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  1. 23 May, 2018 1 commit
  3. 22 May, 2018 4 commits
  5. 21 May, 2018 3 commits
  7. 19 May, 2018 5 commits
  9. 18 May, 2018 2 commits
    • Jin Yao's avatar
      perf annotate: Record the min/max cycles · 48659ebf
      Jin Yao authored 
      Currently perf has a feature to account cycles for LBRs

For example, on skylake:

  perf record -b ...
  perf report or perf annotate

And then browsing the annotate browser gives average cycle counts for
program blocks.

For some analysis it would be useful if we could know not only the
average cycles but also the min and max cycles.

This patch records the min and max cycles.
Signed-off-by: default avatarJin Yao <yao.jin@linux.intel.com>
Tested-by: default avatarArnaldo 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/1526569118-14217-2-git-send-email-yao.jin@linux.intel.com
[ Switch from max/min to min/max ]
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      48659ebf
    • Sandipan Das's avatar
      perf script: Show symbol offsets by default · 7903a708
      Sandipan Das authored 
      Since the ip shown for a symbol is now always a virtual address, it
becomes difficult to correlate this with objdump output and determine
the exact instruction address. So, we always show the offset from the
start of the symbol.

This can be verified on a powerpc64le system running Fedora 27 as
follows:

  # perf probe -a sys_write
  # perf record -e probe:sys_write -g ~/test

Before applying this patch:

  # perf script

  test  9710 [013] 95614.332431: probe:sys_write: (c0000000004025b0)
          c0000000004025b0 sys_write (/lib/modules/4.17.0-rc4+/build/vmlinux)
          c00000000000b9e0 system_call (/lib/modules/4.17.0-rc4+/build/vmlinux)
              7fffb70d8234 __GI___libc_write (/usr/lib64/libc-2.26.so)
              7fffb7052c74 _IO_file_write@@GLIBC_2.17 (/usr/lib64/libc-2.26.so)
                  5afc1818 [unknown] ([unknown])
              7fffb7051a60 new_do_write (/usr/lib64/libc-2.26.so)
              7fffb7054638 _IO_do_write@@GLIBC_2.17 (/usr/lib64/libc-2.26.so)
              7fffb7054bbc _IO_file_overflow@@GLIBC_2.17 (/usr/lib64/libc-2.26.so)
              7fffb7055a24 __overflow (/usr/lib64/libc-2.26.so)
              7fffb7044548 _IO_puts (/usr/lib64/libc-2.26.so)
                  10000440 main (/home/sandipan/test)
              7fffb6fe36a0 generic_start_main.isra.0 (/usr/lib64/libc-2.26.so)
              7fffb6fe3898 __libc_start_main (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])
  ...

After applying this patch:

  # perf script

  test  9710 [013] 95614.332431: probe:sys_write: (c0000000004025b0)
          c0000000004025b0 sys_write+0x10 (/lib/modules/4.17.0-rc4+/build/vmlinux)
          c00000000000b9e0 system_call+0x58 (/lib/modules/4.17.0-rc4+/build/vmlinux)
              7fffb70d8234 __GI___libc_write+0x24 (/usr/lib64/libc-2.26.so)
              7fffb7052c74 _IO_file_write@@GLIBC_2.17+0x44 (/usr/lib64/libc-2.26.so)
                  5afc1818 [unknown] ([unknown])
              7fffb7051a60 new_do_write+0x90 (/usr/lib64/libc-2.26.so)
              7fffb7054638 _IO_do_write@@GLIBC_2.17+0x38 (/usr/lib64/libc-2.26.so)
              7fffb7054bbc _IO_file_overflow@@GLIBC_2.17+0x14c (/usr/lib64/libc-2.26.so)
              7fffb7055a24 __overflow+0x64 (/usr/lib64/libc-2.26.so)
              7fffb7044548 _IO_puts+0x218 (/usr/lib64/libc-2.26.so)
                  10000440 main+0x20 (/home/sandipan/test)
              7fffb6fe36a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fffb6fe3898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])
  ...
Signed-off-by: default avatarSandipan Das <sandipan@linux.vnet.ibm.com>
Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Link: http://lkml.kernel.org/r/20180517063326.6319-2-sandipan@linux.vnet.ibm.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      7903a708
  11. 17 May, 2018 9 commits
  13. 16 May, 2018 6 commits
  15. 15 May, 2018 10 commits
    • Adrian Hunter's avatar
      perf tools: Use the "_stest" symbol to identify the kernel map when loading kcore · 56549978
      Adrian Hunter authored 
      The first symbol is not necessarily in the kernel text.  Instead of
using the first symbol, use the _stest symbol to identify the kernel map
when loading kcore.

This allows for the introduction of symbols to identify the x86_64 PTI
entry trampolines.
Signed-off-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1525866228-30321-6-git-send-email-adrian.hunter@intel.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      56549978
    • Arnaldo Carvalho de Melo's avatar
      perf bpf: Add probe() helper to reduce kprobes boilerplate · d8fc764d
      Arnaldo Carvalho de Melo authored 
      So that kprobe definitions become:

  int probe(function, variables)(void *ctx, int err, var1, var2, ...)

