if they mismatch, the json event is added to the
current PMUs alias list.
To avoid duplicate entries the following comparison is done:

	if (!is_arm_pmu_core(name)) {
	     pname = pe->pmu ? pe->pmu : "cpu";
	     if (strncmp(pname, name, strlen(pname)))
		     continue;
     }

The culprit is the strncmp() function.

Using current s390 PMU naming, the first PMU is 'cpum_cf'
and a long list of events is added, among them 'tx_c_tend'

When the second PMU named 'cpum_cf_diag' is added, only one event
named 'CF_DIAG' is added by the pmu_aliases()  function.

Now function pmu_add_cpu_aliases() is invoked for PMU 'cpum_cf_diag'.
Since the CPUID string is the same for both PMUs, json file events
for PMU named 'cpum_cf' are added to the PMU 'cpm_cf_diag'

This happens because the strncmp() actually compares:

     strncmp("cpum_cf", "cpum_cf_diag", 6);

The first parameter is the pmu name taken from the event in
the json file. The second parameter is the pmu name of the PMU
currently being built.
They are different, but the length of the compare only tests the
common prefix and this returns 0(true) when it should return false.

Now all events for PMU cpum_cf are added to the alias list for pmu
cpum_cf_diag.

Later on in function parse_events_add_pmu() the event 'tx_c_end' is
searched in all available PMUs and found twice, adding it two
times to the evsel_list global variable which is the root
of all events. This results in a counter value of 2 instead
of 1.

Output with this patch:

 [root@s35lp76 perf]# ./perf stat -e tx_c_tend \
			-- ~/mytests/cf-tx-events 1
 Measuring transactions
 TX_C_TABORT_NO_SPECIAL: 0 expected:0
 TX_C_TABORT_SPECIAL: 0 expected:0
 TX_C_TEND: 1 expected:1
 TX_NC_TABORT: 11 expected:11
 TX_NC_TEND: 1 expected:1

 Performance counter stats for '/root/mytests/cf-tx-events 1':

                  1      tx_c_tend

      0.001815365 seconds time elapsed

      0.000123000 seconds user
      0.001756000 seconds sys

 [root@s35lp76 perf]#
Signed-off-by: NThomas Richter <tmricht@linux.ibm.com>
Reviewed-by: NHendrik Brueckner <brueckner@linux.ibm.com>
Reviewed-by: NSebastien Boisvert <sboisvert@gydle.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: stable@vger.kernel.org
Fixes: 292c34c1 ("perf pmu: Fix core PMU alias list for X86 platform")
Link: http://lkml.kernel.org/r/20181023151616.78193-1-tmricht@linux.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Implement a weak group fallback for 'perf record', similar to the
existing 'perf stat' support.  This allows to use groups that might be
longer than the available counters without failing.

Before:

  $ perf record  -e '{cycles,cache-misses,cache-references,cpu_clk_unhalted.thread,cycles,cycles,cycles}' -a sleep 1
  Error:
  The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (cycles).
  /bin/dmesg | grep -i perf may provide additional information.

After:

  $ ./perf record  -e '{cycles,cache-misses,cache-references,cpu_clk_unhalted.thread,cycles,cycles,cycles}:W' -a sleep 1
  WARNING: No sample_id_all support, falling back to unordered processing
  [ perf record: Woken up 3 times to write data ]
  [ perf record: Captured and wrote 8.136 MB perf.data (134069 samples) ]
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20181001195927.14211-2-andi@firstfloor.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>