The existing 5sec.c, got converted and goes from:

  SEC("func=hrtimer_nanosleep rqtp->tv_sec")
  int func(void *ctx, int err, long sec)
  {
  }

To:

  int probe(hrtimer_nanosleep, rqtp->tv_sec)(void *ctx, int err, long sec)
  {
  }

If we decide to add tv_nsec as well, then it becomes:

  $ cat tools/perf/examples/bpf/5sec.c
  #include <bpf.h>

  int probe(hrtimer_nanosleep, rqtp->tv_sec rqtp->tv_nsec)(void *ctx, int err, long sec, long nsec)
  {
	  return sec == 5;
  }

  license(GPL);
  $

And if we run it, system wide as before and run some 'sleep' with values
for the tv_nsec field, we get:

  # perf trace --no-syscalls -e tools/perf/examples/bpf/5sec.c
     0.000 perf_bpf_probe:hrtimer_nanosleep:(ffffffff9811b5f0) tv_sec=5 tv_nsec=100000000
  9641.650 perf_bpf_probe:hrtimer_nanosleep:(ffffffff9811b5f0) tv_sec=5 tv_nsec=123450001
  ^C#

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-1v9r8f6ds5av0w9pcwpeknyl@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      d8fc764d
    • Arnaldo Carvalho de Melo's avatar
      perf bpf: Add license(NAME) helper · 1f477305
      Arnaldo Carvalho de Melo authored 
      To further reduce boilerplate.

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-vst6hj335s0ebxzqltes3nsc@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      1f477305
    • Arnaldo Carvalho de Melo's avatar
      perf bpf: Add kprobe example to catch 5s naps · 7542b767
      Arnaldo Carvalho de Melo authored 
      Description:

. Disable strace like syscall tracing (--no-syscalls), or try tracing
  just some (-e *sleep).

. Attach a filter function to a kernel function, returning when it should
  be considered, i.e. appear on the output:

  $ cat tools/perf/examples/bpf/5sec.c
  #include <bpf.h>

  SEC("func=hrtimer_nanosleep rqtp->tv_sec")
  int func(void *ctx, int err, long sec)
  {
	  return sec == 5;
  }

  char _license[] SEC("license") = "GPL";
  int _version SEC("version") = LINUX_VERSION_CODE;
  $

. Run it system wide, so that any sleep of >= 5 seconds and < than 6
  seconds gets caught.

. Ask for callgraphs using DWARF info, so that userspace can be unwound

. While this is running, run something like "sleep 5s".

  # perf trace --no-syscalls -e tools/perf/examples/bpf/5sec.c/call-graph=dwarf/
     0.000 perf_bpf_probe:func:(ffffffff9811b5f0) tv_sec=5
                                       hrtimer_nanosleep ([kernel.kallsyms])
                                       __x64_sys_nanosleep ([kernel.kallsyms])
                                       do_syscall_64 ([kernel.kallsyms])
                                       entry_SYSCALL_64 ([kernel.kallsyms])
                                       __GI___nanosleep (/usr/lib64/libc-2.26.so)
                                       rpl_nanosleep (/usr/bin/sleep)
                                       xnanosleep (/usr/bin/sleep)
                                       main (/usr/bin/sleep)
                                       __libc_start_main (/usr/lib64/libc-2.26.so)
                                       _start (/usr/bin/sleep)
  ^C#

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-2nmxth2l2h09f9gy85lyexcq@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      7542b767
    • Arnaldo Carvalho de Melo's avatar
      perf bpf: Add bpf.h to be used in eBPF proggies · dd8e4ead
      Arnaldo Carvalho de Melo authored 
      So, the first helper is the one shortening a variable/function section
attribute, from, for instance:

  char _license[] __attribute__((section("license"), used)) = "GPL";

to:

  char _license[] SEC("license") = "GPL";

Convert empty.c to that and it becomes:

  # cat ~acme/lib/examples/perf/bpf/empty.c
  #include <bpf.h>

  char _license[] SEC("license") = "GPL";
  int _version SEC("version") = LINUX_VERSION_CODE;
  #

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-zmeg52dlvy51rdlhyumfl5yf@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      dd8e4ead
    • Arnaldo Carvalho de Melo's avatar
      perf bpf: Add 'examples' directories · 8f12a2ff
      Arnaldo Carvalho de Melo authored 
      The first one is the bare minimum that bpf infrastructure accepts before
it expects actual events to be set up:

  $ cat tools/perf/examples/bpf/empty.c
  char _license[] __attribute__((section("license"), used)) = "GPL";
  int _version __attribute__((section("version"), used)) = LINUX_VERSION_CODE;
  $

If you remove that "version" line, then it will be refused with:

  # perf trace -e tools/perf/examples/bpf/empty.c
  event syntax error: 'tools/perf/examples/bpf/empty.c'
                       \___ Failed to load tools/perf/examples/bpf/empty.c from source: 'version' section incorrect or lost

  (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
  #

The next ones will, step by step, show simple filters, then the needs
for headers will be made clear, it will be put in place and tested with
new examples, rinse, repeat.

Back to using this first one to test the perf+bpf infrastructure:

If we run it will fail, as no functions are present connecting with,
say, a tracepoint or a function using the kprobes or uprobes
infrastructure:

  # perf trace -e tools/perf/examples/bpf/empty.c
  WARNING: event parser found nothing
  invalid or unsupported event: 'tools/perf/examples/bpf/empty.c'
  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
  #

But, if we set things up to dump the generated object file to a file,
and do this after having run 'make install', still on the developer's
$HOME directory:

  # cat ~/.perfconfig
  [llvm]

	dump-obj = true
  #
  # perf trace -e ~acme/lib/examples/perf/bpf/empty.c
  LLVM: dumping /home/acme/lib/examples/perf/bpf/empty.o
  WARNING: event parser found nothing
  invalid or unsupported event: '/home/acme/lib/examples/perf/bpf/empty.c'
  <SNIP>
  #

We can look at the dumped object file:

  # ls -la ~acme/lib/examples/perf/bpf/empty.o
  -rw-r--r--. 1 root root 576 May  4 12:10 /home/acme/lib/examples/perf/bpf/empty.o
  # file ~acme/lib/examples/perf/bpf/empty.o
  /home/acme/lib/examples/perf/bpf/empty.o: ELF 64-bit LSB relocatable, *unknown arch 0xf7* version 1 (SYSV), not stripped
  # readelf -sw ~acme/lib/examples/perf/bpf/empty.o

  Symbol table '.symtab' contains 3 entries:
     Num:    Value          Size Type    Bind   Vis      Ndx Name
       0: 0000000000000000     0 NOTYPE  LOCAL  DEFAULT  UND
       1: 0000000000000000     0 NOTYPE  GLOBAL DEFAULT    3 _license
       2: 0000000000000000     0 NOTYPE  GLOBAL DEFAULT    4 _version
  #
  # tools/bpf/bpftool/bpftool --pretty ~acme/lib/examples/perf/bpf/empty.o
  null
  #

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-y7dkhakejz3013o0w21n98xd@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      8f12a2ff
    • Arnaldo Carvalho de Melo's avatar
      perf llvm-utils: Add bpf include path to clang command line · 1b16fffa
      Arnaldo Carvalho de Melo authored 
      We'll start putting headers for helpers to be used in eBPF proggies in
there:

  # perf trace -v --no-syscalls -e empty.c |& grep "llvm compiling command : "
  llvm compiling command : /usr/lib64/ccache/clang -D__KERNEL__ -D__NR_CPUS__=4 -DLINUX_VERSION_CODE=0x41100   -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/7/include -I/home/acme/git/linux/arch/x86/include -I./arch/x86/include/generated  -I/home/acme/git/linux/include -I./include -I/home/acme/git/linux/arch/x86/include/uapi -I./arch/x86/include/generated/uapi -I/home/acme/git/linux/include/uapi -I./include/generated/uapi -include /home/acme/git/linux/include/linux/kconfig.h  -I/home/acme/lib/include/perf/bpf -Wno-unused-value -Wno-pointer-sign -working-directory /lib/modules/4.17.0-rc3-00034-gf4ef6a43/build -c /home/acme/bpf/empty.c -target bpf -O2 -o -
  #

Notice the "-I/home/acme/lib/include/perf/bpf"

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-6xq94xro8xlb5s9urznh3f9k@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      1b16fffa
    • Ravi Bangoria's avatar
      perf buildid-cache: Warn --purge-all failures · d8ed87bc
      Ravi Bangoria authored 
      Warn perf buildid-cache --purge-all failures in non verbose mode.

Ex.:

  $ sudo chown root:root /home/ravi/.debug -R
  $ sudo chmod 700 /home/ravi/.debug/ -R
  $ ./perf buildid-cache -P
    Couldn't remove some caches. Error: Permission denied.
Suggested-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: default avatarRavi Bangoria <ravi.bangoria@linux.ibm.com>
Acked-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20180510043651.12189-1-ravi.bangoria@linux.ibm.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      d8ed87bc
    • Arnaldo Carvalho de Melo's avatar
      perf tests parse-events: Add intel_pt parse test · b3f58c8d
      Arnaldo Carvalho de Melo authored 
      To avoid regressions such as the one fixed by 4a35a902 ("Revert
"perf pmu: Fix pmu events parsing rule""), where '-e intel_pt//u' got
broken, with this new entry in this 'perf tests' subtest, we would have
caught it before pushing upstream.
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-kw62fys9bwdgsp722so2ln1l@git.kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      b3f58c8d
    • Arnaldo Carvalho de Melo's avatar
      Merge remote-tracking branch 'tip/perf/urgent' into perf/core · 291c161f
      Arnaldo Carvalho de Melo authored 
      To pick up fixes, notably the revert for the intel_pt//u regression.
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      291c161f
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